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IMPERIAL INTERNATIONAL JOURNAL OF ECO-FRIENDLY

TECHNOLOGIES (IIJET)

Vol. 1 January-June 2016 Issue 2

Chief Editor :

Shri S.K Jagwani

Director

Biofuels and Battery

Operated Vehicles (BoV)

MNRE Editors :

Dr. Ashwini Sharma

Associate Professor

North Cap University

Dr. Ashutosh Dwivedi

Director

BNCET

Co-Editor:

Miss. Harminder Kaur

CONTENTS

PV Power System Based MPPT Z-Source Inverter to Supply a

Sensorless BLDC Motor 59-62 R.Sibiraj*, N.K.Ramesh Krishnan**

Graphene Solar Cell 63-68 Ananthkrishnan H.*, Raut Chetan Krishna**

Solar car 69-71 Team Shakthi Member

Design And Optimization Of Passenger ATV Knuckle 72-76 Vishnu Vardhan Y*, D. Vijay Reddy**, K. Siva Sankar Reddy***, E. Bhargav

Sai****

Solar Panel Parameters Monitoring Using Arduino 77-82 Shaheen Rasheed*, Karthik Ss*

Solar Powered Vechile 83-91 Team- Arka Shakata

PUBLISHED BY:

IMPERIAL INTERNATIONAL JOURNAL

Web: www.imperialsociety.in

Imperial International Journal of Eco-friendly TechnologiesVol. - 1, Issue-2 (2017), pp.59-62

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PV Power System Based MPPT Z-SourceInverter to Supply a Sensorless BLDC Motor

R.Sibiraj*, N.K.Ramesh Krishnan**

*, **Department of Electrical and Electronics Engineering

Abstract

This paper proposes a new PV power system feeding aSensorless brushless dc motor (BLDC) driving a waterpump. A Zsource inverter (ZSI) is controlled to extractthe maximum power from PV array and supplies theBLDC motor instantaneously. The BLDC motor isdriven with variable reference speed dictated frominstant maximum PV power by a hysteresis currentcontrol loop. Despite the conventional PV waterpumping systems, employing a two stages converter, theproposed system enjoys one stage power conversion.Therefore, less number of power switches, less switchinglosses and lower cost are obtained. By proper designingof control system parameters and maximum powerpoint tracking (MPPT) method for PV array, goodsteady state and transient performances have beenachieved in response to different operation conditionsfor PV array. Sensorless drive with low torque ripple isprovided for the BLDC motor. The system wassimulated by PSCAD/EMTDC software for a PV arrayof 1 kW.

I. INTRODUCTION

As the sources of conventional energy are dwindling fastwith a corresponding rise in cost, considerable attention isbeing paid to other alternative energy sources. Solar energywhich is free and abundant in most parts of the world hasproven to be a challenging source of energy in manydeveloping and developed countries. The solar energy asPV power systems can be operated as a stand-alone, hybridor grid connected systems. The first schemes found a wideapplication in remote regions to meet small, but essentialelectric power requirement such as water pumping systems.Photovoltaic (PV) water pumping systems have beenincreasingly popular in remote areas where grid is notaccessible or is too costly to install. These systemsaremostly used for agriculture and household purposes. Anumber of dc motor driven PV pumps are already in use inseveral parts of the world. But they suffer frommaintenance problems due to the presence of thecommutator and brushes. Also some pumping system basedon induction motor (IM) have proposed where reliabilityand maintenance-free operations are important. Since mostlow power motors such as single phase

induction motors (IMs) used for residential applicationsthat drive low torque loads need to have a complex controldrive system. So it can be more efficient to overcomementioned problems by choosing a suitable motor insteadof a DC or IM one. Having lower power range, simplestructure and controllability, BLDC motors can beconsidered as a suitable alternative. Some early studiesbased on a BLDC motor have been done for PV waterpumping systems . The investigation is based on boostconverter which drives a BLDC motor. Because the BLDCmotor is not sensorless, the control drive system isrelatively complex compare to those use sensorless BLDCmotor. In addition the sensorless BLDC motor providesbetter efficiency and better reliability in the same volumeand size. Besides, these systems have employed two powerstages converters, a DC/DC boost converter in order toaccomplish maximum power point tracking(MPPT) of thePV array and a DC/AC inverter to provide an alternativevoltage or current at the output of inverter. But recentpapers on PV power systems suggest less numbers ofpower stage conversions for enhancing the overall systemefficiency. In this paper a sensorless BLDC motor has beendriven by a three-phase ZSI instead of a two stages powerconverter. The schematic block diagram of the proposedPV water pumping system is shown in Fig. 1. As it is clearfrom the figure the system consist of a PV array, asensorless BLDC motor, a three-phase ZSI and the controlsystem. By generating suitable signals for power switchesof ZSI, the system is controlled for different operationconditions such as variations of sun irradiation andtemperature levels. Fig. 1. Block diagram of the proposedsystem The maximum power of PV array is extracted byMPPT control method and then is fed to the sensorlessBLDC motor.Considering that the PV power varies todifferent environment conditions, the sensorless BLDCmotor should be driven by variable reference speed. Inorder to achieve the reference speed for sensorless BLDCmotor, the input voltage of inverter is regulated at aconstant value (Vinref=300V). The simulation results ofthe whole system are given to clarify the advantageous ofproposed system. The other advantages of the system areless power switches, smaller capacitance and inductancevalues in comparison with boost converter and fastdynamic response.

AI. PV ARRAY MODEL AND MPPT

59The nonlinear Ipv–Vpvand Ppv Vpvcharacteristics of solarcells are well known. constant coefficient and depends uponthe cell material. These parameters for the silicon solar panel

manufactured by the Iranian Optical Fiber Fabrication Co.(OFFC) used for the theoretical analyses of this paper arevalued in Table I.

TABLE IOFFC SILICON SOLAR PANEL PARAMETERS 2 .926 S C Short-circuit current I

19.39 OC Open circuit voltage VIn order to achieve more PV power, Ns numbers of PVmodules are serried as a PV string and then Npnumbers ofPV strings are paralleled as a PV array. As the voltage andcurrent of a PV array vary in respect to insolation andtemperature levels, the equation (1) has been computed forseveral insolation levels (G=600, 800, 1000 W/m2) for thesame temperature level (T=25oC). The Vpv-Ipvand Ppv-Vpvcharacteristics of the PV array have been shown in Fig.

3. These figures illustrate the nonlinear variations ofthe PV maximum power point respect toirradiation levels. In this paper PV system ismodeled in the PSCAD program as a DC voltagesource based on equation (1).

There is only one operating point on every Ppv-Vpvcharacteristic that the maximum PV power can beextracted. Providing this operating point for PV array iscalled as Maximum Power Point Tracking (MPPT)performance employed by MPPT controller. There areseveral methods to accomplish MPPT for PV array [10]-[12]. Incremental conductance MPPT algorithm In thispaper the control unit tracking the maximum power point inPV array is given by the flowchart of the incrementalconductance algorithm as is shown in . In this figure theVkand Ikare the momentary voltage and current of the PVarray and Vk-l and Ik-1 are the previous voltage andcurrent, respectively. The dP/dVterm can be replaced byI+(ΔI/ΔV)V. The output of the MPPT algorithm is the DC voltage reference (VPVref).

BI. BLDC MOTOR DRIVEPermanent magnet DC motors use mechanical commutator and brushes to achieve the commutation. However, BLDC motors adopt Hall Effect sensors in place of mechanical commutator and brushes. The stators of BLDC motors are the coils, and the rotors are the permanent magnets. The stators develop the magnetic fields to make the rotor rotating. Hall Effect sensors detect the rotor position as the commutating signals. Therefore, the BLDC motors use permanent magnets instead of coils in the armature and so do not need brushes. As the rotor position is detected by incremental encoder then the Hall Effect sensors can be removed. So a motor without Hall Effect sensors is called as a sensorless BLDC motor. In this paper, a three-phase and two polesensorless BLDC motor is used. For the three phases BLDC motor the back EMF and phase current waveforms with 120° conduction mode . the mechanical speed of the rotor. The equation of motion is:

Imperial International Journal of Eco-friendlyTechnologies Vol. - 1, Issue-2 (2017), pp.59-62

IIJET( )/ r e L rd T T B JdtwhereB is the damping constant, J is the moment of inertiaof the drive and TL is the hydrodynamic load torque of thecentrifugal pump which is related with speed as following:2

L r T=K (5)whereK is the constant of the pump torque. The electricalfrequency related to the mechanical speed for a motor withPnumbers of poles is:( /2) e r=P (6)

BASIC OPERATION PRINCIPLES OFZSI

The impedance network which is made of an X shape LCnetwork can boost the dc input voltage (Vo) in respect tothe interval of shoot-through zero state (T0) during aswitching cycle (T). In conventional VSI there are eightpermissibleswitching states: six active and two zero states,while during the zero states there is no difference for theload if the upper three, the lower three or all the sixswitches are gated on (all the states short the outputterminal of the inverter and produce zero voltage to theload). As discussed in [17] in ZSI, during the zero states allthe switches are gated on (shoot-through state) and thisstate is used to achieve boosting dc input voltage.Therefore in ZSI, there are six active states and two zerostates which are the same as conventional inverter and anaddition shoot-through state (it is forbidden in conventionalinverters) which is utilized advantageously to boost the dc-bus voltage. VC1 and VC2 are capacitors voltages ofimpedance network which are the same due to circuitsymmetry. B is the boost factor of ZSI. Vdand VO denotethe input and output voltages of impedance networkrespectively.

V. CONTROL SYSTEM DESCRIPTION

The drive system consists of the PI speed controller,reference current generator, hysteresis current controller,three-phase ZSI and the motor-load unit. First the referencevoltage of PV array is determined by the IC MPPTcontroller and compared with the PV array voltage. Thenthe error signal is processed by a PI controller to obtain theshoot through interval time of ZSI (T0). The shoot throughstate can be performed through the ZSI regulating the inputdc voltage of inverter (Vin). The voltage error (e=Vref-Vin)is considered by a PI controller to utilize as reference speedfor BLDC motor. Then the speed of the motor is comparedwith its reference value, and the speed error is processed inthe PI speed controller. The output of this controller isconsidered as the reference torque. A limit is put on thespeed controller output depending on the permissiblemaximum winding currents. The reference currentgenerator block generates the three phase reference

60currents using the limited peak current magnitude decidedby the controller and the position sensor. The motorcurrents are compared with the reference currents and the

hysteresis current controller regulates the winding currents(ia, ib, ic) within the small band around the referencecurrents. These switching commands and the Z-Sourceswitching commands are ORed to drive inverter switches.

VI. SIMULATION RESULTSThe proposed system was simulated by PSCAD/EMTDC to evaluate the system capability in response to different operation conditions The PV array output power range is about 0.5kW to 1kW. The other simulation parameters related to BLDC motor, load torque constant (K), ZSI and LC filter are presented. Three different operating conditions are indicated by Fig. 8 showing the simulated results for motor phase currents, rotor speed ,electromagnetic and load torques and PV output power for the following stages respectively.. A. First stage (0<t<1.5sec) In this stage the system starts to operate, while BLDC motor is at the stationery state. Also the irradiation level of sun is about G=600W/m2, and the temperature level is about T=10oC. At first the MPPT controller regulates the shoot-through time (T0) of ZSI, so the PV output power is adjusted to its maximum value (Pmpp=520W) and the capacitors are being charged simultaneously. This situation continues until the input dc voltage of inverter (Vin) boosts to its reference valueat t=0.14sec. At this time the reference speed increases from zero to its nominal value, i.e. 1433r.p.m. and once Vin increases totrack Vref. Considering that the load torque is in proportion to the s Asshown in Fig. 8 (a), the three-phase starting currents for BLDC motor smoothly increase to reach their steady state values, i.e. 3.65A at t=0.8sec. In this state the maximum power of PV array is drawn to supply the motor. The steady state values are;

N=1433rpm, TL=2.6N.m and Te=2.9N.m. Once back emf should be provided the current of the motor should be reversed.Because of winding inductance the currents force theswitches to communicate. So current ripple is unavoidableand it results in the electromagnetic torque ripple. B.Second stage (1.5<t<3sec) To illustrate the MPPTperformance of ZSI, an increasing in the light intensity ofsun from G=600W/m2 to G=900W/m2 at t=1.5sec ishappened. As the MPPT controller tracks the PV The drivesystem provides the second steady state situation for motorat t=2sec. In this situation N=1760rpm, TL=3.8N.m,Te=4.2N.m. C. Third stage (3<t<4.5sec) As the influence oftemperature level on PV power cannot be completelyignored so this stage offers a step change in temperaturelevel from T=10oC to T=25oC at t=3sec as shown in Fig.

8. As it is clear from the Fig. 8(d) the maximumpower of PV array is decreased to Pmpp=750Wand rapidly tracked byMPPT controller att=3.2Sec. A smaller amount of PV


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power leads to another steady state situation for BLDCmotor. The new steady state situation is verified byN=1590rpm, TL=3.25N.m, Te=3.5N.m and currentamplitude of 4.2A.

VII. CONCLUSION

This paper proposes a sensorless BLDC motor supplied byPV array based on ZSI. In spite of conventional PV systemneeding two stages of power converters the proposedsystem has employed just a three phase ZSI extracting themaximum power of PV array and driving a sensorlessBLDC moto simultaneously for different operationconditions. Less number of power switches associated withless switching losses is achieved. Also the good steadinesscapability of system for every simulated stage can beclearly seen from the simulation results. Less power losses,rapid tracking of MPPT and low electromagnetic torqueripple, demonstrating high current control capability, havebeen achieved by appropriate designing an integratedcontroller for whole system.

REFERENCES

[1] M. G. Jabori, “A contribution to the simulation and designoptimization of photovoltaic systems,” IEEE Trans. on EC, vol. 6,no.3, 1991, pp. 401-406.

[2] J. Samin and et al, “optimal sizing of Photovoltaic Systems inVaried Climates,” Elsevier , Solar Energy, vol. 6, No. 2, 1997,pp.97-107.

[3] Z. Zinge, “Optimum Operation of a Combined System of aSolar Cell Array and a DC Motor,” IEEE Trans. on PAS, vol. pas-100, no. 3, 1981,pp. 1193-1197.[4] C. Mummadi, “Steady State and Dynamic PerformancesAnalysis of PV Supplied DC Motors Fed from IntermediatePower Converter,” Elsevier Solar Energy Materials & Solar Cells, vol-61, 2000, pp. 365-381.

[5] A. Saadi And A. Moussi, “ Optimisation of Chopping ratio ofBack-Boost converter by MPPT technique with a variable reference voltage applied tothe Photovoltaic water Pumping System,” IEEE ISIE.Conf 2006, vol-7, 2000, pp. 1716-1720.

[6] Arrouf M, Bouguechal N, “Vector control of an induction motorfed by a photovoltaic generator,’’ Elsevier Applied Energy 2003;vol.74, issues 1-2,January-February 2003, pp.159-167.

[7] M.A. Daud, M. Mahmoud, "Solar powered induction motor-driven water pumps operating on a desert well, simulation andfield tests," RenewableEnergy, vol. 30, issue 5, April 2005, pp.701-714.

[8] R. Akkaya , A.A. Kulaksız, O¨ . Aydog˘du, “DSP implementationof a PV system with GA-MLP-NN based MPPT controllersupplying BLDC motor drive,” Elsevier Energy Conversion andanagement, vol 48, issue 1, January 2007, pp. 210-218

[9] M. Masoum “Design, Construction and Testing of a Voltage-based Maximum Power Point Tracker (VMPPT) for Small

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IIJETSatellite Power Supply,” 13th Annual AIAA/USU Conference onSmall Satellite.

[10] E. Koutroulis, K. Klaitzakis and N.C. Voulgaris,“Development of Microcontroller-Based Photovoltaic MaximumPower Point Tracking Control System,” IEEE Trans. PowerElectronics, vol.16, no. 1, January 2001, pp. 46-54.[11] N. Khaehintung, B. Tuvirat, K. Pramotung and P. Sirisuk, “ALow-Cost Solar-Powered Light-Flasherwith Built-in MaximumPower Point Tracking,” Proc. of Int. PVSEC-14, pp. 867-868,Bangkok, Thailand, 2004.[12] N. Femia, “Optimizing Duty-cycle Perturbation of P&OMPPT Technique,” PESC 2004, IEEE 35th Annual, vol 3, 20-25 June 2004, pp. 1939 –1944.

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Graphene Solar CellAnanthkrishnan H.*, Raut Chetan Krishna**

Mechanical Engineering Department, Karmayogi Engineering College, Shelve, Pandharpur.

Abstract

Scientists, environmentalists, companies, countries evenpeople all around the world are looking forwardtowards the development of affordable, inexhaustibleand clean source of energy technologies which will havehuge longer-term benefits. It will increase countriesenergy security through reliance on an indigenous,inexhaustible and mostly import-independent resource,enhance sustainability, reduce pollution, lower the costsof mitigating global warming, and keep fossil fuel priceslower. Sun, solar power/energy being considered thebest among all the alternatives available are mostlydepend on the development of the photovoltaic/solarcells to achieve maximum efficiency/energy from sun.With many new inventions/developments achieved likePerovskite, Quantum dots & organic solar cells;upconversion and downconversion techniques; lightabsorbing dyes; adaptive cells; graphene solar cells etc.Which one to use, which one is, better, has becomeanother important perspective. This paper gives a shortreview on graphene solar cells. Graphene the wondermaterial with its astonishing properties has become thecenter of attraction since the day it was invented andshown to the world by the Professors A.K. Geim and K.Novoselov in 2004 which earned both of them a NobelPrize in Physics. This paper also presents the use ofgraphene in solar cells as a transparent electrode,Schottky junction; counter electrode and even growingthe nanowires on the transparent graphene electrodes.This paper thus strongly support the use of graphene insolar cells and looking forward towards cheap, highlyefficient graphene solar cells.

Keywords: Solar cell, Graphene, Electrode, Powerconversion efficiency, Nanowires.

I. Introduction

Solar energy is radiant light and heat from the sunharnessed using a range of ever-evolving technologies suchas solar heating, photovoltaics, solar thermal energy, andsolar architecture and artificial photosynthesis. Thephotovoltaic effect refers to photons of light excitingelectrons into a higher state of energy, allowing them to actas charge carriers for an electric current. The process isboth physical and chemical in nature, as the first stepinvolves the photoelectric effect from which a secondelectrochemical process takes place involving crystallized

atoms being ionized in a series, generating an electriccurrent. Cells require protection from the environment andare usually packaged tightly behind a glass sheet. Whenmore power is required than a single cell can deliver, cellsare electrically connected together to form photovoltaicmodules, or solar panels.

A. Current ongoing researches

Perovskite solar cells are solar cells that include aperovskite structured (similar to the structure of calciumtitanium oxide, CaTiO3) material as the active layer. Mostcommonly, this is a solution-processed hybrid organic-inorganic tin or lead halide based material. In 2014researchers at California NanoSystems Institute discoveredliquid inks using kesterite (an inorganic substance madefrom Copper, tin, zinc & sulfur and perovskite. Theresearch team was able to create a liquid ink that could besprayed or painted on a surface to make that surface a solarcell thus improving electric power conversion efficiencyfor solar cells.

Another method is the upconversion and downconversionof photon. Photon upconversion is the process of using twolow-energy (e.g., infrared) photons to produce one higherenergy photon; downconversion is the process of using onehigh energy photon (e.g. ultraviolet) to produce two lowerenergy photons. Either of these techniques could be used toproduce higher efficiency solar cells by allowing solarphotons to be more efficiently used. Light-absorbing dyes,typically a ruthenium metal organic dye used as amonolayer of light-absorbing material in the dye sensitizedsolar cell (DSSC).

Quantum dot solar cells (QDSCs) are based on theDSSC architecture but employ low band gapsemiconductor nanoparticles, fabricated with crystallitesizes small enough to form quantum dots such as CdS,CdSe, PbS, etc. instead of organic or organometallic dyesas light absorbers. Organic solar cells and polymer solarcells another new breakthrough are built from thin films(typically 100 nm) of organic semiconductors includingpolymers, such as polyphenylene vinylene and smallmolecule compounds like copper phthalocyanine (a blue orgreen organic pigment) and carbon fullerenes and fullerenederivatives. They can be processed from liquid solution,offering the possibility of a simple roll to roll printingprocess, potentially leading to inexpensive, large scaleproduction.

63Adaptive cells, a kind of cells that change theirabsorption/reflection characteristics depending to respond toenvironmental conditions. Several new versatile

https://en.wikipedia.org/wiki/Sustainability

https://en.wikipedia.org/wiki/Fullerene

https://en.wikipedia.org/wiki/Polyphenylene_vinylene

https://en.wikipedia.org/wiki/Organic_semiconductor

https://en.wikipedia.org/wiki/Polymer_solar_cell

https://en.wikipedia.org/wiki/Polymer_solar_cell

https://en.wikipedia.org/wiki/Organic_solar_cell

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https://en.wikipedia.org/wiki/Cadmium_sulfide

https://en.wikipedia.org/wiki/Quantum_dots

https://en.wikipedia.org/wiki/Nanoparticle

https://en.wikipedia.org/wiki/Band_gap

https://en.wikipedia.org/wiki/Band_gap

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https://en.wikipedia.org/wiki/Quantum_dot_solar_cell

https://en.wikipedia.org/wiki/Monolayer

https://en.wikipedia.org/wiki/Dye

https://en.wikipedia.org/wiki/Ruthenium

https://en.wikipedia.org/wiki/Photon_upconversion

https://en.wikipedia.org/wiki/Electric_power_conversion

https://en.wikipedia.org/wiki/Perovskite

https://en.wikipedia.org/wiki/Kesterite

https://en.wikipedia.org/wiki/California_NanoSystems_Institute

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https://en.wikipedia.org/wiki/Artificial_photosynthesis

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nanostructured electrode materials have been reported forthe development of solar cell applications, such as carbonelectrodes (Single-walled and multi-walled carbonnanotube, graphene oxide (GO) and fullerene), metaloxides (TiO2, SnO2, boron doped ZnO and Cu2O) andconducting polymers. These types of electrode materialslike graphene greatly enhanced the power conversionefficiency of the solar cells.

AI. Graphene

The Nobel Prize in Physics in the year 2010 was awardedto Professors A.K. Geim and K. Novoselov for theirresearch work on graphenes. “Graphene is defined as oneatom thin sheet of carbon atom arranged in a Hexagonalformat or a flat monolayer of a carbon atom that are tightlypacked into Two-dimensional (2D) honeycomb lattice”. Itis the center of an ever growing research effort due to itsunique properties, interesting for both fundamental scienceand applications. This new material has a number of uniqueproperties, which makes it interesting for both fundamentalstudies and future applications. The electronic properties ofthis 2D material lead to, for instance, an unusual quantumHall effect. It is a transparent conductor for which is oneatom thin. It also gives rise to analogies with particlephysics, including an exotic type of tunneling. In additiongraphene has a number of remarkable mechanical andelectrical properties. It is substantially stronger than steel,and it is very stretchable. The thermal and electricalconductivity is very high and it can be used as a flexibleconductor. The electronic structure of graphene is ratherdifferent from usual three-dimensional materials. Grapheneis practically transparent. In the optical region it absorbsonly 2.3% of the light. In contrast to low temperature 2Dsystems based on semiconductors, graphene maintains its2D properties at room temperature.

Graphene had already been studied theoretically in 1947 byP.R. Wallace for calculations in solid state physics. Hepredicted the electronic structure and noted the lineardispersion relation. The wave equation for excitations waswritten down by J.W. McClure already in 1956, and the


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similarity to the Dirac equation was discussed by G.W.Semenoff in 1984. It came as a surprise to the physicscommunity when Andre Geim, Konstantin Novoselov andtheir collaborators from the University of Manchester(UK), and the Institute for Microelectronics. Technology inChernogolovka (Russia), presented their results ongraphene structures. They published their results inOctober of 2004 in Science. De Heer’s group publishedtheir first paper on transport measurements on thin carbonfilms. The two papers were published back-to-back in thesame issue of Nature in November of 2005.

Currently there are innumerable techniques available forthe preparation of graphene. However, one can broadlyclassify them into two main categories, i.e. bottom-up (e.g.,CVD or chemical vapour deposition, epitaxial growth onSiC, arc discharge, chemical synthesis etc.) and top-down(e.g., exfoliation methods) processes. Of which CVD andexfoliation methods are widely used.

BI. Graphene solar cells

Graphene can be used in solar cells in many ways; some ofthem are briefly described below.

A.Graphene as a transparent electrode

Graphene has been proposed to be an effective transparentelectrode to replace Indium Tin Oxide (ITO) in solar cell asgraphene exhibits excellent properties such as low-sheetresistance, high transmittance, good mechanical property,and good thermal and chemical stability. As early as 2007scientists fabricated polymer solar cells using reducedgraphene oxide as transparent electrode and achieved aPCE (Power Conversion Efficiency) of 0.26%. Afterwards,chemical vapor deposition (CVD) approach has been usedby many groups to synthesize single or few layer graphenefilms with large area for energy harvesting applicationswhich is a significant advance in this field. The efficiencyof organic solar cells with graphene electrode was 1.18%,which is close to that of organic solar cells with ITOelectrode (~1.27%). In 2011 researchers used layer by layertransfer method to fabricate multilayer CVD graphenefilms with less defects and lower sheet resistance. Theorganic solar cells with the electrode of four layersgraphene have an improved PCE up to 2.5%, which is83.3% of the PCE of ITO based devices. For the hybridsolar cell, it is demonstrated the use of graphene astransparent conductive electrodes with the structure ofgraphene/organic/silicon, which has a PCE of 10%.However, the solar cell has a very small device area ofabout 0.1 cm2.

B. Graphene as a Schottky junction diode Development of graphene-based Schottky junction solar cells, including graphene on silicon Schottky junction solar cells and graphene/single Schottky junction solar cells

64kinds of solar cells are promising in developing diverse novelhigh-efficiency and low-cost nanoscale power sources, whichare desired in future integrated nanosystems Although

various impressive progresses have been made, challengesstill remain in this field. Persistent effort of furtherimproving the PCE of the graphene-based Schottkyjunction solar cells, by developing new concepts, newtechnologies, and new device structures, is stillindispensable. Among them, graphene/silicon (Si) solar cellis most popular and much attention has been dedicated to it.The state of art Eta (conversion efficiency) of graphene/Sisolar cell is limited to 8.6% and 14.5%, without and withanti-reflection coating, respectively. A recent work showedthat the initial efficiency of graphene/Si (G/Si) solar cellreached 1.9%, and it could be further improved to 8.6% byTFSA (trifluoro methane sulfonyl amide) doping. Due tothe simple design and efficient photovoltaic conversion,G/Si Schottky junction solar cells have attracted increasinginterests and exciting progress has been achieved recently.

Compared with Si, GaAs is commonly used to fabricatehigh efficient solar cells. Suitable direct band gap energy of1.42eV and high electron mobility (8000cm2/V·s at 300K),which is about six times of that of Si (1350 cm2/V·s at300K), make GaAs one of the best candidates for highperformance solar cells. It has been reportedgraphene/GaAs solar cells which can only convert 1.95%of input light into electricity, which is poor considering theadvantages of GaAs over Si. High performance solar cellswith Eta of 10.4% for doped graphene/GaAs structure areachieved. Through anti-reflection technique, Eta has beenfurther improved up to 15.5%, which is higher than thestate of art Eta for graphene/Si system. It is noteworthy that25.8% of Eta can be reasonably calculated for the van derWaals Schottky diode formed between graphene and GaAs,promising the practical application of graphene/GaAsheterostructure in solar cells.

1. Structure of the graphene/GaAs solar cells

The schematic structure of graphene/GaAs solar cell isillustrated in Fig. which is composed of GaAs substrate,graphene and electrodes. A SiNx film is sandwichedbetween graphene and GaAs as the dielectric insulatinglayer.


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By taking advantage of graphenes favorable electrical andoptical properties, and then adding an organic dopant,researchers have achieved the highest power conversionefficiency yet for a graphene-based solar cell. The 1.9% powerconversion efficiency of the undoped devices increases bymore than four times to 8.6% after doping. The researchers,led by Sefaattin Tongay and Arthur F. Hebard at the Universityof Florida in Gainesville, have published their study on thehigh efficiency graphene solar cells in a recent issue of NanoLetters. "Here, not only we have taken advantage of graphenesbeautiful optical transparency, but also we have reducedgraphenes electrical resistance by adjusting the Fermi level ofgraphene using a cheap and environmentally stable organiccoating layer," Tongay told Phys.org. "During this step, Naturefavored us by yielding a higher rectification and electric fieldat the interface, further improving the solar cell's efficiency."

In the new solar cells, a single layer of graphene placed ontop of a silicon wafer serves as a Schottky junction, themain component of simple photovoltaic devices calledSchottky junction solar cells. Under illumination, electron-hole pairs are photogenerated in the silicon. Thephotogenerated electrons and holes are separated by theSchottky junction's built-in electric potential and collectedby the oppositely charged graphene and semiconductorcontacts. This one-way flow of current is a definingproperty of the Schottky junction and enables thegeneration of power from the device. While graphene-based Schottky junction solar cells have been demonstratedin the past, here the researchers took an extra step anddoped the graphene with the organic chemical TFSA usinga simple spin-casting method.

Doping allowed the researchers to adjust graphenes Fermilevel (a measure of electron potential energy), whichresulted in two changes that improved the solar cells'overall efficiency: a reduction in the graphenes resistanceand an increase in the solar cell's built-in potential, whichleads to a more efficient separation of the electron holepairs generated by the absorbed photons. With their 8.6%efficiency, the doped devices provide a significantefficiency improvement over other graphene-basedSchottky junction solar cells, which have so fardemonstrated power conversion efficiencies ranging from0.1% to 2.86%. Compared with Schottky junction solarcells that use indium tin oxide, those that use graphenehave several advantages. For instance, the ability to tunegraphenes properties enables researchers to optimize solarcell efficiency and use the graphene layer on othersemiconductors besides silicon.

C. Graphene as counter electrode

Dye sensitized solar cells (DSSCs) are attracting attentionglobally because of their low cost, high energy conversion

65efficiency and potential applications. Graphene has beenextensively utilized in organic photovoltaic (PV) cells owingto its excellent optical and electrical characteristics, whichare exploited in transparent conductive films or electrodes.

Some researchers have reported on composite grapheneTiO2 photoelectrodes in DSSCs. DSSCs with the optimalcomposite TiO2 film can achieve a photoelectricalconversion efficiency of 7.02%. Graphene is alsocommonly used in graphene based counter electrodes inDSSCs. The conventional counter electrode is platinum (Pt)because of its outstanding conductivity, catalytic activity,and stability when in contact with an iodine basedelectrolyte. The expensive Pt can be replaced withgraphene films in DSSCs without significantly sacrificingphotoelectrical efficiency. This replacement can simplyreduce the cost of the fabrication process. Pt free counterelectrode was developed recently by using graphenesupported nickel nanoparticles as catalyst, and thecorresponding solar cell efficiency had an increase of 10%than that of Pt-based DSSCs.

Researchers grew DSSCs with graphene based counterelectrodes, which exhibited a photoelectrical conversionefficiency of as high as 6.81%. Double-layerphotoelectrodes have been used to increase thephotoelectrical conversion efficiency of DSSCs. Manyinvestigations have focused on modifying thenanostructures of TiO2 photoelectrodes to nanospheres,nanospindles, nanorods, nanowires, and others. Manyspecial nanostructures of photoelectrodes can increase thescattering of light and improve the performance of DSSCs.This work develops a new TiO2/graphene/TiO2 sandwichstructure for photoelectrodes. A thin layer of graphene wasinserted into the traditional TiO2 photoelectrode layer,making it a double layer.

DSSCs with the traditional structure were also fabricatedand the characteristics of the prepared DSSCs werecompared. The DSSC with the TiO2/graphene/TiO2sandwich structure exhibited excellent performance andhigher photoelectrical conversion efficiency. Thisimprovement is associated with the increase in electrontransport efficiency and the absorption of light in thevisible range.

D. Graphene as a transparent electrode to grownanofibres

In the past decade or so, scientists and engineers havebegun making photovoltaic solar cells out of organic—thatis, carbon-containing—materials rather than inorganicsilicon. However, two problems have slowed developmentof this promising technology. First, organic solar cells can’tyet convert visible light into electricity as efficiently astheir silicon counterparts can. And second, researchershaven’t been able to find a flexible, transparent, low-cost


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material for the electrode that carries current out of thecell. Silvija Gradecˇak, the Thomas Lord AssociateProfessor in Materials Science and Engineering, and ateam of collaborators from four MIT departments havecome up with methods of dealing with both of thoseproblems. The efficiency challenge, the challenge withconversion efficiency, says Gradecˇak, is getting the rightgeometry inside the organic cell. Any solar cell requirestwo materials, a donor material that absorbs incoming solarenergy and gives off energized electrons, and an acceptormaterial that picks up those electrons and carries them tothe electrode, where they exit the device as electricalcurrent.

In the usual organic solar cell, two polymers act as thedonor and acceptor materials, and they need to beintertwined to provide lots of interfaces for the jumpingelectrons. The difficulty is controlling the nanometer scalestructure inside the organic cell to achieve those interfaceswhile providing pathways for the rapid movement ofelectrons to maximize the current coming out of thedevice. To solve that problem, Gradecˇak has been workingto make a hybrid solar cell by replacing one of the organicpolymers with an inorganic material that will move theelectrons more efficiently. But she adds a special twist: Shemakes the inorganic material into nanowires, microscopicfibers that are a few billionths of a meter in diameter andmillions of times longer. Each nanowire is a single crystal,with an extensive surface area and no defects to interferewith the flow of electrons.

And Gradecˇak’s group, the Laboratory for Nanophotonicsand Electronics has an unmatched ability to grownanowires at any length, diameter, and density desired.With this approach, there’s no need to worry aboutinterconnecting regions of polymers. The electron donormaterial can surround a forest of tall, solid nanowires, anoverall structure that’s predictable and stable andmaximizes contact between the two materials. Assemblingthe solar cell involves growing the nanowires up from atransparent electrode, infiltrating that forest with thepolymer or other electron-donor material, and topping it offwith a second electrode. When the solar cell is in use, lightenters through the transparent electrode, and electronsknocked loose from the donor material move into nearbynanowires. The electrons travel rapidly through thenanowires to the transparent electrode, out along anexternal circuit, and back to the second electrode.

To test their design, Gradecˇak and her collaborators grewnanowires on a transparent electrode and then deposited asolution containing the donor material on top. Images witha scanning electron microscope (SEM) showed that thesolution infiltrated deep into the nanowire array, makinggood contact with the nanowire surfaces and leaving fewvoids to reduce performance. And in experiments with

66fully assembled devices, the presence of the nanowirespushed up efficiency by as much as 35%, depending on thedonor material used. Those results confirm the viability of

their hybrid approach. “By combining the organic andinorganic materials, we bridge the advantages of bothworlds,” says Gradecˇak. “We get solar cells that can beprocessed at a large scale using roll to roll methods, butthey can still have reasonable power conversionefficiencies.”

In this solar cell design, tall, thin nanowires grow up froma transparent electrode and are surrounded by a lightabsorbing polymer or other electron donor method. Asecond electrode tops off the system. Light enters throughthe transparent electrode and energizes electron in thepolymer. The electrons move into the nanowires and flowto the transparent electrode and then out of the device intoan external circuit. After powering, say, a light bulb, theelectrons return to the second electrode and rejoin the holesthey left behind. Using nanowires in place of the usualsecond polymer increases the stability and predictability ofthe structure and allows the electrons to move quickly tothe surface of the device.The first question was whether they could grow nanowireson graphene while preserving the special properties of eachcomponent. The usual way to grow nanowires made of zincoxide, their material of choice is to deposit a seed layer ofzinc oxide a few nanometers thick on a piece of silicon,ITO, or other substrate and then immerse the structure in asolution containing zinc and oxygen ions. The zinc oxidenanowires quickly grow straight up from the surface.Because zinc oxide has a crystalline structure, thenanowires grow from individual crystals in the seed layerto form a forest of tall, skinny wires. But when Gradecˇakand her colleagues tried to deposit the necessary seed layeron graphene, the zinc oxide solution separated into dropletsrather than forming an evenly distributed coating. Theproblem is that the structure of graphene is extremelystable, with the carbon atoms in each sheet tightlyconnected with one another in a hexagonal pattern. As aresult, graphene repels water, so the zinc oxide solutionbeads up instead of spreading out. Other researchers havetried to grow nanowires on graphene by first roughening up


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the graphene surface using oxygen plasma, but thatapproach destroys the graphene, and the properties of thenanowires are not well known.

To preserve the integrity of the materials, Gradecˇak andher team tried a different approach: using an interlayerbetween the graphene and the zinc oxide. They identifiedtwo commercially available polymers that would do thetrick. The polymers would wet the graphene, covering theentire surface with a thin coating on which the zinc oxidecould disperse.Better still, the polymers are electrically conductive andchemically compatible with zinc oxide, and they won’tinteract strongly with the graphene, so it should remainboth transparent and conductive. To test this approach, theteam grew zinc oxide nanowires on graphene with thepolymer interlayer and on ITO, the standard transparentelectrode material, under identical conditions.The resultsshow nanowires grown on ITO, viewed from two anglesand grown on graphene with the polymer interlayer. Theimages confirm that the nanowires grown on the twomaterials are comparable in their uniformity, shape, andalignment. “So we can grow nanowires on graphene, andthe quality of the nanowires is equal to or better than thosegrown on ITO,” says Gradecˇak.The final step was to test the performance of completesolar cells, which team members assembled as shown inthe schematic diagram above. First they stacked threemonolayers of graphene on quartz, their sample surface.Then they deposited the polymer interlayer followed by thezinc oxide seed layer, the nanowires, the electron donormaterial, and finally a second electrode of gold on a thinlayer of molybdenum oxide.

IV. Conclusion

Graphene, a next generation material which when used insolar cells helps in improving the overall efficiency as wellas a low cost substitute to various materials like Platinum,Indium etc. Considering the recent developments graphenesolar cells could be developed in order to compete with theconventional solar cells. With emerging technologies

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Acknowledgment

The authors are grateful for the contributions of their advisorProf. S. A. Kale, Head Engineering Research & DevelopmentDepartment at Karmayogi Engineering College. Also they areindebted to Prof. D. V. Bhosale, Prof. R. R. Halcherikar and Prof.M. S. Sawane of Karmayogi Engineering College for theirsupport and valuable advices. It would not have been possible tocomplete this paper without the support and encouragement ofPrincipal of Karmayogi Engineering College, Shelve PandharpurDr. S. P. Patil. Last but not the least the authors are heartilythankful to all the personalities who have directly or indirectlyhelped them.

References

[1] Hongwei ZHU et al.,”Chemical Doping and Enhanced Solar Energy Conversion of Graphene/Silicon Junctions.”

[2] Shisheng Lin et al., “High performance solar cells basedon graphene/GaAs hetero structures.”

[3] Chen et al., “Improving the performance of dye-sensitized solar cells with TiO2/graphene/TiO2sandwich structure”, Nanoscale Research Letters 2014,9:380.

[4] Lisa Zyga, “Dopant gives graphene solar cells highest efficiency yet”, 2012.

[5] AlejandroManzano-Ramírez et al., “A Review on theEfficiency of Graphene-Based BHJ Organic SolarCells”, Journal of Nanomaterials Volume 2015, ArticleID 40659.

[6] MIT energy reviews, autumn 2013.[7] Qiaoliang Bao et al.,“Graphene-based transparent

electrodes for hybrid solar cells”, Frontiers in Materials,Nov

2014[8] Yu Ye et al., “Graphene-based Schottky junction solar

cells”, Journal of Materials Chemistry, Nov2012[9] Onkar I. Nichal et al., “Graphene an overview”,

Proceedings of ICDMM 2014

Authors Biography

1. Ananthkrishnan H.U.G. Student, Karmayogi Engineering College,

Shelve- PandharpurEmail:[email protected] Contact No:-+919930962482

2. Raut Chetan KrishnaU.G. Student, Karmayogi Engineering College, Shelve-PandharpurEmail:[email protected] Contact No:-+91 7507822078


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Solar carTeam Shakthi Member

Abstract

Most of the power generated nowadays is producedusing fossil fuels, which emit tons of carbon dioxide andother pollution every second. More importantly, fossilfuel will eventually run out. In order to make thedevelopment of our civilization sustainable and causeless harm to our environment, people are looking fornew source of substitute clean energy. Because of theincreasing demands in clean energy, the solar energyindustry is one of the fastest growing forces in themarket. Nowadays there are several major directionsfor solar technology development. The renewableenergy is vital for today’s world as in near future thenonrenewable sources that we are using are going to getexhausted. The solar vehicle is a step in saving thesenonrenewable sources of energy. The basic principle ofsolar car is to use energy that is stored in a batteryduring and after charging it from a solar panel. Thecharged batteries are used to drive the motor whichserves here as an engine and moves the vehicle inreverse or forward direction. The electrical tappingrheostat is provided so as to control the motor speed.This avoids excess flow of current when the vehicle issupposed to be stopped suddenly as it is in normal carswith regards to fuel. This idea, in future, may helpprotect our fuels from getting extinguished. All recentelectric vehicles present drive on AC power suppliedmotor. The vehicle designed is controlled byELECTRICAL means and not by ELECTRONICmeans D.C.

Keywods: Motor, Rheostat Control, Lead-acid Batteries,Solar panel, Battery Cycle.

I. INTRODUCTION

The Energy is one of the most vital needs for humansurvival on earth. We are dependent on one form of energyor the other for fulfilling our needs. One such form ofenergy is the energy from FOSSIL FUELS. We use energyfrom these sources for generating electricity, runningautomobiles etc. But the main disadvantages of theseFOSSIL FUELS are that they are not environmentalfriendly and they are exhaustible. To deal with theseproblems of FOSSIL FUELS, we need to look at the NON-CONVENTIONAL SOURCES of energy. With regard tothis idea we have designed an Electrical vehicle that runson solar energy. The vehicle designed is a three wheel

drive and can be used for shuttle and short distances. Asthese vehicles form the future of the automotive industry,we need to concentrate on improving their design andmaking them cost effective. This vehicle is an initiative inthis direction.

AI. BASIC FUNCTIONAL DIAGRAM

Fig. 1 Basic block Diagram Representation of Solarvehicle

The above diagram gives an overview of the working ofsolar vehicle. Sun is the main source of energy for thevehicle. Energy from Sun is captured by the solar panelsand is converted to electrical energy. The electrical energythus formed is being fed to the batteries that get chargedand is used to run 36 V DC high torques DC series motor.The shaft of the motor is connected to the rear wheel of thevehicle through chain sprocket. The batteries are initiallyfully charged and thereafter they are charged by panels.This help sin completing the charging-discharging cycle ofthe batteries, which is very important for proper working ofbatteries.

BI. BASIC CIRCUIT DIAGRAM

The connections are made from battery to motor viaswitch, controller unit and the solar panel. As stated before,the motor used in this vehicle is24 V dc series motor. Thereare four terminals on motor, namely A1, A2, F1, F2, as A1,A2 are the armature terminals and they are internallyshorted. All the connections are made keeping the DPDTswitch at the center. The either connections on DPDTswitch are made for forward direction motion of motor andthe next side of DPDT switch is made for reverse directionof motor. The motor will work as these which is kept ineither of the directions as per requirements. The A2 is

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directly taken from battery to the positive side of DPDTswitch and F2 is taken via controller unit to the negativeterminal of switch. For the DPDT the centre terminals aregiven the upper side as positive from battery and the loweras the negative from battery. The controller unit used hereis a high resistance setup box which can withstand up to thecurrent of 60amps. Now the A1, A2 are the internallyshorted terminals of the motor. Thus either of the one is themain and another one is the dummy. In case of our motorthe A1 terminal is dummy and A2 is the main terminal.Thus all connections are made keeping A2 as the mainterminal.

Fig.2: Basic Circuit Diagram

In the switch the A2 and F1 are the terminals that areresponsible for the reverse motion of motor. All theconnections are directly to switch, A2 is given to positiveandF1 given to the negative of switch.

IV. COMPONENTS USED

Various types of electrical components were used formaking the solar powered vehicle. A list of thesecomponents used with their range and the specificquantities that were required for making the solar vehicle isgiven in the following table.

A. Components used Range Quantity

Solar module Solar module

Motor Power Rating 1.5KW

Rated Current 41.6Amp

Rated Voltage 36v

Rated RPM approx3000

Torque 31.36N-m

Shaft Diameter 1.5"


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B. DETALING OF WIRELESS KILL SWITCH

A kill switch, also known as an emergency stop or e-stop, is a safety mechanism used to shut off a devicein an emergency situation in which it cannot be shutdown in the usual manner. Unlike a normal shut-down switch/procedure, which shuts down allsystems in an orderly fashion and turns the machineoff without damaging it, a kill switch is designed andconfigured to a) completely and as quickly aspossible abort the operation, even if this damagesequipment and b ) be operable in a manner that isquick, simple be obvious even to an untrainedoperator or a bystander. Many kill switches feature aremovable barrier or other protection againstaccidental activation. Kill switches are also used onland vehicles as an anti-theft system and as anemergency power off. Such devices are often placedin bait cars and configured so that observing policecan trigger the switch remotely.

Fig.3: Cutoff Circuit

C. SOLAR PANEL DETAILS

Solar cells, also called photovoltaic (PV) cells by scientists,convert sunlight directly into electricity. PV gets its namefrom the process of converting light (photons) to electricity(voltage), which is called the PV effect. The PV effect wasdiscovered in 1954, when scientists at Bell Telephonediscovered that silicon (an element found in sand) createdan electric charge when exposed to sunlight. Soon solarcells were being used to power space satellites and smalleritems like calculators and watches. Today, thousands ofpeople power their homes and businesses with individualsolar PV systems. Utility companies are also using PVtechnology for large power stations. Solar panels used topower homes and businesses are typically made from solarcells combined into modules that hold about 40 cells. Atypical home will use about 10 to 20 solar panels to powerthe home. The panels are mounted at a fixed angle facingsouth, or they can be mounted on a tracking device thatfollows the sun, allowing them to capture the mostsunlight. Third-generation solar cells are being made froma variety of new materials besides silicon, including solarinks using conventional printing press technologies, solar

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dyes, and conductive plastics. Some new solar cells useplastic lenses or mirrors to concentrate sunlight onto a very

small piece of high efficiency PV material. The PV materialis more expensive, but because so little is needed, thesesystems are becoming cost effective for use by utilities andindustry. However, because the lenses must be pointed atthe sun, the use of concentrating collectors is limited to thesunniest parts of the country.

V. WORKING OF THE VEHICLE

The solar module mounted on the top of car is used tocharge the batteries via charge controller. A solar module isused with output ranging from 36V to 40V at STC. Thebatteries are initially fully charged and then they areconnected to solar module for charging. This helps to keepthe battery charged always. This is also done as theefficiency of solar module is only 19%.Thus under thiscondition the battery gets fully charged again within 3hrs-3.5hrs. Thus to keep the full sine wave of charging thistime lap is made. The maximum solar radiations areobtained between morning10am to evening 3:30pm. Hencethe panel is so mounted that maximum output may beobtained. As the supply is given through DPDT switch themotor takes a high starting current to propel the wheel tomove in forward direction. On start the load on motor isnearly 250kg including the weight of person driving it. Themotor after start acquires the maximum speed of 20kmphto 30kmph. The batteries get charged always from the solarpanel and so it provides the continuous run for the vehicle.Motor must be started on top most gear so as to getmaximum torque and speed to lift the full load. The speedmay be varied later according to the driver’s requirements.As the speed varies the load current also varies. So thespeed variation must be low to keep battery alive formaximum duration of time. For stopping the motor, thespeed control switch should be brought to minimum gearand then switch should be open; thereafter the mechanicalbrakes should be applied. The disc brakes can be appliedinstantly during emergency but this should be avoided asthis could damage the motor and also produce unnecessaryback emf. The average battery back-up is around fourhours.

VI. ADVANTAGES OF THE VEHICLE

The solar vehicles are the future of the automobileindustry. They are highly feasible and can bemanufactured with ease. The main advantages of a solarvehicle are that they are pollution less and are veryeconomical. Since they cause no pollution they are veryeco -friendly and are the only answer to the increasingpollution levels from automobiles in the present scenario.By harvesting the renewable sources of energy like thesolar energy we are helping in preserving the non-


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renewable sources of energy. The other main advantagesof the solar vehicle are that they require less maintenanceas compared to the conventional automotive and are veryuser friendly.

VII. CONCLUSION

The solar vehicle solves many problems related to theenvironment and is the best pollution free method. We needto make use of them so that we can reduce our dependenceon fossil fuels. Solar vehicles do have some disadvantageslikes mall speed range, initial cost is high. Also, the rate ofconversion of energy is not satisfactory (only 17%). Butthese disadvantages can be easily overcome by conductingfurther research in this area; like the problem of solar cellscan be solved by using the ultra-efficient solar cells thatgive about 30 -35% efficiency. As this field of automobileswill be explored the problems will get solved. The solarautomobiles have a huge prospective market and we shouldstart using them in our day to day life. We are making asolar vehicle prototype as our project and the vehicle willbe successfully running on solar power. The picture of ourcad designed vehicle is shown below.

ACKNOWLEDGMENT

This paper is based on a real time project carried out by the students ofLINGAYAS University, Faridabad. The vehicle was made possible with thehelp and assistance provided by Mr. ANUKUR KASYAP and MS. MAMATA,Assistant professors, LINGAYAS University, Faridabad. The project wastaken by a team of named TEAM SHAKTHI of 20 members named saisrinivas sajja, karkthik,vinay,vivek,sanath,chakreesh,Deepak,suman,sumanth,nuttaki,suman th, sheril, sharath, pavan, akhil,rishi,puneender,vinyas, ujjwal,fizan,mohith.

REFERENCE

[1] “SOLAR VEHICLES AND BENEFITS OF THE TECHNOLOGY”, by John Connors, ICCEP paper 2007.

[2] www.electricvehicle.com for the electrical design of the car and to know the technologies used in previous cars.

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Imperial International Journal of Eco-friendly TechnologiesVol. - 1, Issue-2(2017), pp.72-76

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DESIGN AND OPTIMIZATION OFPASSENGER ATV KNUCKLE

Vishnu Vardhan Y*, D. Vijay Reddy**, K. Siva Sankar Reddy***, E. Bhargav Sai****

K L University, Vijayawada, Mechanical Engineering,

[email protected],[email protected], [email protected],[email protected]

I. Introduction to steering knuckleABSTRACTThe weight of the vehicle is going to increase due to theadditional luxury and the safety features. Increase inthe weight of the vehicle effects the overall performanceof the vehicle and in the fuel efficiency, so the weight ofthe vehicle is to be reduced and optimized to restore theperformance of the car. Therefore in today’s automobileindustries there is need of reducing in the weight of thevehicle.In a vehicle industry the presence of the variablephysical properties and manufacturing process,determine the approach are unable to take into accountthere are variable manufacturing techniques which willlet us manufacture the component not be in anoversized structure. The necessity of assessing theparticular component to a robustness requires a certainprocedure and process to be followed based upon theoptimization techniquesIn General Steering knuckle is one of the importantcomponent of vehicle which links suspension system,steering system, wheel hub and braking to the chassis.We have identified the various problems in steeringknuckle and optimized the design of it based on thedurability and design optimization through Ansys.Steering knuckle is a crucial component in a car, itsmain function is to bare load and produce steeringeffect and which support the body weight, to withstandthe front and back brake braking torque so on. So thedesign of the steering knuckle plays an important roleand it is strictly seen. According to the design of theknuckle it is divided into variouscategories and design is based on it some of the varioustypes are Heavy-duty vehicle knuckle, light-weightvehicle knuckle, mini car knuckle, passenger carknuckle, midsized car knuckle. The targeted massreduction in this project is to reduce the weight of thesteering knuckle to half of its weight withoutcompromising on the structural strength.

Steering knuckle is the crucial component in a car it is theonly component which links suspension system, steering,wheel hub and the brake to the chassis. It undergoesvarious loads in different situations, without affecting thevarious vehicle performance characteristics. Knuckle is thepivot point which if free to rotate in a single point axis andwhich links the steering mechanism of the car or othervehicle Knuckle is important component that transfers allthe forces that are produced at the tie road to the chassisthrough the suspension system. Design of the steeringknuckle is based on the various force acting on it and theforcing acted due to road on the wheel when the vehicle isin dynamic. Design also includes various constraints thatare related to the knuckle such as breaking system, steeringand drive train

The steering knuckle is a joint on our car which allows thesteering arm to produce turning effect in the front wheels.The forces applied on the steering knuckle are of cyclic andthe steering arm is used to turn the front wheels to right/left and to centre according to the driver comfort andnecessity.In the present markets steering knuckle is available in widevariety of sizes and shapes and their design is varied uponvarious usage and load constraints and even fit, suspensiontypes. There are to main parts in the steering knuckle onecomes with spindle and the other is hub.

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mailto:[email protected]


In this project we have selected steering knuckle as our main part of study with mass or weight reduction became an important issue in the present car manufacturing industry which would ultimately lead to the steering efficiency and total mass/weight reduction of car and have a great impact on the fuel efficiency and driver comfort Weight of the steering knuckle id being optimized by using the various processes and techniques like taking advantagesin the material and material properties, design of the component and analysis done on the material and fabrication techniques etc., in this optimization process we have subjected the knuckle to various cyclic loads which it will experience during its life time and considered various loads which causes failure in the component there for design of knuckle plays an important role in the development cycleIn present day automobile manufactures they are mainlyconcentrating on the luxury vehicles and sport cars whichincreases the safety and comfort to the end customer. Often,they reduce in the weight of the components likesuspension and weight of body and various components ofthe car will ultimately increase in the overall performanceof the car and increases the stability of the vehicle.Therefore design optimization should be implied to obtainthe minimum weight with the feasible performance of thevehicle based upon the considerable constraints, designboundaries and design uncertainties, such as designclearance and material defects.

AI. Literature survey

1. Workshop report published by the United Statesgovernment (Feb 2013) focused on the development of thelight weight vehicles and technology gap and also set a goalfor optimizing the weight of the chassis and suspensionsystem by 25% by the year 20202. Studied chapter Millikan and Millikan book for race cardynamics and referred the design constraints and geometryof the steering knuckle

3. A report published by Society of Automobileengineering in the year 2010 by Aditya Bhatt inthe name of kinematic analysis of formula SAEsuspension in view of optimizing the steeringgeometry in the race car

4. Raj Kumar Roy in year 2008 in the name of focuson the recent approaches to automating themanual optimization process and the challengesthat it presents to the engineering community.

5. prof. R. L. jhala et. Al (2009) asses fatigue lifeand compares the fatigue performance of thesteering knuckle made from three materials ofdifferent manufacturing performance.

There are four declines for the optimizing procedure: Topology optimization: In the optimization process it gives the optimum material layout according to the design and load constraints


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Shape optimization: this optimization gives the optimumfillets according to the design and the load constraints.

Size optimization: The aim of applying this optimumprocess is to obtain the optimum thickness according to theload and shape of the component

Topography: it is an advanced method for theoptimization in which a design region is identified and thevaried shape will be generated and reinforcements.

BI. Methodology

The stiffness and the normal mode analysis of the steeringknuckle is obtained using the finite method analysis byusing the HYPER MESH and in ANSYS WORK BENCHby giving the necessary boundary conditions by using thesolvers like RADIOSS. Weight optimization is done byusing the solver like OPTISTRUCT. The weight reductionis done using topology optimizing techniques by meetingthe necessary constraints like strength, stiffness, and thevibration target and the corresponding analysis is also doneon the optimized component. The design direction given bythe OPTISTRUCT is used to do the design modificationsand with few iterations, the optimized design satisfying allthe constraints given and the load constraints which it willexperience during its life cycle The design validationprocedure is followed in this criteria and performed thelinear static analysis and the normal mode analysis usingthe RADIOSSThe following flow diagram gives approach to theoptimized component

73IV. Designing a cad model

A cad model of the steering knuckle is designed in 3D byusing solid works software. It consists of all the necessarydimensions and points like calliper mounting points stubhole, steering tie rod mounts, and upper and lower-armmounting points, design of the steering knuckle is mainlydepends upon suspension geometry and steering geometry.

V. Material selection procedure

For the manufacturing of the steering knuckle there arevarious materials are used according to the necessity, loadconstraints and application and application in general greycast iron and forged steel is used but in contrast to the allconsiderations we have used aluminum (Al6083) which isone of the light weight material and having same properties

VI. Meshing

Designed CAD model of the steering knuckle is convertedinto IGES file and this model is imported into HYPERMESH and this model id meshed by selecting or giving finemesh for the better Quality and for the better results.


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Meshing of model

Element Tetras and traisNo : of Elements 39553

Nodes 9618Material Al 6083

Basic geometry is then simulated by giving actual loadingconstraints. The load constraints obtained from dataacquisition system is given below.

Braking stress=102.95mpa

After the completion of the analysis max displacement isobtained at brake mounting points and the maximum stressis obtained in the junction point of brake calliper andsuspension mounting pointMaterial density distribution is observed for finding thelow stress area so that we can modify the design / geometryof the component by removing the material that are excesswithout any load. For the removal of the material ofcomponent we have to follow some manufacturing aspectsand functional constraints. Feasibility of the machining andmanufacturing is to be verified at the time of materialremoval process.

74After removal of the material in the unnecessary regionswhere stress factor of the material is very low component is

once again analysed for same loading conditions andobserved for minimum displacement and stress pattern.

Braking Deformation=0.151mm

Bumping Deformation=0.020148

Bumping stress=61.99mpa


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Cornering stress=24.455mpa

VII. Observations

It is clearly seen that that max displacement and stresspatterns are same in both the cases, and it is also seen thatmaximum stress is also obtained in the same region as inthe previous condition. So, properties of the twocomponents before and after optimization do not changeand the values are safe for given constraints.

VIII. Result

Initial model of steering knuckle has its maximum stressvalue of 102.95 MPa. After applying optimizationtechnique it is seen that there is mass reduction in weightof knuckle by 40% when compared to the initial designand conventional knuckles which are available in thepresent day market.

Initial Optimized %design Design Reductio

nDisplacement 0.12mm 0.151 mmStress 95 MPa 102.95 MPa

Cornering Deformation=0.061729Mass 3 Kg 1.2 Kg 40 %

IX. Conclusion

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By using the topology optimization technique we haveobtained weight optimization of about 40% when comparedto conventional knuckles which are available in present daywithout any change in the material properties and loadconstraints which ultimately lead us in the reduction in thecost of manufacturing cost, as well as, improving in thesteering effort, vehicle stability, and ultimately lead todecrease in the fuel consumption

REFERENCES

[1] Borns, R. and Whitacre, D., "Optimizing Designs ofAluminium Suspension Components Using anIntegrated Approach," SAE Technical Paper 2005-01-1387, 2005,

[2] Krishna, M., "Finite Element Shape Optimization of aSteering Knuckle for a Heavy Truck–A Case Study,"SAE Technical Paper 2001-01-0634, 2001, doi:10.4271/2001-01-0634

[3] Nohara, S., Barcha, C., Ogassawara, F., and Peixoto, V.,"Structural Optimization of Knuckle for Mac Pherson toImprove Mass Reduction and Cost," SAETechnical Paper 2012-36-0395, 2012, doi:10.4271/2012-36-0395

[4] Kim, M., Lim, T., yoon, K., Ko, Y. et al., "Developmentof Cast-Forged Knuckle using High Strength AluminumAlloy," SAE Technical Paper 2011-01-0537, 2011,doi:10.4271/2011-01-0537.

[5] Felske, W., "Cast Steering Knuckle Finite Element andLaboratory Strain Analysis," SAE Technical Paper770613, 1977, doi:10.4271/770613.

[6] Viraj Rajendra Kulkarni, Amey Gangaram Tambe.“Optimization and Finite Element Analysis of Steering Knuckle” Altair hyperworks technical paper – 2013

[7] Purushottam Dumbre, Prof A.K.Mishra, V.S.Aher,Swapnil S. Kulkarni – “structural analysis of steeringknuckle for weight reduction” - International Journal ofAdvanced Engineering Research and Studies E-ISSN2249–8974

[8] Rajeev Sakunthala Rajendran, Subash Sudalaimuthuand Mohamed Sixth “Knuckle Development Processwith the Help of Optimization Techniques” AltairTechnology Conference, India,2013.

[9] K. S. Chang and P.S. Tang “Integration of Design Andmanufacturing of structural shape optimization”Advances in engineering software32 (2001) 555-567

[10] Patel Niral and Mihir Chauhan “FEA and TopologyOptimization of 1000T Clamp Cylinder for InjectionMolding Machine” Procedia Engineering 51 (2013 )617 – 623.

[11] Prof R. L. Jhala, K. D. Kothari and Dr. S.S. Khandare“Component Fatigue Behaviors And Life Predictions OfA Steering Knuckle Using Finite Element Analysis”International Multi Conference of Engineers and Computer Scientists 2009 Vol II


IIJET[12] . RajkumarRoy, Srichand Hinduja and Roberto Teti

“Recent advances in engineering design optimization:Challenges and future trends” CIRP Annals –Manufacturing Technology 57 (2008) 697–715

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SOLAR PANEL PARAMETERS MONITORING USING ARDUINO

SHAHEEN RASHEED*, KARTHIK SS*

Electronics and Communication Engineering, Kpr Institute of Engineering and Technology

* [email protected], **[email protected]

I. INTRODUCTION

There are Power Stations for Maintaining or Monitoringthe Power Circuits or Parameters related to Solar Panel.Parameters like Voltage, Temperature, Light Intensity andCurrent, which are important to monitor. The Monitoringof these parameters are also important in Households too.So, here we discuss on how to Monitor Solar PanelParameters.

AI. OBJECTIVE

In this circuit all the parameters are in the analog form. Weneed to only convert them in Digital Form and displaythese Digital values on the LCD. Some additional circuitsare also required for proper Measurement.

BI. ARDUINO

This project will help you get started with the Arduino,including a description of the different types of Arduinos,how to download the Arduino software developmentenvironment, and describe the different shields that areavailable for the Arduino. The Arduino is an open-source,single-board microcontroller that you can use for manydifferent applications. It is arguably the easiest and leastexpensive microcontroller option for hobbyists, studentsand professionals to develop microcontroller-basedprojects. Arduinos use either an Atmel AVR or Atmel ARMmicrocontroller chip, and some versions have a USBinterface. They also have six or more analog input pins andfourteen or more digital input/output (I/O) pins that areused to connect sensors, actuators, and other peripheralcircuits to the microcontroller.

A. TYPES OF ARDUINO BOARDS

There are many different types of Arduinos available,as shown in the table below, each with its own featureset. They differ with regard to processing speed,memory, I/O ports, and connectivity, but their basicfunctionality is the same.

Arduino Uno Arduino Leonardo Arduino Due

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Arduino Yún



Arduino Tre Arduino Micro Arduino Robot Arduino Esplora Arduino Mega Arduino Mini LilyPad Arduino Arduino Nano Arduino Fio Arduino Pro Arduino Ethernet

B. SOFTWARE

(IDE)

The software used to program the Arduino is called theIntegrated Development Environment (IDE). The IDE is aJava application that runs on many different platforms,including PCs, Macs, and Linux systems. It is developedfor beginners who are not familiar with programming. Itincludes a code editor, a compiler, and an up loader. Alsoincluded are code libraries for using peripherals, such asserial ports and various types of displays. Arduinoprograms are called "sketches," and they are written in alanguage very similar to C or C++.

C. USB CABLE

Most Arduinos connect to a host computer via a USBcable. This connection enables you to upload sketches toyour Arduino as well as provide power to the board.

D. PROGRAMMING

Programming an Arduino is easy: you use the IDE codeeditor to write the program and then compile and upload itwith a single click.An Arduino program includes two main functions:

1. setup()

2. loop()


IIJET

You use the setup () function to initialize settings for theboard. This function runs only once when the board ispowered on.The loop () function is executed after setup () completes,and unlike the setup () function, it runs continually.

E. PROGRAMMING FUNCTIONS

Here are some of the most commonly used functions inArduino programming:

pinMode - sets the pin mode to either INPUT or OUTPUT.

analogRead - reads an analog voltage from an analog input pin.

analogWrite - writes an analog voltage to an analog output pin.

digitalRead - reads the value of a digital input pin. digitalWrite - sets the value of a digital output pin

to either HIGH or LOW. Serial.print - prints data to the serial port as

human-readable ASCII text.

F. ARDUINO LIBRARIES

Arduino libraries are collections of functions that allowyou to control devices. Here are some of the most widely-used libraries:

GPS library LCD library Servo library SD library Robot_control library Robot_motor library Ethernet library Wi-Fi library Stepper library SPI library EEPROM library Software Serial library GSM library Steps for setting up Arduino

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1. First, install the IDE software. You can download the IDE from the Arduino website .

2.Install the software on your PC.

3. Now run the Arduino IDE .exe file. It has a followinglayout:

4. Write your program using the code editor andupload it to the Arduino. To do this, you need toconnect the Arduino to your computer using aUSB cable.

5. In the IDE, select the type of Arduino you are using from the Tools -> Boards menu.

6. Now verify your code by clicking the ‘tick’ iconat the top of the IDE window, then click theadjacent ‘right’ arrow to compile and upload thecode to your Arduino.

Note: You may have to install drivers if your system does not detect the Arduino.

G. ARDUINO SHIELDS


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Arduino shields are board that plug into the Arduino to allow you to connect peripheral devices, sensors, and actuators to the Arduino. Below are some popular shields:

GSM Shield Ethernet Shield WiFi Shield Motor Shield Proto Shield Joystick Shield Bluetooth Shield Xbee shield

H. COMPONENTS AND ACCESSORIES

Below is a list of all the components and accessories commonly used with an Arduino to develop projects:

Breadboard USB cable 9V Battery LEDs Push Buttons Capacitors Voltage Regulators Sensors (IR, temperature etc) Jumper wires Resistors Potentiometer Motors (DC, Servo, BLDC) LCD Hex keypad Arduino shieldsI. VOLTAGE MEASUREMENT

Voltage Measurement of the Solar Panel is very easy whichis up to 5 volts. But if we want to measure more than 5volts then we have to use some additional circuitry likeVoltage Divider. This circuitry changes according toVoltage, which means How Much Voltage we have toMeasure. Let us suppose if we want to measure 5 volts,then there is no need for any Additional Circuitry. Justconnect the solar panel Output Voltage to Analog pin ofArduino and convert that in Digital and Display result onLCD or Computer. And suppose if you want to measure upto 10 volts then you have to use the given circuitry

For measuring Voltage we have to follow the givenFormula

Voltage= (Analog value / resistor factor) * referenceVoltage

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http://arduino.cc/en/main/software

http://arduino.cc/en/main/software

WhereAnalog value= Analog output of Voltage divider

Resistor factor= 1023.0/(R2/R1+R2)

Reference Voltage= 5 volts

R And let suppose:

R1= 1K

R2=1K

Resistor factor= 1023.0 * (1000/1000+1000)

Resistor factor=1023.0 * 0.5

Resistor factor= 511.5 for up to 10 volts and for more see given table.


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through some calculation we will get the Light IntensityResult.

Here we are going to show you how to do this:

For this we have to use LDR , (Light Dependent Register)which is very common and easily available in the market.

Now you can see the Circuit Diagram for Light IntensityMeasurement part

Here we are using a 3.3K ohm resistor and a LDRconnected with each other and middle points is used asoutput. As light falls on LDR, resistance of LDR decreases,due to which Analog Voltage is generated, later apply thisVoltage to Arduino.

Relation between RL (LDR) and Light Intensity (Lux) isgiven below:

RL=500/Lux

Output Voltage of this circuit can be calculated by usinggiven formulaVout= 5 * RL / (RL+3.3)Where RL is Load Resistance (LDR Resistance variesaccording to light intensity).Now by using given formula we can calculate Light intensity in lux ( where lux in unit of light intensity) Lux= (2500 / Vout – 500) / 3.3

IV. LIGHT INTENSITY MEASUREMENT

Light Intensity is also easy to execute in the project like theVoltage Measurement. For Light Intensity first we have to useVoltage divider and then measure the Voltage. Later

V. TEMPERATURE MEASUREMENTFor Measuring Temperature here we have used lm 35 thatis gives 10 mV for every 1 degree Celsius. Circuitry issimple for this.

80

http://www.engineersgarage.com/electronic-components/ldr-light-dependant-resistor

By using given formula we can calculate Temperature inDegree Celsius:

Temperature=Analog value*(5.0/1023.0)*100;

Where, 5 is reference voltage

A. COMPONENTS USED

1. Arduino2. Solar Panel3. LM354. LDR5. 16x2 LCD6. Resistors7. Connecting wires8. Power supply

VI. PROGRAM#include<LiquidCrystal.h> #define sensor A0 #define VOLT A1 #define LUX A3 LiquidCrystallcd (2, 3, 4, 5, 6, 7);float Temperature, temp, volt, volts,lux,Temp; int temp1, value;byte degree[8] =

0b00011,0b00011,0b00000,0b00000,0b00000,0b00000,0b00000,0b00000

;


IIJET

void setup()

lcd.begin(16,2);lcd.createChar(1, degree);

Serial.begin(9600);

lcd.setCursor(0,0);

lcd.print(" Soler Energy ");

lcd.setCursor(0,1);

lcd.print(" Measurement ");

delay(2000);

lcd.clear();

lcd.setCursor(0,0);

lcd.setCursor(0,1);

lcd.print("kpriet");

delay(2000);

lcd.clear();

void loop()

/*---------Temperature-------*/ float

reading=analogRead(sensor);

Temperature=reading*(5.0/1023.0)*100;

delay(10);

/*---------Voltage----------*/

temp1=analogRead(VOLT);

volts= (temp1/511.5)*5;

delay(10);

/*-----Light Intensity------*/

value=analogRead(LUX);

volt=(value/1023.0)*5;

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lux=((2500/volt)-500)/3.3;

http://www.engineersgarage.com/electronic-components/16x2-lcd-module-datasheet

http://www.engineersgarage.com/electronic-components/lm35-sensor-datasheet

http://www.engineersgarage.com/microcontroller/arduino-projects

delay(10);

------Display Result------*/

/* lcd.clear();

lcd.setCursor(0,0);

lcd.print("T:");

lcd.print((int)analog_value);

lcd.write(1);

lcd.print("C");

lcd.setCursor(8,0);

lcd.print("V:");

lcd.print(volts);

lcd.setCursor(0,1);

lcd.print("Intens: ");

lcd.print((int)lux);

lcd.print(" Lux");

Serial.println((int)Temp);

Serial.println(volts);

Serial.println((int)lux);

delay(500);

VII. CONCLUSION


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[4] "Programming Arduino Getting Started with Sketches". McGraw-Hill. Nov 8, 2011. Retrieved 2013-03-28

[5] Make: Electronics (Learning by Discovery); Charles Platt; 352 pages; 2009; ISBN 978-0596153748.

[6] How Solar Cells Work". HowStuffWorks. Retrieved 2015-12-09.

We have presented work on design and development ofsolar panel parameter reading using arduino forenviornmental monitoring, the node is enough to provideinformation about enviornment parameters such astemperature,current,voltage,light intensity.

REFERENCES

[1] "Arduino - Introduction". arduino.cc.[2] "Blink Tutorial". Arduino.cc.[3] "The arduino source code". The arduino source code.

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https://github.com/arduino/Arduino

http://arduino.cc/en/Tutorial/Blink

http://arduino.cc/en/guide/introduction

http://science.howstuffworks.com/environmental/energy/solar-cell2.htm

https://en.wikipedia.org/wiki/Special:BookSources/9780596153748

http://www.amazon.com/Programming-Arduino-Getting-Started-Sketches/dp/0071784225/ref=sr_1_1?s=books&ie=UTF8&qid=1364494138&sr=1-1&keywords=arduino+sketches

http://www.amazon.com/Programming-Arduino-Getting-Started-Sketches/dp/0071784225/ref=sr_1_1?s=books&ie=UTF8&qid=1364494138&sr=1-1&keywords=arduino+sketches


IIJET

SOLAR POWERED VECHILETeam- Arka Shakata

Abstract

The renewable energy is vital for today’s worldas in near future the non-renewable sources thatwe are using are going to get exhausted. Thesolar vehicle is a step in saving these non-renewable sources of energy. The basic principleof solar car is to use energy that is stored in abattery during and after charging it from a solarpanel. The charged batteries are used to drivethe motor which serves here as an engine andmoves the vehicle in reverse or forwarddirection. The electrical tapping rheostat isprovided so as to control the motor speed. Thisavoids excess flow of current when the vehicle issupposed to be stopped suddenly as it is innormal cars with regards to fuel. This idea, infuture, may help protect our fuels from gettingextinguished.In this report, the construction and working ofa solar vehicle with minimum complexity incharging the batteries is shown. This report alsocontains the technical and physical details of allthe equipment that are used in the constructionof the vehicle. The selection of both electricaland mechanical components is one of the mostimportant aspect of a solar vehicle which iscovered briefly in this report. The electricalequipment in the vehicle includes solar panels,solar charge controller, BLDC motor, motorcontroller, batteries and speed control while themechanical apparatus includes a simplesteering system, braking system, suspensionsystem, materials to be used and the chain drivesystem. The most common practical problemsand troubleshooting are covered along withprecautionary measures. This report isconcentrated primarily on the electrical themeand the mechanical systems are only briefedwhich are mandatory in any vehicle. Some ofthe flexible changes in thevehicle according to the individualrequirements are briefed in the chain drivesystem. The simplest of mechanical parts areused in the construction and their details arefurnished in the report. The aim of this report isto construct a solar vehicle which is economicaland simple in construction without anycomplexity in charging the batteries. The aim ofthe paper is reached in part.

Index Terms— photovoltaic cell, BLDC motor,motor controller, simulation

I. INRTODUCTION

In this world of fuel and gas powered vehicles,there is an increasing need for reduction ofenvironmental pollution by limiting the release ofgreenhouse gases into the environment. Everyvehicle which uses engines and fossil fuels topower them emit carbon monoxides when the fueldoesn’t burn completely, hydrocarbons from theexhaust and harmful nitrogen oxides. Whenhydrocarbons and nitrogen oxides combine insunlight, they produce ozone. Ozone in theatmosphere closer to surface contributes to smogand causes respiratory problems. Air pollutantsemitted from cars contribute to problems such ascancer, asthma, heart disease, birth defects and eyeirritation. Keeping in mind the disastrous effects ofthe poisonous gases emitted due to vehicles, thebest possible solution is to replace these vehicleswith eco-friendly electric vehicles. Solar electricvehicle is one of the fancy ideas in the modern dayworld. The present day world’s best idea ofreducing the pollution and use of fossil fuels. Bymaking use of available technology with changedspecifications and by positioning the componentsin appropriate places the performance of thevehicle can be improved. There are many ways ofbuilding an electric vehicle. Some of the ways inwhich this problem is addressed is by charging thebatteries using electricity in residences and placingthem in vehicles which is a tiring job as thebatteries are heavy and the user is paying for thecharging of batteries. Charging the batteries usingsolar panels which are kept in an appropriate placeand then using them in vehicles is a debatable ideaconsidering the weight of the batteries and thepossibility of unavailability of solar panels at thedestination. Directly using the solar panels on thevehicle to run the motor is a limited approach as alarge number of panels are required to run a highcapacity motor and the vehicle stands constrainedto work only when the solar panels are producingsome power. Considering all these, this reportconcentrates on using solar panels on the vehicle tocharge a high capacity battery which can be used atall times of the day and night which can also behelpful for long journeys.

AI. CIRCUIT DESIGN ANDSIMULATION

The electrical components and the electrical circuit design are the most important parts of the solar

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IIJETvehicle. The design is shown in the fig.1.1. Thesolar panels form the first part of the electricaldesign of the system. They are to be mounted ontop of the solar vehicle where the sunlight is largelyconcentrated on. The solar panels are connecteddirectly to the solar charge controller which ismanufactured according to the requiredspecifications. The solar charge controller uses itsfirst two ports for intake of power from the solarpanel which is stored in the batteries. The chargeproduced by the batteries to run the motor iscontrolled by the solar charge controller. The motorcontroller is connected to the solar chargecontroller. While the solar charge controllerregulates the power with which the motor runs, themotor controls the working of the BLDC motor.The motor controller is also provided with auxiliaryconnections such as speed control of the motor,forward and reverse switch, Lights and horn. Theconnection between every two components isprotected by using fuses or MCBs. Although it isnot mandatory to use LED detection for everyconnection, it is highly recommended to use bothfuses and LEDs between batteries and solar chargecontroller and also between BLDC motor andmotor controller. The wiring of all electriccomponents should be done properly to ensuresafety and for the ease of controlling them. Thecopper wires are suggested for the wiring as theyhave one of the highest electrical conductivity ratesamongst metals and have high negative coefficientof temperature, hence copper is more preferablethan aluminium as our wiring material. In Indiawire selection is done using standard wire gauge(SWG) system. Since our max current flowing inthe circuit is 40 A (considering starting current ofthe motor) selection of 25 mm2 area of section ofthe copper wire is recommended.

.

Fig. 1: Electric circuit Design

Swg Dia(mm)Area(m

Ω/km ampsm2)

4 5.826 26.7 0.646 75

Table 1: Specifications of the wires used

The solar panels are designed in the Simulink witha capacity of 600W. The capacity of the solarpanels can be increased or decreased by addition orsubtraction of the solar panel subsystems in thecontrol system. The subsystem of photo voltaic cellis shown in the fig.2. A constant input of 1000 anda ramp input of slope 6 are given as input to everysolar panel module in the subsystem. The outputsof these subsystems are voltage (Vpv) of photovoltaic cell and power (Ppv) of photo voltaic cell.All the outputs of the single photo voltaic cell aresummed up to form the desired quantity. Photovoltaic cells are constant with respect to voltage sothe I-V characteristics and P-V characteristics ofthe photo voltaic cells are considered as the proofof proper functioning of the photo voltaic modulein the sub system. Photo voltaic cell is a practicalsource. As every practical source has a drop due tothe shunt resistance, the photo voltaic cells has adrop in both current and voltage. The results can beseen clearly considering the I-V characteristics andthe P-V characteristics. The current has a drop dueto the shunt resistance and the voltage has a dropdue to the series resistance. These forms the I-Vcurve (Y axis = current and X axis = voltage) of thephoto voltaic cells which are shown in the fig.3.Similarly once the voltage and current are knownin the system, the power can be determined as theproduct of voltage and current through which P-Vcurves (Y axis = power and X axis = voltage) areobtained as shown in fig.1.5.

Fig.2: Sub system of photo voltaic cell module

As physical quantities like sunlight, temperature,radiation etc. cannot be shown in MATLABsoftware, the photo voltaic cells also cannot beshown. Only if these curves are obtained, the subsystem can be used as a photo voltaic cell inSimulink (MATLAB). Different curves areobtained for different positions of sun but it isessential for us to maintain at a point wheremaximum power can be derived. This is achievedfrom the maximum power point tracking (MPPT).There are many algorithms to implement themaximum power point tracking method. Thealgorithm used in this report is the perturb andobservation method. This is the best controlstrategy for the MPPT technique. To know moreabout the perturb and observation method refer tothe material mentioned in the references. Taking

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IIJETthe voltage and current values from the photovoltaic cell, a MPPT with desired quality can beordered. At the same time there is no requirementof any other converter as the load itself is dc(BLDC motor). If an ac motor is used, additionalconverter such as an inverter should be used todrive the motor. The power from the photo voltaiccells is not sufficient to run the motor so a dc to dcconverter is to be used. It is also called as boostchopper or step up chopper. It is preferable to use abidirectional chopper as we require to both step upas well as step down. A bidirectional dc to dcchopper is used to charge the batteries. This acts asa step down chopper when charging the batteriesand as a step up chopper when the batteries aredischarging. If the maximum power point trackingmethod is used to switch on/off the chopper, weshall always be at maximum power point. In thechopper it is essential to use a MOSFET switch asthis chopper works on low voltage and highfrequency applications. The MOSFET switch is tobe commanded on when to switch on/off as only onthis command the circuit decides on voltagerequirement. Finally, to control all these we requirea closed loop controller. To control the dc motor,actual speed (fig.5) of the motor is considered.Then the reference speed (fig 6) is given as anexternal input as the speed change due toacceleration is a physical quantity which cannot beexpressed in the MATLAB software. From thecomparison of these two speeds a duty cycle isobtained. Another duty cycle is taken from theMPPT. The average of these two duty cycles isused to switch on/off the dc to dc converter. Anychange in speed is controlled through the chopper.The speed of response of the system is shown in thefig.1.8. The comparison of both the actual speed aswell as the reference speed is done and the error isfed to a PI controller. The PI controller corrects theduty cycle. Then the carrier voltage of the controlsystem and the reference voltage (constant of 400in this report) are compared and the resultant is fedto the chopper. Usually only a MPPT controller or amotor controller are used in one program in whichindividual duty cycles are considered but in thisreport both MPPT controller and motor controllerare being used in a single program so the averageof both the duty cycles must be fed into thechopper.

Fig.3: I-V characteristics of photo voltaic cell

Fig.4: P-V characteristics of the photo voltaiccell.

Fig.5: Actual speed of the motor in speed vs.time graph

Fig.6: reference speed parameter

Fig.7: Speed of response to change inspeeds.

BI. SELECTION PROCESSA. Motor

Motor is the most important part of an electricvehicle as motor is the sole machine which isrunning the vehicle. Motor being a major deviceconverting electrical energy into mechanicalenergy to bring the vehicle into motion, we need toconsider important parameters in selecting themotor those are horsepower, efficiency, life,starting torque, speed, cost, size, weight and itscharacteristics under operating conditions. In thisreport, the selection of motor is done consideringthe reduction of overall weight and cost of the

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IIJETvehicle. A brushless direct current motor is bestsuited for this type of vehicle. BLDC motor is asynchronous motor power by a dc source through aswitching power supply. The rotor of this motor is apermanent magnet synchronous motor. Althoughthere are many technical details for the selection ofBLDC motor to run the vehicle, a brief note ofavantages are as follows while the others can beviewed through the reference. BLDC motorcommutation is done based on rotor positioninformation, high efficiency as voltage drop onelectronic device is smaller than that on brushes, nomaintenance as the brushes are absent, loweracoustic noises due to absence of arcs from thebrushes to generate noise, greater dynamicresponse due to lower rotor inertia because ofpermanent magnets, smaller and lighter in weight ,better speed vs torque characteristics as there is nobrush friction to reduce useful torque, higher speedrange as no mechanical limitation is offered bybrushes or commutatotrs, better thermalperformance as only the armature windingsgenerate heat, which is the stator and is connectedto the external part of BLDC motor and longer life.Due to the above mentioned advantages the BLDCmotor is recommended in this report. Themechanical force required to move the vehicle andthe force required to move the wheel can be reviedfrom the reference. Force required to move thewheel is generated from reference. Input electricalpower is equal to sum of the output mechanicalpower and power losses due to copper winding inarmature. Field copper losses are neglected. Themathematical calculations for the BLDC motor areas follows:

Pelectrical = Pmechanical + Pcopper losses (1)

Where,Pelectrical is input electrical power in wattsPmechanical is output mechanical power inwatts Pcopper losses is copper losses i.e. I2Rlosses in watts

Pelectrical = V*I (2)

Where,

V is supply voltage in volts (48V)I is current in amps (22A)Therefore, Pelectrical = 48*22 = 1056 WLoadtorque need to be calculated to know the amount oftorque required to move the vehicle. It is alsoessential in selecting a perfect motor for the desiredqualities.

Tload = F*r*µ

Where,

Tload is load torque in N-m F is the force requiredto spin the wheel in Newton =251.40N (from forceequation)

R is the radius of the wheel in meters = 5.5inches = 0.1397m

µ is the coefficient of friction = 0.5

Therefore, Tload = 251.40*0.1397*0.5 = 17.56N-m

Considering the BLDC motor with torque greaterthan or equal to the load torque (Tload) with anoutput speed of 300 rpm and output torque ofabout 17.56 N-m.

B. Motor controller

Motor controller as explained in the MATLABsimulation in this report is nothing but a closedloop system which is used to control the motorspeeds, current flowing through the motor,switching on/off the chopper through MPPTcontrol and auxiliaries. A detailed picture of amotor controller is given in fig.8. Motor controlleris an electronic circuitry which controls the speedof the motor by increasing/decreasing thepotentiometer. Demagnetization of permanentmagnets can be prevented by controller byavoiding overloading conditions.

Fig.8: motor controller

C. Solar panelsIn this report, the decision on selection of solarpanels is done considering the ratings of the panels,area of the panels, cost and weight of the panels.

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IIJETSolar panels are the main source of power supplyfor the vehicle. The main function of the solarpanels is that it should convert all the solar energyto electrical energy and then it is stored in thebatteries which can be furthered used. Solar panelswork on the principle of photoelectric effect.Generally panels are made of silicon which is asemiconductor. When light rays fall on the solarpanels the photons present in the light excite theelectrons of the silicon and displace them hence ahole is created and this hole is thereby filled withthe photon itself. The silicon is doped to form 2structures namely n-type and p-type. P-type ispositively charged and n-type is negatively chargedas a result an electric field is formed this fielddrives the free electrons along the semiconductor.Thus current is produced. There are three types ofsolar panels which can be considered. They aremono crystalline, poly crystalline and thin films.Almost 90% of the photovoltaic’s today are basedon variation of silicon. The main difference ispurity of silicon. More the purity the better the cellwill be converting solar energy in electrical energy.The monocrystalline silicon (mono-is) or singlecrystalline silicon. They can be recognized byeternal even and uniform coloured indicating thepurity of silicon. They are space efficient and livelonger but they are highly expensive and are onlyefficient in warm weathers. They undergobreakdown when covered with dirt or shade. Thepolycrystalline are manufactured easily by allowingliquid silicon to cool using a seed crystal of thedesired crystalline structure other methods includechemical vapour disposition (CVD). We preferthese over other due to their high efficiency andlow cost and maintenance. These panels are usedfor the solar car because of the lower heat tolerancebut these panels occupy a bit larger space whichcan be further overcome by typical arrangement ofthe panels in a particular area. So, thepolycrystalline are best suited for the solar vehicleas they are of less weight, lower cost and moreefficient. The panel’s structure and position used onthe solar vehicle mentioned in this report is shownin the fig.3.3.1. In this report six panels of 100watts each connected in series are considered forinstalling exactly on the vehicle top.

Note: Highly efficient solar energy practically doesnot depend only on the amount of heat or radiationfalling on the panels but a combination of thesealong with the atmospheric temperature and regularcleaning of the panels that helps in efficientexcitation of the silicon molecules which is theprimary cause for the generation of current.

D. Solar charge controller

Solar charge controller is considered for the need tocontrol the power from solar to battery and to increaseefficiency of the power being tracked by controllerfrom solar panel without any power losses. Solarcharge controller is a small box consisting of solidstate circuitry which is placed between a solar paneland a battery. Its function is to regulate the amount ofcharge coming from the solar panel that flows intobattery bank in order to avoid the batteries beingovercharged. It can also provide a direct connection tothe load. There are two types of solar chargecontrollers. They are pulse width modulator (PWM)solar charge controller and maximum power pointtracking (MPPT) solar charge controller. The laterforces solar panel module to operate close tomaximum power point to draw maximum availablepower. It also allows the use of solar panel modulewith higher output voltage than operating voltage ofthe battery which is not quite an advantage in a solarvehicle as there is no often change of solar panelsonce they are installed, keeping in mind the long lifetime of a solar panel (approx. 20 years). The use ofMPPT solar charge controller reduces the complexityof connections which is also not a clear advantage asa maximum of two connections in excess to thepresent is required which does not sum up to be agreat complexity. Although the use of MPPT solarcharge controller is debatable for use in a solarvehicle due to its limited advantages and higher cost,it is preferable to opt for any of the two solar chargecontrollers depending upon the individualrequirements. In this report, the MPPT solar chargecontroller is considered with 48V/40A.

Fig.10: Solar charge controller

E. Batteries

Batteries form the main source of power from thesolar panels to run the BLDC motor. When battery

Fig.9: specification of the panel is in charging mode electrical energy is converted

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IIJETinto chemical energy and while in dischargingmode chemical energy is converted into electricalenergy. The selection of batteries in this report isdone considering the need to supply sufficientpower to the motor, cost and weight of thebatteries. There are two types of batteries whichcan be chosen to run the vehicle. They are lead acidbatteries and lithium ion (cobalt) batteries. In thisreport, the lead-acid batteries are considered due tothe long discharging time, less cost and lowmaintenance. The main disadvantage of lithium-ionbatteries are expensive than the lead-acid batteriesand they don’t require regular maintenance. In thisreport four lead acid batteries of 12V and 66Ah areconsidered which are connected in series to achievea total of 48V and 66Ah. The calculations oncharging time and discharging time are the mostimportant in perfect analyzing of the working of thesolar vehicle.

F. Materials

In this report, selection of different materials forthe chassis and body works is done considering thephysical properties of some selected materials. Aright material is of utmost importance when itcomes to designing a chassis because if a materialof correct requirement is not chosen, the chassiscould break on loads leading to fatal conditions ofthe driver. The following are the importantconsiderations for the selection of proper materialfor the chassis. The material must have high yieldstrength, high machinability, easy weld ability, lowcost, light weight and high elongation at failure.Some of the materials under consideration includeAISI 4130 chromyl steel (preannealed), AISI 1020steel and Al-6063-T. The problem with AISI 4130steel was even though it gave good strength andlighter than mild steel (MS), it is expensive and noteasily weld able. Welding AISI 4130 steel is notonly costly but could not be trusted as it has to beannealed before and after welding yet givesfractures without notice. AISI 1020 steel is cheap,easily available and weld able and with somedecent specifications but when analyzed forchassis and various components like rear axle, etc.,it showed a high deflection of 2- 9mm with veryless factor of safety and addition of members toimprove strength makes the chassis heavy.Aluminum 6063-T gives enough yield strength towithstand all subjected stresses and loads. Thoughexpensive, we cannot compromise on the qualityon material for chassis and it is advised to look fora competitive price. Thus, Al-6063 satisfies allother requirements. Body Works is an importantpart of the vehicle design. External appearance isan important feature which not only gives graceand luster to the vehicle but also dominates saleand marketing of it. Each product has a definedpurpose. It has to perform specific functions to the

satisfaction of customer. The Functionalrequirement brings products and people together.However, when there are a number of products inthe market having the same qualities of efficiency ,durability and cost, the customer is attractedtowards the most appealing and economicalproduct. Three materials such as aluminum, carbonfiber and glass fiber can be considered foraesthetic considerations of the design. Aluminumshows good properties like light weight, does notrust easily, and has good machinability but iscostlier than steel and is very abrasive. Carbonfiber contains some ideal qualities like Highstiffness, high tensile strength, low weight, highchemical resistance, high temperature toleranceand low thermal expansion. However, they arerelatively expensive when compared to similarfibers, such as glass fibers or plastic fibers. Thus,budget exceeded in its place. Glass fiber is lightweight, easily moldable, easy machining, Fireresistant, Low maintenance, Anti- magnetic, goodelectrical insulator. However, it is costlier thanaluminum but fits into economic range. Selectionof glass fiber as the material for molding the bodyof the vehicle is an educated choice since glassfiber is cost effective, light weight, has goodstrength, it fits into the requirement slot formanufacturing the solar vehicle.

Fig. 11: CAD Model of Frame

G. Braking system

Braking system makes an important mechanicalentity to any automobile. An excellent brakingsystem is the most important safety feature of anyland vehicle. The main requirement of the vehicle’sbraking system is that it must be capable of lockingall wheels on a dry surface. Ease ofmanufacturability, performance and simplicity area fewimportant criteria that are to be considered forthe selection of the braking system. The two maintypes of braking systems under consideration inthis report are Drum and Disc brakes. In case ofdrum braking there is a high possibility of mud anddebris to gather in the space between the shoe andthe drum. Same problem is faced in mechanicaldisc brakes, but not in hydraulic disc brakes.Hydraulic brakes are found to be suitable for all

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IIJETtype of terrain. Since, drum brakes are of more costand they are heavier in weight which greatlyincreases the weight of solar car we can eliminateit. On the other hand, using hydraulic brakes can bean asset as it is cheap and it is readily available butthe drawback was using this system the overallweight of the solar car is increased which makes itharder for the motor (linked to battery to solarpanels) to run the car. The discs of brakes are madeof paralytic grey cast iron. The material is cheapand has good anti-wear properties. Cast steel discshave also been employed in some cases, whichwear even less and provide higher coefficient offriction; yet the big drawback in its case is the lessuniform frictional behavior. Two types of discshave been employed in various makes of discbrakes, i.e. the solid or the ventilated type.Disadvantages of ventilated type discs includeusual thickness and heavier than solid discs, In caseof severe braking conditions, they are liable towrap, accumulation of dirt in the vents, whichaffects cooling, resulting in wheel imbalance,Expensive, Difficult to turn. Turning producesvibrations which reduces the life of the disc. Any ofthese make no much difference on the solar vehiclementioned in this report as its overweight cannot gobeyond 450kgs to 500kgs. Although in the practicalversion of the solar vehicle done through this reporthydraulic drum brakes are used for the front axleand mechanical disc brakes are used for rear axlefor experimentation (fig 12) it is advisable to optfor hydraulic disc brakes for both the front andback axles as they are economical and reliable.

Fig.12: Disc with Caliper

H. Steering system

The controlling behavior of a vehicle is influencedby the performance of its steering system. The trackconsisting of sharp turns and the stability of thesystem and the response time (Feedback) are vitalfactors in deciding the vehicles’ run. The Worm andSector mechanism. Rack and pinion and the Re-circulating ball mechanism were among our optionsto go with. In this report, on consideration ofmounting ease, simplicity in design andconsidering that our vehicle is of the compactcategory; rack and pinion is chosen over the others.A practical picture is shown in the fig 13. The rack

and pinion being a simple system; can be easilymaneuvered and the defect, if any, can be spottedand taken care of. Moreover the steering wheel andother relevant apparatus are so placed in the design,for easy entering and exit of the driver. Rack andpinion steering gear being compact and lightpackage with kinematic ally stiffer characteristicscommonly employed on passenger vehicle cars.The composite error in the gear increases thetorque required to rotate the steering wheel by thedriver. Rack and pinion steering system has a veryfew moving parts, lighter in weight andeconomical. It converts the rotational motion of thesteering wheel into the linear motion needed to turnthe wheels. It provides a gear reduction, making iteasier to turn the wheels. Re circulating steeringsystem is used in heavy vehicle but for solar car therack and pinion would be the good choice. In thissteering system we can change the steering ratioaccording to our desire like 12:1, 6:1, 10:1 etc.which will really increase the efficiency of oursolar car.

Fig. 13: Rack and pinion steering system

I. Chain drive

Chain drive is a way of transmitting the mechanicalpower from one place to another. It is often used toconvey power to the wheels of a vehicle, particularlybicycles and motorcycles. It is also used in a widevariety of machines besides vehicles. Most often, thepower is conveyed by a roller chain, known as thedrive chain, passing over a sprocket gear, with theteeth of the gear meshing with the holes in the links ofthe chain. The gear is turned, and this pulls the chainputting mechanical force into the system. There aretwo parts in a chain drive system. Roller chain andsprocket, by simply rotating the chain it can be usedto lift or drag objects. Idler wheel are gears that do notput power into the system or transmit it out. An idler-wheel drive is a system used to transmit the rotationof the main shaft of a motor to another rotatingdevice. An idler gear is a gear wheel that is insertedbetween two or more other gear wheels. Chain drivesystem is a simple mechanical system whose primaryduty is to transfer the mechanical energy from motorto rear axle. The most important point to be noted inchain drive system is that the motor gear and the rearaxle gear must be on a same line

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IIJETperpendicular to the rear axle. Any small error willresult in displacement of chain. In this report, it issuggested to use a 2:1 ratio for teeth at the gearsnear the motor and at the rear axle.

Note: There is a chance of flexibility in chaindrive system. If the individual requirement is to gofor faster speeds then the same ratio as mentionedearlier must be followed with more teeth at themotor and less number of teeth at the rear axle. Ifthe individual requirement is for higher torque dueto hilly or sandy roads, the same ratio in reversemust be followed with more teeth at the rear axleand less number of teeth is the motor gear.

IV. ASSEMBLING

As all the important aspects for construction of thesolar vehicle is covered, there is no requirement ofany professional mechanic to supervise you whenconstructing. The only requirement is a well-equipped workshop which has a good welding,electric cutting machine to cut pipes, plates andsolid rods and a drilling machine to drill into metalwith different bits. The point wise assembling willmake it easier for the assembling to be done withina few hours once all the equipment, materials andsimulations are in hand.

i. Get the mechanical simulation done inCAD software and evaluate using CAEsoftware’s according to selection processdone in the above segments withindividual designs and requirements. Thissimulation is useful to maintain themechanical properties of the vehicleaccording to the standards. This also helpsin giving a fancy touch to the design ofthe vehicle

ii. Accumulate the mechanical materialsaccording to the quantities mentioned inthe simulation like the amount of Al-6063-T1, glass fiber, nuts and bolts,members, spanners, screwdrivers, grease,rack and pinion steering, foursuspensions, chain drive system, twodisc brakes, four disc brake caliper,hydraulic brake set, four wheels, brakepedals, acceleration pedal, fourpedestals with ball bearings,comfortable seats etc.

iii. Order for all the electrical equipmentwith above mentioned specifications likeBLDC motor, motor controller, solarpanels, MPPT solar charge controller,Lithium ion batteries, and requiredquality of electric wires in abundance. Itis also advised to get a soldering set, wire

stripper and some high rating legs for theelectric wires, two DC voltmeters tomeasure the voltage at batteries andmotor, two DC ammeters to measure thecurrent flowing through batteries andmotor, three MCBs.

iv. Mark the Al-6063-Ti metal and cut it tomake a chassis according to simulationand also give additional members forseating, motor mounting and steeringmounting.

v. Mark two circular rods of equal length forboth front and rear axles, fix the discbrake for the front axle with nut and bolt,fix two pedestals from both sides of theaxle and fasten it tight without horizontalmovement. Weld two solid circular platesperpendicular to the axle at both ends ofthe axle which fit exactly to the rims ofthe wheels. Mark holes on the plates, drillthem and fasten the wheels to the axle.Weld two small metal parts in the forwarddirection with holes. Repeat the same withno small metal parts with an additionalchain drive gear in exact middle of theaxle.

vi. Attach both the front and rear axles to thechassis with the pedestals with nut andbolt. Also connect the rack and pinionsteering set to the front axle by boltingthe two ends to the small metal parts withholes and fix the base of the steering tothe main body. (If the steering is nottightly fixed, the vehicle cannot changedirection).

vii. Make a cabinet in the rear to hold theelectrical equipment like motorcontroller, solar charge controller andbatteries. Mount the motor in such away that the motor chain drive gearshould be exactly in line with rear axlegear and fix the motor.viii. Chain the motor and the rear axle

tightly and lubricate it with grease.Build the members and form thebody of the vehicle as per theindividual designs and mount thesolar panels on top of the vehicle. Itis advised to use some thermo colsunder the panels to reduce heat andnoise while travelling.

ix. Complete the wiring of all theelectrical equipment with safetymeasures where ever necessary. Donot short any wires. Fix the brakecalipers to both front and rear axlewith the support of members andattach them with pedals at foot. Alsoconnect the accelerator to motor

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IIJETcontroller and connect it with pedal near the driver’s feet.

x. Place the seats and fix them. Firstswitch on the MCBs at batteries andmotor respectively and go for a test run.If the motor is running satisfactorily, fixthe rest of glass fiber according toindividual designs. Now the new “on-the-run charging solar vehicle” is readyand good to go.

V. Discussions

In extension to this model of solar vehicleaccording to this report, there is scope ordevelopments and also discussing somepractical problems. The introduction ofregenerative braking to the existing modelcan be of a significant boost to the solarvehicle. As for every time the brakes areused, it helps in charging the batteries. Thisdecreases the pressure on the solar panels tocharge the batteries and the batteries can becharged quicker than at present. Whenyou're driving along, energy flows from thebatteries to the motors, turning the wheelsand providing you with the kinetic energyyou need to move. When you stop and hitthe brakes, the whole process goes intoreverse: electronic circuits cut the power tothe motors. Now, your kinetic energy andmomentum makes the wheels turn themotors, so the motors work like generatorsand start producing electricity instead ofconsuming it. Power flows back from thesemotor to the batteries, charging them up. Soa proportion of the energy you lose bybraking is returned to the batteries and canbe reused when you start off again. A solartracking system along with the MPPT solarcharge controller can be an effectiveaddition to the present technology. As thesunlight can be in various direction otherthan the way the vehicle is running or theradiation might be falling slant on the panel,the solar tracking device can track thesunlight and position the panelperpendicular to the radiation and getmaximum output. This helps in highercurrent to charge the batteries faster. Acombination of both the above mentionedtechniques would be a great boost to theavailable technology as proposed in thisreport. Some of the problems faced duringthe construction of the vehicle include thewrong decision of using a belt driven systeminstead of chain driven system which is nothaving enough strength to pull the load andit expands due to heat making the belt loose.

The mechanical brakes are not muchefficient in braking. The nut and boltsshould fit exactly without any movementand the holes must be drilled according tothe nuts available. Trial and error onwelding the materials will result in damageto the quality of the vehicle and increasesthe cost of the vehicle.

VI. TROUBLE SHOOTING

In any vehicle, even after many precautions sometroubles might occur. Any difference from normalworking conditions is considered as a defect andshould be addressed accordingly. Some of the mostcommon troubles in the solar vehicle mentioned inthis report are as under: Some of the most commonproblems such as braking, welding, tires, motorcontroller, motor, battery, steering, solar chargecontroller and other common mechanical parts canbe met with ease using. Also some problems mightrequire extensive look into hem and completereplacement is done which is the final step whilethere is no alternative for that.

VII. CONCLUSION

According to the specifications of electrical andmechanical parts mentioned in this report, theconstruction of the “on-the-run charging solarvehicle” is made simple. The aim of the report isreached in part.

REFERENCES

[1] Electric Vehicle Technology Explained by James Larminie, John Lowry.

[2] Feedback control theory by john Doyle, Bruce Francis, Allen tannenbaum.

[3] Development of generalisedphotovoltaic cell model usingMATLAB/Simulink by Huan-LiangTsai, Ci-Siang Tu, and Yi-JieSu,Member, IAENG.

[4] Drives engineering handbook by Rockwell automation.

[5] Feedback control systems by Dr Mustafa M Aziz.[6] Dynamic performance of a pure electric

vehicle experimental analysisby Wang tan-li,chin chang-hong, Gao shi-zhan, li xing-quanand yuying Xiao.

[7] Hardware design considerations for an electric bicycle using BLDC motor by srivatsa raghunath.

[8] Kelly ebike brushless motor controller user’s manual.

[9] Regenerative braking of BLDC motors byDaniel Torres.

[10] Ac machines controlled as dc machines by Hamid a toliyat.

[11] Powering wireless communications from www.batteryuniversity.com.

[12] A status report of possible risksof base metal alloys by LH pierce

Chief Editor : Shri S.K Jagwani Director Biofuels and ... · steady state and transient...

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Transcript of Chief Editor : Shri S.K Jagwani Director Biofuels and ... · steady state and transient...