Post on 28-Mar-2018
International Journal of Advance Engineering and Research Development
Volume 3, Issue 10, October -2016
@IJAERD-2016, All rights Reserved 116
Scientific Journal of Impact Factor (SJIF): 4.14 e-ISSN (O): 2348-4470 p-ISSN (P): 2348-6406
Single Phase to Three Phase System Using Dual Boost Converter to Drive
Induction Motor Along With Active Power Factor Correction Technique
Yuvraj U. Rathod1, Mrs. M. R. Bachawad2
1M.E student, Electrical engineering department, Government College of engineering, Aurangabad, India. 2Associate Professor, Electrical engineering department, Government College of engineering, Aurangabad, India.
Abstract —This paper offerings a single-phase to three-phase drive system composed of dual boost converter, three
phase PWM inverter plus an Induction motor. It gives comparisons between boost and dual boost converter topology.
The proposed system permits enhancements of power factor and sinusoidal input current at the terminal of single phase
source by using current control mode with speed control of three phase induction motor using v/f method. Such a single
phase to three phase conversion technique has large range of application from rural area to industrial area where three
phase machines work easily on available single phase suppl. Finally a MATLAB simulation based model is developed for single phase to three phase system and simulation results are present
Keywords- Average current control mode, Boost converter, Dual boost converter, Induction motor, Power factor,
Rectifier, THD, SPWM
I. INTRODUCTION
Traditionally, conversion of single phase to three phase system conversion has been done by various ways of
switching processes with the help of power electronics devices. It is somewhat common to have only a single phase
power grid in domestic, commercial, manufacturing, and mainly in urban regions; however the variable speed drives may
entreaty a three phase power grid. Single-phase to three-phase AC to DC to AC conversion usually employs a full bridge
topology, which implicates many power switches, such a converter is represented here as conventional topology. As conversion system includes various stages of conversion processes that defines distortion and generate harmonics on
source line and load in system hence the input power factor become poor [1]. Now development in technologies causes
various power factor improvement techniques are employed to overcome these power quality problems some of which
the boost converter topology has been extensively used in various conversion applications [2]. Such that now a days AC
to DC power supplies with power-factor correction (PFC) techniques is almost entirely implemented with boost
topology, usually boost topology does not provide permissible value of higher power factor. So to overcome this
problem, Dual Boost converter technique can be employed to overcome the performance of input characteristic of current
and used to improve input power factor and reduces distortion in input current waveform. [3]. In this paper, a single-
phase to three-phase drive system composed of single-phase rectifiers along with dual boost converter to give boost
output to three phase inverter to drive three phase induction motor along with speed control by using V/F method is
proposed. The proposed system is perceived to operate where the single-phase utility grid is the unique option available.
As Compared to the conventional topology, the proposed system permits to reduce distortion in input currents and the total harmonic distortion (THD) of the system to increase fault tolerance of the system
II. PROPOSED SYSTEM AND BLOCK DIAGRAM
The block diagram showing schematic arrangement of single phase to three phase converter using dual boost
topology to drive induction motor
Fig. 1 Block diagram of implemented scheme
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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Here, schematic arrangement of proposed technique can be divided into two parts such as source of AC link to
DC link conversion and DC link to AC link conversion. So Part 1 composed of an input supply along with line filter to
reduce input harmonics and to make superior input current waveform, a single-phase uncontrolled diode rectifier is used
here to convert AC link into DC link, to increase output of AC/DC converter dual boost topology is used with an active
power factor correction stage using the principle of current control mode technique to maintain power factor up to unity.
Also Part 2 consisting Sinusoidal PWM inverter to convert DC into AC three phase links along with constant V/F
topology to control speed of three phase induction motor using V/F speed control technique [1], [2], [3]
III. DEVELOPMENT OF PROPOSED SYSTEM
3.1 Boost topology
The part of converter consisting of boost chopper termed as Boos converter. Generally boost topology served
two functions such as 1) it controls the line current to be sinusoidal at unity power factor and 2) boost converter is needed
to efficiently convert DC voltage from lower level to higher level [5]
As to reduce losses and converter output is depend on duty cycle their relations are as follows
)1( D
VV s
o
(1)
T
tD on
(2)
The peak to peak ripple current of inductor L is given as
fLVa
VsVoVsI
)( (3)
The peak to peak ripple voltage of capacitor is given as
VofC
VsVoIoVc
)( (4)
The value of inductance respectively the capacitance C of converter are calculated at the boundary operation condition of
the circuit as fallows
f
DRDL
2
)1( (5)
fR
DC
2 (6)
3.2 Principal of control
A dc-dc converter must provide a regulated output voltage DC link under variable load and input voltage conditions.
The converter component values are also varying with temperature, time and pressure. Hence, the control of the output
voltage should be performed in a closed-loop mode using principles of negative feedback system. The two most common
closed-loop control methods for PWM dc-dc converters, namely, the voltage-mode control and the current-mode [2], [3],
[5]
3.2.1 Voltage Mode Control
In this control mode converter technique output voltage of system is controlled and feedback through a resistive
voltage divider. It is compared in a voltage error amplifier with a precision external reference voltage (Vref). The error
amplifier produces a control voltage that is compared with constant amplitude of saw tooth waveform. The comparator or
the PWM Modulator produces a PWM signal that is fed to controlled switches, which is in the dc-dc converter. The duty
ratio of the PWM signal depends on the value of the control voltage [2], [3], [5]
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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Fig. 2 principal of voltage mode control
3.2.2 Current Mode Control
Main objective of this implemented scheme is intensive on Current Mode Control. In this mode of control as shown
in fig., That Signals in current waveform has benefit over voltage signals. Voltage being gathering of flux, which is then
slow in time as far as control strategy, is concerned, this led to the development of a new expanse in switch mode power
supply scheme using mode of current Control. Hence, the average or peak current is employed in the feedback system of
the switch mode power converters. It has given new possibilities of analysis and at same time introduced complexities in
terms of multiple loops. [2], [3], [5]
Fig. 3 Principal of current mode control
3.3 Single phase rectifier circuit with boost topology
In this implemented scheme, the converter consist of uncontrolled diode rectifier is coupled with boost chopper
which is eighter of boost type or dual boost type converter
3.3.1 Single phase rectifier circuit with boost converter
The main principle that energies the boost converter is the tendency of an inductor to resist changes in current, when
being charged it act as a load and absorbs energy as like a resistor. When being discharged it acts as energy source as like a battery. The voltage is creates during the discharge phase is depend on the rate at which change of current and also not
on the original charging voltage, thus allowing different input and output voltages.
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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Fig. 4 boost converter
Fig. 5 On and Off states of a boost rectifier
The input current i(t) is controlled by changing the conduction state of transistor. As transistor is in switching mode by applying suitable firing pulse sequence, hence the waveform of the source side current can be controlled to
follow a sinusoidal reference which can be observed in the positive half wave. The ON and OFF state of switching
periods of the transistor generates an increase and decrease in the inductor current IL [1], [2], [3]
Fig. 6 THD of system using Boost topology (THD=10.71%)
As, it can be clearly seen from fig. 3.2.2 that the higher order harmonics are significantly lowered in the line
current by using a boost converter [1], [2]
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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Fig. 7 Power Factor of system using Boost topology (P.F=0.989)
In case of boost converter due to its simplified structure it is more capable for the power applications of low to
medium range. However, it has a very slow dynamic response and power factor correction. [3]
3.3.2 Single phase rectifier circuit with dual boost converter
To avoid low dynamic response and power factor correction issue, two converters can be connected in Parallel to
form the parallel PFC scheme i.e. dual boost converter. In case of above proposed system power from the ac source to
load flows through two parallel paths. The main path is a rectifier, in which power is not managed double for PFC,
whereas the other path processes the input power twice for PFC purpose. To achieve both output voltage regulation and
unity power factor, only the difference is, there is need to process dually between the input power and output power.
Hence, high efficiency can be obtained by this technique
Fig. 8 Dual Boost converter
Here, we use a parallel scheme, in that choke (Lb1) and switch (Tb1) are for main PFC while choke (Lb2) and
switch (Tb2) are for active filtering. The filtering circuit aids two purposes i.e. it not only improves the quality of line
current but also reduces the PFC total switching loss. The decrease in switching losses arises due to variable values of
switching frequency and current amplitude for the mode of two switches. The comparable connection of switch mode
converter is a well acknowledged strategy. It involves phase shifting of two or more boost converters operating at the
same witching frequency which is connected in parallel [3]
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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Fig. 9 THD of system using Boost topology (THD=8.91%)
Fig. 10 Power Factor of system using Boost topology (P.F=0.992%)
3.4 Inverter Circuit Topology
Inverter circuit is used for converting the DC quantity into the AC quantity. In proposed technique three phase SPWM
inverter, is used to convert DC output of dual boost converter into three phase AC voltage for the speed control of three
phase induction motor using V/F method. Here an SPWM controller is used to drive the gate of the switches used in the
inverter. By proper switching and control technique, inverter generates required voltage or frequencies. There are single phase and three phase inverters but the three-phase inverters are more regularly used in high power applications. This
inverter consists of three half-bridge units; the switching devices can be IGBTs, BJTs, and GTOs. Fig. 3.3.0 shows the
inverter circuit. The controlling of switches depends on the required frequency and desired power. When upper switch is
turned on the corresponding lower switch should turn off and vice versa.
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Fig. 11 PWM Simulink
In case of 3-ph inverters of six modes of operation gating pulses are delayed by 120 degrees are possible for each
cycle and has interval of 60 degrees. Therefore 3-ph voltages lag behind by phase shift of 120 degrees. The inverter
output is a square waveform when it is not connected to a load and such a square shape waveform can be converted into
sine waveform by using LC low pass filter [4].
3.4.1 SPWM Controlled Technique
In case of PWM mechanism topology, the output voltage is controlled by varying the width of pulses, if there are P-pulse
per half cycle, the maximum pulse width is π/P. It is possible to choose the width of pulses in such way that certain harmonics could be eliminated. There are many methods of obtaining pulse with different widths. The most common one technique is the
sinusoidal pulse-width modulation (SPWM) topology. In this technique, the pulse width are generated by comparing a
triangular voltage Vr of amplitude A, and frequency fr with a carrier half sinusoidal voltage Vc of variable amplitude Ac and
frequency of fs [4]
Fig. 12 SPWM Controlled Technique
Here, above figure shows control strategy the reference wave is compared with the carrier wave so the gate pulse is
generated after the comparator operation. The output of comparator is fed to the Arm 1 of bridge inverter.
Fig. 13 PWM carrier wave comparison
Figure 13 shows the waveform of signal obtain from SPWM achieved by Matlab/Simulink model and respective
gate pulse. The Amplitude modulation index is defined as
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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cr
ma
V
VM
(7)
Where,
Vm - peak amplitude of the reference voltage waveform
Vcr - peak amplitude of the triangular voltage waveform
The output voltage is controlled by changing the modulation index M from 0 to 1.
3.5 Induction Motor drive
Induction motor is an electrical to mechanical conservation device and it is an asynchronous AC machine because
the rotor speed is always less than stator magnetic speed. The construction of IM is rugged. Hence, Induction motors are
the most commonly used due to their reliability, low cost and robustness. However, induction motors do not integrally
have the ability of variable speed operation. Due to this reason, earlier dc motors were applied in most of the electrical
drive system, But the recent developments in speed control methods of the induction motor have led to the place where in
large scale use in almost all electrical drives application. [1], [5]. Out of the several methods of speed control of an
induction such as frequency variation, variable rotor resistance pole changing, variable stator voltage, slip recovery
method, constant V/f control, etc. the closed loop constant V/f control speed techniques most commonly used. In this
method, By applying V/f ratio constant which in turn maintaining the maximum torque remains unchanged by taking the
magnetizing flux constant. Thus, the motor is completely utilized in this method. Hence it is widely used in much application like in elevator, water pumping system and in industry [1], [5]
IV. SIMULATION RESULTS AND DISCUSSION
This paper involves simulation of Single Phase To Three Phase System Using Dual Boost Converter To Drive
Induction Motor Along With Active Power Factor Correction Technique circuits and the analysis of the current and
voltage waveforms.
It starts with simple circuits with a gradual increase in complexity by initialization of new constituents and their
consequent effect on the current and voltage waveforms. In this proposed technique we focused on the moto of
improving the input current waveform i.e. making it sinusoidal by tuning the circuits along with maintaining power factor
unity and then with the help of SPWM circuit converter DC dual boost DC link into three phase AC link to drive
induction motor along with their speed control using V/F method. All the simulation work is done in MATLAB Simulink simulation of proposed conversion system
Fig. 14 system model using MATLAB Simulink
The proposed system shown in figure 14 is designed and simulated with the help of tool i.e. MATLAB. In that it consisting of various stages involving AC- to DC link conversion with the help of uncontrolled rectifier
and then feed it into Dual boost topology where the DC link become boosted from lower voltage to higher level
and is given to then PWM inverter. Here Boosted DC link to AC link is done and it given to induction motor for
speed control using V/F topology
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4.1 simulation Single phase rectifier circuit with dual boost converter
Here, two converters can be connected in Parallel to avoid low dynamic response and power factor correction issue,
hence form the parallel PFC scheme i.e. dual boost converter. Here, power from the source of AC to the load flows
through bi-parallel lanes. The main path is a rectifier, in which power is not handled dually for PFC, whereas the other
path possess the input power dually boosted for PFC purpose, to achieve both output voltage regulation and unity power
factor.
Simulation result showed in figure 15, 16 & 17 consisting of source waveform along with power factor and
output of dual boost converter.
Fig. 15 sinusoidal waveform of input current and voltage
Fig. 16 waveform of power factor
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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Fig. 17 waveform of output of dual boost converter
4.2 Inverter Circuit Topology
Inverter circuit is used for converting the DC quantity into the AC quantity. In this proposed technique three phase
SPWM inverter is used to convert DC output of dual boost converter into three phase AC voltage for the speed control of
three phase induction motor using V/F technique. Simulation result shown in following graph 4.2.3 consisting of output of SPWM and rotor speed of three phase induction motor
Fig. 18 waveform of three phase current of PWM
Fig. 19 waveform of three phase voltage of PWM
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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Fig. 20 waveform of rotor speed of three phase induction motor
4.5 Analysis of power factor and thd along with output of boost topology
Sr. No. Circuit topology Power factor THD Output Voltage
1 Boost Converter 0.989 10.71 324
2 Dual Boost Converter 0.992 8.91 415
Table 1.analysist of P.F, THD & output voltage
4.6 Analysis of speed control of i.m. using v/f topology
Sr. No. Frequency(Hz) Speed (rpm)
1 30 Hz 896.5 rpm
2 40 Hz 1198 rpm
3 50 Hz 1493 rpm
Table 2.analysist of frequency & speed
4.7 APPENDIX
Boost converter specification Inductor=0.230H, Capacitor=1.85 µf
Three phase induction motor
specification
1 H.P, 400V, 50Hz, 4 pole , 1440 rpm
Stator & rotor resistance =2Ω & 1.9 Ω
Stator & rotor inductance = 0.0230H,
Mutual inductance= Moment of
inertia=0.02 kg.m2
Table 3 parameters of system
V. CONCLUSION
In this paper The Power Factor Correction with different converters are simulated with MATLAB Simulink.
Paper shown and discussed on result of Boost converter using Current Mode Control and Dual Boost Converter using
Current Mode Control technique, it is noticed that the Power Factor is better for Dual Boost Converter Circuit. Also it is
noticed that THD is less for Dual Boost Converter.
Here output of dual boost converter fed to SPWM inverter further is utilised to drive Induction motor to speed
control. In constant V/F control topology, with the help of PWM inverter, we can vary the supply voltage as well as
frequency such that the ratio V/F remains constant so that the flux remains same. So we can get different operating zone
for various speeds and torques and also we can get various synchronous speeds with almost same maximum torque. Thus the motor is completely utilized and also we have a good range of speed control
International Journal of Advance Engineering and Research Development (IJAERD) Volume 3, Issue 10, October -2016, e-ISSN: 2348 - 4470, print-ISSN: 2348-6406
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REFERENCES
[1] Pradeep M Patil, Sanjay L Kurkute, “Speed control of three phase induction motor using single phase supply
along with active power factor correction,” ACSE Journal, Volume (6), Issue (3), Oct. , 2006
[2] Sudhakar babu, Dr.G. V. Siva Krishna Rao, “Simulation of Active power factor correction using boost type
converter” IJSETR Journal, volume 3, issue 10, October 2014
[3] P .Vijaya Prasuna, J.V.G. Rama Rao, Ch. M. Lakshmi, “Improvement in Power Factor & THD Using Dual
Boost Converter,” IJERA journal, Vol. 2, Issue4, July-August 2012, pp.2368-2376
[4] Mohammad H Rashid, “power electronics Handbook” (Academic press, 2001).
[5] Bimal K. Bose, “Modern power electronics and AC drives”, ISBN-978-81-203-2749-8