New Generation and Hybrid Vehiles

8/13/2019 New Generation and Hybrid Vehiles

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NEW GENERATION AND HYBRID VEHILESUNIT-1Electric and hyrid !ehicle"# $le%ile $&el !ehicle" '((V)# S*lar +*,ered!ehicle#a.netic trac/ !ehicle"# $&el cell" !ehicle0

ELETRI VEHIELSThe first electric vehicles of the 1830s used non-rechargeable batteries. Half acenturywas to elapse before batteries had developed sufficiently to be used in commercialelectric vehicles. By the end of the 1th century! with mass production ofrechargeablebatteries! electric vehicles became fairly widely used. "rivate cars! though rare! were#uite li$ely to be electric! as were other vehicles such as ta%is. &n electric 'ew (or$ta%ifrom about 101 is shown! with )ily )ang tree alongside! in *igure 1.1. +ndeed ifperformance was re#uired! the electric cars were preferred to their internal

combustionor steam powered rivals. *igure 1., shows the first car to e%ceed the mile a minutespeed /0mph when the Belgium racing diver 2amille enat4y! driving the electricvehicle $nown as )aamais 2ontente!1 set a new land speed record of 10 $ph/5.6mph. This also made it the first car to e%ceed 100 $ph. &t the start of the ,0thcentury electric vehicles must have loo$ed a strong contender for future roadtransport.2amille enat4ys )a amais 2ontente. This electric car held the world landspeed record in 18! and was the first vehicle to e%ceed both 0mph and 100 $ph7hereas internal combustion engine vehicles were at the time unreliable! smelly and'eeded to be manually cran$ed to start. The other main contender! the steamengineehicle! needed lighting and the thermal efficiency of the engines was relatively low.By the 1,0s several hundred thousand electric vehicles had been produced for useas2ars! vans! ta%is! delivery vehicles and buses. However! despite the promise of theearly*or e%ample! the ,.6 tonnes of lead acid batteries which give the same effectiveenergystorage as 95 litres /10 :; gallons of petrol would cost around


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#uiet non-polluting buses to be used in towns and cities. 7hen away from theelectricalsupply.U"e" $*r ,hich attery electric !ehicle" ha!e reained +*+&lar 2>espite the above problems there have always been uses for electric vehicles since

theearly part of the ,0th century. They have certain advantages over combustionengines!mainly that they produce no e%haust emissions in their immediate environment! andsecondly that they are inherently #uiet. This ma$es the electric vehicle ideal for aswarehouses! inside buildings and on golf courses! where pollution and noise will notbetolerated.?ne popular application of battery@electric drives is for mobility devices for the elderlyand physically handicapped. +ndeed! in Aurope and the :nited =tates the type ofvehicle

shown in *igure 1.9 is one of the most common. +t can be driven on pavements! intoshops! and in many buildings. 'ormally a range of 9 miles is #uite sufficient butlongerranges allow disabled people to drive along country lanes. &nother vehicle of thisclassis shown in *igure 11., of the final chapter.They also retain their efficiencies in start-stop driving! when an internal combustionengine becomes very inefficient and polluting. This ma$es electric vehicles attractiveforuse as delivery vehicles such as the famous British mil$ float. +n some countries thishasbeen helped by the fact that leaving an unattended vehicle with the engine running!fore%ample when ta$ing something to the door of a house! is illegal.BATTERY ELETRI VEHILES THE ONE3T O( THE BATTERY ELETRIVEHILE IS ESSENTIALLY SI43LE AND IS SHOWN IN (IGUREThe vehicle consists of an electric battery for energy storage! an electric motor!and a controller. The battery is normally recharged from mains electricity via a pluganda battery charging unit that can either be carried onboard or fitted at the chargingpoint.

The controller will normally control the power supplied to the motor! and hence thevehicle speed! in forward and reverse. This is normally $nown as a , #uadrantcontroller! forwards and bac$wards. +t is usually desirable to use regenerativebra$ingboth to recoup energy and as a convenient form of frictionless bra$ing. 7hen inadditionthe controller allows regenerative bra$ing in forward and reverse directions it is$nownas a 9 #uadrant controller.9There is a range of electric vehicles of this type currently available on the mar$et.&t the simplest there are small electric bicycles and tricycles and small commuter

vehicles. +n the leisure mar$et there are electric golf buggies. There is a range of fullsi4ed electric vehicles! which include electric cars! delivery truc$s and buses. &mong


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the most important are also aids to mobility! as in *igure 1.9 and *igure 11., /in thefinalchapter! and also delivery vehicles and electric bicycles. =ome e%amples of typicalelectrical vehicles using rechargeable batteries are shown in *igures 1. to 1.. &ll ofthese vehicles have a fairly

THE I ENGINE5ELETRI HYBRID VEHILE 2& hybrid vehicle has two or more power sources! and there are a large number ofpossible variations. The most common types of hybrid vehicle combine an internalcombustion engine with a battery and an electric motor and generator.There are two basic arrangements for hybrid vehicles! the series hybrid and theparallelhybrid! which are illustrated in *igures 1. and 1.10 +n the series hybrid the vehicle isdriven by one or more electric motors supplied either from the battery! or from the +2engine driven generator unit! or from both. However! in either case the driving forcecomes entirely from the electric motor or motors.+n the parallel hybrid the vehicle can either be driven by the +2 engine wor$ing

directlythrough a transmission system to the wheels! or by one or more electric motors! orbyboth the electric motor and the +2 engine at once.+n both series and parallel hybrids the battery can be recharged by the engine andgenerator while moving! and so the battery does not need to be anything li$e aslargeas in a pure battery vehicle. &lso! both types allow for regenerative bra$ing! for thedrive motor to wor$ as a generator and simultaneously slow down the vehicle andcharge the battery.The series hybrid tends to be used only in specialist applications. *or e%ample! thediesel powered railway engine is nearly always a series hybrid! as are some ships.=ome special all-terrain vehicles are series hybrid! with a separately controlledelectricmotor in each wheel. The main disadvantage of the series hybrid is that all theelectricalenergy must pass through both the generator and the motors. The adds considerablytothe cost of such systems.The parallel hybrid! on the other hand! has scope for very wide application. Theelectric

machines can be much smaller and cheaper! as they do not have to convert all theenergy.

There are various ways in which a parallel hybrid vehicle can be used. +n thesimplest it can run on electricity from the batteries! for e%ample! in a city wheree%haustemissions are undesirable! or it can be powered solely by the +2 engine! fore%ample!when traveling outside the city. &lternatively! and more usefully! a parallel hybridvehiclecan use the +2 engine and batteries in combination! continually optimi4ing the

efficiencyof the +2 Angine.


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HAs evolved out of two basic configurations series and parallel. & series hybrid isonein which only one energy converter can provide propulsion power. The heat engineor+2A acts as a prime mover in this configuration to drive an electric generator that

delivers power to the battery or energy storage lin$ and the propulsion motor. Thecomponent arrangement of a series HA is shown in *igure 10.1.& parallel hybrid is one in which more than one energy source can providepropulsionpower. The heat engine and the electric motor are configured in parallel! with amechanical coupling that blends the tor#ue coming from the two sources. Thecomponent arrangements of a parallel hybrid are shown in *igure 10.,.=eries HA is the simpler type! where only the electric motor provides all thepropulsionpower. & downsi4ed heat engine on board drives a generator! which supplementsthe batteries and can charge them when they fall below a certain state

of charge. The power re#uired to move the vehicle is provided solely by the electricmotor. Beyond the heat engine and the generator! the propulsion system is the sameasin an A! ma$ing electric motor power re#uirements the same as for in the A.+n parallel HA! the heat engine and the electric motor are connected to thedriveshaftthrough separate clutches. "ower re#uirements of the electric motor in the parallelhybrid are lower than that of an A or series hybrid! because the heat enginecomplements for the total power re#uirement of the vehicle. The propulsion powermaybe supplied by the heat engine! by the battery-motor set! or by the two systems incombination.=eries and parallel hybrids come in a variety of types. The mission of the vehicle andthe optimum design for that mission dictate the choice. +f the HA is to be basicallyanA with an +2A-assist for achieving acceptable range! then the choice should be aseries hybrid! with the +2A ensuring that the batteries remain charged all the time.?nthe other hand! if the HA is to be basically a vehicle with almost all the performancecharacteristics and comforts of an +2A but with lower emission and fuel usagestandards! then the choice should be a parallel configuration. "arallel HAs have

beenbuilt with performance that is e#ual! in all aspects of normal operation! to that of aconventional car. However! some series HAs have also been built that performnearlyas well as +2As.Advantages and DisadvantagesThe advantages and disadvantages of series and parallel hybrids are summari4ed inthe following.1. *le%ibility of location of engine-generator set,. =implicity of drive train3. =uitability for short trips

The disadvantages of a series HA are1. +t needs three propulsion components +2A! generator! and motor.


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,. The motor must be designed for the ma%imum sustained power that the vehiclemayre#uire! such as when climbing a high grade. However! the vehicle operates belowthema%imum power most of the time.

3. &ll three drive train components need to be si4ed for ma%imum power forlongdistance!sustained! high-speed driving. This is re#uired! because the batteries wille%haust fairly #uic$ly! leaving +2A to supply all the power through the generator.The following are advantages of a parallel HA1. +t needs only two propulsion components +2A and motor@generator. +n parallelHA!the motor can be used as the generator and vice versa.,. & smaller engine and a smaller motor can be used to get the same performance!untilbatteries are depleted. *or short-trip missions! both can be rated at half the

ma%imumpower to provide the total power! assuming that the batteries are never depleted. *orlong-distance trips! the engine may be rated for the ma%imum power! while themotor@generator may still be rated to half the ma%imum power or even smaller.The following are disadvantages of a parallel HA1. The control comple%ity increases significantly! because power flow has to beregulated and blended from two parallel sources.,. The power blending from the +2A and the motor necessitates a comple%mechanicaldevice.SERIES-PARALLEL COMBINATION&lthough HAs initially evolved as series or parallel! manufacturers later reali4ed theadvantages of a combination of the series and parallel configurations for practicalroadvehicles. +n these combination hybrids! the heat engine is also used to charge thebattery. The recently available Toyota "rius is an e%ample of such a hybrid! where asmall series element is added to the primarily parallel HA. The small series elementensures that the battery remains charged in prolonged wait periods! such as at trafficlights or in a traffic Cam. These combination hybrids can be categorically classifiedunderparallel hybrids! because they retain the parallel structure of a component

arrangement.+t is important to stress the fact that the detailed configuration of an HA depends onthe application and the trade-off between cost and performance.The component arrangement of a series-parallel combination hybrid is shown in*igure10.3. The schematic is based on the Toyota "rius hybrid design. & power splitdeviceallocates power from the +2A to the front wheels through the driveshaft and theelectricgenerator! depending on the driving condition. The power through the generator isused

to charge the batteries. The electric motor can also deliver power to the front wheelsin


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parallel to the +2A. The inverter is bidirectional and is used to charge the batteriesfromthe generator or to condition the power for the electric motor. *or short burstsofspeed!power is delivered to the driveshaft from the +2A and the electric motor. & central

control unit regulates the power flow for the system using multiple feedbac$ signalsfromthe various sensors. :se of the +2A to charge the batteries should be minimi4edwhenma%imi4ing efficiency. Anergy is always lost while charging and discharging thebatteryand during the power flow through the inverter.The vehicle should be operated off its engine or battery or both! until the battery is ataminimum acceptable state of charge! say ,0 to 90D. The battery should be chargedfrom the power grid when convenient.

A FLEXIBLE-FUEL VEHICLE (FFV OR DUAL-FUEL VEHICLE !"#e$-"%e# ve&i'#e is an alternative fuel vehicle with an internal combustion enginedesigned to run on more than one fuel! usually gasoline blended with either ethanolormethanol fuel! and both fuels are stored in the same common tan$. *le%-fuel enginesare capable of burning any proportion of the resulting blend in the combustionchamberas fuel inCection and spar$ timing are adCusted automatically according to the actualblend detected by electronic sensors. *le%-fuel vehicles are distinguished from bi-fuelvehicles! where two fuels are stored in separate tan$s and the engine runs on onefuelat a time! for e%ample! compressed natural gas /2'E! li#uefied petroleum gas/)"E!or hydrogen.The most common commercially available ** in the world mar$et is the ethanolfle%ible-fuel vehicle! with ,,. million automobiles! motorcycles and light duty truc$ssoldworldwide by ,010! and concentrated in four mar$ets! Bra4il /1,.5 million! the:nited=tates /.3 million! 2anada /more than 00!000! and Aurope! led by =weden

/,1!65. The Bra4ilian fle% fuel fleet includes 515!6, fle%ible-fuel motorcycles soldsince ,00. +n addition to fle%-fuel vehicles running with ethanol! in Aurope and the:=!mainly in 2alifornia! there have been successful test programs with methanol fle%-fuelvehicles! $nown as F85 fle%-fuel vehicles. There have been also successful testsusing"-series fuels with A85 fle% fuel vehicles! but as of une ,008! this fuel is not yetavailable to the general public. These successful tests with "-series fuels wereconducted on *ord Taurus and >odge 2aravan fle%ible-fuel vehicles.Though technology e%ists to allow ethanol **s to run on any mi%ture of gasoline

and


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ethanol! from pure gasoline up to 100D ethanol /A100! 'orth &merican andAuropeanfle%-fuel vehicles are optimi4ed to run on a ma%imum blend of 15D gasoline with85Danhydrous ethanol /called A85 fuel. This limit in the ethanol content is set to reduce

ethanol emissions at low temperatures and to avoid cold starting problems duringcoldweather! at temperatures lower than 11 G2 The alcohol content is reduced during thewinter in regions where temperatures fall below 0 G2 to a winter blend of A60 in the:.=. or to A65 in =weden from 'ovember until Farch. Bra4ilian fle% fuel vehicles areoptimi4ed to run on any mi% of A,0-A,5 gasoline and up to 100D hydrous ethanolfuel/A100. The Bra4ilian fle% vehicles are built-in with a small gasoline reservoir for coldstarting the engine when temperatures drop below 15 G2. &n improved fle% motorgeneration was launched in ,00 which eliminated the need for the secondary gastan$.

Te)in*#*g+&s ethanol **s became commercially available during the late 10s! the commonuse of the term fle%ible-fuel vehicle became synonymous with ethanol **s. +n the:nited =tates fle%-fuel vehicles are also $nown as A85 vehicles. +n Bra4il! the **sare popularly $nown as total fle% or simply fle% cars. +n Aurope! **s are also$nownas fle%ifuel vehicles. &utoma$ers! particularly in Bra4il and the Auropean mar$et!usebadging in their ** models with the some variant of the word fle%! such as olvoFlexifuel! or ol$swagen Total Flex! or 2hevrolet FlexPower or Ienault Hi-Flex! and*ord sells its *ocus model in Aurope as Flexifuel and as Flex in Bra4il. +n the :=!onlysince ,008 ** models feature a yellow gas cap with the label A85@Easolinewrittenon the top of the cap to differentiate A85s from gasoline only models.*le%ible-fuel vehicles /**s are based on dual-fuel systems that supply both fuelsintothe combustion chamber at the same time in various calibrated proportions. Themostcommon fuels used by **s today are unleaded gasoline and ethanol fuel. Athanol**s can run on pure gasoline! pure ethanol /A100 or any combination of both.

Fethanol has also been blended with gasoline in fle%-fuel vehicles $nown as F85**s!but their use has been limited mainly to demonstration proCects and smallgovernmentfleets! particularly in 2alifornia.

Bi-fuel vehicles. The term fle%ible-fuel vehicles is sometimes used to includeother alternative fuel vehicles that can run with compressed natural gas /2'E!li#uefied petroleum gas /)"EJ also $nown as autogas! or hydrogen. However! allthese vehicles actually are bi-fuel and not fle%ible-fuel vehicles! because theyhave engines that store the other fuel in a separate tan$! and the engine runs onone fuel at a time. Bi-fuel vehicles have the capability to switch bac$ and forth

from gasoline to the other fuel! manually or automatically. The most commonavailable fuel in the mar$et for bi-fuel cars is natural gas /2'E! and by ,008


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there were ! million natural gas vehicles! led by "a$istan /,.0 million!&rgentina /1.6 million! and Bra4il /1. million. 'atural gas vehicles are a popularchoice as ta%icabs in the main cities of &rgentina and Bra4il. 'ormally! standardAU2029- NEW GENERATION AND HYBRID VEHICL

ANIL BABU,S D,A,E B,E (AUTO M,E (AUTO

gasoline vehicles are retrofitted in speciali4ed shops! which involve installing thegas cylinder in the trun$ and the 2'E inCection system and electronics. Fultifuel vehicles are capable of operating with more than two fuels. +n ,009 EF

do Brasil introduced the 2hevrolet &stra ,.0 with a Fulti"ower engine built onfle% fuel technology developed by Bosch of Bra4il! and capable of using 2'E!ethanol and gasoline /A,0-A,5 blend as fuel. This automobile was aimed at theta%icab mar$et and the switch among fuels is done manually. +n ,00 *iatintroduced the *iat =iena Tetra fuel! a four-fuel car developed under FagnetiFarelli of *iat Bra4il. This automobile can run as a fle%-fuel on 100D ethanol/A100J or on A-,0 to A,5! Bra4ilKs normal ethanol gasoline blendJ on puregasoline /though no longer available in Bra4il since 13! it is still used in

neighboring countriesJ or Cust on natural gas. The =iena Tetrafuel wasengineered to switch from any gasoline-ethanol blend to 2'E automatically!depending on the power re#uired by road conditions. &nother e%isting option is toretrofit an ethanol fle%ible-fuel vehicle to add a natural gas tan$ and thecorresponding inCection system. This option is popular among ta%icab owners in=Lo "aulo and Iio de aneiro! Bra4il! allowing users to choose among threefuels /A,5! A100 and 2'E according to current mar$et prices at the pump.ehicles with this adaptation are $nown in Bra4il as tri-fuel cars.

*le%-fuel hybrid electric and fle%-fuel plug-in hybrid are two types of hybridvehicles built with a combustion engine capable of running on gasoline! A-85! orA-100 to help drive the wheels in conCunction with the electric engine or to

recharge the battery pac$ that powers the electric engine. +n ,006 *ord produced,0 demonstration Ascape Hybrid A85s for real-world testing in fleets in the :.=.&lso as a demonstration proCect! *ord delivered in ,008 the first fle%ible-fuel pluginhybrid =: to the :.=. >epartment of Anergy />?A! a *ord Ascape "lug-inHybrid! which runs on gasoline or A85. EF announced that the 2hevrolet oltplug-in hybrid! launched in the :.=. in late ,010! would be the first commerciallyavailable fle%-fuel plug-in capable of adapting the propulsion to several worldmar$ets such as the :.=.! Bra4il or =weden! as the combustion engine can beadapted to run on A85! A100 or diesel respectively. The olt is e%pected to befle%-fuel-capable in ,013. )otus Angineering unveiled the )otus 2ity2ar at the,010 "aris Fotor =how. The 2ity2ar is a plug-in hybrid concept car designed forfle%-fuel operation on ethanol! or methanol as well as regular gasoline.Hist*+The first commercial fle%ible fuel vehicle was the *ord Fodel T! produced from 108through 1,6. +t was fitted with a carburetor with adCustable Cetting! allowing use ofgasoline or ethanol! or a combination of both. ?ther car manufactures also providedengines for ethanol fuel use. Henry *ord continued to advocate for ethanol as fuelevenduring the prohibition. However! cheaper oil caused gasoline to prevail! until the163 oilcrisis resulted in gasoline shortages and awareness on the dangers of oil

dependence.This crisis opened a new opportunity for ethanol and other alternative fuels! such as


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to monitor the carKs energy consumption! solar energy capture and other parametersand free the driver to concentrate on driving.&s an alternative! a battery-powered electric vehicle may use a solar array torechargeJthe array may be connected to the general electrical distribution grid.

Sing#e-ta'/ ve&i'#es& solar bicycle or tricycle has the advantage of very low weight and can use theridersfoot power to supplement the power generated by the solar panel roof. +n this way! acomparatively simple and ine%pensive vehicle can be driven without the use of anyfossil fuels.=olar photovoltaics helped power +ndiaKs first Ouadricycle developed since 1 inEuCarat stateKs =:I&T city.The first solar cars were actually tricycles or #uadricycles built with bicycletechnology.These were called solarmobiles at the first solar race! the Tour de =ol in =wit4erland

in185 with 6, participants! half using e%clusively solar power and half solar-humanpoweredhybrids. & few true solar bicycles were built! either with a large solar roof! asmall rear panel! or a trailer with a solar panel. )ater more practical solar bicycleswerebuilt with foldable panels to be set up only during par$ing. Aven later the panels wereleft at home! feeding into the electric mains! and the bicycles charged from themains.Today highly developed electric bicycles are available and these use so little powerthatit costs little to buy the e#uivalent amount of solar electricity. The solar has evolvedfrom actual hardware to an indirect accounting system. The same system also wor$sforelectric motorcycles! which were also first developed for the Tour de =ol. This israpidlybecoming an era of solar production. 7ith todayKs high performance solar cells! afrontand rear " panel on this solar bi$e can give sufficient assistance! where the rangeisnot limited by batteries.

A00#i'ati*ns?ne practical application for solar powered vehicles is possibly golf carts! some ofwhich are used relatively little but spend most of their time par$ed in the sun.A%$i#ia+ 0*1e"hotovoltaic modules are used commercially as au%iliary power units on passengercarsin order to ventilate the car! reducing the temperature of the passenger compartmentwhile it is par$ed in the sun. ehicles such as the ,010 "rius! &ptera ,! &udi &8! andFa4da , have had solar sunroof options for ventilation purposes.The area of photovoltaic modules re#uired to power a car with conventional design istoo large to be carried onboard. & prototype car and trailer has been built =olar Ta%i.

&ccording to the website! it is capable of 100 $m@day using m, of standardcrystalline


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silicon cells. Alectricity is stored using a nic$el@salt battery. & stationary system suchasa rooftop solar panel! however! can be used to charge conventional electric vehicles.+t is also possible to use solar panels to e%tend the range of a hybrid or electric car!as

incorporated in the *is$er ;arma! available as an option on the 2hevy olt! on thehoodand roof of >estiny ,000 modifications of "ontiac *ieros! +taldesign Ouaranta! *ree>rive A =olar Bug! and numerous other electric vehicles! both concept andproduction.+n Fay ,006 a partnership of 2anadian companies led by Hymotion added " cellsto aToyota "rius to e%tend the range. =A claims ,0 miles per day from their combined,157 module mounted on the car roof and an additional 3$7h battery.?n une ,008! the Eerman and *rench "residents announced a plan to offer acedit

of -8g@$m of 2?, emissions for cars fitted with technologies not yet ta$en intoconsideration during the standard measuring cycle of the emissions of a car. Thishasgiven rise to speculation that photovoltaic panels might be widely adopted on autosinthe near future.+t is also technically possible to use photovoltaic technology! /specificallythermophotovoltaic /T" technology to provide motive power for a car. *uel is usedtoheat an emitter. The infrared radiation generated is converted to electricity by a lowband gap " cell /e.g. Ea=b. & protoype T" hybrid car was even built. The i$ing, was the 7orlds first thermophotovoltaic /T" powered automobile! designedandbuilt by the ehicle Iesearch +nstitute /I+ at 7estern 7ashington :niversity.Afficiency would need to be increased and cost decreased to ma$e T" competitivewith fuel cells or internal combustion engines.4AGNETI TRA6 VEHILESMag#ev /derived from magnetic levitation! is a system of transportation thatsuspends!guides and propels vehicles! predominantly trains! using magnetic levitation from avery

large number of magnets for lift and propulsion. This method has the potential to befaster! #uieter and smoother than wheeled mass transit systems. The power neededforlevitation is usually not a particularly large percentage of the overall consumptionJmostof the power used is needed to overcome air drag! as with any other high speedtrain.The highest recorded speed of a Faglev train is 581 $ilometres per hour! achieved inapan in ,003! $ilometres per hour faster than the conventional TE wheel-railspeedrecord.

The first commercial maglev people mover was simply called F&E)A andofficially


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opened in 189 near Birmingham! Angland. +t operated on an elevated 00-metresection of monorail trac$ between Birmingham +nternational &irport and Birmingham+nternational railway station! running at speeds up to 9, $m@hJ the system waseventually closed in 15 due to reliability problems."erhaps the most well $nown implementation of high-speed maglev technology

currently operating commercially is the =hanghai Faglev Train! an +?= /initialoperatingsegment demonstration line of the Eerman-built Transrapid train in =hanghai! 2hinathat transports people 30 $m to the airport in Cust 6 minutes ,0 seconds! achieving atopspeed of 931 $m@h! averaging ,50 $m@h.=everal favorable conditions e%isted when the lin$ was built

The British Iail Iesearch vehicle was 3 tonnes and e%tension to the 8 tonnevehicle was easy.

Alectrical power was easily available. The airport and rail buildings were suitable for terminal platforms. ?nly one crossing over a public road was re#uired and no steep gradients were

involved. )and was owned by the railway or airport. )ocal industries and councils were supportive. =ome government finance was provided and because of sharing wor$! the cost

per organi4ation was not high.Te'&n*#*g+The term maglev refers not only to the vehicles! but to the railway system as well!specifically designed for magnetic levitation and propulsion. &ll operationalimplementations of maglev technology have had minimal overlap with wheeled traintechnology and have not been compatible with conventional rail trac$s. Becausetheycannot share e%isting infrastructure! these maglev systems must be designed ascomplete transportation systems. The &pplied )evitation ="F Faglev system isinteroperablewith steel rail trac$s and would permit maglev vehicles and conventional trainsto operate at the same time on the same right of way. F&' in Eermany alsodesigned amaglev system that wor$ed with conventional rails! but it was never fully developed.There are two particularly notable types of maglev technology

*or electromagnetic suspension /AF=! electromagnets in the train attract it to amagnetically conductive /usually steel trac$. Alectrodynamic suspension /A>= uses electromagnets on both trac$ and trainto push the train away from the rail.&nother e%perimental technology! which was designed! proven mathematically! peerreviewed! and patented! but is yet to be built! is the magnetodynamic suspension/F>=! which uses the attractive magnetic force of a permanent magnet array near asteel trac$ to lift the train and hold it in place. ?ther technologies such as repulsivepermanent magnets and superconducting magnets have seen some research.E#e't*)agneti' s%s0ensi*n+n current electromagnetic suspension /AF= systems! the train levitates above asteel

rail while electromagnets! attached to the train! are oriented toward the rail frombelow.


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The system is typically arranged on a series of 2-shaped arms! with the upperportion ofthe arm attached to the vehicle! and the lower inside edge containing the magnets.Therail is situated between the upper and lower edges.

Fagnetic attraction varies inversely with the cube of distance! so minor changes indistance between the magnets and the rail produce greatly varying forces. Thesechanges in force are dynamically unstable - if there is a slight divergence from theoptimum position! the tendency will be to e%acerbate this! and comple% systems offeedbac$ control are re#uired to maintain a train at a constant distance from thetrac$!/appro%imately 15 millimeters.The maCor advantage to suspended maglev systems is that they wor$ at all speeds!unli$e electro dynamic systems which only wor$ at a minimum speed of about [email protected] eliminates the need for a separate low-speed suspension system! and can

simplifythe trac$ layout as a result. ?n the downside! the dynamic instability of the systemdemands high tolerances of the trac$! which can offset! or eliminate this advantage.)aith waite! highly s$eptical of the concept! was concerned that in order to ma$e atrac$with the re#uired tolerances! the gap between the magnets and rail would have to beincreased to the point where the magnets would be unreasonably large. +n practice!thisproblem was addressed through increased performance of the feedbac$ systems!whichallow the system to run with close tolerances.E#e't* d+na)i' s%s0ensi*nI-Faglev A>= suspension is due to the magnetic fields induced either side of thevehicle by the passage of the vehicles superconducting magnets.A>= Faglev "ropulsion via propulsion coils+n electro dynamic suspension /A>=! both the rail and the train e%ert a magneticfield!and the train is levitated by the repulsive force between these magnetic fields. Themagnetic field in the train is produced by either superconducting magnets /as inIFaglevor by an array of permanent magnets /as in +nductrac$. The repulsive force in

the trac$ is created by an induced magnetic field in wires or other conducting stripsinthe trac$. & maCor advantage of the repulsive maglev systems is that they arenaturallystablePminor narrowing in distance between the trac$ and the magnets createsstrongforces to repel the magnets bac$ to their original position! while a slight increase indistance greatly reduces the force and again returns the vehicle to the rightseparation.'o feedbac$ control is needed.Iepulsive systems have a maCor downside as well. &t slow speeds! the current

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in these coils and the resultant magnetic flu% is not large enough to support theweightof the train. *or this reason the train must have wheels or some other form of landinggear to support the train until it reaches a speed that can sustain levitation. =ince atrain

may stop at any location! due to e#uipment problems for instance! the entire trac$mustbe able to support both low-speed and high-speed operation. &nother downside isthatthe repulsive system naturally creates a field in the trac$ in front and to the rear ofthelift magnets! which act against the magnets and create a form of drag. This isgenerallyonly a concern at low speeds! at higher speeds the effect does not have time to buildtoits full potential and other forms of drag dominate.

The drag force can be used to the electrodynamic systemKs advantage! however! asitcreates a varying force in the rails that can be used as a reactionary system to drivethetrain! without the need for a separate reaction plate! as in most linear motor systems.)aithwaite led development of such traverse-flu% systems at his +mperial 2ollegelaboratory. &lternatively! propulsion coils on the guideway are used to e%ert a forceonthe magnets in the train and ma$e the train move forward. The propulsion coils thate%ert a force on the train are effectively a linear motor an alternating current flowing

through the coils generates a continuously varying magnetic field that moves forwardalong the trac$. The fre#uency of the alternating current is synchroni4ed to match thespeed of the train. The offset between the field e%erted by magnets on the train andtheapplied field creates a force moving the train forward.P*s and '*ns *" di""eent te'&n*#*giesAach implementation of the magnetic levitation principle for train-type travel involvesadvantages and disadvantages.Techn*l*.y 3r*" *n"EMS/AlectromagneticsuspensionFagnetic fields inside andoutside the vehicle are less thanA>=J proven! commerciallyavailable technology that canattain very high speeds/500 $m@hJ no wheels orsecondary propulsion systemneeded.The separation between the

vehicle and the guideway mustbe constantly monitored and


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corrected by computer systemsto avoid collision due to theunstable nature ofelectromagnetic attractionJ dueto the systemKs inherent

instability and the re#uiredconstant corrections by outsidesystems! vibration issues mayoccur.EDS/Alectrodynamicsuspension?nboard magnets and largemargin between rail and trainenable highest recorded trainspeeds /581 $m@h and heavy

load capacityJ has demonstrated/>ecember ,005 successfuloperations using hightemperaturesuperconductors inits onboard magnets! cooled withine%pensive li#uid nitrogen.=trong magnetic fields onboardthe train would ma$e the traininaccessible to passengers withpacema$ers or magnetic datastorage media such as harddrives and credit cards!necessitating the use ofmagnetic shieldingJ limitationson guideway inductivity limit thema%imum speed of the vehicleJvehicle must be wheeled fortravel at low speeds.Ind%'ta'/S+ste)/"ermanentFagnet A>=

*ailsafe =uspensionPno powerre#uired to activate magnetsJFagnetic field is locali4ed belowIe#uires either wheels or trac$segments that move for whenthe vehicle is stopped. 'ewAU2029- NEW GENERATION AND HYBRID VEHICL

ANIL BABU,S D,A,E B,E (AUTO M,E (AUTO

the carJ can generate enoughforce at low speeds /around5 $m@h to levitate maglev trainJ

in case of power failure cars slowdown on their own safelyJ


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Halbach arrays of permanentmagnets may prove more costeffectivethan electromagnets.technology that is still underdevelopment /as of ,008 and

as yet has no commercialversion or full scale systemprototype.'either +nductrac$ nor the =uperconducting A>= are able to levitate vehicles at astandstill! although +nductrac$ provides levitation down to a much lower speedJwheelsare re#uired for these systems. AF= systems are wheel-less.The Eerman Transrapid! apanese H==T /)inimo! and ;orean Iotem AF=maglevslevitate at a standstill! with electricity e%tracted from guideway using power rails forthe

latter two! and wirelessly for Transrapid. +f guideway power is lost on the move! theTransrapid is still able to generate levitation down to 10 $m@h speed! using the powerfrom onboard batteries. This is not the case with the H==T and Iotem systems.P*0%#si*n&n A>= system can provide both levitation and propulsion using an onboard linearmotor. AF= systems can only levitate the train using the magnets onboard! notpropel itforward. &s such! vehicles need some other technology for propulsion. & linearmotor/propulsion coils mounted in the trac$ is one solution. ?ver long distances wherethecost of propulsion coils could be prohibitive! a propeller or Cet engine could be used.Sta2i#it+AarnshawKs theorem shows that any combination of static magnets cannot be in astable e#uilibrium. However! the various levitation systems achieve stable levitationbyviolating the assumptions of AarnshawKs theorem. AarnshawKs theorem assumes thatthe magnets are static and unchanging in field strength and that the relativepermeability is constant and greater than unity everywhere. AF= systems rely onactiveelectronic stabili4ation. =uch systems constantly measure the bearing distance and

adCust the electromagnet current accordingly. &ll A>= systems are moving systems/noA>= system can levitate the train unless it is in motion.Because Faglev vehicles essentially fly! stabilisation of pitch! roll and yaw isre#uired bymagnetic technology. +n addition to rotation! surge /forward and bac$ward motions!sway /sideways motion or heave /up and down motions can be problematic withsometechnologies.+f superconducting magnets are used on a train above a trac$ made out of apermanent

magnet! then the train would be loc$ed in to its lateral position on the trac$. +t canmove


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linearly along the trac$! but not off the trac$. This is due to the Feissner Affect.3%idan'e=ome systems use 'ull 2urrent systems /also sometimes called 'ull *lu% systemsJthese use a coil which is wound so that it enters two opposing! alternating fields! sothat

the average flu% in the loop is 4ero. 7hen the vehicle is in the straight aheadposition!no current flows! but if it moves off-line this creates a changing flu% that generates afield that pushes it bac$ into line. However! some systems use coils that try to remainasmuch as possible in the null flu% point between repulsive magnets! as this reduceseddycurrent losses.Eva'%ated t%2es=ome systems /notably the swissmetro system propose the use of vactrainsPmaglev

train technology used in evacuated /airless tubes! which removes air drag. This hasthepotential to increase speed and efficiency greatly! as most of the energy forconventional Faglev trains is lost in air drag.?ne potential ris$ for passengers of trains operating in evacuated tubes is that theycould be e%posed to the ris$ of cabin depressuri4ation unless tunnel safetymonitoringsystems can repressuri4e the tube in the event of a train malfunction or accident.TheIand 2orporation has designed a vacuum tube train that could! in theory! cross the&tlantic or the :=& in ,0 minutes.P*1e and eneg+ %sageAnergy for maglev trains is used to accelerate the train! and may be regained whenthetrain slows down /regenerative bra$ing. +t is also used to ma$e the train levitateandto stabilise the movement of the train. The main part of the energy is needed to forcethe train through the air /air drag. &lso some energy is used for air conditioning!heating! lighting and other miscellaneous systems.The maglev trains are powered onelectromagnetism.&t very low speeds the percentage of power /energy per time used for levitation can

besignificant. &lso for very short distances the energy used for acceleration might beconsiderable. But the power used to overcome air drag increases with the cube ofthevelocity! and hence dominates at high speed /note the energy needed per mileincreases by the s#uare of the velocity and the time decreases linearly..Advantages and disadvantagesC*)0aed t* '*nventi*na# tainsFaCor comparative differences e%ist between the two technologies. *irst of all!maglevsare not trains! they are non-contact electronic transport systems! not mechanical

friction-reliant rail systems. Their differences lie in maintenance re#uirements andthe


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reliability of electronic versus mechanically based systems! all-weather operations!bac$ward-compatibility! rolling resistance! weight! noise! design constraints! andcontrolsystems.

Maintenan'e Re4%ie)ents O" E#e't*ni' Ves%s Me'&ani'a# S+ste)sFaglev trains currently in operation have demonstrated the need for nearlyinsignificant guideway maintenance. Their electronic vehicle maintenance isminimal and more closely aligned with aircraft maintenance schedules based onhours of operation! rather than on speed or distance traveled. Traditional rail issubCect to the wear and tear of miles of friction on mechanical systems andincreases e%ponentially with speed! unli$e maglev systems. This basic differenceis the huge cost difference between the two modes and also directly affectssystem reliability! availability and sustainability.

A##-.eat&e O0eati*ns Faglev trains currently in operation are not stopped!slowed! or have their schedules affected by snow! ice! severe cold! rain or highwinds. This cannot be said for traditional friction-based rail systems. &lso! maglev

vehicles accelerate and decelerate faster than mechanical systems regardless ofthe slic$ness of the guideway or the slope of the grade because they are noncontactsystems.

Ba'/1ads C*)0ati2i#it+ Faglev trains currently in operation are notcompatible with conventional trac$! and therefore re#uire all new infrastructurefor their entire route! but this is not a negative if high levels of reliability and lowoperational costs are the goal. By contrast conventional high speed trains suchas the TE are able to run at reduced speeds on e%isting rail infrastructure! thusreducing e%penditure where new infrastructure would be particularly e%pensive/such as the final approaches to city terminals! or on e%tensions where trafficdoes not Custify new infrastructure. However! this shared trac$ approachignores mechanical railKs high maintenance re#uirements! costs and disruptionsto travel from periodic maintenance on these e%isting lines. The use of acompletely separate maglev infrastructure more than pays for itself withdramatically higher levels of all-weather operational reliability and almostinsignificant maintenance costs. =o! maglev advocates would argue against railbac$ward compatibility and its concomitant high maintenance needs and costs.

E""i'ien'+ >ue to the lac$ of physical contact between the trac$ and the vehicle!maglev trains e%perience no rolling resistance! leaving only air resistance andelectromagnetic drag! potentially improving power efficiency.

.eig&t The weight of the electromagnets in many AF= and A>= designsseems li$e a maCor design issue to the uninitiated. & strong magnetic field isre#uired to levitate a maglev vehicle. *or the Transrapid! this is about 5 wattsper ton. &nother path for levitation is the use of superconductor magnets toreduce the energy consumption of the electromagnets! and the cost ofmaintaining the field. However! a 50-ton Transrapid maglev vehicle can lift anadditional ,0 tons! for a total of 60 tones! which surprisingly does not consumean e%orbitant amount of energy. Fost energy use for the TI+ is for propulsionand overcoming the friction of air resistance. &t speeds over 100 mph! which isthe point of a high-speed maglev! maglevs use less energy than traditional fasttrains.

N*ise Because the maCor source of noise of a maglev train comes fromdisplaced air! maglev trains produce less noise than a conventional train ate#uivalent speeds. However! the psychoacoustic profile of the maglev may


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reduce this benefit a study concluded that maglev noise should be rated li$eroad traffic while conventional trains have a 5-10 dB bonus as they are foundless annoying at the same loudness level.

Design C*)0ais*ns Bra$ing and overhead wire wear have caused problemsfor the *astech 30 railed =hin$ansen. Faglev would eliminate these issues.

Fagnet reliability at higher temperatures is a countervailing comparativedisadvantage /see suspension types! but new alloys and manufacturingtechni#ues have resulted in magnets that maintain their levitational force athigher temperatures.&s with many technologies! advances in linear motor design have addressed thelimitations noted in early maglev systems. &s linear motors must fit within or straddletheir trac$ over the full length of the train! trac$ design for some A>= and AF=maglevsystems is challenging for anything other than point-to-point services. 2urves mustbegentle! while switches are very long and need care to avoid brea$s in current. &n

="Fmaglev system! in which the vehicle is permanently levitated over the trac$s! caninstantaneously switch trac$s using electronic controls! with no moving parts in thetrac$. & prototype ="F maglev train has also navigated curves with radius e#ual tothelength of the train itself! which indciates that a full-scale train should be able tonavigatecurves with the same or narrower radius as a conventional train.

C*nt*# S+ste)s AF= Faglev needs very fast-responding control systems tomaintain a stable height above the trac$J multiple redundancy is built into thesesystems in the event of component failure and the Transrapid system has stilllevitated and operated with fully 1@, of its magnet control systems shut down.?ther maglev systems not using AF= active control are still in the e%perimentalstage! e%cept for the 2entral apan IailwayKs F)Q-01 superconducting A>=repulsive maglev system that levitates 11 centimeters above its guideway.guinea pigsC*)0aed t* ai'a"t*or many systems! it is possible to define a lift-to-drag ratio. *or maglev systemstheseratios can e%ceed that of aircraft /for e%ample +nductrac$ can approach ,001 at highspeed! far higher than any aircraft. This can ma$e maglev more efficient per

$ilometre.However! at high cruising speeds! aerodynamic drag is much larger than lift-induceddrag. et transport aircraft ta$e advantage of low air density at high altitudes tosignificantly reduce drag during cruise! hence despite their lift-to-drag ratiodisadvantage! they can travel more efficiently at high speeds than maglev trains thatoperate at sea level /this has been proposed to be fi%ed by the vactrain concept.&ircraft are also more fle%ible and can service more destinations with provision ofsuitable airport facilities.:nli$e airplanes! maglev trains are powered by electricity and thus need not carryfuel.&ircraft fuel is a significant danger during ta$eoff and landing accidents. &lso! electric

trains emit little direct carbon dio%ide emissions! especially when powered by nuclearor


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&s of ,00! motor vehicles used most of the petroleum used in the :.=. andproducedover 0D of the carbon mono%ide emissions and about ,0D of greenhouse gasemissions in the :nited =tates. +n contrast! a vehicle fueled with pure hydrogenemits

few pollutants! producing mainly water and heat! although the production of thehydrogen would create pollutants unless the hydrogen used in the fuel cell wereproduced using only renewable energy.

New Generation and Hybrid Vehiles

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