optimisation of fuel cell and supercapacitors in electric.pptx

7/30/2019 OPTIMISATION OF FUEL CELL AND SUPERCAPACITORS IN ELECTRIC.pptx

1/38

OPTIMISATION OF FUEL CELL

AND SUPERCAPACITORS IN

FUEL CELL ELECTRICVEHICLES

Presented by: NITHIN JOHN


2/38

WHY ELECTRIC VEHICLESS(EV)

ARE DEVELOPED?

High cost

Exhaust emissions

Low fuel efficiency

Non renewable

of internal combustionengines(ICES)


3/38

ADVANTAGES OF EV

Low emissions

Reasonable efficiency

Low noise


4/38

BUT WHY EVS ARE NOT

ACCEPTED MUCH???

High cost

Large size of battery

Limited life cycle ofbattery


5/38

By using a combination of ICE+ EV = HEV OR HYBRID ELECTRICVEHICLES

BUT STILL

PROBLEM OF EMISSION

PERSISTS..!!!


6/38

FUEL CELL

Chemical energy stored is

converted to electrical energy without combustion.

Hydrogen is combined with oxygen toform water

Water is bye product so no problemof pollution

Vehicles powered by fuel cell havethe advantage of high efficiency, low

noise, large vehicle range.. etc


7/38


8/38


9/38


10/38

OBSTACLES IN DEVELOPING FCEV

High cost of fuel cell

(according to DOEmass produced fuelcell costs 200$ perUNIT as per 2008

records)


11/38

METHODS OF REDUCING COST OF FUEL CELL

REDUCE PER KW COST OF FUEL CELL

By advanced fuel cell development

REDUCE POWER RATING OF FUEL CELL

Use an energy storage device to

supplement extra power requirement inFCEV vehicle


12/38

SUPER CAPACITOR

super capacitor is an electrochemical device that canprovide high capacitance in a very small volume and weight Have very low charging and discharging time


13/38


14/38

FCEV POWERTRAIN


15/38

AT HIGHPOWER

SUPERCAPACITOR+ FUEL CELL

DC LINKVOLTAGE

Atlow

power

Fuelcell

DC LINKVOLTAGE

SUPER

CAPACITOR


16/38

PROPOSED DESIGN

Cost of AC motor , inverter andtransmission are constant forspecific rating of vehicle

So by proper design cost of fuelcell and capacitor stack has tobe reduced.


17/38


18/38

a)Cost of Fuel-Cell Stack andSuper capacitor Bank

Total cost of the fuel cell and capacitor stack is given

by

Q = C1 Mfc Nfc + C2 Msc Nsc

Q=total cost , M= number of units connected in series

N=Number of units connected in parallel

c = cost of single unit


19/38

Cost on fuel cell andcapacitor unit are assumedindependent of & number

CONSTRAINSON C1 & C2

Dc link voltage has to bemaintained stable during allvehicular conditions

Vdc,m = Vdc,n(1 + )

Mfc = Vdc,m/Vfc,m

Msc = Vdc,m/Vsc,m.

Constrainson Mfc &

Msc


20/38

Initial acceleration

Gradability

Maximum speed

Drive cycle


21/38


22/38

DURING INITIAL ACCELARATION

Both fuel cell and super capacitor have to supply power toFCEV power train

Here for given spec it is assumed to have an initialacceleration of 60mi in 10s

If Nfc is smaller Nsc should be greater and vice versa

The combination must lead to 10% dc link variation

Acceptable combinations are found by trial and error method


23/38


24/38

GRADING

Only fuel cell supplies power

Pg = M g g

P from table 3 is calculated as 20.98 kw

let Vdc,min = Vdc,n(1 )

Vfc,min = Vdc,min / Mfc

Nfc= Pg/ (Mfc. Pfc)

vehicle spec.png
http://localhost/var/www/apps/conversion/tmp/scratch_9/vehicle%20spec.pnghttp://localhost/var/www/apps/conversion/tmp/scratch_9/vehicle%20spec.png


25/38


26/38

MAXIMUM VEHICLE SPEED

Here also fuel cell aloneprovides the power

Here assumed maxspeed is 120 mi/hr

Calculated power =

49.19kw


27/38


28/38

DRIVE CYCLE

At high power requirement both fuel cell and super capacitorprovide power and at low power fuel cell provides power alone andcharges super capacitor.

Fig shows characteristics of FTP 75 DRIVING CYCLE


29/38

ACCEPTABLE COMBINATIONS


30/38

RESULTANT CURVE


31/38

where p1 =0.50056; p2 =6.6939; p3 = 42.742;

p4=18.781; and p5 = 115.66. Points B and C are given by

Point B : Nsc =1.43 Nfc =89.2

Point C : Nsc =2.43 Nfc =42.


32/38


33/38


34/38


35/38

The design is implemented for a sample vehicleand the defined vehicle performance.

The cost, volume, and weight of the optimizedfuel-cell stack and super capacitor bank and the

fuel economy of the vehicle are presented.

Simulation results verify that the designedfuel-cell stack and super capacitor bank canprovide all the required vehicle performance.

The limitation of the method is that the designmethod is only applicable to FCEVs powered by a

fuel cell and super capacitor.


36/38

IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 55, NO. 6,NOVEMBER 2006

M. C. Pera, D. Hissel, and J. M. Kauffmann, Fuel cell systems for electricalvehicles, in Proc. IEEE VTC, May 2002, vol. 4, pp. 20972102

web.iitd.ac.in/~sbasu/seminar/presentation/5Dr.G.SASI.KUMAR.pdf

V. Wouk, Hybrids: Then and now, IEEE Spectr., vol. 32, no. 7, pp. 16

21, Jul. 1995.

The Fuel Cell Handbook, U.S. Dept. Energy, Morgantown, WV, 2002.
http://www.maxwell.com/http://www.maxwell.com/


37/38


38/38

optimisation of fuel cell and supercapacitors in electric.pptx

Documents