1. Seminar Presentation
HYBRID ELECTRIC VEHICLE
SUPRABHAT KUMAR
1140880
E-3

2. What are Hybrid Electric Vehicles ?(5)
 A hybrid electric vehicle has two types of energy storage units electricity and fuel.
 A battery is used to store the energy, and that an electromotor will be used as
traction motor.
 Fuel means that a tank is required, and that an Internal Combustion Engine is used to
generate mechanical power, or that a fuel cell will be used to convert fuel to electrical
energy.
Power
source
1
Power
source
2
Hybrid
vehicle

3. Why hybrid electric vehicles ?
 ICE-- only vehicle is inefficient at idle speed, it consumes fuel without providing propulsion power.
 Conventional vehicle -- only 10%–15% of the energy contained in gasoline is converted to traction.
 ICE -- Perform exceedingly well at constant speeds.
 Electric traction motors-- can provide quick acceleration.
 Therefore, Hybrid Electric Vehicle -- the drive train efficiency can potentially be improved to about 30%–
40%.
Goes
1/44 as far as
electric car
Ethanol
Goes ½ as far
as electric car
Goes 1/3rd
as far as
electric car
Bio
mass
Fuel
cell

4. History(1)
 In 1901 Ferdinand Porsche developed the lohner-Porsche hybrid, the first gasoline-electric hybrid
automobile in the world. The hybrid-electric vehicle did not become widely available .
 In 1997 the TOYOTA company release their first hybrid model Toyota Prius in japan.
 After that in 1999 Honda also release their model Honda Insight.
 Worldwide increase in price of petroleum caused many automakers to release hybrids in the late
2000s.
 Lohner-Porsche Toyota Prius

5. Main parts of HEV: -(7)

6. Gasoline electric hybrid structure
1. Gasoline Engine (Internal Combustion Engine): -
 An internal combustion engine (ICE) is a heat engine where the combustion of a fuel occurs with
an oxidizer (usually air) in a combustion chamber.
 In an internal combustion engine the expansion of the high-temperature and high-pressure gases
produced by combustion applies direct force to some component of the engine.
 The force is applied typically to pistons, turbine blades, rotor or a nozzle. This force moves the
component over a distance, transforming chemical energy into useful mechanical energy.
 The engine on a hybrid is smaller and uses advanced technologies to reduce emissions and
increase efficiency.
2. Fuel tank: -
 The fuel tank in a hybrid is the energy storage device for the ICE.
 Gasoline has a much higher density than batteries do. For example it takes 1000 pounds of
batteries to store as much energy as 1 gallon(7 pounds).

7. 3. Electric Motor
 Motors are the "work horses" of Hybrid Electric Vehicle drive systems. The electric traction motor drives the
wheels of the vehicle.
 Unlike a traditional vehicle, where the engine must "ramp up" before full torque can be provided, an electric
motor provides full torque at low speeds.
 The motor also has low noise and high efficiency.
 Electric traction motors convert electrical energy storage unit to mechanical energy that drives the wheels
of the vehicle.
Required features of traction motors are: -
 High power density
 Wide speed range
 High efficiency
 Regenerative braking capability
 Optimized cost
 Robustness

8. Types of traction motors(2)
1. Brushless DC motor: -
 it is also known as electrically commutated motors that are powered by a DC electric source via an integrated
inverter/switching power supply, which produces an AC electric signal to drive the motor.
 Rotor part of the motor is often permanent magnet synchronous motor but also can be switched to induction
motor.
Advantages of BLDC: -
 High efficiency
 Low maintenance
 Easy of control
 High power density
 High torque
 Reduce noise

9. Disadvantages of BLDC: -
 High cost
 Constant power range
 Problem of demagnetisation
 Limited extended speed
2. Induction motor: -
 It is called asynchronous motor also.
 Rotor can be either wound type or squirrel cage type.
 They are rugged, reliable and economical. These motors are used for smaller loads like fans.
 Induction motors are increasingly being used with variable frequency drives (VFD) in variable speed
service.

10. 
Advantages of Induction motor: -
 Robust construction
 Low maintenance cost
 Light weight
 Easy operation
Disadvantages: -
 They have lower efficiency.
 Speed control of this motor is difficult.
 Poor starting torque.
 At low loads power factor is low.

11. 4.Energy Storage Batteries: -(12)
4.1 lead acid batteries:-
 Spongy lead use as negative terminal
 Lead oxide use as positive terminal
 Diluted sulphuric acid is electrolyte
 They deliver high power to the vehicles.
 Cost efficient
 Very safe to use
 Reliable in use
 But they have very low specific energy
 Life cycle is shorter

12. 4.2 Nickel–Metal Hybrid Batteries: -
 Alkaline solution as the electrolyte
 Nickel hydroxide on the positive electrode
 Negative electrode consists of alloy of vanadium, titanium, nickel, and other metals.
 Great specific energy
 Deliver high power and hence more energy efficient
 Longer life cycle
 Safe in use
 The best operation performance is achieved when discharged
20% to 50% of the rated capacity
 More expensive
 Self discharge capacity is very high
 At high temperature they emit tremendous amount of heat
 Cell efficiency is very low

13. 5.Generator : -
 It converts the mechanical power into electrical power.
 The generator is similar to motor but acts only to produce electric power.

14. Main features and Working.(5)

15.  Hybrid-electric vehicles combines the benefits of gasoline engines and electric motors and can be configured
to obtain different objectives, such as improved fuel economy, increased power, or additional auxiliary power
for electronic devices and power tools.
Some of advanced technologies typically used by hybrids include: -
Regenerative Braking :-
 The electric motor applies resistance to the drivetrain causing the wheels to slow down. In return the energy
from the wheels turns the motor ,which is now function as a generator.
 Now it converts the energy which is normally wasted during braking into electricity, which is stored in a
battery until needed by the electric motor.
 With the electronic throttle closed and the vehicle still moving, all of its kinetic energy can be captured to
both slow the vehicle and recharge its battery.

16.  As the on-board computer signals the battery to stop sending electricity (via the controller relay) and start
receiving it (through a charge controller), the M/G simultaneously stops receiving electricity for powering the
vehicle and starts sending current back to the battery for charging.
 But how does generating electricity slow the vehicle? Friction. The armature of the M/G is slowed by the
force of inducing current in the windings as it passes over the opposing poles ​of the magnets in the stator .
 It is this magnetic friction that slowly saps the vehicle's kinetic energy and helps scrub off speed.
Electric motor drive : -
 The electric motor provides additional power to assist the engine in accelerating, passing, or hill climbing.
 This allows a smaller, more efficient engine to be used.
 In some vehicles, the motor alone provides power for low speed driving conditions where internal
combustion engines are least efficient.

17. Automatic start/shutoff:-
 Automatically shuts off the engine when the vehicle comes to a stop and restarts it when the accelerator id
pressed.
 This prevents wasted energy from idling.

18. Types of hybrid structure(8)
1.Series hybrid: -
 In a series hybrid system, the combustion engine drives an electric generator (usually a three-phase
alternator plus rectifier) instead of directly driving the wheels.
 The electric motor is the only means of providing power to the wheels.
 The generator both charges a battery and powers an electric motor that moves the vehicle.
 When large amounts of power are required, the motor draws electricity from both the batteries and the
generator.

19.  They deliver peak energy during acceleration and take regenerative energy during braking. Therefore, the
ultra caps are kept charged at low speed and almost empty at top speed.
 Deep cycling of the battery is reduced, the stress factor of the battery is lowered.
 Example of SHEV:
Renault Kangoo.

20. Advantages of series hybrid : -
 There is no mechanical link between the combustion engine and the wheels. The engine-generator
group can be located everywhere.
 There are no conventional mechanical transmission elements (gearbox, transmission shafts). Separate
electric wheel motors can be implemented easily.
 The combustion engine can operate in a narrow rpm range (its most efficient range), even as the car
changes speed.
 Series hybrids are relatively the most efficient during stop-and-go city driving.
Weakness of series hybrid :-
 The ICE, the generator and the electric motor are dimensioned to handle the full power of the vehicle.
Therefore, the total weight, cost and size of the powertrain can be excessive.
 The power from the combustion engine has to run through both the generator and electric motor. During
long-distance highway driving, the total efficiency is inferior to a conventional transmission, due to the several
energy conversions.

21. 2. Parallel hybrid : -
 Parallel hybrid systems have both an internal combustion engine (ICE) and an electric motor in
parallel connected to a mechanical transmission.
 It combine a large electrical generator and a motor into one unit, often located between the
combustion engine and the transmission.
 The battery can be recharged during regenerative breaking, and during cruising (when the ICE
power is higher than the required power for propulsion).
 As there is a fixed mechanical link between the wheels and the motor (no clutch), the battery
cannot be charged when the car isn’t moving.
 When the vehicle is using electrical traction power only, or during brake while regenerating
energy, the ICE is not running (it is disconnected by a clutch) or is not powered. `

22.  Battery, inverter, and motor are connected in series and then connected to the transmission.
 ICE engine is directly connected to the transmission.

23. Working of parallel hybrid : -(9)
different operating modes of parallel hybrid

24. Advantages : -
 total efficiency is higher during cruising and long-distance highway driving.
 Large flexibility to switch between electric and ICE power
 Compared to series hybrids, the electromotor can be designed less powerful than the ICE, as it is assisting
traction. Only one electrical motor/generator is required.
Disadvantages: -
 Rather complicated system.
 The ICE doesn’t operate in a narrow or constant RPM range, thus efficiency drops at low rotation speed.
 As the ICE is not decoupled from the wheels, the battery cannot be charged at standstill
Honda Civic is based on parallel hybrid.

25. Advantages of hybrid electric vehicle(11)
 Environment Friendly
 Fuel Efficient
 Reduced Noise
 Better Performance
 Less Power
Weaknesses:-
 Low fuel mileage on highway
 Disposal of Hybrid car battery
 Safety - risk of exposure to high voltage wires in case of crash
 Vehicle can be expensive –high maintenance cost

26. Conclusion(13)
Hybrid cars are definitely more environmentally friendly than internal-
combustion vehicles. Batteries are being engineered to have a long
life. When the hybrid cars become more widespread, battery recycling
will become economically possible. Research into other energy
sources such as fuel cells and renewable fuels make the future look
brighter for hybrid cars. EVs, HEVs, FCHVs, and PHEVs have proven to
be ineffective solution for current energy and environment concerns.
With revolutionary contributions of power electronics and ESSs,
electric drive trains totally or partially replace ICEs in these vehicles.
Advanced ESSs are aimed at satisfying the energy requirements of
hybrid power trains.

27. References:-
1. Wikipedia.org
2. http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=4522734&tag=1
3. http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1210630&tag=1
4. http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6243442&tag=1
5. K. Jonasson, “Analysing Hybrid Drive System Topologies”, 2002
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IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 54, NO. 3, MAY 2005
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8. G. Berdichevsky, K.Kelty, JB Straubel and E.Toomre, “The Tesla Roadster Battery System, Tesla Motors”, 2006
9. M. Olszewski “Evaluation of 2004 Toyota Prius Hybrid Electric Drive”, Oak Ridge
10.National Laboratory, May 2005

28. 11. H. Wetzel, R. Bonert, F.P. Dawson, “Converter Configurations for a Serial Hybrid Drive Assuming only Capacitive Energy
Storage”
12. Electric Vehicle Battery Systems
13. B. Randall, “The Future of Cars is Electric”, Tesla Motors, 2008
14. M. Golub, J. Zhang, ”Electric Cars in Arctic Regions”, University of Alaska Fairbanks, Centre for Research Services, Flint
Hills Resources

29. “ Thank You ”