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HYBRID ELECTRIC VEHICLE

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INTRODUCTION A hybrid electric vehicle (HEV) augments an electric

vehicle (EV) with a second source of power referred to as the alternative power unit (APU).

A hybrid can achieve the cruising range and performance advantages of conventional vehicles with the low-noise, low-exhaust emissions, and energy independence benefits of electric vehicles

Accordingly, the hybrid concept, where the alternative power unit is used as a second source of energy, is gaining acceptance and is overcoming some of the problems of pure electric vehicles.

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WHAT IS HYBRID ELECTRIC VEHICLE

Any vehicle that combines 2 or more sources of power is said to be hybrid. For example, a moped (a motorized pedal bike), diesel-electric hybrid locomotives

Relies not only on batteries but also on an internal combustion engine which drives a generator to provide electricity and may also drive a wheel.

Alternative power unit to supply the power required by the vehicle, to recharge the batteries, and to power accessories like the air conditioner and heater.

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HYBRID CAR’S CHARACTERSTICS

Better fuel efficiency, up to %80 theoretically possible

Less CO2 emission and pollution Lower maintenance

2009 Toyota PriusHybrid

 2009 Toyota CorollaConventional

5.3 Lit/100 Km 10.5 Lit/100 Km

About $780/year fuel savingsAssume $1 /1L15000km / yearInvaluable benefit for environment

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HYBRID STRUCTURE

Two types of hybrid vehicle configurations

Parallel Hybrids Series Hybrids

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PARALLEL HYBRID Fuel tank, which supplies gasoline to the

engine. Set of batteries that supplies power to

an electric motor. Both the engine and the electric motor

can turn the transmission at the same time, and the transmission then turns the wheels.

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PARALLEL(CONTD.) When the APU is off, the parallel hybrid runs

like an electric vehicle When the APU is on, the controller divides

energy between the drive train (propulsion) and the batteries (energy storage).

Under acceleration, more power is allocated to the drive train than to the batteries. During periods of idle or low speeds, more power goes to the batteries than the drive train.

The batteries also provide additional power to the drive train when the APU is not producing enough and also to power auxiliary systems such as the air conditioner and heater.

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SERIES HYBRID Similar to an electric vehicle with an on-

board generator The vehicle runs on battery power like a

pure electric vehicle until the batteries reach a predetermined discharged level.

At that point the APU turns on and begins recharging the battery.

The APU operates until the batteries are charged to a predetermined level.

APU never directly powers the vehicle

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SERIES (CONTD.)

The length of time the APU is on depends on the size of the batteries and the APU itself.

Since the APU is not directly connected to the drive train, it can be run at its optimal operating condition; hence, fuel economy is increased and emissions are reduced relative to a pure IC engine vehicle.

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COMPONENTS OF HEV Electric drive motors to provide the power for propulsion converts electric energy to mechanical energy

(motion) to drive the hybrid vehicle. Direct Current Motors, Alternating Current Motors

The two possible configurations of electric drive motors in a hybrid vehicle

single electric motor connected to the wheels through a drive train and multiple electric motors, one located at each wheel.

Auxiliary Power Units Supplies the baseline power required to the vehicle,

recharges the batteries and powers accessories such as the air conditioner and heater.

The APU can consist of a mechanical type engine or a fuel cell.

Spark Ignition Engine, Compression Ignition Engines, Fuel Cells

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COMPONENTS (CONTD.) Generators to convert the mechanical power into

electrical power when used in a series hybrid.

Energy Storage Systems Peak power required in hybrid vehicles

is met by devices like batteries, capacitors or a flywheel.

store energy and readily release it when needed.

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COMPONENTS (CONTD.) Regenerative Braking some of the energy is converted into

electrical energy and stored. rotational energy of the braking

mechanism generates electrical power and stores it in the batteries.

Control Systems contains two main components-command

and power components. command component manages and

processes the driver’s instructions. power component chops power flows to

control the motor’s power intake.

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ADVANTAGES OF HEVs

Use less oil than ICE Emit less CO2 than ICE Fuel efficiency increased Honda Insight- 700 mi/tank Toyota Prius- 500 mi/tank Honda Civic Hybrid- 650 mi/tank

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WHO’S MAKING HYBRIDS NOW?

Honda• Accord• Civic• Insight

Toyota• Prius• Camry• Highlander

Ford• Escape

Mazda• Tribute

Saturn• Vue

Lexus• RX 400h SUV• GS 450h• LS 600h L

Mercury• Mariner SUV

Dodge• Ram – contractor’s edition

General Motors• Silverado and Sierra • Malibu• Tahoe/Yukon

Nissan• Altima• Versa

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In the next 5 years…

Growing demand Greater market Car companies will

respond More variety

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HYBRID CAR ISSUES

Currently more expensive than conventional Heavier than conventional, due to battery pack and electric

motors weight Limited battery life Expensive battery pack if you want to replace it Safety issues, high voltage battery and fuel Reliability, still under study, More complex computer controlled systems May have drivability issues Expensive to repair

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HYBRID MILEAGE TIPS Drive slower - The aerodynamic drag on the car

increases dramatically the faster you drive. For example, the drag force at 70 mph (113 kph) is about double that at 50 mph (81 kph). So, keeping your speed down can increase your mileage significantly.

Maintain a constant speed - Each time you speed up the car you use energy, some of which is wasted when you slow the car down again. By maintaining a constant speed, you will make the most efficient use of your fuel.

Avoid abrupt stops - When you stop your car, the electric motor in the hybrid acts like a generator and take some of the energy out of the car while slowing it down. If you give the electric motor more time to slow the vehicle, it can recover more of the energy. If you stop quickly, the brakes on the car will do most of the work of slowing the car down, and that energy will be wasted

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CONCLUSIONS

Using the concept of Hybridization of cars results in better efficiency and also saves a lot of fuel in today’s fuel deficit world.

A hybrid gives a solution to all the problems to some extent.

If proper research and development is done in this field, hybrid vehicle promises a practical, efficient, low pollution vehicle for the coming era.

One can surely conclude that this concept and the similar ones to follow with even better efficiency & conservation rate are very much on the anvil in today’s energy deficit world.

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THANK YOU

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