TECHNICAL SEMINARON

HYBRID ELECTRIC VEHICLES

PRESENTED BY:Sanjib ku.DeyAdm no:27I&E/2K

HEVs combine the internal combustion engine of a

conventional vehicle with the

battery and electric motor of

an electric vehicle.

Hybrid power systems were

conceived as a way to compensate for

the shortfall in battery technology. Because batteries could supply only enough energy for

short trips, an onboard generator,

powered by an internal

combustion engine, could be installed

and used for longer trips.

High fuel efficiency.

Decreased emissions.

No need of fossil fuels.

Less overall vehicle weight.

Regenerative braking can be used.

Toyota Prius Honda

Insight Honda

Civic(hybrid)

1.. INTERNAL COMBUSTION ENGINE

2..WHEEL

3.. ELECTRIC MOTOR

4..INTELLIGENT POWER ELECTRONICS

5.. BRAKE

6.. BATTERIES

ThermalManagement

systemHybridPower

unit Tractionmotor

EnergyStorage

unit

Accessories

Fuel tank Body chassisEnergy management

& system control

HEVs will contain a mix of aluminum,

steel, plastic, magnesium, and

composites (typically a strong,

lightweight material composed of fibers in a binding matrix, such as fiberglass).

Ultra capacitors are higher

specific energy and power versions of electrolytic capacitors

devices that store energy as an electrostatic

charge.

Lead acid batteries, used currently in

many electric vehicles, are

potentially usable in hybrid applications. Lead acid batteries can be designed to be high power and are inexpensive,

safe, and reliable.

Flywheels store kinetic energy within a rapidly

spinning wheel-like rotor or disk. Ultimately, flywheels

could store amounts of energy comparable to

batteries. They contain no acids or other potentially

hazardous materials. Flywheels are not affected by temperature extremes,

as most batteries are.

Fuel cells offer highly efficient and fuel-flexible power systems with low

to zero emissions for future HEV designs. There are a variety of thermal

issues to be addressed in the development and

application of fuel cells for hybrid vehicles.

Spark ignition engine mixes fuel and air in a pre-

chamber. Throttle and heat losses,

which occur as the fuel mixture

travels from pre-chamber into the

combustion chamber.

A Compression Ignition engine achieves combustion

through compression without use of sparkplug. It becomes CIDI engine when it is enhanced with direct

injection.

Motors are the "work horses" of HEV drive systems. In an HEV, an electric traction motor converts

electrical energy from the energy storage unit to mechanical energy

that 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. This

characteristic gives the vehicle excellent "off the line" acceleration.

As emissions standards tighten

and exhaust control technologies

improve, the issue of evaporative

emissions becomes increasingly

important. Thermal management of fuel

tanks is one approach to reducing

these emissions.

60% to 80% of amiss ions in an autos

typical driving cycle comes from cold start

emissions, that is, pollutants that are emitted before the

catalytic converter is hot enough to begin

catalyzing combustion products.

Heat recovered from any of the above

sources can be used in a variety of ways. For winter driving, heat recovery from HEV sources such as the power unit exhaust, propulsion motors,

batteries, and power inverter can

significantly improve cabin warm-up.

HEVs are now at the forefront of transportation technology development.

Hybrids have the potential to allow continued growth in the automotive sector,

while also reducing critical resource consumption,

dependence on foreign oil, air pollution, and traffic

congestion.