Hybrid Electric Vehicles

By: Henry Phung CalPoly Pomona, Mechanical Engineer

Comparison

http://www.hybridcenter.org/hybrid-center-how-hybrid-cars-work-under-the-hood-2.html

Parallel Hybrid• Both IC Engine and

Electric engine is attached to the drivetrain

• Computers and transmissions allow the two to work in sync

• Smaller batteries• Low power situations

allowed IC to recharge batteries

• IC Engine RPMs vary• More efficient at cruising

Series Hybrid

• Movement only by electric motor

• IC engine charges batteries and provides power for electric motor

• IC Engine is allowed to operated at optimum RPM

• Smaller IC engine, larger batteries/electric motor

Series Continued

• When large amounts of power is needed the electric motor will draw energy from both the IC engine and the batteries

• More efficient with stop and go• Separate motors can be used for each drive wheel

to eliminate chains and differentials• Heavier but will perform as a LSD

Series/Parallel Combined

• Combined is better than either one separate

• Stop and go the car can act as a series

• Cruising the car can act as a parallel

Regenerative Braking

• While braking the batteries or capacitors can be charged

• Electric motor is reversed turning it into a generator