Hybrid engines vary greatly between manufacturers even thought the theory is pretty much the same. Take an efficient petroleum based engine and couple it with a high output electric motor. Additionally design an operating system that can choose the most efficient power source to use depending on the vehicles situation. A gasoline engine
is more efficient at higher engine speeds, while the electric engine is more usable at low rpm. To determine which engine is to be used an integrated computer system is used to control all aspects of the power switch. In most cases the electric motor will start the car in motion, and then when it gets to cruising speed the combustion engine propels the vehicle. If the vehicle is designed with regenerative brakes it means when the brake are applied a progressive variable generator system is engaged. In some hybrids this generator effect is created by changing the electric motor current flow to produce electric power instead of consuming it. By controlling this generating action a user can vary the resistance via the brake pedal
creating more or less resistance.
The hybrid electric motor can vary depending on design. The ford Hybrid engine above is integrated into the transmission and is wide and stout. While the Honda hybrid engine (below) is thin and has a larger circumference and is located between the engine and transmission.
Hybrid transmission can vary also, the transmissions below works by centrifugal force, the faster the wheels spin the higher the gear ratio. Hybrid cars also have conventional 4 or 5 speed style of transmissions. The torque converter has been replaced by an electrically controlled coupler that can be engaged and disengaged. The electric motor has engine has three modes:
* Power Mode - This mode is used to propel the car forward. The motor timing is controlled to produce the most power for a particular application such as an aggressive take off versus a moderate acceleration mode.
* Free-Wheel Mode - This motor mode is used while the car is utilizing the internal combustion engine.
* Braking Mode - This mode is used while the brakes are applied. The car is slowed by causing the electric motor to produce electrical power.