Structure design for power-split hybrid transmission

The HEV plays the key role in the energy saving and carbon emission reduction. Typically an HEV combines two power components, an internal combustion engine and an electrical motor. And the large capacity lithium or the Ni-MH battery is also needed. The power-split power train configuration of an HEV has the individual advantages of the series and parallel types of HEV power train configurations. And the planetary gear set (PGS) plays the key role in it. This paper presents a particular power-split power train configuration. The state of the device can switch in the six modes, according to the driving requirement. This improves the over-all efficiency of the power train. As the mode switching strategy has great effect on the vehicle dynamic performance, the interrelationship between SOC and velocity on the mode switching strategy is researched.