Mode and control strategy of HEV equipped with EVT

The Hybrid Electric Vehicle (HEV) equipped with Electric Variable Transmission (EVT) can provide any power while the engine working in optimal status, for the assistance of motor and the battery. The battery must not be overcharged and discharged too much to keep the life and for nature function. This paper lists every working mode of EVT, and presents the PRI of the control strategy and the steps to decide the working-point for engine and the principle to keep the SOC of the battery. The simulation and validate the strategy and the principle.