Development of a control algorithm to reduce torque variation for the dual mode HEV during mode change

In this study, the mode change characteristics of the dual mode power split type hybrid electric vehicle were investigated, and a control algorithm was proposed to reduce the torque variation of the drive shaft during the mode change. To analyze the characteristics of the dual mode power split transmission during mode change, dynamic models for the planetary gear, engine, motor-generator, battery and vehicle were established, and a performance simulator for the dual mode power split transmission hybrid electric vehicle was developed. Using the simulator, a transient characteristics during the mode change were investigated and a control method was proposed to reduce the torque variation the motor torque compensation. The magnitude of the motor torque was calculated from the inertia torque during the mode change. It was found that the torque variation can be effectively reduced by the proposed control algorithm.