Torque coordinated control of PHEV based on the fuzzy and sliding mode method with load torque observer

Due to the torque fluctuation in the mode transition caused by the different response speed of motor and engine, a novel torque coordinated control strategy is proposed in this paper. First, a simplified model of parallel hybrid electric vehicle(PHEV) is constructed. Then a coordinated control method based on the sliding mode control is studied. In order to improve the control performance, the fuzzy control is used to adjust the switching gain of the sliding mode control, and an observer is designed to estimate the load torque in order to improve the ability of resisting load disturbance. In the end, the simulation model of vehicle power system is established in Matlab/Simulink, and the simulation results show that the method can reduce the torque ripple effectively, which will contribute to improve the comfort of the vehicle.