Research on the oscillation reduction control during uphill start condition in hybrid electric vehicles

Due to the direct connection of the motor in the hybrid power system to the planetary gear train, the damping elements in the transmission system are insufficient. The changes in motor torque, as well as the clearance and friction of the planetary gear train, make the transmission system prone to torsional vibration when the pure electric vehicle of the hybrid power system is driving at low speed, which affects the overall driving smoothness of the vehicle. To improve the driving and riding quality, an active damping anti-shake control strategy is proposed in this paper. Firstly, a PD feedback corrector was designed based on the simplified model to reconfigure the coefficients of the P and D terms of the system and optimize the natural vibration frequency of the system. Then. The above-mentioned anti-shake strategies were verified through experiments. The vehicle test results show that the active damping strategy can effectively suppress the rotational speed fluctuation of the system in the pure electric condition. The improvement rates for motor speed oscillation and acceleration speed oscillation are 46.4% and 31%, respectively, reducing the impact degree of the entire vehicle, and improve the driving smoothness.