Research on the Anti-Shuffle Control for Hybrid Electric Vehicles in the Pure Electric Mode

In hybrid vehicles, the drive motor is directly connected to the drive train and the inherent drive train damping is low. When subjected to external disturbance, the low damping characteristics of the transmission system may cause torsional vibration, which will continue to oscillate the transmission system and affect the driving performance of the vehicle. In this paper, we propose a harmonic injection wheel control method based on motor speed to suppress oscillations and improve the driving performance of hybrid electric vehicles. The harmonic injection control method based on motor speed is based on Fourier transform to decompose sinusoidal harmonics based on specific order of motor speed. RLS algorithm is used to estimate the amplitude and phase, and PI control is used to calculate the compensation torque for the actual amplitude and target amplitude. Simulation and test results show that the proposed control strategy is effective in suppressing oscillations. With the active damping control of the motor, the peak of motor speed fluctuation decreased by 48% before optimization, and the vehicle impact is suppressed to 44.35% before optimization. In parallel mode, the engine anti-vibration control can reduce the vehicle impact by 32% and increase the torque adjustment time by 61%. The results show that the proposed control system can still effectively suppress transmission system oscillation and improve driving performance.