“…To achieve the desired active damping effect, designing reasonable damping control methodologies is necessary. Various efficient methodologies have been applied to deal with the torsional vibration control problems of HEV: (1) feedforward and feedback control (Alma et al, 2011; Ito et al, 2007; Karikomi et al, 2006; Kim et al, 2011; Kou and Weslati, 2013; Morandin et al, 2015): Karikomi et al used a feedback controller and a feedforward compensator to decrease the vibration of the vehicle drive train, and their method was successfully applied to Nissan Leaf series of electric vehicles; (2) quadratic optimal control (Hao et al, 2018; Kum et al, 2013; Liu et al, 2017; Zhao et al, 2019): Zhao et al proposed an engine start-up control strategy based on optimal control theory to improve the ride comfort of the mode transition process, and the experiment results indicate the proposed control method is effective; (3) robust control (Chang et al, 2014; Njeh et al, 2011; Zhang et al, 2016): Chang et al proposed a robust control strategy based on fuzzy sliding mode control technique to improve the drivability and NVH of HEV especially during mode changes; and (4) model predictive control (MPC) (Caruntu et al, 2011; Vadamalu and Beidl, 2016; Yoon et al, 2010): Vadamalu et al used the MPC algorithm to study the vibration reduction of hybrid vehicles equipped with three-cylinder engines, established a simplified three-degree-of-freedom (3-DOF) model of the transmission system and built a controller, and applied torque control to the motor to attenuate the torsional vibration fluctuations at the motor shaft.…”