Influence of DC-link voltage pulsation of transmission systems on mechanical structure vibration and fatigue in high-speed trains

Abstract High-speed train transmission systems operate in a multi-source excitation environment, in which the torque pulsation of the traction motor is an important one. According to the principle of AC/DC/AC transmission, a voltage pulsation in the DC-link causes a torque pulsation in the motor. In this paper, an electromechanical coupling model for the traction drive system of high-speed trains was established, and which was used to analyze the effect of DC voltage pulsations on motor current and torque, and further studied the structural fatigue damage of the drive system under electromechanical coupling vibration. A current compensation algorithm was then used to compensate for the DC voltage pulsations and suppress the motor torque pulsations, thus extending the service life of the structure.