Abstract: The voltage wave propagation process in the stator winding was analyzed using multi-transmission line theory, and an equivalent circuit for calculating the transient voltage distribution in the stator winding of a variable frequency traction motor was proposed. Calculations using the finite element software ANSYS showed that the voltage to ground and the inter-turn voltage of the first turn of the terminal coil were the largest. Keywords: traction motor; transmission line theory; high frequency effect; voltage distribution [b][align=center]Calculation of Transient Voltage Distribution in Windings of Inverter-Fed Traction Motor TON G Laisheng1, WEN Fengxiang2, WU Guangning1, LIN Tongguang1, ZHAN G Guoqin1 (1. College of Electrical Engineering, Westwest Jiaotong University, Chengdu 610031, China; 2. Chengdu Design & Research Institute for Hydroelectric Projects, Chengdu 610072, China)[/align][/b] Abstract : An equivalent circuit is developed based on transmission line theory taking account on high frequency effects. The parameters of the equivalent circuit are calculated by the finite element analysis ANSYS software. Then, the transient voltage distribution in the windings of inverter-fed traction motor is calculated. by the equivalent circuit. The results show that the maximum voltage across the first turn of the end coil and the turn to ground voltages of turns are not different. Key words: traction motor; transmission line theory; high-frequency effect; voltage distribution 0 Introduction Variable frequency speed control system is widely used due to its own characteristics, but the premature damage of the insulation of variable frequency motor has occurred during the application process [126]. High-speed locomotive traction inverters widely use high-speed switching devices such as IGBTs, and the output voltage is a continuous pulse with a steep rising edge. Its uneven distribution in the stator winding of variable frequency traction motor is one of the main factors causing premature damage to the winding insulation [7211]. However, its specific distribution is still unclear, so it is necessary to study its transient voltage distribution to provide the necessary theoretical basis for the design of variable frequency traction motor to prevent premature damage to the stator insulation of the motor. This paper first analyzes the current propagation process in the winding based on the multi-transmission-line theory. Considering the high-frequency losses of the stator winding, an equivalent circuit is proposed for calculating the transient voltage distribution of the stator winding of a variable frequency traction motor. The distributed parameter values ​​of the equivalent circuit are calculated using the finite element analysis software AN2SYS, and the transient voltage distribution of the winding is then calculated using MATLAB software. [b][align=center]For detailed information, please click to download the calculation of transient voltage distribution of the stator winding of a variable frequency traction motor[/align][/b]