A cascade speed control system mainly consists of a wound asynchronous motor, a three-phase rectifier and a three-phase thyristor (?) inverter.
串级调速系统的主要组成部分是线绕式异步电动机，三相桥式整流器和三相可控硅逆变器。
2
Based on practice, the reasons of large and medium-sized high voltage wound rotor three-phase asynchronous motor rotor failure were expounded, and viable approach was designed.