基于三电平拓扑结构的整流器，采用的是电压外环和电流内环的双PI闭环控制，对于三电平整流器的学习有一定的学习作用。-Based on the three level topology of the rectifier, the use of the outer loop and the current loop of the double PI closed-loop control for the study of three level rectifier has a certain role