三电平逆变器异步电动机直接转矩控制系统(II)——合成矢量法

Direct Torque Control of Induction Motor Fed by Three Level Inverter(II)——Method of Synthesizing Vectors

提出了一种基于合成矢量的三电平异步电动机直接转矩控制(DTC)方法,不但有效地控制了三电平逆变器的中点电压,并抑制了输出电压的跳变;而且具有转矩输出高频脉动小,转子转速波动较小的优点。仿真和实验证明此方法在三电平逆变器供电的异步电动机上有效的实现了DTC系统,并能达到优良的控制性能。

A direct torque control strategy (DTC) of induction motor fed by three-level neutral-point-clamped (NPC) inverter has been presented in these author抯 another paper where the problem of neutral point unbalance and high dv/dt has been treated. In this paper, a high performance three-level DTC system is presented based on the concept of fixed synthesizing vectors which can completely resolve the problems of voltage unbalance of neutral point and high dv/dt of output voltage, typical in multilevel inverter. Also the DTC control algorithm for two level inverter could be implemented successfully without major modifications. Finally, the performance of proposed control strategy of induction motor fed by three-level inverter is proved by simulations and experiments.