异步电动机直接转矩控制中的死区效应的仿真研究

逆变器是直接转矩控制系统主电路中的关键部件。逆变器死区的设置虽然防止了逆变器器件的直通,同时也带来了死区效应,特别是对直接转矩控制系统的影响更是明显。本文通过分析异步电动机直接转矩控制系统中死区的生成及死区对电动机和整个系统的影响,定义了偏差电压矢量,并在此基础上,提出了一种死区补偿分析算法。该方法不需附加硬件,只需对原控制软件进行修改。仿真结果显示,在直接转矩控制系统中加入死区补偿,能有效改进电动机定子电流波形,使转矩脉动减小,整个系统的运行性能得到了一定的改善。

Study on Simulation of Dead-Time Effect in DTC of Asynchronous Motor

Inverter is the key part in system main circuit of DTC.Setting of dead-time prevents direct connection between inverter components,however,it also comes into bring dead-time effect,especially in DTC,the effect is obvious.The paper analyses the effect of dead-time on motor and DTC system,and proposes the method for dead-time compensation analysis,which is simple and doesn't need any additional hardware.It can be realized by modifying the control software.Simulation results show that the DTC system gets both good dynamic performance and current waves because of compensation of dead-time.