基于转矩误差预测和SVPWM的异步电机控制研究

Research on direct torque control of induction machine based on the combination of the torque error prediction and SVPWM

针对传统的异步电机直接转矩控制在低速时存在转矩脉动较大的问题,提出了一种减小转矩脉动的直接转矩控制方法.在传统的异步电机直接转矩控制基础上分析了低速时转矩脉动的原因,提出转矩误差预测控制和SVPWM相结合的方法,预测出下一个周期初始非零电压矢量和零电压矢量作用的时间,减少零电压和非零电压切换的次数,可减小转矩的脉动.仿真结果表明,该方法可使转矩快速地收敛于给定值,系统的转矩平稳、性能良好.

In order to reduce the large torque ripple of induction machine subjected to conventional direct torque control （DTC） at low speeds, a new control strategy of DTC was proposed. On the basis of conventional DTC, the reasons for torque ripple at low speeds were analyzed. The control strategy was introduced for the idea combination of the torque error prediction and SVPWM to reduce the torque ripples. The operational time of the non - zero voltage vector and zero voltage vector in the next control period was determined based on the predicted torque error, and the operational times of zero voltage vector will be reduced. Simulation results show that the torque can quickly converge the setting value through the method. It is stable and dynamic performance is good in the system.