基于滑模观测器的永磁同步电机直接转矩控制研究

A Control Scheme of Permanent Magnet Synchronous Motor Under Direct Torque Control Based on Improved Sliding Mode Observer

研究了改进的滑模观测器,相比于传统的滑模观测器,该观测器能够更加准确地以定子电压和电流为变量,估算出转子的速度与位置;利用李雅普洛夫稳定性理论证明了该滑模观测器的稳定性条件。设计了利用该改进滑模观测器作为速度信号来源的永磁同步电机直接转矩控制系统,利用滑模观测器观测出的速度对电机转速进行闭环控制。实验结果表明,采用改进滑模观测器的永磁同步电机直接转矩控制系统,在省去了位置编码器的条件下,依然可以实现电机转矩动态响应快、调速精度高等特点。

An improved sliding mode observer(SMO) was studied,which can estimate position and speed information of the rotor with more accuracy compared with the traditional SMO.Its stability was proved by Lyapunov stability.A control scheme of permanent magnet synchronous motor (PMSM) under direct torque control (DTC) was designed,using the improved SMO as the feedback of speed information.The results show that the method works well without position encoder.The improved SMO can guarantee DTC scheme's quick response and strong robustness.