永磁同步电机全速域无传感器复合控制与仿真

Permanent Magnet Synchronous Motor Full-Speed-Range Sensorless Composite Control Strategy

摘要: 永磁同步电机无位置传感器控制策略存在控制精度低、速域切换不平稳问题，由此本研究提出一种新的复合策略以实现全速域高性能控制。在零、低速区域采用高频方波注入法，即向电机定子绕组中注入高频方波信号利用电机的凸极效应，通过采样加减分离法分离出高频电流信号和基波电流信号避免了在转子位置提取过程中使用滤波器，提高了转子位置观测的精度。在中、高速区域，基于电机反电动势进行位置估算的传统滑模观测器具有强鲁棒性，但是符号函数增大了系统抖振和电流谐波，为此引入sigmoid函数进行改进。最后通过采用加权平均法高效实现两种控制策略之间的切换。仿真实验结果验证了所提控制策略的可行性和有效性。

Abstract: The position sensorless control strategy for permanent magnet synchronous motors has problems of low control accuracy and unstable speed range switching. Therefore, this study proposes a new composite strategy to achieve high-performance control over the full-speed-range. In the zero and low-speed regions, the high-frequency square wave injection method is adopted, that is, high-frequency square wave signals are injected into the stator windings of the motor to utilize the convex pole effect of the motor. By using the sampling addition and subtraction separation method, the high-frequency current signal and the fundamental current signal are separated, avoiding the use of filters during the rotor position extraction process, thereby improving the accuracy of rotor position observation. In the medium and high-speed regions, the traditional sliding mode observer based on the motor reverse electromotive force for position estimation has strong robustness, but the sign function increases system jitter and current harmonics. To address this, the sigmoid function is introduced for improvement. Finally, the switching between the two control strategies is efficiently achieved using the weighted average method. The simulation results verify the feasibility and effectiveness of the proposed control strategy.