永磁同步电机全速域无位置传感器复合控制

Position Sensorless Hybrid Control of Permanent Magnet Synchronous Motor in Full Speed Range

针对传统滑模观测器在低速段估算误差大以及脉振高频电压信号注入法造成定子电流谐波含量增大的问题,提出一种适合电机全速域运行的复合控制策略。在零、低速阶段,采用估算精度较高的脉振高频电压信号注入法;在中高速阶段,虽然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,为此通过引入饱和函数对其进行改进。同时,采用加权平均函数实现两种控制策略的平滑切换。研究结果表明,该复合控制策略在低速段弥补了滑模观测器难以提取反电动势的天然缺陷,在中高速段定子电流的总谐波失真得到有效抑制,且在全速范围都具有较好的动态响应性能和估算精度。

Aiming at the problems of large estimation error of traditional sliding mode observer in the low speed segment and the increase of the harmonic content of stator current caused by the pulse vibration high-frequency voltage signal injection method,a composite control strategy suitable for full-speed domain operation is proposed.In the zero and low speed stages,the high-frequency voltage injection method with high estimation accuracy is adopted;in the medium and high speed stages,although the traditional sliding mode observer based on the position estimation of the motor back EMF has strong robustness,the symbolic function increases the system jitter vibration and current harmonics,which is improved by introducing a saturation function.At the same time,the weighted average function is used to achieve a smooth switching of the two control strategies.The results show that the composite control strategy compensates for the natural defect that the synovial observer is difficult to extract the back EMF in the low speed segment,and the total harmonic distortion of the stator current in the high-speed segment is effectively suppressed,and has good dynamic response performance and estimation accuracy in the full speed range.