PMSM无位置传感器控制中数字滑模观测器抖振现象分析与抑制

通过对永磁同步电机(PMSM)反电动势滑模观测器观测结果进行加窗快速傅里叶变换(FFT)频谱分析,发现抖振信号频谱范围较宽、幅值较大,观测结果无法直接使用,低通滤波器使得观测信号发生变化,难以精确补偿。本文提出了一种以电流和磁链为观测对象的扩展滑模观测器,磁链观测结果由磁链实际值和经过滤波后的抖振信号组成。根据磁链观测结果的频谱分析,抖振现象的影响可以忽略不计,转子角度可以由磁链观测结果直接计算,不需要低通滤波,避免了相位滞后。着重分析了速度估计误差对观测结果和转子角度计算的影响,并以此为基础进行反馈矩阵计算。仿真和实验结果表明该方法能够准确计算出电机的位置和速度,使系统具有良好的稳态精度和动态性能。

Chattering Phenomenon Analysis and Suppression of Sliding Mode Observer in PMSM Sensorless Control

Spectrum analysis of PMSM back EMF sliding mode observer(SMO) based on windows FFT shows spectrum range of chattering signal is large and the amplitude is high. The result can't be used directly and must be filtered. But the signal changes after passing the low band filter and the compensation is difficult. This paper presents an extended SMO,of which the state variables are current and flux. The observed flux is composed of the real flux and the filtered chattering signal. The spectrum analysis shows the i...