基于新型高次谐波滤波器的SPMSM龙伯格观测器

Luenberger observer of SPMSM based on a new high-order harmonic filter

在使用龙伯格观测器对表贴式永磁同步电机(surface permanent magnet synchronous motor,SPMSM)进行无位置传感器控制时,逆变器的死区时间和转子空间结构将会引起反电动势中含有高次谐波,从而影响观测器的位置估计精度。提出一种新型的高次谐波滤波器——二阶复数低通滤波器(second-order complex low-pass filter,SOCLF),该滤波器在中心频率处零增益、无相位差,且对高频信号具有较好的抑制效果。首先,使用SOCLF对龙伯格观测得到的反电动势进行预处理,可以实现在反电动势基波信号不失真的前提下抑制反电动势中的高次谐波。其次,通过锁相环提取预处理后的反电动势信号中的位置信息。最后,搭建试验平台,对反电动势进行谐波分析。结果表明,加入SOCLF预处理可以抑制其含有的高次谐波。同时,电机估计位置误差有所减小,证明了该方法的有效性。

When using the Luenberger observer for sensorless control of surface permanent magnet synchronous motors(SPMSM),the dead time of inverter and rotor spatial structure caused high harmonics in the back electromotive force(EMF),affecting position estimation accuracy of the observer.A new highorder harmonic filter,the second-order complex low-pass filter(SOCLF),has been proposed.This filter has zero gain and no phase difference at the center frequency and effectively suppresses high-frequency signals.Firstly,the back EMF obtained from the Luenberger observer was preprocessed by the SOCLF,which can suppress the higher harmonics in the back electromotive force without losing the fundamental wave signal.Secondly,the phase-locked loop extracted position information from the preprocessed back EMF signal.Finally,an experimental platform has been built to analyze the harmonics of the back EMF.It is shown that the SOCLF preprocessing suppresses higher harmonics in the back EMF and position estimation error of the motor decreased,which proves the effectiveness of the method.