针对永磁同步电机,基于浸入与不变(immersion and invariance,I&I)理论构建反电动势和负载转矩观测器,从而提出无传感控制方案.首先,用低通滤波器对电机的电压与电流信号进行滤波处理;然后,通过分析滤波前后的信号,应用I&I理论建立不变流形,根据不变流形的稳定性与可控性,提出系统自适应律来构建反电动势观测器,并根据得到的反电动势的估计值,采用反正切法求解转子位置和速度的估计值;其次,基于I&I理论利用转速估计值构建负载转矩观测器以得到负载转矩估计值;最后,采用反步法基于估计的转速与负载转矩设计了转速环控制器并证明了闭环稳定性,实现了永磁同步电机的无传感器控制.仿真研究结果表明,在带有未知负载扰动的情况下,与传统PI控制器下的滑模观测器法相比,基于I&I观测器法具有更好动态响应能力和更强的鲁棒性.
Sensorless Control of Permanent Magnet Synchronous Motor Based on Immersion and Invariance Observer
For permanent magnet synchronous motors(PMSM),a sensorless control scheme is proposed based on the immersion and invariance(I&I)theory to construct observers for back electromotive force(back-EMF)and load torque.Firstly,a low-pass filter is used to filter the signals of motor voltage and cur-rent.Then,by analyzing the filtered and unfiltered signals,an invariant manifold is constructed using the I&I theory.According to the stability and controllability of the invariant manifold,an adaptive law is proposed to construct an observer for back-EMF.Based on the estimated back-EMF,the rotor position and speed are estimated using an arctangent method.Subsequently,using the estimated speed,a load torque observer is constructed based on the I&I theory to obtain the load torque estimation.Finally,a speed loop controller is designed based on the estimated speed and load torque using the backstepping method,and the closed-loop stability is proved.The simulation research results indicate that,in the presence of unknown load disturb-ances,the I&I observer-based method exhibits better dynamic response capability and stronger robustness compared to the sliding mode observer method under traditional PI control.
permanent magnet synchronous motorimmersion and invarianceinvariant manifoldload torque estimationsensorless control
万方数据
维普
