基于自适应滑模观测器的PMSM无位置传感器研究

PMSM sensorless control based on adaptive sliding mode observer

滑模观测器是永磁同步电机(permanent magnet synchronous motor,PMSM)无位置传感器研究中最常用的一种方法。为解决传统滑模观测器的抖振以及反电动势随转速变化而造成的位置估计精度问题,设计了一种自适应滑模观测器。以边界层随转子速度变化的正弦饱和函数取代符号函数,抑制了观测器的抖振;同时通过在观测器中引入一个与转子转速相关的反馈增益,得到了包含转子信息的等价磁链观测值,避免了反电动势估计位置引起的误差;构建李雅普诺夫函数证明了观测器的稳定性。实验结果验证了所设计的自适应观测器在减小抖振、提高观测精度方面具有有效性。

Sliding mode observer is one of the most commonly used methods in permanent magnet synchronous motor(PMSM)sensorless research.In order to solve the problem of position estimation accuracy caused by chattering and the back electromotive force(EMF)changing with the rotor speed in the traditional sliding mode observer,an adaptive sliding mode observer is designed in this paper.The sign function is replaced by a sinusoidal saturation function whose boundary layer is changing with the rotor speed,then the chattering of the observer is suppressed.At the same time,by introducing a rotor speed-related feedback gain in this observer,the equivalent flux observation value including the rotor information is obtained,and the error caused by the position estimation of the back EMF is avoid.The stability of the observer is proved by constructing the Lyapunov function.The experimental results verify the effectiveness of the designed adaptive observer in reducing chattering and improving the observation accuracy.