改进型滑模观测器的永磁同步电机无传感器控制策略

A Sensorless Permanent Magnet Synchronous Motor Control Strategy for Improved Sliding Mode Observers with Stator Parameters Identification

针对永磁同步电机(PMSM)实际运行时定子电阻和电感常发生随机变化的情况,提出了一种可进行永磁同步电机无传感器控制的定子电阻和电感在线辨识的改进型滑模观测器。为了削弱系统高频抖振,用近似饱和函数代替开关函数;基于Lyapunov稳定性理论,在保证观测器稳定性的同时,进行定子电阻和电感参数辨识,并将其反馈到观测器模型,实时修正观测器模型参数,从而提高估算精度;采用锁相环技术计算出转子位置和速度信息,将其反馈到电机控制系统。数值仿真结果表明,改进型滑模观测器能够快速、准确地跟踪转子位置,估算转子速度,且能辨识定子电阻和电感值并进行反馈,实现永磁同步电机无传感器控制。

An improved sliding mode observer（SMO）with the feature of identifying stator parameters in real time for permanent magnet synchronous motor（PMSM）control is proposed to address the case that the stator resistance and the inductance randomly change when a PMSM is running.An approximate saturation function is used as the switch function in the improved SMO control system to reduce the system chattering.The improved SMO estimates the stator resistance and inductance values by employing Lyapunov stability theorem on the premise of ensuring the stability of the observer and feedbacks them to the PMSM model to improve the estimation accuracy of rotor＇s position and velocity.The rotor＇s position and velocity information are estimated from the back electromotive force based on the principle of phase-locked loop.Simulation results show that the improved SMO quickly and accurately tracks the position and the velocity of a rotor,and has an attractive dynamic performance by estimating the resistance and inductance of the stator in real time and correcting the PMSM model.