改进SMO的高速永磁同步电机无传感器控制研究

Research on Sensorless Control of High Speed Permanent Magnet Synchronous Motor With Improved SMO

对于高速永磁同步电机(PMSM)无位置传感器控制研究中,针对传统滑模观测器(SMO)存在滑模抖振,以及在观测到的反电动势信号经过低通滤波器(LPF)消除高频谐波造成的相位滞后的问题和高速下由于电流采样造成的数字延时问题,提出一种基于二阶广义积分器-锁频环(SOGI-FLL)的改进SMO方法。针对上述问题,首先利用双曲正切函数来代替sign函数,来减少滑模的抖振;然后引入SOGI-FLL代替LPF来对观测的反电动势进行滤波,进而消除相位滞后。其次在此基础上补偿由于数字延时造成的角度误差。最后搭建PMSM实验平台验证此方法的可行性,实现PMSM无位置传感器控制在中高速域转子速度和位置的准确估算。

In the research of sensorless control for high-speed permanent magnet synchronous motors(PMSM),an improved sliding mode observer(SMO)method based on second-order generalized integrator frequency locked loop(SOGI-FLL)is proposed to address the issues of sliding mode oscillation in traditional sliding mode observers,phase lag caused by high-frequency harmonics eliminated by low-pass filters(LPF)in the observed back electromotive force signal,and digital delay caused by current sampling at high speeds.In this research,in response to the above problem,the hyperbolic tangent function is used to replace the sign function to reduce sliding mode chattering.Then,SOGI-FLL is introduced to replace the LPF to filter the observed back electromotive force,thereby eliminating phase lag.Secondly,compensate for the angle error caused by digital delay on its basis.Finally,a PMSM experimental platform is built to verify the feasibility of this method,achieving the precise estimation of rotor speed and position of PMSM without position sensor control in the medium and high speed domain.