永磁同步电机无位置传感器控制策略研究

Research on sensorless control strategy of PMSM

针对电子水泵用永磁同步电机无传感器控制系统中调速存在超调、抖振和响应慢的问题,采用一种混合滑模变结构的速度环和龙伯格观测器的PMSM无传感器控制算法.在转速环环节设计基于新型趋近律的滑模速度控制器,在传统指数趋近律的基础上,在等速项中加入运动点的运动误差,采取双曲正切函数替代比较切换函数,改善趋近滑模面运动过程中的收敛速度和抖振抑制能力.采用线性控制结构的龙伯格观测器结合锁相环,应用到无传感器控制系统中,改善估算转速抖振问题及稳定性.仿真结果表明,在电机空载启动和外加扰动工况下,该算法可有效提高永磁同步电机无传感器控制系统转速的跟踪效果,改善转速的超调与抖振问题,同时提高系统的抗外部干扰能力.

Aiming at the problems of overshoot,chattering and slow response in the sensorless control system of permanent magnet synchronous motor(PMSM)for electronic water pump,PMSM sensorless control algorithm based on hybrid sliding mode speed controller and Luenberger observer was proposed.In the speed loop,a sliding mode speed controller based on the new reaching law was designed.On the basis of the traditional exponential reaching law,the motion error of the moving point was introduced into the constant velocity term,and the hyperbolic tangent function was adopted to replace the comparison switching function,so as to improve the convergence speed and chattering suppression ability of the sliding mode.The Luenberger observer of the linear control structure combined with the phase-locked loop was applied to the sensorless control system,in order to improve the chattering problem and stability of the estimated speed.The simulation results show that under the no-load starting and external disturbance conditions of the motor,the algorithm can effectively improve the speed tracking effect of PMSM sensorless control system,improve the speed overshoot and chattering problems,and enhance the anti-interference ability of the system.