考虑电感不对称的LFSPM电动机无位置传感器控制与分析OA

To solve the problem of AC components of the three-phase inductance asymmetry of linear motors caused by the unique longitudinal end effect in the position and speed estimation errors of sensorless control,the improved phase-locked loop(PLL)based on second-order notch filter was proposed for linear flux-switched permanent magnet(LFSPM)motor.The mathematical model of the LFSPM motor with considering inductance asymmetry was established,and the sliding mode observer was designed based on the stationary coordinate system.According to the analysis results,due to the inductance asymmetry,the extended back electromotive force could contain positive and negative sequence components,resulting in AC components in the PLL position error that could not be suppressed by conventional PI controllers.The principle of the improved PLL suppressing the AC components of position error was theoretically explained.The simulation model of the LFSPM motor sensorless control system was built using MATLAB/Simulink,and the sensorless control effects of the conventional PLL and the improved PLL were discussed.The experimental platform was constructed to test the proposed control strategy.The results show that compared with the conventional sensorless control methods,the improved PLL scheme based on the second-order notch filter can effectively improve the sensorless control accuracy of the LFSPM motor with reducing the speed error by 35.71％,the position error by 44.46％and the thrust ripple by 12％,respectively.