考虑饱和效应的永磁同步电机全程无位置传感器控制

Whole Speed Range Sensorless Control of Permanent Magnet Synchronous Motor Considering Saturation Effect

针对永磁同步电机无位置传感器控制静止和低速时位置估计困难,采用恒电流变频(I/F)起动,可在不同负载下都能顺利起动。中高速阶段采用无迹卡尔曼非线性滤波器(UKF)进行位置估计,同时考虑了磁场的饱和效应和滤波器的滞后,采用时变电感参数和滤波器滞后补偿来提高位置估计精度。并利用转矩-功角自平衡特性,完善了I/F起动到UKF无位置传感器闭环控制的过渡策略,实现电流和转速的平滑切换。实验结果说明该策略可实现全程无位置传感器控制,并且在负载、转速变化过程中,估计位置无稳态误差。

To overcome the difficulty of position estimation for sensorless control of permanentmagnet synchronous motor(PMSM)in low-speed range,a start-up method called I/F is adopted.It canensure PMSM start up in different load conditions.Unscented Kalman filter(UKF)is used for positionestimation in middle to high-speed range.Meanwhile,considering saturation effect and filter delay,thevarying inductance and filter delay compensation are used to improve position estimation accuracy.Based on the torque-power angle self-stabilization mechanism,a smooth switching method thattransforms I/F starting method to UKF based closed loop sensorless control,is implemented to switchcurrent and speed smoothly.The experimental results demonstrate the whole speed range sensorlesscontrol is effective.During the changing processes of load and speed,the steady state error of estimatedposition can be eliminated.