PMSM无传感器初始位置检测及低速运行研究

目前,永磁同步电机(PMSM)无位置传感器运行研究受到广泛关注。文章采用一种基于高频方波信号注入的方法实现PMSM无位置传感器启动以及低速运行。首先详细分析了高频方波信号注入检测原理,然后对注入的高频方波信号以及电流采样模式进行了改进。在估计的两相旋转坐标系轴向注入频率等于逆变器开关频率的高频方波电压信号,通过巧妙的安排定子电流采样模式,根据检测到的定子电流并结合注入的方波电压信号即可获得转子位置信息;采用Luenberger观测器对转子位置信息进行观测,以获得较为平稳准确的电机转速和转子角度估计值;利用电机的磁路饱和特性,实现基于高频方波信号注入法的PMSM无位置传感器转子初始位置检测。所提出的改进方法不依赖于准确的电机参数,不需要使用任何滤波器,信号处理过程简单易实现。仿真结果验证了该方法的正确性。

Research on PMSM Sensorless Initial Position Inspection and Low-Speed Operation

Nowadays, the PMSM sensorless control attracts more and more attention from many researchers. A method based on high frequency square wave injection algorithm is used in the PMSM sensorless start and lowspeed operation control in this paper. The principle of square wave injection method is analyzed in detail firstly. Then an improved high frequency square wave voltage is injected into the stator of the motor in the axial direction of the estimated two-phase rotating coordinate, and the stator currents are measured to extract the rotor position information with the help of the injected signal. Then a Luenberger observer is introduced to observe the rotor position to obtain steady and accurate estimated values of the speed and angle of the motor. The proposed method is independent of motor parameters and no filter is involved. Thus the signal processing is simple and easy to realize. Simulations have verified the validity of the method.