高分辨的永磁无刷直流电机转子零初始位置检测方法

A High Resolution Detecting Method for Rotor Zero Initial Position of Sensorless Brushless DC Motor

通过对无刷直流电机(BLDCM)的电磁场有限元分析,求出了由于饱和效应定子绕组相对于转子不同位置的电感变化曲线。据此分析并找出了给定子绕组施加不同的电压矢量时无刷直流电机功率驱动器直流母线电流响应的规律,提出了高分辨转子零初始位置的判断规则和实施步骤,转子定位误差小于±7.5°电角度。本方法也适用于无刷直流电机低速运行时的转子位置判断,从而实现BLDCM无振荡起动和低速可靠运行。样机试验验证了这一方法的可行性。

Based on finite element analysis to electromagnetic field of Brushless DC Motor （BLDCM）, stator winding inductance curves relative to different rotor position due to the saturation effect are showed. And then current response regularity on DC bus of BLDCM power driver is analyzed when different voltage vectors are applied to the stator windings. The judgment rules and implementation steps for high resolution rotor zero initial position are presented and so rotor positioning error is less than 7.5 degree electrical angle. The method is also applicable to BLDCM running at low speed, so that reliable operation of BLDCM is realized without oscillation in starting and low speed. Prototype test was made to prove the feasibility of the method.