基于励磁电压方波调制的三级式同步起动/发电机转子初始位置估算方法

The existing three-stage synchronous starting/generator initial rotor position estimation methods based on high-frequency injection face failure risk due to high-frequency attenuation. Based on the mutual inductance between the stator and rotor of the main motor, this paper proposes a three-stage synchronous starting/generator initial rotor position estimation method based on the excitation voltage square wave modulation. The excitation voltage is used as the carrier wave, and the low-frequency response current at the stator side of the main motor is extracted for the initial rotor position estimation after the low-frequency square wave modulation. When the three-phase lower tube of the stator inverter is activated, the method comprises into two steps: first, the excitation voltage is modulated by low-frequency square wave, and the low-frequency induction current of the stator of the main motor is collected to pre-estimate the initial position of the rotor; Second, by pre-estimating the initial position, the relevant current characteristics before and after the excitation voltage outage are analyzed to obtain the final initial position containing the magnetic pole information. The proposed method processes the collected low frequency current through virtual angle transformation and variance. Experiments show that the proposed method has high estimation accuracy.