Sensorless Starting Control of Brushless Synchronous Starter/Generators by Using the Main Exciter as a Position Sensor

The main generator (MG) and the main exciter (ME) are mechanically coupled on the same shaft in the brushless synchronous starter/generator (BSSG), so MG and ME have the same mechanical rotation angles. According to this structural feature, ME is regarded as a position sensor of MG in this paper. Characteristics of rotor currents of ME brought by the rotating rectifier are analyzed and used to estimate the rotor position information of MG without the need of high-frequency signal injection and effects of reversible saliency of MG. Experimental results are presented.