Rotor position detection scheme for synchronous reluctance motorbased on current measurements

摘要

A rotor position detection scheme which utilizes thecharacteristics of the synchronous reluctance motor is proposed. Inparticular, the dependence of the self and mutual inductances on therotor position is utilized. The motor currents are controlled by atransistor inverter in the manner of hysteresis current control. Theinverter switching creates ripples in the phase currents. The ratechange of current in the ripples is then detected and converted to arotor position signal. The proposed scheme is aimed at providing rotorposition information particularly at low rotor speed, even at zero rotorspeed. Numerical analysis of the rate change of the phase current of thesynchronous reluctance motor is also discussed