Indirect startup rotor position sensor for synchronous reluctance motor

This paper presents a new indirect method of sensing the rotor positions in a synchronous reluctance motor at zero speed. The method is based on a special diagnostic switching control of the drive converter. The induced phase voltages and currents from this diagnostic signal is used to determine the position of the rotor. Variations of the method also work accurately and with robustness at all speeds. This method requires no additional hardware, other than the drive circuitry and microcontroller. The theoretical foundations of the method are presented and the experimental results are shown to verify the practicality of the method