This paper presents a new and novel method which is designed to detect the rotor position at standstill and also low speeds in switched reluctance motor. In this method a small capacitor is connected in series with the motor windings. The supply voltage in conjunction with the drive transistor produces short pulses for this series connection. The phase inductance varies with the rotor position, therefore the rise time of the voltage produced on the capacitor changes. Now the capacitor voltages are compared with a pre-set voltage value and the rotor position is detected at standstill mode. It then continues to sense the rotor position while the motor running by applying the same procedure but only to the un-energized phases winding. The results obtained demonstrate the feasibility and practicability of the method.
H. Moradi Cheshmeh baygi and E. Afjei
Dept. Electrical & Computer Engineering
Shahid Beheshti University, Saadat Research Institute