Power efficient sliding mode control of SR motor for speed control applications

In this paper a novel method for speed regulation and tracking of Switched Reluctance Motor is proposed. The proposed method uses the concept of only energizing all those phases of the motor which can contribute to desired polarity of torque at one time for power saving. The suggested scheme is based on Sliding Mode Technique. A mathematical model of SR motor is derived for controller design purpose. The power efficiency is derived by not energizing all the phases at a given time; this is because not all the phases of SR motor can produce torque with the same polarity because of the particular motor construction. Thus our controller chooses the appropriate phases, at any control instant, to get the desired torque output with minimum phase currents. The speed regulation scheme is compared with the conventional sliding mode control taken from the public literature. Simulation results confirm the effectiveness of the proposed regulation controller. The proposed scheme reduces the power loss of SR motor. A tracking control based on the new scheme is also presented.