Four-Quadrant Pulse Injection and Sliding-Mode-Observer-Based Sensorless Operation of a Switched Reluctance Machine Over Entire Speed Range Including Zero Speed

The objective of this paper is to present a sensorless position estimation technique for switched reluctance machines operating in dynamic modes over a wide speed range including zero speed. The technique combines two different methods to deliver high-resolution position information over the wide speed range. At zero and low speeds, a voltage pulse injection method is used to estimate the rotor position in all four quadrants. For higher speeds, a sliding-mode-observer-based algorithm is used and combined to work with the low-speed algorithm. Experimental results demonstrate the effectiveness of this new combined technique that has four-quadrant operation capability