Search

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. Index Terms--Four-quadrant, pulse injection, sensorless, switched reluctance.

This paper presents a hybrid sensorless controller used with both the classical eight-switch converter and a reduced six-switch converter topology for switched reluctance motor (SRM) drives. The hybrid sensorless scheme consists of a sliding mode observer (SMO)-based position sensorless approach for high speeds along with a low-resolution discrete sensor for low speeds and standstill. The hybrid position estimation switches between the SMO and the low-resolution sensor according to the speed sign and the position error difference between the SMO and the low-resolution sensor. The experimental results show the robustness of this hybrid low-cost control approach with the two converter topologies. Index Terms--Converter topology, hybrid, sensorless, switched reluctance.

A four-quadrant sensorless controller for switched reluctance motor (SRM) drives is presented in this paper. The drive system with appropriate turn-on and turn-off angles for each operating quadrant delivers excellent dynamic performance over a wide speed range including zero speed. The problems associated with practical implementation especially at low and zero speeds have been addressed and overcome with engineering solutions. Experimental results for a 1-kW SRM obtained on a dSPACE-based system are presented along with useful guidelines for practical implementation. Index Terms--Four-quadrant control, position and speed estimations, sensorless control, sliding-mode observer, switched reluctance motors (SRMs), zero-speed control.