A Comprehensive Review of Torque and Speed Control Strategies for Switched Reluctance Motor Drives

Abstract

Switched Reluctance Motors (SRMs), outfitted with rugged construction, good speed range, high torque density, and rare earth-free nature that outweigh induction motors (IM) and permanent magnet synchronous motor (PMSM), afford a broad range of applications in the domain of electric vehicles (EVs). Standard copper magnetic wire and low-carbon steel laminations are used to construct SRMs, which give them high efficiency in the range of 85–95%. Despite SRM's desirable features over traditional motor-speed drives, high torque ripples and radial distortions constrain their deployment in EVs. Precise rotor position is imperative for effective management of the speed and torque of SRMs. This paper provides an illustrative compendium on review of the torque-speed control and ripple mitigation techniques using design enhancements and control methods for SRM drives for EV applications. The various schemes were evaluated on their performance metrics-operational speed range, control complexity, practical realization, need for pre-stored parameters (lookup tables of current, inductance and torque profiles) and motor controller memory requirements. The findings provide valuable insights into balancing the gains and tradeoffs associated with EV applications. Furthermore, they pinpoint opportunities for enhancement by analyzing the cost and technical aspects of different SRM controllers.