Switched Reluctance Motor Characteristics

The growing environmental concerns and the need to reduce greenhouse gas emissions are accelerating the electrification of road transportation, positioning electric vehicles (EVs) as a key solution for improving energy efficiency in the automotive sector. Traction electric machines play a crucial role in meeting the demanding performance requirements of EV powertrains, including high efficiency over a wide speed range, high torque and power density, robustness, and fault tolerance. While permanent magnet synchronous motors (PMSMs) currently dominate the market due to their superior performance, their dependence on rare-earth materials raises significant concerns related to cost, supply chain vulnerability, and environmental impact. As a result, rare-earth-free electric machines have gained increasing attention. This article presents a comprehensive review of switched reluctance motors (SRMs) as a promising alternative for electric vehicle applications. The operating principles, structural characteristics, power converter requirements, and basic control strategies of SRMs are discussed, along with their advantages and inherent limitations, such as torque ripple and acoustic noise. Furthermore, recent advances in non-conventional SRM topologies and design approaches aimed at improving torque density, power factor, and noise reduction are reviewed. The analysis highlights the potential of SRMs to contribute to sustainable electric mobility, particularly in applications where robustness, wide constant power speed range, and cost-effectiveness are critical.