Performance Improvement of Switched Reluctance Machines Through Appropriate Design Choices

Switched reluctance machines can represent a valid alternative to synchronous and induction machines in various applications, thanks to their ruggedness, ease of mass manufacturability, low cost and fault tolerance. Nonetheless, this machine topology is generally associated to a number of weaknesses, mainly in terms of quality of torque delivery and acoustic noise emission. Advancements in power electronics and controls have led to extraordinary results in terms of mitigating these issues, even by implementing them on sub-optimal electromagnetic designs. Thus, if advanced controls are suitably combined to a proper electromagnetic design, then switched reluctance machines could potentially offer superior performance compared to other rare-earth-free motors. Based on the above, this paper reviews and quantifies, through purposely implemented design examples, how various design choices can strongly influence the torque ripple and vibration behavior in switched reluctance machines, showing how two-digit percent improvements can be attained through suitable design measures.