Switched Reluctance Motor Modeling and Loss Estimation Review

Abstract

Switched reluctance machines (SRM) are an alternative to conventional and permanent magnet (PM)-based machines. They are simple, robust and fault tolerant, and able to reach very high speeds with high efficiency. However, they operate with high torque pulsation and are noisy. Also, a nonconventional power converter type and specific control schemes must be included. Furthermore, SRM operation is characterized by high nonlinear features, which makes it difficult to be modeled and controlled. SRM energy conversion principles are a keystone to understand its operation. SRM efficiency increases with speed, where core and mechanical losses are more significant. For this machine, core loss estimation is a complex task, due to the nonlinear behavior of the magnetic materials. In addition, flux waveforms are not sinusoidal and particular waveforms appear in different core sections. Empirical formulas are usually considered in core loss estimation, but this is insufficient for SRM.