Switched reluctance motors (SRMs) have gained considerable attention as rare-earth-free machines; however, their control systems remain relatively complex. Recently, a current vector control approach used for other AC motors was applied to SRMs, and its mathematical model was clarified. However, this method assumed constant inductance, neglecting the effects of magnetic saturation. Based on this assumption, the current vector control employs a PI controller designed using pole-zero cancellation. However, achieving high torque output in an SRMs require a large stator current (i.e., active excitation), which inherently increases the likelihood of magnetic saturation. Consequently, during current vector control, the magnetic saturation at the high torque levels causes insufficient pole-zero cancellation, leading to system instability. Further, high-gain control for fast torque response is difficult to achieve. Based on our previously proposed torque derivative value manipulated type torque feedback control system, a robust torque control scheme tolerant to inductance variations is proposed. The effectiveness of the proposed method is verified experimentally.
Kawamura et al. (Thu,) studied this question.