Three-Switch Reconfigurable Winding Power Converter and Online Mode-Changeover Methods for SRM Speed Range Extension

This article presents a new three-switch reconfigurable winding power converter and its online mode-changeover methods for switched reluctance motor (SRM). The suggested reconfigurable winding drive allows the motor to operate in both winding series and parallel modes. The series mode is suitable for low-speed and high-torque operation, while the parallel mode can extend the speed range and enhance the current modulation capability at high speed. First, the device types of the mode-changeover switches have been carefully considered for selection. The two working modes and typical operating states for the proposed power converter are illustrated. Then, the three-phase current-to-zero switching method is proposed to suppress the possible voltage spikes during the mode-changeover process. In addition, an adaptive fuzzy logic (AFL) speed controller is developed by combining the variable parameter proportional integral (PI) and fuzzy logic controller to reduce the speed shock. Finally, the simulation model and the experimental platform for the reconfigurable winding drive system are established to verify the effectiveness of the new three-switch power converter and the online mode-changeover methods.

I. Introduction

Due to its uncomplicated design, robust starting torque, and reliability, switched reluctance motor (SRM) has emerged as a potential choice for applications in electric vehicles (EVs), wind power generation, and household appliances [1], [2]. Nevertheless, SRM also has inherent disadvantages, such as substantial torque ripple and relatively low power density. Besides, the capacity to control current diminishes with rising speed, making it challenging to maintain consistent power output at high speed. Consequently, significant efforts have been devoted to enhancing its performance in recent decades [3], [4].