Constant volts per hertz control of ultra-high speed switched reluctance machines

Abstract

Ultra-high speed machines have become more and more interesting to researchers in the past few decades. Switched reluctance machines (SRMs) are very attractive to researchers due to their simple geometry. However, traditional control methods are not suitable for ultra-high speed applications because of their super-high switching frequency. In this paper, a constant volts per hertz control for ultra-high speed SRMs over the entire speed range from 0 to 1 million rpm is proposed. The main idea is to reach one pulse per stroke over the entire speed range by controlling the supply voltage over rotational speed to be a constant value and fixing the switching on and off angles close but before the machine goes into saturation. A Simulink closed loop control model is built based on the finite element model to validate the proposed control. The results show that the switching frequency is decreased to a minimum value.