Improved Harmonic Current Injection Control Strategy for DC-Biased-VRM Based on Current Orthogonal Component Distribution to Enhance Output Torque

This article proposes an improved harmonic current injection control strategy for dc-biased Vernier reluctance machine based on current orthogonal component distribution to enhance output torque, thereby improving the output efficiency of the machine. The effect of the interaction between the harmonic current and the inductance on average torque of the machine is analyzed. Then, a current distribution ratio with the maximum torque/current ratio is given, which can effectively increase the output torque of the machine. Based on this current ratio, a novel distribution method of harmonic current orthogonal component is proposed to provide reference value of harmonic current injection. Furthermore, in order to realize the precise injection control of amplitude and angle of harmonic current, a harmonic current orthogonal component tracking strategy with advanced angle compensation is proposed. The improved harmonic current injection control strategy presents advantages of high current control accuracy and wide applicable speed range. In addition, the parameter design of the method is relatively simple. Finally, the conclusion is verified by experiments.