Optimal PM Numbers and Stator/Rotor Pole Number Combinations in Asymmetric Consequent-Pole Hybrid Excited Flux-Reversal Machines

This paper investigates the influence of permanent magnet (PM) numbers and stator/rotor pole number combinations (S/R combinations) on two asymmetric consequent-pole hybrid excited flux-reversal machines (ACPHEFRMs). For ACP-HEFRMs, radially-magnetized PMs and small iron teeth are arranged alternately on each stator pole. Moreover, PMs are radially-magnetized in the same direction on the same stator pole, while in the opposite direction on the adjacent poles. AC armature windings and DC excitation windings are wound on each stator tooth separately on the stator tooth. The phase shift between PM and DC produced magnetic field phase flux-linkages (PM-DC phase shift) in ACP-HEFRMs with different PM numbers is highlighted and the phase shift elimination is generalized to obtain the optimal S/R combination for the first time. With the objective of maximizing average torque, genetic algorithm has been adopted in global optimizations to determine the optimal S/R combination and PM numbers for both ACP-HEFRMs. Comparisons are made on both machines regarding torque, torque ripple, and flux-regulation capability.