A Novel Winding Switching Control Strategy of a Consequent-Pole Ferrite-PM Hybrid-Excited Machine for Electric Vehicle Application

In this article, a novel winding switching control strategy is proposed to extend the speed range of a consequent-pole ferrite-permanent magnet hybrid-excited machine (CPFPM-HEM) for electric vehicle application. The key is that in low-speed range, the ac armature winding and dc field winding are connected in series to achieve large starting torque, while in high-speed range, dc field winding is injected with adjustable dc currents to realize variable speed constant voltage of ac armature winding. Furthermore, consequent-pole rotor is used to reduce the usage of the permanent magnet (PM). In the meantime, ferrite PMs are used to replace rare-earth PMs to reduce the cost with the shortage of rare-earth resources. In this article, the machine configuration, operation principle with dual excitation sources, flux modulation principle, and winding switching strategy are illustrated in detail. Then, the electromagnetic performance of the CPFPM-HEM in different speed ranges is investigated. Finally, the speed range extension with winding switching strategy is verified by the Maxwell/Simplorer co-simulation.