Modeling and Analyzing a Novel Dual-Flux-Modulation Consequent-Pole Linear Permanent-Magnet Machine

A novel dual-flux-modulation consequent-pole linear permanent-magnet (DFM-CP-LPM) machine is proposed in this paper, which can be regarded as the combination of a linear flux-switching PM machine and a linear vernier PM machine. Via two sets of interoperable PMs mounted on both the primary and the secondary, the proposed machine can work in a dual-flux-modulation mode, achieving higher thrust density. Meanwhile, the consequent-pole structure is introduced, reducing approximately half of the PM usage compared to a conventional surface-mounted linear PM vernier machine (LPMVM), which will greatly reduce the cost. In this paper, the configuration and the operation principle of the novel DFM-CP-LPM are presented. Then the optimization and several thrust ripple reduction methods are introduced to improve the performance of the machine. Thermal analysis is also carried out to check the demagnetization risk of primary PMs, due to the heat from coils. Finally, the proposed machine is compared to a conventional LPMVM and a consequent-pole linear vernier permanent magnet machine with only PMs set on the secondary. The results verify the superiority of the proposed DFM-CP-LPM.