A Novel Flux-Controllable Vernier Permanent-Magnet Machine

By artfully integrating the vernier structure and the DC field winding together, a novel flux-controllable vernier permanent-magnet (FCVPM) machine is proposed, which has the merits of offering high torque output at low speed operation and the flux weakening control at high speed operation. The key is to use the flux modulation poles to modulate the high speed rotating field of the armature winding and the low speed rotating field of the PM rotor, thus achieving the gear effect for high torque output. Also, the DC field winding is specially incorporated into the stator embedded slots, which can effectively weaken the airgap flux density, thus realizing the flux weakening control at high speed operation. By using the time-stepping finite-element-method, the basic characteristics, low speed and high speed operation performances of the machine are analyzed, which verifies the validity of the machine design. Index Terms—Finite-element-method (FEM), flux control, permanent-magnet machine, Vernier structure. I