Multiphase Modular Permanent Magnet Drive System Design and Realization

Modular permanent magnet machines are gaining popularity for their ease in assembling the stator pieces and phase windings. In this paper, a multiphase modular permanent magnet machine with a corresponding drive topology is proposed as a high performance drive system. The machine stator modules are fabricated by soft magnetic composite (SMC) material, which benefits large scale machine fabrications by the one punch fabrication process for the modules. Moreover, its isotropic material property can be exploited for various machine structure design compared with the 2D flux distribution of typical iron laminations. By making use of a concentric winding configuration, the stator structure is simplified with the benefit of less end winding loss. With a multiphase design, the system can survive under major fault conditions. A fault tolerant capability for up to two phase open and several switch failure combinations have been validated by an actual five phase motor drive system realization.