Research on Distributed Magnetic Circuit Calculation of Halbach Magnetized Permanent Magnet Generators

Abstract

Because of the flexibility and clear physical concept, magnetic circuit calculation method (MCCM) is preferred during the early stage of the electromagnetic design of generators and motors. Based on the analysis of magnetic field distribution in halbach magnetized permanent magnet generator (HMPMG) by finite element method (FEM), this paper proposes a distributed magnetic circuit calculation (DMCC) for HMPMG. Because of the low permeability of permanent magnet (PM) material, the DMCC for HMPMG is quite different from that for electrical excitation generator. By dividing half-pole generator model into sub-sections along radial and circumferential direction with circumferential equi-interval nodes in air gap, the DMCC for HMPMG employs iteration to calculate magnetic flux density on air gap nodes. In the end, the validity and accuracy of DMCC are proved by FEM.