Obtaining the magnetic characteristics of 3/4 salient-pole brushless DC machine from 3-D FEM analysis

摘要

This paper deals with accurate electromagnetic field analysis of 3/4 salient-pole structure brushless DC generator (BLGD) with concentrated stator winding, which does not use a permanent magnet in the rotor. The permanent magnet is replaced with assisted field coil in the rotor. To evaluate the generator performance the numerical technique has been utilised. In the numerical analysis, 3-D Unite element (FE) analysis has been carried out to confirm the accuracy of the predicted flux-linkage characteristics and, also an improved 3-D hybrid method coupling the FE method and boundary integral equation method to confirm the accuracy of the 3-D FE analysis has been carried out. Afterward, a series of experimental tests are performed to obtain the magnetic characteristics of the 9/6 configuration by same structure, comparing, correcting, and discussing the results with those of 3-D FEM analysis.