Abstract
A lot of studies on reducing cogging torque of permanent magnet machines have so far been carried out. However, the most of them are objected for the radial-gap type machines, which have wide application in various fields. In this study, the various techniques of reduction of cogging torque that can be used in rotor part of an axial-gap generator are examined numerically by using the three-dimensional finite element method. It is shown that the reduction of the cogging torque is difficult in the axial-gap type machine rather than the common radial-gap machine. The analyzed results with the three-dimensional finite element method are compared with ones of a reference model of the axial-gap permanent magnet machine, and the improvements are demonstrated.
