End leakage flux of machine cores

Abstract

The leakage field at the core ends of a salient-pole machine is difficult to determine accurately owing to the complexity of the end profiles of the stator. The paper simplifies these profiles, thus making it possible to obtain the leakage flux by an analysis based on the assumption that the flux lines follow geometrical paths. As a corollary, the leakage fields at the core ends of induction motors are obtained by a modification of the analysis. The values of the leakage flux factor, K, for a range of machine parameters are given as a family of curves for typical salient-pole generators and induction motors, together with typical curves of the leakage flux density distribution at the stator-core end faces.