Form Factors and Harmonic Imprint of Salient Pole Shoes in Large Synchronous Machines

摘要

This article presents a review of the connection between salient pole shoe shapes and form factors that model satiency affects in synchronous machine design programs. Additionally, the impact of the pole shape on the harmonic contents of the air-gap flux density waveform is examined. The properties of different pole shoes are assessed with 2-D finite element analysis in the working environment of a large hydro-electric generator topology. The influence of magnetic saturation is particularly emphasized. Linear models for the calculation of form factors are established. It is concluded that the choice of pole shoe design typically must be a compromise between a high field and direct axis form factor and a low total harmonic distortion.