Analysis of End Zone Magnetic Field in Generators and Shield Optimization for Force Reduction on End Windings

This paper compares analytical methodologies, 2-D and 3-D finite-element techniques as well as methods based on image theory for the evaluation of leakage field on end windings of electrical machines. A particular 2-D numerical method based on finite element representation and axiperiodic symmetry has shown the best performance. The method has been applied to the geometry optimization of shields enabling force reduction on end windings of a permanent magnet machine.