Computation & Analysis of End Region EM Force for Electrical Rotating Machines using FEM

In the recent designs of electrical rotating machines, the emphasis are to have high capacity and electrical loading without comparable increase in size. Therefore the end-winding support structure becomes more significant to withstand with large stress developed due to electromagnetic forces. The end winding support structure of large rotating machine is designed to ensure that the stress in copper or insulation of the end windings do not exceed acceptable limits under steady state and transient conditions. The reliability of end-region structure is proportional to the EM forces therefore predetermination of the parameters of these forces may quit useful for the selection of end ring material and deciding the insulation level for the proposed structures. In this paper, 3-D finite element method has been used to compute and analyze the electromagnetic forces across the end region structure of rotating machines. The computed results are in good agreement with the reported results.