Study on Vibration by Electromagnetic Force in the End Portion of Large Capacity Cylindrical Synchronous Machines

—Improvement of Electromagnetic Force Estimation and Verification of Degradation on Coil Insulation—

Abstract

A new electromagnetic force analyzing method in end-winding is provided and evaluated by comparing to 3D- FEM electromagnetic analysis. Additionally, estimating method of end-winding vibration on load is suggested by measured data at factory test. Moreover, evaluating method for insulation degradation after operation is offered for large capacity cylindrical synchronous machines, where end-winding portion is the longest and electromagnetic forces on it is the greatest of all rotating machinery.