Analysis of Large Turbine Generators by Nonlinear Quasi Three-Dimensional Electromagnetic Field Analysis

Abstract

An analysis method of quasi three-dimensional magnetic field of large turbine generators is presented. The presented method is based on sinusoidal approximation for potentials distribution of peripheral direction and anisotropic modeling of the iron teeth and stator slots. By the presented analysis, three-dimensional eddy current and magnetic flux, which is distributed in the turbine generator body and end portions, with considering non-linearity of BH curves of iron cores. Calculated eddy current and magnetic flux densities are shown to validate the method by comparison with measured ones of a 71MVA air cooled turbine generator.