Calculation of 3D nonlinear stator temperature field after insulation aging and shelling for large synchronous generator based on FEM

A salient pole synchronous generator is taken for an example to be calculated in this paper. The 3D isoparametric finite element method and Newton-Raphson method are applied to compute the 3D thermal field while the flow field in stator ventilating grooves is a nonlinear field. At the same time, numerical simulation method is used to analyze the stator thermal field after insulation aging, by which the trend of temperature variation in each stator part is determined. Finally, the calculated results are compared with measured results and the accuracy meet the need of engineering application, which lay a theoretical foundation for online temperature monitoring and heat fault diagnosis.