The Research And Numerical Analysis Of The Coupled Electromagnetic-Thermal Field In The End Region Of Turbogenerator

Targeting on solving the temperature-rising problem of structure components in the end region of a 1000 MW turbogeneratort, the paper makes a systematic and deep research on the eddy current, loss and temperature fields of end structure component in the end region of turbogenerator. The main works and achievements are as following:The paper investigates THDF125/67 imported from SIEMENS Corporation. The mathematic model and equivalent function of the boundary value problem are modelled. Dynamic potential A andφare adopted as solving variable. After discretization of function using Calerkin approach, the finite element equations are obtained. The FE analysis software is compiled with Visual Fortran. By loading the eddy current losses into temperature field as thermal source, which is calculated by the analysis of traveling wave eddy current field, the FE numerical analysis of temperature field in the press circle are solved. Under rating-shorten operation, the test results validate the simulation analysis, which confirms the application value of the method and software.Applying the method mentioned above, the paper makes a systematic research on the eddy current-thermal coupling fields in the end region of the turbogenerator under other typical operations, such as empty load, rating load and leading phase operations and so on. The study provides a theory analysis criterion for the corresponding engineering design and opeation.According to the practical requirements of engineering analysis of the turbogenerator, the paper also detailed a 3D finite element analysis method for the eddy current-thermal coupling fields, which is verified by corresponding benchmark problems. At the same time, combined the FE software ANSYS with other CAA,CAD software and self-written Fortran software, the actual model of end region of turbogenerator. The paper performed the numerical analysis of the coupling fields in the completed three dimensional under empty load operation. The numerical analysis result fits with the result of traveling wave eddy current-thermal coupling fields. It provides another alternative analysis method for engineering to research the temperature rising in the structure component in the end region of turbogenerator.