3D transient temperature field analysis of the stator of a hydro-generator under the sudden short-circuit condition

In this study, Finite Element Method (FEM) is applied to calculate the 3D transient temperature field of the stator of a hydro-generator, SF125-96/15600, under the sudden short-circuit condition. 3D transient equation of the heat conduction and its equivalent functional equations are firstly presented. Then the sudden short current and transient heat generation of the stator are analysed and calculated. Moreover, all the parameters for the simulation such as the heat conductivity coefficients of the iron core and stator coils, heat convection coefficients of each surface as well as iron and copper losses are deduced. These parameters are verified to be reasonable by comparing the simulated temperature results with the measured in the stable state. Finally, the 3D transient stator temperature field of the hydro-generator under the sudden short-circuit condition is simulated. The variation of the temperature field and temperature rise of the key components is also predicted, on which online thermal monitoring of the stator and optimum design can be carried out.