Calculation of rotor temperature field for huge hydro-generator

In this paper, a huge air-cooled hydro-generator was studied. In order to accurately calculate the loss and temperature distribution of the rotor, the 2D electromagnetic field model was established, and then the additional loss of the rotor pole surface under rated voltage was calculated by this model. Based on that, the 3D temperature field model of the hydro-generator was also established and the temperature distribution of the rotor was obtained. The results show that the additional loss of the rotor pole surface would influence each part temperature of the rotor, and the influence on pole surface temperature is especially greater. The conclusions could provide theoretical basis for the accurate temperature calculation of huge hydro-generator.