CALCULATION OF ROTOR TEMPERATURE FIELD FOR HYDRO-GENERATOR AS WELL AS THE ANALYSIS ON RELEVANT FACTORS

With the development of modern electrical machine manufacturing, calculation veracity of electrical machine temperature field is more and more cared for. In this paper the mathematic model of the rotor temperature field for a hydro-generator is established, and hypothetical conditions of the solution region in the hydro-generator are presented. Losses density are calculated according to the electromagnetic field theory. SF320-48/12800 Hydro-generator is taken for example and temperature fields of a pole shoe and half an axial section in rotor is calculated in use of 3D Isoparemetric Element Method. The results meet the measured values very well. Numerical simulated method is applied to study the influence of the uneven surface coefficients of heat transfer in rotor抯 wind side and lee side on the temperature field in middle and end part of rotor. Also, the influence of the stray loss on the surface of pole on rotor temperature field is analyzed. Distribution rule of rotor temperature fields is obtained and this will provide dependable theory evidences for the design of cooling system and temperature inspection in department of generator running.