Analysis of Temperature Distribution in the Stator of Large Synchronous Machines Considering Heat Conduction and Heat Convection

The aim of this paper is the characterization of the convective heat transfer and its treatment in a 3-D model to calculate the heat transfer and related temperature distribution in large synchronous machines. The wall heat transfer coefficients in the ventilation ducts have been correlated to various design parameters by several computational fluid dynamics simulations and have been defined at the boundaries at the tooth and yoke iron in the numerical model. The losses have been determined in the copper bars and stator iron from electromagnetic calculations. The validation has been made for the stator temperatures with the established conjugate heat transfer method.