Tretiak O. Thermal condition of the stator winding bars of Turbogenerators with air cooling

The object of investigation is the processes of heat transfer in bars of Turbogenerators, heat release conditioned by circulating currents and ohmic resistance, limiting heat exchange conditions of bars with cooling air. Purpose is to improve the efficiency of Turbogenerators by a more detailed analysis of the thermal state of the current leading stator bars. Research methods are heat transfer theory and mathematical statistics, numerical methods for solving systems of algebraic and differential equations, the theory of physical experiment. Theoretical and practical results are mathematical model determining the geometry of bars, more accurate boundary conditions are universal and can be used to solve a fairly large range of important tasks related to the design of electrical machines. Novelty is in the first time the three-dimensional mathematical model of the thermal state of the overhang parts of the stator bars of Turbogenerator, which differs from the existing ones by more precise definition of heat, the conditions of heat exchange with the cooling air. The degree of implementation is the results are used at the SEP "Electrotyazhmash" in design of new and modernization of existing generators rated from 10 MW up to 500 MW. Area of application is thermodynamics, energetics.