| Today, with the development of gas turbine combined cycle power which has many desired features such as high efficiency, energy saving, environmental protection and reliability, much attention has been paid to air-cooling turbo-generator because of its simple system, convenient start, operation and maintenance. Recently, the design, manufacture technology and technological level in air-cooling turbo-generator have been improved increasingly, so unit capacity is increasingly enlarged. However, because the cooling capability of air is rather less than that of hydrogen gas or water at the same volume of cooling medium, and wind friction loss is rather larger, so researching on temperature field and ventilation system in the stator plays an important part in guaranteeing high effective, reliable and secure operation.Aiming at present complicated state of coupled field study among electromagnetic field, flow field and temperature field during generator operating, a new method that temperature field of stator is caculated and analysed based on fluid field in order to compute temperature field accurately is developed in this paper. First, electromagnetic loss of air-cooling turbo-generator is calculated and analyzed according to electromagnetic theory in the electric machine and all parts losses of generator stator are also computed. Second, the stator model is built based on computational fluid dynamics theory , and control equations are solved by using finite volume method, so fluid velocity and fluid temperature of cooling gas in the stator ventilation duct are computed. Finally, based on above results, generator stator model of temperature field is built and caculated, then a 150MW air-cooling turbo-generator is taken as an example to calculate on 3D temperature field of stator according to coupled field theroy, theoretical approach together with experimental results derived from the 150MW air-cooling turbo-generator confirms the validity of the proposed method and gets some useful conclusions.
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