| Stator bar transposition technique of hydro-generator is one of the important issues inthe process of generator design. Designed optimal transposition way to reduce circulatingcurrent losses of stator winding bar very is effective, which can prevent overheating ofwinding and increase efficiency of hydro-generator. With the Large-scale capacitydevelopment of large hydro-generator, Corresponding heat load increases inevitably, thereis a serious influence of operational life and reliability of the generator directly. Therefore,the study of heating and cooling issues of hydro-generator become a top priority of the keyissues. In this dissertation, numerical calculation method for fluid and temperature field of180MW hydro-generator is mainly used, which settles the foundation for optimal designof the generator.Firstly, based on ventilation system structure and cooling way of180MWhydro-generator, three-dimensional solving model of stator radial ventilation ditch isestablished combined with fluid mechanics and heat transfer theory, the change of fluidvelocity in ventilation ditch is calculated, the distributions of velocity and flow of coolingair in the flow area are drawn.Secondly, circulating current loss of stator bar360°transposition,360°transpositionwith void and deficient360°transposition of are respectively calculated by the numericalmethod. Three-dimensional fluid-heat coupling solving model of hydro-generator forcalculation is built, the temperatures of the various stator parts are respectively analyzedand calculated for360°transposition,360°transposition with void,360°deficienttransposition of the generator stator windings, the impacts of various parts of generator’sstator structure temperature changes by these three transposition ways are get.Finally, the influence of inlet velocity on the fluid coupling field is researched. Bychanging inlet velocity of fluid and heat transfer coupling solving model, the influence of different inlet velocities on the generator cooling fluid and the temperature distribution ofvarious stator components are analyzed. |
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