Study on the Eddy Current Losses of Bus Bars of Large Hydro-Generators

摘要

The bus bars act as important parts in the large generator, which conduct the heavy armature current to the outside devices. Because of the skin effects and proximity effects, the distribution of eddy current becomes nonuniform. Some bus bars may be so hot as to damage insulating layers. In this paper, a numerical method based on harmonic finite element method is employed to study on the magnetic field of multiple bus bars. With the aim of verifying the effectiveness of the method, the eddy current losses of bus bars of a 300MW hydro-generator at Liujiaxia power station was calculated in detail. With comparing to the test results, some meaningful conclusions are obtained. The research work has meaningful significance for the cooling system design of large generators.