Analysis and Treatment of an Overheated Ablated Fault on the Pole Shoe Surface of a Large Tubular Hydro-Generator

Aimed at a new kind of overheated ablated fault on the pole shoe surface of a large tubular hydro-generator, based on the real site characteristics of the fault with combination of a physical field analysis, this paper reveals the occurrence mechanism of such faults from operational conditions, generator structure, material characteristics, and so on. On the basis of the results, the fault treatment and the generator improvement strategy are proposed. In addition, the treatment method has been applied to a faulty generator, and it successfully eliminating the fault. The research is of great significance for restraining the loss and heat of poles in large tubular hydro-generators as well as improving the safety and reliability of the operation of generators and power grids.

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