水轮发电机定子线棒不同防晕结构的泄漏电流研究

本文针对两种防晕结构,即半截防晕和全防晕结构,通过有限元方法,对大型水轮发电机线棒端部的泄漏电流进行了理论分析,使用场路结合方法对单相泄漏电流计算方法进行了推导和验证,并进一步分析了直流和交流作用下两种防晕结构的具体差别。结果表明:直流电压下两种防晕结构的泄漏电流产生机理存在很大不同,电位和场强分布也有很大差别;交流电压下两种防晕结构的电位和场强分布基本一致;全防晕结构下较大的泄漏电流并不会影响水轮发电机绕组的相关交流试验和正常运行。

Research on Leakage Current of Hydro-generator Stator Bars with Different Anti-corona Structures

The leakage current of large hydro-generator stator bar end is analyzed by the finite element method according to the two anti-corona structure,half anti-corona structure and full anti-corona structure.The calculation method of single-phase leakage current is inferred and verified by field-circuit coupled method,and further analysis of the specific differences of the two anti-corona structure under DC and AC conditions has been completed.The results showed that the mechanism of leakage current,distribution of voltage and field intensity on two anti-corona structure differs a lot under DC,while under AC condition,the field strength and the voltage are the same basically.The large leakage current of the hydro-generator windings with full anti-corona structure will not affect relevant test and normal operation.