水轮发电机励磁绕组匝间短路转子温度场计算

Calculation of Rotor Temperature Field for Inter-turn Short Circuit of Hydro-generator Excitation Winding

转子绕组匝间短路是水轮发电机中一种常见的故障,该故障会对转子磁极温度的分布产生影响。以三峡水轮发电机为例,基于传热学理论建立转子磁极三维计算模型,并采用有限元方法对温度场进行求解,得到在励磁绕组匝间短路情况下的磁极温度场。在此基础上,研究了匝间短路位置变化、短路匝数变化以及冷却风参数改变对磁极温度场的影响。通过计算分析得出磁极中部励磁绕组短路对磁极高温区域影响较大等有意义的结论。成果为之后匝间短路应力和短路恶化的研究奠定了基础,也为电机设计者以及相关研究工作提供了一定的参考。

Rotor winding inter-turn short circuit is a common fault of the hydro-generator,which affects temperature distribution of the rotor pole. This paper took the hydro-generator of the Three Gorges Hydropower Station as an example and established a three-dimensional calculation model of the rotor pole on the basis of the heat transfer theory. The finite element method was adopted to solve the temperature field,and then the magnetic pole temperature field was obtained in the case of rotor winding inter-turn short circuit. According to the calculation,this paper studied the influence of the changes of short-circuit position,the number of short circuits and cooling air parameters on the magnetic temperature field. The results showed that the short circuit of excitation winding in the middle of the magnetic pole had a significant effect on the high temperature area of the magnetic pole. This paper lays a foundation for the further study of short circuit stress and short circuit deterioration and provides reference for generator designers and related researches.