1000 MW汽轮发电机转子绕组匝间短路故障诊断与分析

Diagnosis and analysis of 1000 MW turbine generator rotor winding inter turn short-circuit fault

发电机转子绕组匝间短路故障由于发生次数多、故障诊断难度大、故障后果严重等原因,严重威胁电厂电气主设备的安全稳定运行。因此,如何准确诊断大型汽轮发电机转子绕组匝间短路故障就成了电力行业亟待解决的难题之一。文中首先介绍了转子匝间发生短路故障的原因、故障的分类和故障的分析诊断方法等内容,接着以一起刚投产的1 000 MW汽轮发电机转子绕组匝间发生短路故障的案例为基础,说明了转子匝间短路故障的诊断方法和过程。根据电气试验的结果和现场检查情况,确定转子线圈拐角处铜线打磨不充分是造成转子匝间发生短路故障的主要原因。

The inter-turn short-circuit fault of the generator rotor winding is seriously threatening the safe and stable operation of the electrical main equipment of the power plant due to the frequent occurrence, the difficulty of fault diagnosis and the serious consequences of the fault. Therefore, how to diagnose the fault of large turbo generator rotor winding inter-turn short circuit becomes one of the most difficult problems to be solved in power industry. In this paper, the causes of short-circuit faults in the rotor turn, the classification of faults and the analysis and diagnosis methods of faults are first introduced. Then, based on the case of short-circuit faults occurring in the rotor windings of the 1 000 MW turbine generators that have just been put into production. The diagnosis method and process of the inter-turn short circuit fault of the rotor are explained. According to the results of the electrical test and the on-site inspection, it is determined that the insufficient copper wire grinding at the corner of the rotor coil is the main cause of short-circuit faults between the rotor turns.