大型发电机转子匝间短路故障诊断及定位

Diagnosis and Positioning of Turn-to-turn Short Circuit Fault of Large Scale Generator Rotor

依据转子直流电阻和交流阻抗对早期发电机转子匝间短路故障进行定位仍不够准确。基于此,分析了一种匝间短路故障诊断及定位的方法,该方法首先对转子各线圈交流压降进行测量,并通过对比分析各线圈的压降确定故障点。以广东珠海金湾发电有限公司一台600 MW汽轮发电机组转子绕组单点匝间短路的故障为例,根据所提方法对该机组的转子进行现场试验并定位故障线圈,后再返厂查找并处理故障点。转子返厂拔出线圈后查找出的故障点与现场判断一致,表明该方法的可靠性及准确性,可为电厂降低了维修成本并缩短检修工期。

It is not accurate enough to locate early turn-to-turn short circuit fault of generator rotor according to direct current resistance and alternative current impedance of the rotor.Therefore,this paper analyzes a kind of diagnosis and positioning method for turn-to-turn short circuit fault which firstly measures alternative current voltage drop of each coil and then confirms the fault points by comparing and analyzing voltage drop.Taking turn-to-turn short circuit fault of single point of rotor of one 600 MW steam turbine generator in Guangzhou Zhuhai Jinwan power co.,ltd.as an example and according to the proposed method,field experiment was carried out on this unit and the fault coil was located,then the fault point was found and disposed after returning back to the plant.The fault point was the same as that determined on the scene after pulling out the coil which indicated that this method was reliable and accurate to reduce maintenance costs and shorten time limit for overhaul.