一起变压器套管底部软连接螺栓松动导致的过热缺陷分析  

Analysis of Overheating Defect Caused by Loose Connection of Transformer Bushing Bolt

作　　者：刘钊 杨彬 刘小琰 王佼 田小龙 LIU Zhao;YANG Bin;LIU Xiaoyan;WANG Jiao;TIAN Xiaolong(State Grid Hebei Electric Power Corporation Baoding Power Supply Branch,Hebei Baoding 071000,China)

机构地区：[1]国网河北省电力有限公司保定供电分公司,河北保定71000

出　　处：《农村电气化》2022年第11期33-35,共3页Rural Electrification

摘　　要：介绍了一起35 kV变压器因为低压侧套管底部软连接螺栓松动导致的过热缺陷。通过对故障变压器油色谱三比值法分析初步判定为高温过热型缺陷,再通过“四比值法”辅助分析进一步判断为绕组过热缺陷,然后有针对性地对变压器高、低压侧绕组开展停电高压试验,最终发现低压侧直流电阻测试横比超标,解体检查发现,是因为低压套管底部软连接螺栓松动导致的缺陷,并提出了防范措施。This paper introduces the overheating defect of a 35 kV transformer caused by the loosening of the soft connecting bolt at the bottom of the bushing at the low-voltage side. Through the analysis of the three ratio method of chromatogram of the fault transformer oil, it is preliminarily determined that the fault is of high temperature and overheating type. The winding overheating defect is further judged by the auxiliary analysis of "four ratio method". Then conduct power failure high-voltage test on windings at high and low voltage sides of the transformer. Finally, it was found that the DC/T ratio at the low voltage side exceeded the standard. Through disassembly inspection, it was found that the soft connecting bolts at the bottom of the low voltage bushing were loose. The preventive measures are put forward.

关 键 词：油色谱 流电阻 三比值法 四比值法 

分 类 号：TM421[电气工程—电器]