摘要
本文介绍了一起35kV干式空心串联电抗器的短路故障情况,依据其结构特点及现场检查,初步判断线圈包封层间绝缘击穿。故障相解体发现包封层表面绝缘开裂有缝隙,揭开绝缘层后导线局部排列不紧密。对比正常相设备解体及试验结果,推断因玻璃丝布缠绕工艺及包封热胀冷缩造成包封内侧上端部外绝缘层开裂,遇多天雨水天气时潮气侵入包封,导致包封层绝缘性能下降,在AVC投切时发生击穿短路烧毁。据此提出匝间过电压试验、加装防雨罩、增加通风道清理项目、加强雨后包封温升测量等运检预防措施,防止类似故障再次发生。
A short circuit fault of 35 kV dry-type air-core series reactor is described in this paper.It is judged preliminarily by its structural characteristics and site inspection that insulation breakdown between the coil cladding layers is occurred.It is found by way of disassembling the faulty phase that there are cracks on the surface of the cladding layer and the partial layout of the wire is loose after removing the insulation layer.Compared with the disassembly and test results of normal phase equipment,it is inferred that the outer insulation layer at the upper end of the inner side of the encapsulation is cracked due to the winding process of glass fiber cloth and the thermal expansion and cold contraction of the encapsulation,and moisture invades the encapsulation in case of multiple-day rainy weather,which leads to the insulation performance degradation of the cladding layer,and the breakdown and short-circuit burning occurs during AVC switching.On this basis,such preventive measures as inter-turn over-voltage test,provision of rain proof cover,provision of ventilation duct cleaning items and strengthening of measurement of the temperature rise of the encapsulation after rain are proposed so to prevent of similar failures from recurring.
作者
张文明
李威
刘亚林
赵胜男
麻森
ZHANG Wenming;LI Wei;LIU Yalin;ZHAO Shengnan;MA Sen(State Grid Henan Electrical Power Corporation Maintenance Company,Zhengzhou 450000,China)
出处
《电力电容器与无功补偿》
2022年第5期57-63,共7页
Power Capacitor & Reactive Power Compensation
关键词
干式空心串联电抗器
绝缘击穿
短路
解体
开裂
dry-type air-core series reactor
insulation breakdown
short circuit
disassembly
crack
