天生桥二级水电厂~#2变压器事故原因分析  

Analysis of Accident on ~#2 Transformer of Tianshenqiao 2^(nd) Hydroelectric Power Plant

作　　者：牛保红[1] 阳少军[1] 

机构地区：[1]中国南方电网超高压输电公司,广州510620

出　　处：《高电压技术》2007年第1期143-147,共5页High Voltage Engineering

摘　　要：为了查明天生桥二级水电厂发生的套管故障爆裂并引发变压器故障和事故扩大的原因,对套管进行了解体检查,判明事故原因为套管制造中的工艺缺陷,运行电压下产生局部放电,并最终导致绝缘击穿;在模拟分析计算了几种故障情况下变压器箱体内的压力分布后,确定压力释放装置设计不合理,导致故障情况下的箱体压力得不到有效释放和瓦斯继电器破裂,引发火灾,事故扩大。建议修复后的变压器加装压力释放装置,将该类型的瓷套管更换为干式套管,尽量避免采用三相油路相通的设计;对运行中的同类套管,加强电容量及介损的监测和分析。To find the cause of the oil-gas bushing failure which leads to the ^#2 transformer fault, the iron core and the winding of the phase of the transformer was confirmed and the porcelain of the oil gas bushing was exploded. The bushing was disassembled from the transformer and was dismantled on site, some little holes in insulation paper was found, which was caused by partial discharge at normal operation voltage and finally lead to insulation breakdown. To find the reasons that leads to fire and why the pressure relieve device didnot function correctly in this accident, which lead to the breakage of buchholz relay and fire occurred, the pressure distribution in tank at different accident and different positions was calculated and evaluated. It is confirmed that the pressure relieve device design of this transformer can not operate properly for this accident. It is advised to assemble pressure relieve device on all phases one by one and to replace the porcelain oil-gas bushing with dry-type bushing on the transformer. The design of the phase unit was not recommend for new product. For the bushing of this kind in operation, shorten monitoring cycle is recommended.

关 键 词：变压器 油—气套管 压力释放装置 故障 原因分析 

分 类 号：TM407[电气工程—电器]