摘要
针对四川省洪沟、龙王等500kV变电站连续发生的并联电容器爆炸事故,计算分析了由于电容器组内部元件击穿而引起的过电压分布情况。对事故电容器的绝缘进行解剖后发现,严重的老化现象可以充分证明内部局部元件上的过电压是影响电容器绝缘性能的重要因素。最后,为确保并联电容器的可靠运行,通过计算35kV、6并7串结构的无功补偿电容器在运行中存在的不平衡电流,对双Y中性点的不平衡保护电流整定值进行了修正。
In order to make it clear for explosion accidents of parallel capacitors occurred in 500kV substations in Sichuan power network one after another, the authors calculate and analyze the distribution of over＇voltage caused by breakdown of elements within the capacitor bank. Dissecting the insulation of faulty capacitors, severe ageing of insulation is discovered; this phenomenon proves that the overvoltage on partial element should be the main factor influencing the insulating performance of capacitors. To ensure the reliable operation of parallel capacitors the setting value of unbalanced current protection at the neutral point of double star connection is modified by the calculated value of unbalanced current of 35kV capacitor bank in which there are six parallel groups of capacitors and in each group seven capacitors are connected in series.
出处
《电网技术》
EI
CSCD
北大核心
2005年第15期56-60,共5页
Power System Technology
基金
国家自然科学基金资助项目(10476022)
四川省青年科技基金资助项目(460)~~
关键词
并联电容器
过电压及其防护
绝缘击穿
不平衡电流
电力系统
Parallel capacitors
Over-voltage protection
Insulation breakdown
Unbalanced current
Power system
