550kV交流滤波器断路器灭弧室电场计算

交流滤波器小组断路器爆炸事故会给电网的安全稳定运行造成了极大的威胁,有必要通过对断路器的仿真计算来分析影响灭弧室内绝缘的因素以判断断路器的故障产生的原因。考虑到设备结构对称性,利用Solidworks软件建立了550 k V双断口瓷柱式断路器的单断口三维计算模型,包括动静弧触头、瓷套、SF6和空气包等,并采用有限元计算软件ANSYS开展三维静电场的仿真计算。通过对正常开断、瓷套壁有金属微粒、弧触头间有金属微粒、弧触头上有金属微粒和瓷套加宽等5种工况的计算,发现最大电场强度出现在断路器熄弧后7.5 ms时刻,弧触头上存在金属微粒将使最大场强值显著增加。适当提高灭弧室SF6气压并采取金属微粒吸附措施将有利于减少断路器内绝缘故障。

Electric Field Calculation on Arc-Extinguishing Chamber of 550 kV AC Filter Circuit Breaker

Faults happened on AC filter sub-bank circuit breakers (CB) would endanger the safe and stable operation of the power system. It's necessary to analyze the factors influencing the insulation of arc-extinguishing chamber by simulation and calculation of the CBs to identify the causes of CB faults. Considering structure symmetry, a 3D calculation model including moving/static contact, porcelain coat, SF6 gas and air package, is established by Solidworks software for one of the double breaks of 550 kV ceramic post breaker. Simulations of the 3D stactic electric field are carried out using ANSYS under five conditions: normal break, metal particles on porcelain, metal particles suspended between two arc contacts, metal particles on arc contact, and increasing inner diameter of porcelain. Results show that the maximum electric field happens 7.5 ms after arc is blown out, metal particles on arc contact will significantly increase the electric field intensity, CB insulation faults can be effectively reduced by raising the SF6 gas pressure properly and using metal particle absorption measures.