线路开关单相重合闸期间雷击事故及电磁暂态仿真

Analysis on Lightning Stroke Accident in 220 kV Transmission Line During Single-Phase Reclosure of Line Breaker and Its Electromagnetic Transient Simulation

介绍了220 kV线路开关单相重合闸期间遭受雷击损坏经过。根据保护动作、故障录波、雷电参数、线路故障点和设备解体情况分析了事故原因,并建立了模型对变电设备可能遭受的雷电侵入波过电压进行了电磁暂态分析。研究认为:远区雷击、绝缘子闪络接地故障造成线路开关单相跳闸;单相重合闸期间远区小电流绕击产生的侵入波导致开关断口绝缘击穿。建议加快广东地区110 kV、220 kV敞开式变电站线路终端避雷器安装工作,防止多重雷击导致线路开关断口击穿事故。

The lightning strike caused damage process of line breaker in 220kV transmission line during the single-phase reclosure of the transmission line is presented. Based on the action protection, recorded fault waveform, lightning parameters, searching for faulty point and breakage condition of the line breaker, the cause of the accident is analyzed, and a model is built to perform electromagnetic transient analysis on the lightning incoming surge, which the power transformation equipments possibly suffer from. Research results show that the single-phase trip of line breaker is caused by flashover grounding of insulator due to lightning stroke occurred in far zone, during the single-phase reclosure the incoming surge caused by small current shielding failure in far zone leads to the breakdown of switch fracture insulation, and then the line breaker is broken. To prevent the breakdown of switch fractures due to successive lightning strokes, the installation of arrestors at the terminals of 110 kV and 220 kV transmission lines should be speeded up.