220kV变电站接地散流事故研究

Research on Grounding Scattering Accident of 220kV Substation

针对某变电站雷击导致绝缘子炸裂事故进行分析和研究,通过现场勘查分析,事故原因主要是由于避雷针接地问题导致。提出增设均压环、避雷针接地体进行冲击优化以及避雷针接地体与主接地网进行连接等措施,同时采用实验室高压试验和ATP仿真软件分别对均压环均压效果和连接主接地网降低残余过电压进行验证。结果表明,均压环能够有效的改善绝缘子串的电压分布,避雷针接地与主接地网连接很大程度上降低避雷针残余过电压。降低变电站雷击事故的发生,提高电力系统的供电可靠性。

The authoer analyzes and studies the insulator bursting accident caused by lightning strike in a substation.Through site investigation and analysis,the accident is mainly caused by the lightning rod grounding problem.It is proposed to add grading ring and lightning rod grounding body to optimize the impact and connect the lightning rod grounding body to the main grounding grid.At the same time,the laboratory high voltage test and ATP simulation software are used to verify the effect of the grading ring and to connect the main grounding grid to reduce residual overvoltage.Overvoltage is verified.As a result,the voltage grading ring can effectively improve the voltage distribution of the insulator string,and the connection of the lightning rod to the main grounding grid largely reduces the residual overvoltage of the lightning rod.Reduce the occurrence of lightning strikes in substations and improve the reliability of power supply in power systems.