换流站滤波电抗器暂态过电压下绝缘水平分析及配置方法

Analysis and Configuration Method for Insulation Level of Filter Reactor in Converter Station under Transient Overvoltage

直流滤波电抗器是换流站关键设备,其绝缘配置对换流站稳定运行至关重要,一旦绝缘发生对地闪络,可能引发供电故障甚至直流线路闭锁等问题。开展直流换流站滤波电抗器绝缘水平分析及配置方法研究可以预警、消除绝缘隐患,提高线路运行稳定性。针对工程实际换流站案例,研究换流站滤波电抗器绝缘裕度分析方法,并开展仿真计算;分析得到关键风险点的过电压水平,并与绝缘水平对比分析,提出不同安全裕度下的工程实际处理方案。结果分析认为,在运换流站直流滤波电抗器绝缘关键风险点处的绝缘裕度低于50%时,应重点关注并采取治理措施,进而保证运行安全。

DC filter reactor is a key equipment in converter station,and its insulation configuration is crucial for the stable operation.Once the insulation flashover occurs to the ground,it may cause power supply faults or even DC line blocking issues.The research for insulation level analysis and configuration method of filter reactors in DC converter stations can provide early warning,eliminate insulation hazards,and improve the stability of line operation.Aiming at the actual cases of converter station,the analysis method for insulation margin of filter reactor in converter station is studied,and the simulation calculations are carried out.The overvoltage levels of key risk points are obtained through analysis,and are compared and verified with insulation levels,so the practical engineering treatment plans under different safety margins are proposed.The result analysis suggests that when the insulation margin at key risk points of DC filter reactor insulation in conversion station which is in operation is less than 50%,special attention should be paid and control measures should be taken to ensure the safe operation.