500kV GIS升压站主变合闸过电压影响因素分析

Analysis of Influencing Factors of Main Transformer Closing Overvoltage in 500kV GIS Booster Station

气体绝缘组合开关(GIS)在操作过程中会形成快速暂态过电压,影响与之相连的一次设备尤其是变压器的安全运行。为对GIS升压站主变合闸过电压进行量化,采用电磁暂态分析软件ATP-EMTP建立分布参数模型,对GIS升压站设备投运情况、出线数量、变压器与GIS母线连接管道的长度、避雷器与高压绕组距离对主变合闸过电压的影响进行仿真计算,得出了主变合闸过电压的特点。分析认为GIS操作时波的折反射是导致合闸过电压升高的主要原因,对于结构复杂的GIS升压站应开展过电压评估。

Gas insulated switchgear (GIS) will form a fast transient overvoltage during its operation,which affect the safe operation of the primary equipment connected to it,especially the transformer.In order to quantify the switching overvoltage of main transformer in GIS booster station,a distributed parameter model is established by using electromagnetic transient analysis software ATP-EMTP.The effects of equipment operation,number of outgoing lines,length of connecting pipeline between transformer and GIS bus,distance between lightning arrester and high voltage winding on switching overvoltage of main transformer are simulated and calculated,and the characteristics of switching overvoltage of main transformer are obtained.The analysis believes that the refraction of wave during GIS operation is the main reason for the increase of switching overvoltage,and overvoltage assessment should be carried out for GIS booster station with complex structure.