| UHV transmission line is high voltage,long distance transmission and large transmission capacity, no matter considering from the economic benefits or personal and property safety, There is very important significance to ensure the safe and stab operation of UHV transmission system. China is a country with many lightning, lightning is the biggest hidden dangers threatening to the safe operation of power grid, the lightning trip out is the main reason that caused the fault of transmission line. The transformer substation is the hub of the electric power system,the lightning accident may cause equipment damage or even outages, will cause incalculable loss, therefore, need to develop a lightning protection measures. According to the statistics over the years, the main reason is not the direct lightning caused lightning accident of substation, but the lightning invasion wave spreading from the line. On the other hand,UHV transmission project completion time is short, not much open operating data,especially lack of the detailed information when impulse voltage is applied. Therefore, lightning invasion wave analysis and protection of the UHV substation is necessary.In this paper, a 1000 kV GIS substation as the object of study.The substation and the inlet line as a unified network processing,the transmission of each module and each substation equivalent modeling.The main factors to impact the corona is the attenuation and distortion of the voltage wave,modeling with impulse corona module is more practical.According to the model of transient calculation results by EMTP-ATP electromagnetic transient simulation soft ware to build a simulation model of transformer substation.For UHV substation,refer to 500 k V substation lightning protection experience,according to the possible operation pattern of the substation,calculate the substation lightning invasion wave overvoltage and the maximum current flow through the arrester,from two angles: the actual situation, selection of calculation parameters,to discuss the lightning invasion wave overvoltage of multiple factors.At the same time, the paper discusses the configuration problem of arrester,line lightning arrester for lightning protection and the lightning invasion wave is discussed in detail.Combined with the lightning invasion wave overvoltage analysis results,research on configuration of surge arresters substation,developed for the protection of the substation.Finally, combined with the actual situation,putting forward some suggestions on the substation lightning invasion wave and the protection work. |
