Research On Transient Response Characteristic Analysis Of Invading Ligtning Wave And Protection Measures In UHV GIS Substation

Lightning invasion wave is the main reason of lightning fault in UHV Substation.Reasonable insulation coordination scheme and lightning invasion wave protection measures are the main means to reduce lightning fault in UHV Substation.Determining the insulation level of electrical equipment is the key problem of insulation coordination.The lightning impulse test is one of the important contents of insulation tolerance.The standard lightning waveform(1.2/50?s)is based on the measured data and corrected of the United States in 1929.Because different waveform parameters of lightning impulse have a quiet different influence on the breakdown features of the insulating medium,it is necessary to study the lightning invasion transient response characteristics of UHV substation by simulation.Therefore,the transient response characteristics of lightning intrusion in UHV substation are deeply studied by simulation,and the rationality of lightning impulse test waveform is demonstrated in this paper.Lightning arrester is the main measure of lightning overvoltage protection in Substation.At the beginning of the domestic UHV substation bus are equipped with lightning arrester,and there is an example that the 500 kV substation bus is not equipped with lightning arrester.It is very important to investigate the feasibility of bus is not equipped with lightning arrester in UHV substation based on the simulation.In summary,this paper mainly carried out the following work:First,this article combines a GIS substation and the engineering parameters of a domestic UHV double circuit AC project,the three parts "thunder source-inlet line-substation" as a whole,the simulation model based on ATP-EMTP program.Second,combined with the physical process of lightning surge voltage traveling wave in UHV substation,the influence of lightning stroke,line distance,voltage transformer and arrester on traveling wave characteristics is analyzed.Based on the existing research and simulation results,Under the actual voltage traveling wave parameters,discussed and analyzed the insulation tolerance level of the electrical equipment is lower and that of the standard lightning impulse waveform.Third,the maximum shielding failure current is calculated based on the improved electric geometry model when the tower under different ground inclination.Through the simulation research of lightning location,tower grounding resistance,the shielding failure of lightning current and voltage wave invasion effect on Lightning Overvoltage amplitude.Fourth: The over-voltage of shielding failure performance and back flashover of UHV substation of this study are calculated and analyzed in different single line single variable operation mode,different lightning arrester configuration scheme,the feasibility of installing bus without lightning arrester is studied.Fifth,based on the above research,combined with the existing protection strategies and the UHV project in this paper,some suggestions are given for the suppression of lightning surge overvoltage in UHV substation.In this paper,the lightning invasion wave suppression method of transformer substation is proposed by using the transient overvoltage monitoring to statistics the characteristic parameters and rules of real lightning Invasion Wave and correct the lightning impulse test waveform parameters.And gives the concrete scheme of the statistical waveform parameters.