Research Of Influence Factors On Lightning Surges In 500kV Substation

Operation statistics show that the 500 k V substation accident caused by lightning intrusion is an important cause of large area power outages,which may cause serious economic losses and bad social impact.In the past,a large number of standards,reports,papers on the 500 k V substation lightning invasion of the calculation of the project evaluation.But previous research domestic and abroad puts forward a large amount of electrical geometry model,insulator flashover model,impulse tower ground resistance model of substation lightning invasion wave calculation model,the existence of lightning current for the first time,the follow-up of the situation.A variety of lightning protection measures are put forward and used at home and abroad,which is used to reduce the risk of lightning intrusion of substation,and the current lack of deep research on the lightning invasion wave of substation.In this paper,a detailed analysis compared before the proposed 11 electric geometry model,using MATLAB electric geometry model program with ATP-EMTP built 500 k V substations lightning intruded wave model,establishment of 500 k V substations lightning intruded wave risk assessment model.The electrical geometry model,lightning current,insulator flashover model three kinds of models of 500 k V substation lightning invasion wave risk assessment of effect,the lowered into the line tower grounding resistance,into the line of the tower height,increase the line lightning shield line or coupling ground wire of three kinds of lightning protection measures of 500 k V substation lightning invasion wave risk assessment of the effects.The results of the study show that:(1)different electrical geometry model,500 k V substation main equipment lightning invasion wave mean time between failures have significant difference,the necessary choice and local lightning activity and operating statistics are close to electrical geometric model for the evaluation,analysis;(2)lightning current amplitude distribution of median current and different insulation flashover model of 500 k V substation primary equipment MTBF(mean time between failure,MTBF)have significant impact;(3)segment tower grounding resistance is bigger,tower call said at higher altitudes,500 k V transformation power station main equipment lightning invasion wave MTBF is small.