高电压技术2011，Vol.37Issue(9)：2156-2162,7.
特高压交流试验示范工程线路操作冲击试验电压波前时间计算分析
Simulating Calculation and Analysis on Time-to-crest of Switching Impulse for Test on Chinese UHV AC Pilot Project
摘要
Abstract
For UHV AC transmission lines,the sizes of tower windows are related to the air clearance determined by switching overvoltage.According to the air clearance switching-impulse（SI） test results obtained by China and other countries,longer the time-to-crest of switching impulse wave shape is,higher the discharge voltage of the air clearance is.To reduce the size of transmission line tower windows and save project construction cost,it is important to determine the time-to-crests of SI for test.We derived a conversion formula between waveforms of SOVs on transmission line and time-to-crests of SI for test,calculated the equivalent time-to-crests of SI of UHV transmission lines with EMTP,and analyzed the relationship between the equivalent time-to-crests of SI and amplitude of SOVs.Moreover,we calculated the flashover rate of transmission line by both statistic method and simplified method.The results can meet the requirements of national standard.However,the coefficient of variation affects the flashover rate greatly,and coefficient of variation of the 50% flashover voltage increases with the longer of the time-to-crest,namely,flashover voltages under long-time-to-crest SI have larger dispersion than those under short-time-to-crest SI,so 1000μs SI for air clearance SI test with cat-head-tower and cup-tower of UHV AC pilot project is suitable for impulse test considering the safety and cost.关键词
特高压交流示范工程/操作过电压/波前时间/换算关系/空气间隙距离/变异系数Key words
UHV AC Pilot Project/switching overvoltage/time-to-crest/conversion formula/air clearance/coefficient of variation分类
信息技术与安全科学引用本文复制引用
何慧雯,谷定燮,周沛洪,修木洪,戴敏..特高压交流试验示范工程线路操作冲击试验电压波前时间计算分析[J].高电压技术,2011,37(9):2156-2162,7.基金项目
国家电网公司重大科研项目 （）
