1000kV交流紧凑型输电线路过电压与绝缘配合  

Overvoltage and Insulation Coordination of 1000kV AC Compact Transmission Line

作　　者：戴敏[1] 周沛洪[1] 娄颖[1] 何慧雯[1] 

机构地区：[1]国网电力科学研究院,武汉430074

出　　处：《高电压技术》2011年第8期1843-1849,共7页High Voltage Engineering

基　　金：国际科技合作项目(2008DFR60010)~~

摘　　要：特高压紧凑型线路输电工程的关键技术之一是限制过电压水平和合理选择线路绝缘水平。为此,基于两个500 kV区域大电网之间采用1000 kV紧凑型线路作为联络线的特高压系统,采用EMTP程序,重点研究了长度为100～500 km的紧凑型线路的工频和操作过电压,统计分析了线路合闸和单相重合闸相地和相间过电压的波前时间和相间过电压的电压分配系数α,以及它们与操作过电压幅值的关系。提出了避雷器额定电压可选828 kV,1ms波前时间和α=0.4系数可用于真型杆塔塔窗和档距中央的操作波间隙试验。紧凑型线路的绝缘配合表明,操作过电压对塔窗处的相地空气间隙大小起控制作用,偏严考虑,海拔1000 m地区的塔窗相地和相间操作波最小空气间隙可分别选为7.5 m和10.9 m,工频电压和操作过电压要求的档距中央的最小空气间隙可分别选为4.6 m和9.7 m。One of the key technologies of 1000 kV UHV Compact Transmission line project is to limit overvoltage and to reasonably select insulation level. We researched the power frequency and switching overvoltage of the 1000 kV UHV compact transmission line with line length from 100 km to 500 km by means of EMTP on the basis of a project of UHV AC compact joint transmission line between two 500 kV power network. The front time of overvolt- age of energizing unload line and single phase reclosing, and the a factor of phase-phase switching overvoltage are statistically analyzed, and the relationship of the front time and a factor to overvoltage amplitude is also analyzed. The 1ms front time of switching impulse and a= 0.4 parameters can be used to test air clearance of full scale line tower. The insulation coordination results indicate that the phase-ground air clearances of tower window are con- trolled by switching overvoltage, the rated voltage of arrester can select 828 kV, the minimum phase to ground and phase-phase air clearance of tower window at attitude 1000 m area can select 7.5 m and 10.9 m respectively by strict consideration, the minimum phase to phase air clearance required by power frequency operation voltage and switching overvoltage at middle of line span can select 4.6 m and 9.7 m accordingly at attitude 1000 m area.

关 键 词：1000 kV特高压紧凑型线路 过电压 波前时间 电压分配系数a 空气间隙 绝缘配合 

分 类 号：TM862[电气工程—高电压与绝缘技术]