1000kV/500kV同塔混压4回输电线路的防雷性能

在线路走廊比较紧张的东部地区,特高压电网考虑架设同塔混压多回输电线路,特高压同塔混压多回输电线路相比常规线路在防雷性能上有没有其自身的特点,这是目前期待解决的问题。针对这一问题,利用电磁暂态程序（PSCAD/EMTDC）和改进的电气几何模型（EGM）计算了1000 kV/500 kV同塔混压4回输电线路的反、绕击跳闸率,分析了避雷线保护角θs、1000 kV线路底层横担和500 kV线路顶层横担之间距离H及500 kV线路顶层横担宽度l对线路绕击跳闸率的影响,比较了1000 kV/500 kV同塔混压4回输电线路和其他电压等级同塔混压线路的防雷性能。结果表明,线路的反击跳闸率较低,但存在500 kV双回反击跳闸的可能性。线路的绕击跳闸率高于其他电压等级的同塔混压线路,1000 kV绕击跳闸率随着θs和H的增加而增大,随着l的增加而减小。500kV绕击跳闸率不受θs的影响,随着H的增加而先减小后增大,随着l的增加而增大。线路整体绕击跳闸率随着θs、H和l的增加而增大。为了减小线路的绕击跳闸率,可减小θs和H,在19.06～25.06 m范围内适当增加l。

Lightning Performance of Quadruple-circuit Transmission Line with Dual Voltage 1000 kV/500 kV on the Same Tower

Mixed-voltage multi-circuit transmission line on the same tower can be considered in UHV grid in eastern area where line corridor is tensional.Aiming at the problem whether there are any different characteristics in lightning performance between UHV mixed-voltage multi-circuit transmission lines on the same tower and conventional transmission lines,back flashover and shielding failure trip-out rate of quadruple-circuit transmission line with dual voltage 1000 kV/500 kV on the same tower were calculated with...