考虑避雷线影响的同塔多回输电线路不平衡度衡量新方法

Measuring unbalance degree of multi-circuit transmission lines on same tower with consideration of lightning conductor

针对同塔多回输电线路的优化设计与运行,计算了考虑避雷线影响的同塔多回输电线路阻抗参数,提出了表征同塔多回输电线路不平衡物理本质的新衡量方法。基于PSCAD软件仿真计算了同塔6回输电线路的不平衡度,对比分析了不同线路长度、不同相序布置情况下避雷线连接方式对线路不平衡度的影响。结果表明,所提出的衡量方法具有实用性、便捷性,能够准确地反映线路不平衡特性,选择线路最优相序布置方式;避雷线的连接方式是线路零序不平衡度的主要影响因素。

For the optimal design and operation of multi-circuit transmission lines on same tower,their impedance parameters are calculated with the influences of lightning conductors considered and a method of measuring the line unbalance degree is proposed,which characterizes its physical nature. The unbalance degree of six-circuit transmission lines on same tower is simulated and calculated with PSCAD software and the influence of lightning conductor connection pattern on the line unbalance degree is analyzed for different line lengths and different phase sequence layouts. Results show that,being practical and convenient,the proposed method can precisely reflect the property of line unbalance and select the optimal phase sequence layouts;the lightning conductor connection pattern is the main influencing factor of line zero-sequence unbalance degree.