【摘要】 同塔双回输电线路电气参数不对称会造成线路电流、电压不平衡,影响系统运行的经济性与可靠性。介绍了同塔双回输电线路电气不平衡度的分析指标与计算方法,搭建了输电线路仿真模型,研究了双回输电线路不平衡度的改善措施。研究结果表明:同塔双回输电线路采用鼓型杆塔和逆相序导线排列方式可以有效降低负序和零序不平衡度;减小回间距离可以明显降低负序不平衡度,但会使零序不平衡度略微增大;单个整循环换位应该采用逆相序反向换位方式,两个整循环换位应该采用l/6-l/6-l/3-l/6-l/6换位方式;电容器补偿可以显著降低负序不平衡度,而且随着线路长度的增加,改善程度逐渐增大。更多还原

【Abstract】 Asymmetric electric parameters of doublecircuit transmission lines will lead to unbalance of current and voltage, influencing the economy and reliability of the system operation. Analysis indices of electric unbalance and computation methods for the indices were introduced in this paper. A simulation model of transmission lines was constructed, and improvement measures for electric unbalance of double-circuit transmission lines were also researched. Analysis results show that drum-shaped tower and reverse phase sequence arrangement of conductors will lower zero sequence and negative sequence unbalance degree. Decreasing distance between the double-circuit transmission lines can obviously lower negative sequence unbalance degree, but slightly raise zero sequence unbalance degree. To minimize electric unbalance degree, conductors should be arranged in reverse phase sequence and transposed in reverse direction for one single cycle transposition. For two cycle transpositions, conductors should be transposed in the l/6-l/6-l/3-l/6-l/6 way. Capacitor compensation can significantly decrease negative sequence unbalance degree. With the increase of the length of line, the effect of capacitor compensation increases gradually.更多还原