With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the c...With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the construction investment. In this paper, the upstream finite element method was expanded to calculate the total electric field of same tower multi-circuit DC lines converted from double-circuit AC lines, and the validity of the algorithm was confirmed by experiments. Taking a DC line converted from a typical same tower 500 kV double-circuit AC transmission line as an example, the surface electric field and the ground total electric field in different pole conductor arrangement schemes were calculated and analyzed, and the critical height of pole conductors for DC lines in residential and non-residential area were determined. Then, the corridor width of DC and AC lines at critical height in residential and non-residential areas before and after AC-DC line transformation were compared. The results indicate that for DC lines converted from common 500 kV double-circuit AC lines, the ground total electric field can meet the requirements of corresponding standard with appropriate pole conductor arrangement schemes.展开更多
随着用电负荷急速增长,电网输送容量也亟需提升。在一定条件下,将已有交流线路改为直流线路,既可提高线路的输送容量,又可大幅减小建设投资,受到国内外关注。将上流有限元法进行拓展,应用于同塔双回交流线路改直流线路后同塔多回直流线...随着用电负荷急速增长,电网输送容量也亟需提升。在一定条件下,将已有交流线路改为直流线路,既可提高线路的输送容量,又可大幅减小建设投资,受到国内外关注。将上流有限元法进行拓展,应用于同塔双回交流线路改直流线路后同塔多回直流线路合成电场的计算,模拟试验线段试验结果验证计算方法的有效性。考虑典型500 k V同塔双回交流线路改为±500 k V直流线路,对不同导线型号和直流线路极导线不同排列方式下的导线表面场强和地面合成电场进行计算,并对其特性进行分析。在此基础上,确定改造后直流线路经过非居民区和居民区时的极导线最小高度和线路走廊宽度。结果表明,对于采用常用导线的500 k V同塔双回交流线路,改为±500 k V直流线路,选择适当的极导线排列方式,可以使地面合成电场满足标准要求。展开更多
文摘With rapid growth of power demand, transmission capacity is also in urgent need of upgrading. In some cases, converting existing AC transmission lines to DC lines can Improve the transmission capacity and reduce the construction investment. In this paper, the upstream finite element method was expanded to calculate the total electric field of same tower multi-circuit DC lines converted from double-circuit AC lines, and the validity of the algorithm was confirmed by experiments. Taking a DC line converted from a typical same tower 500 kV double-circuit AC transmission line as an example, the surface electric field and the ground total electric field in different pole conductor arrangement schemes were calculated and analyzed, and the critical height of pole conductors for DC lines in residential and non-residential area were determined. Then, the corridor width of DC and AC lines at critical height in residential and non-residential areas before and after AC-DC line transformation were compared. The results indicate that for DC lines converted from common 500 kV double-circuit AC lines, the ground total electric field can meet the requirements of corresponding standard with appropriate pole conductor arrangement schemes.
文摘随着用电负荷急速增长,电网输送容量也亟需提升。在一定条件下,将已有交流线路改为直流线路,既可提高线路的输送容量,又可大幅减小建设投资,受到国内外关注。将上流有限元法进行拓展,应用于同塔双回交流线路改直流线路后同塔多回直流线路合成电场的计算,模拟试验线段试验结果验证计算方法的有效性。考虑典型500 k V同塔双回交流线路改为±500 k V直流线路,对不同导线型号和直流线路极导线不同排列方式下的导线表面场强和地面合成电场进行计算,并对其特性进行分析。在此基础上,确定改造后直流线路经过非居民区和居民区时的极导线最小高度和线路走廊宽度。结果表明,对于采用常用导线的500 k V同塔双回交流线路,改为±500 k V直流线路,选择适当的极导线排列方式,可以使地面合成电场满足标准要求。
