With the expansion of electricity demand,transmission corridors are becoming scarce.AC and DC circuits running parallel to each other and sharing the same right-of-way or even the same tower become a possible option.D...With the expansion of electricity demand,transmission corridors are becoming scarce.AC and DC circuits running parallel to each other and sharing the same right-of-way or even the same tower become a possible option.Due to the existence of the adjacent line,space electromagnetic field and corona of another line may be changed.Different characteristics of two line types make the electromagnetic field of transmission corridors become more complex.Hybrid line is viewed as a whole.The calculation contains surface gradient,ground level electric field,radio interference and audible noise.Interaction between the two line types is considered.The calculation results show that the interaction is mainly concentrated in the inner corridor.In the role of DC electric field,AC electric field is no longer symmetrical and ground level electric field is significantly enhanced.Under the negative DC voltage,the positive corona of the waveform is significantly strengthened,and it is inhibited under the positive DC voltage.It is better to erect the positive DC line near AC line.展开更多
交直流同塔线路混合电场是决定导线对地高度和走廊宽度从而进行线路优化设计的重要因素。由于其地面横向分布是交流分量和直流分量共同作用的结果,因此其分布特性与两者的叠加和分布特点有着密切的联系。以两回330 k V、750 k V交流线...交直流同塔线路混合电场是决定导线对地高度和走廊宽度从而进行线路优化设计的重要因素。由于其地面横向分布是交流分量和直流分量共同作用的结果,因此其分布特性与两者的叠加和分布特点有着密切的联系。以两回330 k V、750 k V交流线路分别与单回?1100 k V直流线路同塔架设为例,分析了交流线路在不同布置方式与相序排列方式下地面混合电场的分布特性与规律,并据此计算了导线对地最小高度和走廊宽度。结果表明,根据混合电场交、直分量的横向衰减特性,从走廊中心向外,地面混合电场可分为交流分量占主导的"交流区",交、直流分量比例相当的"混合过渡区"以及直流分量占主导的"直流区",为保证地面交、直流分量"错峰"布置,两回交流线路应采用垂直或倒三角排布方式,此时导线最小对地高度按照交流线路单独运行时的情况设计即可。当交流为750 kV线路时,走廊宽度主要由交流电场控制;交流为330 kV线路时,走廊宽度则由交直流电场分量共同控制。最终推荐采用垂直排布的相序6和倒三角排布的相序4两种布置方式。展开更多
文摘With the expansion of electricity demand,transmission corridors are becoming scarce.AC and DC circuits running parallel to each other and sharing the same right-of-way or even the same tower become a possible option.Due to the existence of the adjacent line,space electromagnetic field and corona of another line may be changed.Different characteristics of two line types make the electromagnetic field of transmission corridors become more complex.Hybrid line is viewed as a whole.The calculation contains surface gradient,ground level electric field,radio interference and audible noise.Interaction between the two line types is considered.The calculation results show that the interaction is mainly concentrated in the inner corridor.In the role of DC electric field,AC electric field is no longer symmetrical and ground level electric field is significantly enhanced.Under the negative DC voltage,the positive corona of the waveform is significantly strengthened,and it is inhibited under the positive DC voltage.It is better to erect the positive DC line near AC line.
文摘交直流同塔线路混合电场是决定导线对地高度和走廊宽度从而进行线路优化设计的重要因素。由于其地面横向分布是交流分量和直流分量共同作用的结果,因此其分布特性与两者的叠加和分布特点有着密切的联系。以两回330 k V、750 k V交流线路分别与单回?1100 k V直流线路同塔架设为例,分析了交流线路在不同布置方式与相序排列方式下地面混合电场的分布特性与规律,并据此计算了导线对地最小高度和走廊宽度。结果表明,根据混合电场交、直分量的横向衰减特性,从走廊中心向外,地面混合电场可分为交流分量占主导的"交流区",交、直流分量比例相当的"混合过渡区"以及直流分量占主导的"直流区",为保证地面交、直流分量"错峰"布置,两回交流线路应采用垂直或倒三角排布方式,此时导线最小对地高度按照交流线路单独运行时的情况设计即可。当交流为750 kV线路时,走廊宽度主要由交流电场控制;交流为330 kV线路时,走廊宽度则由交直流电场分量共同控制。最终推荐采用垂直排布的相序6和倒三角排布的相序4两种布置方式。
