高压直流双回输电线路合成电场与离子流的计算

Calculation of Total Electric Field and Ionic Current Density of Double-Circuit HVDC Transmission Lines

高压直流双回输电线路在我国尚无设计与运行经验。为此,文章对双回直流线路电晕效应产生的离子流与综合电场强度进行了计算,分析了导线不同的布置方式以及线路间距、对地高度、导线分裂数、导线半径等结构参数对地表离子流和场强的影响。结果表明,两回线路上下排布方式的地表合成场强与离子流密度较小;在相同导线尺寸与同等架设高度下,合理排布的双回线路的地表场强与离子流远小于单回线路,且双回线间距越小地表场强与离子流越小;同塔双回线路的电磁环境要优于单回线路。

In China there are still not experiences in the design and operation of double-circuit HVDC transmission lines. For this reason, the authors calculate the total electric field and ionic current density caused by corona effect of double-circuit HVDC transmission lines, and analyze the impacts of different conductor configurations and stlucmral parameters such as conductor inter-spacing, line height to ground, number of sub-conductors and conductor radius, on ground ionic current density and field strength. Calculation results show that the ground total electric field strength and the ionic current density is smaller while the two transmission lines are configured vertically under the same conductor dimension and line height, the ground field strength of rationally configured double-circuit transmission lines is far less than that of single-circuit transmission line; the smaller is the double-circuit lines＇ vertical inter-spacing, the less are the ground field strength and ionic current; in addition, the electromagnetic environment transmission lines is superior transmission line. of double-circuit HVDC to that of single-circuit