交直流并行输电线路地面混合电场的计算及试验研究

Calculation of Hybrid Electric Field Under the Parallel AC/DC Transmission Lines and Its Experimental Research

针对交直流并行输电线路下方地面混合电场的特性,对交直流电场的相互影响作了分析,并对单根交流导线和单根直流导线形成的混合电场进行了试验研究。采用了基于Deutcsh假设的计算方法,对试验模型的地面混合电场进行了理论数值计算,试验结果与理论计算的结果相吻合,验证了该算法的有效性。最后,计算了实际的特高压交直流并行输电线路的地面混合电场,并与忽略交直流电场相互影响的计算结果进行对比,得出了交流线路的屏蔽效应将使地面直流离子流电场强度减小等结论。

According to the characteristics of hybrid electric field under the parallel AC/DC transmission lines, the mutual influences between AC and DC electric field is analyzed and the experiment research is undertaken for the hybrid electric field formed by single phase AC and monopolar DC conductors. Using a calculation method based on the Deutcsh assumption, the ground-level hybrid electric field of the experimental reduced model is calculated. The calculation is in good agreement with the experiment results, thus the calculation method is demonstrated in validity. Moreover, the ground-level hybrid electric field of the parallel UHVAC and UHVDC transmission lines is calculated. The calculation results are compared with the corresponding calculation results when mutual influences between AC and DC electric field are neglected and the conclusion is obtained that the magnitude of ground-level DC ion flow field under AC line is reduced owing to an intensified AC line shielding effect resulted from the AC corona.