Study on Earth Surface Potential and DC Current Distribution around DC Grounding Electrode

Zhi-chao Ren, Chun-yan Ye, Hai-yan Wang

1Planning &evaluation center, Sichuan Power Economic Research Institute, Chengdu, China 2Equipment condition assessment center, Sichuan Electric Power Research Institute, Chengdu, China.

DOI: 10.4236/epe.2013.54B152                

Abstract

DC magnetic biasing problem,caused by the DC grounding electrode, threatened the safe operation of AC power grid. In this paper, the characteristics of the soil stratification near DC grounding electrode was researched. The AC-DC interconnected large-scale system model under the monopole operation mode was established. The earth surface potential and DC current distribution in various stations under the different surface thickness was calculated. Some useful conclusions are drawn from the analyzed results.

Keywords

DC Grounding Electrode; Magnetic Biasing; Soil Stratification; Earth Surface Potential; DC Current Distribution

Conflicts of Interest

The authors declare no conflicts of interest.

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