A magnetic detecting and evaluation method of substation’s grounding grids with break and corrosion

Abstract

The grounding grid buried in the earth will become a hidden danger to the safety of substations due to some faults of breaks or thinner conductors in corrosion. A novel method to get accurate status of grounding grid was proposed based on measuring magnetic induction intensity. The basic structure of grounding grid without working drawing was concluded, and the positions and the status of faults were diagnosed by this method. The completed detecting system, including hardware device of data measurement, diagnosis, and analysis software, was introduced concisely. The results of simulations and applications show that this method is simple and effective in the practical engineering.

Key words： grounding grid; fault status; magnetic induction intensity; diagnosis

Acknowledgements

This work was supported in part by the Scientific Research Foundation of Doctor Degree in North China Electric Power University (200912008).

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