Abstract:

In order to get the reality buried depth of conductors of substation’grounding grids，an exciting current of a definite frequency is injected directly into grounding grid by two ground lead wires. Then，the surface magnetic induction intensities of different places are measured based on the electromagnetic induction theory. We can obtain the practical buried depth of grounding grids by information of the magnetic fields and the place of measuring point places. The feasibility of the testing method is analyzed and the injecting apparatus are designed and developed.The correctness of the method is verified by laboratory experiments and field tests in substation. The results of theory analysis and measuring show that the technology method is operated easily and the measuring results are accurate and reliable. It can be used in the engineering practice of transport inspection of grounding grids. It shows that the theory of physics and circuit can be used to engineering technology.

Key words: grounding grids, conductors, buried depth, testing