GROUNDING RESISTANCE OF BURIED ELECTRODES IN MULTILAYER EARTH PREDICTED BY SIMPLE VOLTAGE MEASUREMENTS ALONG EARTH SURFACE - A THEORETICAL DISCUSSION

The earth is modeled as inhomogeneous conducting medium with multiple horizontal layers. For known layer conductivity and thickness, the voltage distribution and grounding resistance have been computed efficiently using an equivalent image method. In this paper, the reverse sequence is proposed, Without explicitly knowing the layer conductivities, thickness and number of layers, the equivalent images are determined by the voltage measurement results along the earth surface. Then these images are linearly translated to compute the underground voltage profiles and grounding resistance of buried electrodes. Such surface measurements are simple and inexpensive, and should give very accurate results based on the experience of applying these images in the microwave area.