Simplified numerical-based method for calculation of DC ground electrode resistance in multi-layered earth.

摘要

The main focus of this thesis is to develop an efficient method for handling DC grounding problems involving earth non-homogeneity. A numerical technique has been employed using a commercial Finite Element Method (FEM) package called ANSYS 5.5. Due to the large scale of the problem domain a technique known as 'substructuring' has been used.; Classical analytical solutions were utilized to establish the accuracy of the numerical solutions. It is shown that an error of no worse than 10% in the estimation of the ground resistance can be guaranteed with only a few exceptions, which are pointed out in the thesis.; A technique for reducing a problem involving two-layered earth to a homogeneous earth is proposed. This procedure can be extended to cover for cases involving multi-layered earth. The effects of inclined earth layers have been considered and suggestions for handling such situations are proposed.