Grounding Grid Analysis: Historical Background and Classification of Methods

Abstract

This paper presents a review of the most important methods available for the grounding grid analysis. This includes numerical methods intended for the grounding grid direct current, time-harmonic current and transient current energization. Emphasis is given to the numerical methods involving transient grounding grid analysis. Available numerical methods are reviewed according to the implemented soil model, e.g. homogenous soil, horizontally and vertically stratified multilayer soil as well as exceptionally heterogeneous soil. In that regard, various possible treatments of the boundary between soil layers are discussed. Here, image methods feature prominently in a solution to this problem. Whence, several possible image methods are reviewed. Additionally, numerical methods are reviewed according to the theoretical background approach. Here, one can make a clear distinction between circuit approach, which might include a transmission line approach, and electromagnetic theory approach. Numerical methods for the transient analysis of grounding grids are also reviewed in regard to the domain of the solution. Therefore, they could be regarded as time domain and frequency domain methods. Fast Fourier transform algorithm is seen as a conventional way of crossing between frequency and time domains. Major advantages and disadvantages of both approaches are pointed out as well.

Petar Sarajčev

Full Professor | Department of Power Grids and Substations

Slavko Vujević

Professor Emeritus

An expert in electrical engineering, particularly known for his contributions to numerical modeling of electromagnetic phenomena, lightning protection, and grounding. Throughout his career, he was a key member of the Faculty of Electrical Engineering, Mechanical Engineering, and Naval Architecture in Split, where he taught, mentored students, and actively participated in scientific research and international professional organizations.