Comparative analysis of EMC methodologies applied on transients studies of impulsive grounding systems

This paper presents a review study on state of the art techniques used for electromagnetic transient studies on grounding systems. First, an introduction about the subject is presented, emphasizing the importance of grounding in population safety and equipments protection. Following, the Circuit Approach, Transmission Line Approach, Electromagnetic Field Approach and Hybrid Approach are reported. The most currently used numerical methodologies for electromagnetic compatibility (EMC) problems solution, as Finite Difference Time Domain Method (FDTD), Moments Method (MoM), Finite Element Method (FEM) and Transmission Line Modeling Methods (TLM) are also discussed with focus in its characteristics, advantages and disadvantages. Finally, simulation results using TLM are presented emphasizing the easiness of implementation of this method.

I. Introduction

Grounding systems are one of the resources capable of keeping the physical integrity of an installation in the event of a lightning discharge, being one of the elements that compose the EMC. In the occurrence of a disturbance, the power system must keep its normal operation conditions not allowing that sensible electric equipments perceive these interference signals. Grounding schemes are also important for population security [1]–[2]. These schemes are constituted by simple horizontal or vertical rods to large grounding meshes. Still, they are one of the lightning stroke protection systems of industrial plants.