Effects of Non-Homogeneous Soils on Variation of Step and Touch Voltage Patterns in H.V. Substations Utilizing Finite Element Method

Document Type : Original Article

Authors

arak university of technology

Abstract

Grounding systems play a crucial role in ensuring the safety and reliability of high-voltage substations. However, variations in soil composition, particularly the presence of heterogeneous layers such as rock, can significantly impact grounding effectiveness. This study investigates the effects of non-homogeneous soil on step and touch voltage patterns using the Finite Element Method (FEM) in COMSOL Multiphysics. The simulation compares grounding performance in homogeneous and heterogeneous soils, analyzing electric potential and field distribution. A sensitivity analysis is conducted to assess the impact of varying soil resistivity on grounding safety. Additionally, different grounding techniques are compared to identify optimal solutions for mitigating potential hazards. The results indicate that heterogeneous soils increase step voltage and potential gradients, posing higher risks for personnel and equipment. The findings provide essential insights for improving grounding system designs in complex soil environments and expands new technical horizons to accurate investigation of new enhanced grounding grid structures.

Keywords


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Volume 2, Issue 1
March 2025
Pages 12-18
  • Receive Date: 04 March 2025
  • Revise Date: 17 March 2025
  • Accept Date: 18 March 2025
  • First Publish Date: 18 March 2025
  • Publish Date: 18 March 2025