Optimized grounding design for 220/110 kV substations using CYMGRD: A simulation-based approach for safe and cost-efficient energy infrastructure

Grounding systems play a very important role in ensuring the safety of individuals and equipment against electric shock hazards, and they contribute to the performance of equipment and protection systems during fault occurrences in high-voltage substations as well as in distribution systems. In the design of an electrical grounding system, the total ground resistance, the layout of ground rods, and their dimensions must first be determined. Moreover, the grounding system should be designed in accordance with international standards. The authors of this valuable study address the practical problem of designing a 220/110 kV substation grounding grid that is more secure and trustworthy. Employing CYMGRD software aligns with the IEEE 80 standard, considering important subterranean elements such as soil resistivity and seasonal moisture fluctuations. Future studies must, however, look at how it behaves in unforeseen circumstances, such as shifting faults and climate conditions, to completely guarantee its dependability. Ground potential rise is effectively set at 5734.72 V by a modeled grounding scheme with a grid resistance of 0.147 Ω, satisfying safety demands. Step and touch voltages are kept within safe bounds without needless complication by the design's careful coordination of mesh size and ground rod location. The simulation-validated suggested design provides a workable and practical solution for substation grounding. In this article, design solutions for single-phase-to-ground and double-phase-to-ground faults that may occur in a plant and can lead to problems such as increased ground potential and consequently dangerous touch and step voltages, are proposed in compliance with the IEEE 80 standard. These solutions aim to correct the grounding network and are structured in such a way that the layout of ground rods is optimized to keep touch and step voltages within permissible limits, thereby increasing the reliability of the grounding network.