ABSTRACT
A global grounding system is defined as an “equivalent earthing system created by the interconnection of local earthing systems that ensures, by the proximity of the earthing systems, that there are no dangerous touch voltages”. The interconnection of grounding systems connects in parallel the ground-grids of substations forming part of the global grounding system, with the result of lowering the total ground-resistance of the system, and therefore also the ground potential rise at each substation. The interconnection would allow the division of the ground-fault current occurring at a substation among multiple ground-grids; the fault current therefore would be partially prevented from flowing into the earth surrounding the faulty substation. Global grounding systems may exist in city centers, and urban or industrial areas characterized by low- and high-voltage grounding systems, and where the geographic proximity of substations is likely.
