Risk Assessment of Grounding Hazards due to Step and Touch Potentials Near Transmission Line Structures

Excessive step and touch potentials near high voltage transmission line structures due to severe ground faults present a hazard to anyone in proximity to a structure when a fault occurs. This paper extends the probabilistic analysis of step and touch potentials near transmission line structures reported at the 1982 IEEE Summer Power Meeting [1] and presents a complete computerized methodology for assessing the overall effectiveness of grounding for any given network and right-of-way conditions. The paper also illustrates some applications of the method in the Ontario Hydro system.