Inductance Effects in Grounding and Bonding for Three-Phase AC Systems

Equipment grounding and bonding is important for electrical safety, in protecting against unwanted voltage and current, which can cause injury. The configurations of grounding and bonding conductors can be broken down into a number of typical arrangements. Inductance is an important factor in calculating the magnitude of ground fault currents. This paper examines and compares inductance formulas from the literature for a variety of grounding conductor configurations and return paths. It is found that the use of more accurate formulas than are normally used can present a significant improvement in the calculation of these inductances.