Improving Grounding System for Oil Tanks Using Finite Element Method, Taking into Account the Frequency Dependence of Soil Parameters

Abstract

This work was devoted to the development of a simulation model of the grounding and lightning protection system for oil tanks, taking into account the frequency dependence of soil parameters, where we, based on the equations mentioned in previous studies, designed a grounding model for an oil tank taking into account the frequency dependence of soil parameters by using the finite elements method. and for different configurations, where it was observed that the grounding potential rise GPR was significantly reduced at high frequencies, especially in the case of high soil resistivity, the percentage of decrease in the grounding potential rise in the case of dry soil for the studied site 1266.65 Ω.m and for wet soil 596.27 Ω.m, respectively, 22.8% and 23.8%, respectively. and it was pointed out the necessity of conducting soil resistivity measurements before the tank construction process, and the need to use the network configuration of the oil tank grounding model in some cases where the soil resistivity is high and it is difficult to eliminate the effect of lightning current with the typical design mentioned in NFPA 780 for tank grounding.