Grounding System Equivalent Circuit: Non-Linear Modeling and Simulation Under Impulse Conditions

This paper investigates the behavior of grounding systems under impulse conditions using field experiments and PSpice simulations. An equivalent circuit model is developed, incorporating a non-linear resistor modeled using the ETABLE and GVALUE components in PSpice. This approach integrates experimental data to accurately represent soil ionization and capture the transient responses observed in field tests. The model also includes inductance and capacitance components to account for inductive and capacitive effects. Validated against experimental data from two sites with different soil resistivities, the model effectively reproduces the behavior of grounding systems. Simulations highlight the influence of inductance and capacitance on transient responses across different grounding configurations and soil resistivities. Although less dominant, capacitance is found to contribute to oscillations, even in lowresistivity soils. The study further examines how different remote earth configurations affect inductance and capacitance. This research provides valuable insights into grounding system dynamics, offering a practical method for determining inductance values and emphasizing the importance of considering both inductive and capacitive effects in grounding system design.