An Analytical Model for Low Frequency Earthing System of the T-Pylon Transmission Tower

This paper proposes a low-frequency analytical model for the earthing system of the new T-Pylon transmission tower on the National Grid Transmission Network. Even though commercial software using either the Finite Element Method or Moments Method accurately simulates the earthing system, it is time-consuming and difficult to set up. The proposed model is both easy to use and accurate. The plate and driven rod configurations as well as their mutual effects are considered. To develop conventional analytical relations, the earthing system resistance is proposed as a function of the surface area between 16 m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>and 100 m<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>attached to a 16-pile system. Validation of the model is achieved through the use of a commercial earthing software. There is a 0.1 % difference between the results obtained from the proposed analytical model and numerical method. The model is utilized to evaluate step and touch voltage values as safety voltages on the power network.