New Integral Formulas for the Elements of the Transient Ground Resistance Matrix of Multiconductor Lines

This paper proposes new formulas for the calculation of the transient ground resistance matrix elements based on the analytical solution of the inverse Laplace transform of the Sunde's logarithmic equation. The new formulas solve the computational issues in the representation of the transition between early time and late time response of the line that arises when adopting the expressions already available in the literature. The formulas are adopted for the calculation of the per-unit length voltage drop due to the transient ground resistance in a multiconductor overhead line and the results match those provided by the numerical inverse Fourier transform of Sunde's logarithmic equation.