Computation Method for Transients in Underground Cables With Lossy Earth Return Path

In this paper, a detailed method for computing the transient voltage distribution in underground cables is described. The proposed model is based on RLCG lumped frequency-dependent parameters for time-domain analysis. The Numerical Laplace Transform technique in s-complex plane is used. The method is proposed for underground cable systems working at high frequencies (HFs). The real lossy earth return path is computed by means of the novel Machado´s technique successfully applied for transients for first time. Numerical results confirm very good agreement with reference solutions taken from the literature. The proposed numerical technique is specially recommended for computing very fast transients as a better alternative than those available in commercial packages.