EMP coupling to buried cables in the frequency-dependent soil

Buried cables are widely used in power systems. It is an important research on electromagnetic pulse (EMP) coupling on buried cables. In this paper, based on Agrawal model of transmission line (TL) equations and the finite-difference time domain (FDTD) method, the coupling problem of buried cables is studied. By using Vector-Fitting method, we represent soil impedance and admittance by a rational function approximation to form a convolution calculation. The impact of the frequency-dependent electrical parameters of soil on EMP coupling on underground cables is analyzed.