Equivalent Circuit Model of Soft Shield Defects in Coaxial Cables Using Numerical Modeling

This paper presents a three-dimensional modeling study to investigate the effects of one type of soft fault problem in electrical fault diagnosis, the impacts of partial degradation in the coaxial cable shielding or other shielded lines. At first, a time domain nodal discontinuous Galerkin method is used to solve Maxwell's equations and simulate reflectometry responses of soft faults. Then, the numerical simulation results for soft defects in cable shields are compared with experimental measurements for validation purposes. Finally, the shield defects that can arise on coaxial cables are modeled by an equivalent circuit and compared to illustrate their impacts on the electrical characteristic parameters as a function of their severity.