Modeling and analysis of URD cable systems

A method for modeling URD cables with explicit grounding representation is presented. The model accurately represents the skin effect in the cable conductor and shield, as well as in the soil and multiple grounds connected to the cable shield. The method is capable of representing insulated cables, semiconducting jackets, or bare concentric neutral cables. The accuracy of the model is validated by comparison with closed-form solutions of simple cable arrangements. The URD cable model has been integrated into EPRI's SMECC program, a program designed to analyze the ground potential rise of grounding structures. The overall model is also useful for analysis of effects due to loss of cable neutral. Typical results illustrate the effectiveness of URD cables in reducing ground potential rise and effects of loss of neutral. >