Panel Session on Data for Modeling System Transients Insulated Cables

The available EMTP-type programs have dedicated support routines (Cable Constants) for calculating an electric representation of cable systems in terms of a series impedance matrix Z and a shunt admittance matrix Y, based on cable data defined by geometry and material properties. Z and Y are then used as the basic input for the various cable models applied in time domain transient simulations. This paper describes necessary procedures for converting the available cable data into a new set of data which can be used as input for Cable Constants. In particular, the paper shows how to handle the semiconducting screens of single core coaxial type cables. In situations where the cable plays an important role in the transient simulation, the user should also consider obtaining a specimen of the cable in order to verify the geometrical data provided by the manufacturer. The recommendations in this paper are supported by field test results.