Compact models of nonuniform lines for earthing-system analysis

Simple compact models or overhead lines and metal sheathed/screened cables are suggested for the analysis of earth-fault currents and voltages. Models for lines and lines combined with cables are also developed. The models proposed make it possible to compose relatively simple expressions for calculating the earth-electrode voltages and currents of faulted substations, and for assessing the enhancements which can be achieved by using it nonuniform line or a combined line cable supply