Power and earthing system modeling in natural coordinates

Abstract

A power system model in natural coordinates is developed for an efficient analysis of the currents and voltages in complex earthing systems caused by phase-to-earth faults. The approach suggested makes it possible to consider in a general and comparatively simple manner, the structural asymmetry of power and earthing system components and the multiple system failures. Phase coordinate models for transformer stations with auto- and separate multiple winding transformers are extended in a way to enable a proper interconnection with associated earth electrodes. Illustrative examples from practice are included.