METAP ߞA modular and expandable program for simulating power system transients

This paper describes the algorithms used by METAP - a transients program with a modular, expandable element-library. Each element is a computationally independent entity that can encapsulate an arbitrarily detailed model of a power system device - a synchronous machine or a transformer, for instance - together with a numerical procedure especially suited to the calculation of its responses. New elements can be added to the library whenever new models Or numerical procedures are needed. This modeling and computational flexibility is made possible by the use of unusual procedures for describing and solving networks. These procedures are described in some detail and their applicational aspects illustrated by means of an example.