An Analytical Method for Reduction of Frequency-Dependent Static and Dynamic Models of Electrical Systems

Abstract

Precise representation of the loads dependant on voltage and frequency in standard power form is normally used in modern static and dynamic models of electrical systems. In this paper the method of an elimination of such loads for the purpose of reduction of model’s dimension is offered. It is carried out through appropriate approximations of the load characteristics made simultaneously on voltage and frequency. Approximation of voltage leads to preservation of the linear form of the node equations for currents that allows applying the Jordan elimination. At the same time the specific mathematical operations are involved and performed over frequencydependent elements. As a result the number of nodes decreases and new frequency-dependent connections and loads are appeared in nodes of the reduced scheme. They promote exactly the same course of considered processes