Network equivalent for On-Line System

Abstract : E.K. Paulson, PAS 93, No. 6, November/December 1974, p.1741

This paper presents and discusses methods for including the influence of unobservable parts of interconnected system upon on-line contingency load-flow calculations for an observable study system, i.e. network equivalent s. Two different methods are described, one using conventional network reduction techniques and the other using linear approximation to the power flow equations. Result are given which have been obtained from a test system. Where simulations have been made using the entire interconnected system as well as using equivalents for major parts of the system.

Model Identification using Tie Line Power and Frequency Measurements

Abstract: M.W. Schwartz, G.L. Park and R.A. Schlueter, PAS 93 No. 6 November/Desember 1974, p.1733

The identification of dynamic model which related power and frequency deviation on a tie-line is investigated. The identification problem is posed and three identification algorithm are presented which produce model with different structural properties. Equivalent realizations are identified and used as dynamic equivalent and recursively in an iterative frequency prediction algorithm. Predictive models are also identified and used as frequency predictors is shown to be practical and provide information about the structure of interconnected power systems.