Reducing power system model dimensions based on linearization for static analysis

Abstract

A reliable solution for determining the effect of a group of contingencies on a power system is to simulateall of them through load flow. It is impossible to simulate any detailed cases through a complete AC load flow solutionbecause of the high number of possible contingencies. For this reason, system dimension reduction methods, which arebased on an equivalent of one part of a system, are being used. In this paper we compare our previously proposednetwork equivalent method with the 2 well-known equivalent methods of Ward and Ward-PV in terms of solving speedand accuracy. The proposed network equivalent method is based on linearization. In this method, first the networkis divided into 3 areas: internal, boundary, and external. Next, the equations of the external and boundary areas arelinearized and the external area equations are removed. By doing so, the number of equations is decreased and the speedof load flow solutions is increased. The simulations are applied on 14-, 30-, 39-, and 57-bus IEEE systems. The resultsof simulations show the effectiveness of our proposed method.