Voltage stability control of power systems using reduced network based optimisation

Abstract

This study presents optimisation based strategy to successfully control voltage stability of power systems using limited number of measurements. In a multi-area power system, Ward reduction based network is used to enhance the loadability margin of the overall system, based on measurements from the internal area only. Information regarding the recent changes in the external areas is considered in the reduced network through hybrid state estimator, to enhance the estimation accuracy of the system states. Predictor-corrector primal-dual interior point technique is used to optimise the loadability margin above a given critical margin. The voltages obtained for this optimised margin are used as target values for determining the actual control parameters, by means of Gauss-Newton optimisation. The proposed methods are successfully implemented on IEEE 30-bus and 118-bus test systems.