STOCHASTIC ASSESSMENT `OF UNBALANCED VOLTAGE SAGS IN LARGE SYSTEM

Abstract

Most of the equipments used in modern automated industrial processes are sensitive to voltage sags. Voltage sags causes malfunctioning or failure of the sensitive equipments, which in turn leads to interruption of work with significant associated cost. Stochastic assessment of voltage sags is needed to find out whether a piece of equipment is compatible with the supply. In this work, voltage sags produced by unbalanced short circuits are calculated by means of new analytical method. The analytical method is demonstrated for an IEEE 24-bus Reliability Test System (RTS) in MATLAB7.0.1 platform. Three sensitive loads are considered in the network and financial losses associated with both balanced and unbalanced voltage sags were calculated using the results obtained from the analytical method.