Contingency Ranking and Selection using Static Security Performance Indices in Future Grids

Abstract

Contingency analysis is a mathematical tool for predicting equipment failure or the failure of a particular line and taking corrective action before the system enters an unstable region. The contingencies may be insertion or removal of one or more elements in an electrical network. These changes lead to situations where the power system no longer remains in the safe operating region. Corrective action should be taken as soon as possible; otherwise the system may enter an unstable region. Contingency ranking selection is an effective method of providing a power system security assessment. This report summarizes the research work in the field of contingency analysis and how to find various performance indicators and classify them according to their severity. Various software tools are available to perform the contingency analysis. Software such as ETAP, Neplan, PSCAD and power world simulator are helpful to carry out various analysis of a particular bus system. For a small to medium bus system these are very useful software. Although they can be used for larger number of bus systems, it makes the process tedious and unreliable. Hence to overcome this problem, soft computing techniques can be very useful. In this the algorithm used is the Ant Colony Optimization (ACO). This algorithm is implemented for the contingency analysis of IEEE 57 bus system using MATLAB software. The ranking is done based on the severity of power flow. It is analysed for the ranking of two different branches of bus system. The two different methods were compared and the effectiveness of the algorithm can be verified based on the output results.