Sensitivity Based Network Contingency Ranking Using Newton Raphson Power Flow Method

In the area of power system planning and operation, contingency analysis plays an important role. In the present days, on-line security assessment is done by contingency ranking, with the help of various computer software, incorporating iterative method like Newton Raphson power flow for obtaining the magnitudes of different parameters. The motive of contingency ranking is to create a short list of potential contingencies quickly and rank them according to their severity in an accurate manner. In this paper sensitivity based wide performance index with respect to outage have been presented. The Newton-Raphson power flow results were used to construct two kinds of performance indices, namely the real power performance index and voltage performance index, which reflect the degree of severity of contingencies. Then full AC load flow was performed for each contingency case, to study the contingency effect. The effectiveness of the proposed method has been demonstrated by contingency screening and ranking on a standard 6-bus and IEEE 14-bus system. Keywords— Power system security, Contingency assessment, Newton Raphson power flow, Simplified performance index