Impact of Sensitivity Index Based Transmission Network Topology Control on Contingency Constraints

Transmission topology is constituted of enormous number of branches. To increase the reliability of the system, excess unused branches are built, that come into operation only in order to counter emergency outage situations. For different system conditions, there exist different types of optimal network configurations. Additional network management option to the operator is provided by Transmission Network Topology Control (TNTC), in case of system overload. TNTC brings about a significant reduction in losses along with violation relief and increased cost effectiveness of the entire power system. In this paper, the benefits of using TNTC to reduce post-contingency overloads has been analyzed and examined. Real time contingency analysis (RTCA) is used to identify the vulnerable contingency overloads. The candidate switching solution determination is done by using two proposed algorithms. Both the algorithms use sensitivity indexes. The two algorithms are based on transmission switching distribution index (TSDI) and flow transfer distribution index (FTDI) respectively. FTDI based TNTC method can be considered as an updated version of TSDI based TNTC method, in which network flow distribution is taken into consideration. Simulations have been performed to depict the individual effectiveness of both the approaches.