Identification of vulnerable transmission lines in power system switching operations

In modern times daily increase in load has resulted in transmission network being operated beyond its stability limit. This has considerable impact on power system operations, as it may lead to outage of transmission lines, which includes sudden switching out of lines and its consequent alteration of the structure of the transmission system. In this paper, line vulnerability is investigated through switching out of transmission lines in power system operation from the perspective of transmission line losses due to switching based on N-1 criterion. The mathematical relationship between the network parameters and the line losses is presented. The associated network losses for each line outaged are obtained and presented. PowerWorld Simulator is used as a simulation tool. From the results obtained, the lines which are more vulnerable within the network are identified when compared to the system steady state base case operation. The study uses the standard Institute of Electrical and Electronics Engineers (IEEE) 30-bus network as a test case.