Reliability Comparison of Five 220 KV Substations in Pakistan Power System

In modern electrical power system, the reliability is considered to be an important factor in power system operation. The term reliability defines as the ability of power system to deliver an adequate supply of electrical energy to the consumers. Fault tree analysis and event tree analysis are the two methods used here for reliability analysis. To find the failure probability fault tree is used. To classify whether the system is safe or not event tree is used. The reliability of five 220kV National Transmission and Dispatch Company (NTDC) substations of Pakistan with respect to protection failures evaluates in this paper. The main method used in this study is Event Tree Analysis. Fault tree analysis helps to find the input for event tree