Impact of supply restoration procedures on the reliability performance of power distribution systems

The purpose of this paper is to describe an efficient computational methodology that models supply restoration procedures, which are available in power distribution systems, and calculates their impact on the reliability performance of system load-points. This methodology recognizes various practical operating features of the distribution systems under consideration and deduces the switching operations that are available to be executed, following the occurrence of a failure event. A set of five probabilistic indices is also obtained for each affected load-point taking into account the component reliability parameters and the system operational and maintenance practices being applied. The unavailability indices of the system standby components are calculated separately and their effect on the system reliability performance is established. Finally, the analysis of a typical 150 kV/20 kV system based on a real Greek urban distribution system is included.