Protection Coordination Impact on Reliability of Distribution Systems With Distributed Energy Resources

Abstract

The effectiveness and reliability of a power distribution system hinge on the establishment and maintenance of efficient coordination between protective relays. Alongside the prevention of unwarranted overloads, inadequate coordination among relays may lead to an increased likelihood of revealing concealed failures within crucial components of the protection system, like Circuit Breakers. To assess the potential degradation of system reliability due to protection system malfunctions, this study proposes the utilization of a Markov model (MM) in combination with a Monte Carlo simulation (MCS) algorithm. Furthermore, the study also addresses the impact of the protective equipment mis-coordination on the concealed failure of protection systems. Subsequently, using a modified Canadian benchmark distribution system, the study computes the reliability indices of System Average Interruption Duration Index (SAIDI) and Expected Energy Not Supplied (EENS) for three distinct scenarios characterized by varying relay settings and protection coordination. The findings are subsequently presented to demonstrate how miscoordination of protection systems within the distribution network can affect the overall system reliability.