Evaluating the Effect of Protection system on Reliability of Automated Distribution System

Evaluating the impact of the protection sys- tem on the reliability of automatically controlled systems is a difficult task since it requires the modeling and integration of protection and system control sequences. Little or no pre- vious work has been done for such evaluation. This paper outlines the techniques that have been developed for predict- ing how protection failures affect the reliability of automated distribution systems. The failure modes of the protection sys- tems are simulated in the application studies described in the paper in order to show their effect on the system reliability. The paper discusses the results of the studies and demon- strates the importance of including protection in the reliabil- ity evaluation.