Intelligent method for protection coordination

This paper presents the application of artificial intelligence in protection coordination. It can substantially improve the coordination of protection relay operations. The relay settings and coordination requirements are formulated into a set of constraint equations and an objective function is developed to manage the relay settings by the time coordination method (TCM). Modified evolutionary programming (MEP) is employed to search for the optimum relay settings with maximum satisfaction of coordination constraints. The results show that the intelligent method for protection coordination can optimize the protection relay settings, reduce relay mis-coordinated operations, and increase supply reliability. The efficiency of TCM taking the fault current changes into consideration is also discussed in this paper.