Optimized protection coordination of microgrids considering power quality-based voltage indices incorporating optimal sizing and placement of fault current limiters

Abstract

Several solutions, such as fault current limiters (FCLs), have been utilized to mitigate the challenges of smart grids and ADNs’ protection schemes. However, less attention has been paid to simultaneously optimizing the protection coordination and power quality (PQ) concerns, incorporating the FCLs. There is a research gap in the literature in developing a method for optimal placement and impedance value of FCLs to optimize the speed of the protection systems, voltage sag energy index, and voltage sag duration. This research aims to fill such a research gap by proposing a new multi-objective optimization problem based on the optimum placement and impedance value of FCL. The proposed method is examined by implementing the distribution network of the IEEE 30-bus test system. MATLAB and DIgSILENT are linked online to simulate the protection of the smart grid and PQ voltage-based analyses and find the best solutions by the genetic algorithm (GA). The comparative analyses infer that a 13.13% improvement in criteria, e.g., operating time of relays, voltage sag energy, and voltage sag duration, is achieved by optimal placement of FCLs, beside other decision variables.