Optimized protection coordination of smart grids considering N-1 contingency based on reliability-oriented probability of various topologies

Abstract

The optimized protection system is critical in the design of microgrids (MGs) and smart grids (SGs). Different studies have tried to respond to MGs protection challenges, such as the coordination constraint violations due to changes in the system configuration. However, a few references have focused on all N-1 contingency-based configurations, besides the islanded and grid-connected modes. Moreover, in a few available studies considering N-1 contingency, the probability of different configurations has not been concerned. This article aims to fill the discussed research gap by proposing a new coordination optimization problem based on the reliability-oriented probability of various configurations and operation modes. Smart selecting the standard relay curve types (RCTs) to speed up the proposed protection scheme is used in this study. Also, developing a new hybrid optimization algorithm using the genetic algorithm (GA), particle swarm optimization (PSO), and linear programming (LP) is another essential contribution. The distribution network of the IEEE 14-bus test system is selected to examine the proposed protection scheme. It is illustrated that the introduced protection system, using the reliability-oriented probability of the configurations, is around 2.6% faster than the available schemes (with the same weighting coefficients for various configurations) without any selectivity constraint violation.