The coordinated or selective power system can be considered as a sequence procedure among two protective devices installed in series and having certain features. The coordination of protective devices in protection system is a very substantial procedure to guarantee a strength and reliable power system. Directional overcurrent relays coordination is considered as an optimization problem. Due to the difficulties that face this problem especially in multi-loop networks; it is a complicated challenge taking into account the problem constraints. An overview of various metaheuristic-based optimization methodologies is presented to get a proper solution for the coordination problem between each relay pairs to guarantee satisfactory relay settings. In addition, offering various methods of relay coordination, a comparison between earlier works is also performed. It's expected that this study will be helpful for researchers interested in this field.

可以将协同或选择性电力系统视为串联安装并具有某些功能的两个保护装置之间的顺序过程。保护系统中保护设备的协调是非常重要的过程，可确保系统的强度和可靠性。方向性过电流继电器的协调被认为是一个优化问题。由于面临这个问题的困难，尤其是在多回路网络中；考虑到问题约束，这是一个复杂的挑战。概述了各种基于元启发式的优化方法，以针对每个继电器对之间的协调问题找到合适的解决方案，以确保令人满意的继电器设置。此外，提供了各种中继协调方法，还进行了早期作品之间的比较。预计这项研究将对对此领域感兴趣的研究人员有所帮助。