This paper presents big-M (penalty) method for optimum time coordination of overcurrent (OC) relays. The method is based on the simplex algorithm which is used to find optimum solution of linear programming problem (LPP). The method introduces artificial variables in the objective function to get an initial basic feasible solution (IBFS). Artificial variables are removed using iterative process...

Directional overcurrent relays (DOCRs) are widely used to protect power systems. For optimal coordination of DOCRs, several techniques have been proposed to solve this problem. A common way of optimal coordination of DOCRs is using evolutionary algorithms such as genetic algorithm (GA). In this paper, a novel strategy for DOCRs coordination is proposed. In the proposed strategy, a new objective...

The inclusion of distributed energy resources (DER) in Microgrids (MGs) comes at the expense increased changes current direction and magnitude. In autonomous mode MG operation, penetration synchronous generators (DGs) induces lower short circuit than when operates grid-connected mode. Such behavior impacts overcurrent relays makes protection coordination difficult. This paper introduces a novel...

The overcurrent phenomena are a dangerous condition that can be occurred in the electrical system and equipment. of will cause short-circuited current flows through affect other distribution line. purpose this study is to investigate coordination relay different types network which radial system, ring interconnected during line ground fault occur at bus. generation directional flow damage neare...

This paper presents the implementation of Artificial Bees Colony (ABC) algorithm in solving Directional OverCurrent Relays (DOCRs) coordination problem for near-end faults occurring in fixed network topology. The coordination optimization of DOCRs is formulated as linear programming (LP) problem. The objective function is introduced to minimize the operating time of the associated relay which d...

This paper contains the application criteria and coordination process for a proposed overcurrent relay in a radial power system with feed from one or multiple sources. This relay uses independent functions to detect faults and to calculate the operation time. Also this relay uses a time element function that allows it to reduce the time relay operation, enhancing the backup protection. Some of ...

Computational intelligence method such as Nature Inspired Algorithms (NIA) or meta-heuristic algorithms based optimization methods known to be successful in coordination of directional overcurrent relay. It has also been reported that it outperformed the conventional approach. Due to its advantages, it has gained more popularity among the researchers. Some of the conventional optimization techn...