Protection Coordination for Micro-Grids based on Multi-Objective Optimization Considering Simultaneous Uncertainty

The directional overcurrent relays (DOCRs) are the most important protection devices in micro-grids which are usually coordinated based on the fixed network topology. Due to the presence of the distributed generations (DGs), the setting of these relays is a nonlinear problem which should be solved using appropriate optimization algorithms. The network topology may alter because of uncertainties such as transient and permanent faults or the operator's mistake. The uncertainty increases the number of constraints that may be violated, and this issue complicates the solution algorithm. In this paper, a new objective function and a novel hybrid method are proposed based on multi-objective optimization considering simultaneous uncertainty by the genetic algorithm (GA) and network data analysis. The aim of the new proposed method is to coordinate the DOCRs in the presence of DGs incorporating uncertainty. The proposed approach is applied to the IEEE 14-bus system including distributed generation units. The results show the effectiveness of the presented method.