Automated Settings of Overcurrent Relays Considering Transformer Phase Shift and Distributed Generators Using Gorilla Troops Optimizer

Abstract

The relative protective devices are cascaded in a proper sequence with a proper min/max coordination time margin (CTM) to minimize the outage area of the network in case of fault condition. This manuscript addresses a new methodology based on the gorilla troops optimizer (GTO) to produce the best automated settings for overcurrent relays. In the GTO, the exploration and exploitation phases are realized using five methodologies. Three of them are used in the exploration phase and the other two in the exploitation phase. In the exploration phase, all gorillas are considered as candidate solutions and the best one is considered as the silverback gorilla. Then again, the exploitation phase comprises two steps: (i) the first one is the follow of silverback gorilla, and (ii) the second one is the competition for adult females. The latter mentioned offers an added advantage to the GTO framework to move forward steadily to global minima and to avoid trapping into local minima. Two test cases under numerous scenarios are demonstrated comprising an isolated real distribution network with distributed generations for the Agiba Petroleum company which is in the Western Desert of Egypt. The relay coordination problem is adapted as an optimization problem subject to a set of predefined constraints which is solved using the GTO including fixed and varied inverse IEC curves, in which the practical constraints including transformer phase shift and other scenarios for min/max fault conditions are dealt with. In due course, this current effort aims at proving the best strategy for achieving the smoothest coordination of overcurrent relays (OCRs), with the least obtained value of CTMs for the studied cases being established via the automated relay settings. At last, it can be pointed out that the GTO successfully dealt with this problem and was able to produce competitive answers compared to other competitors.

Keywords

• optimal overcurrent relay coordination
• smooth coordination
• transformer phase shift
• gorilla troops algorithm
• optimization methods