Optimal coordination of over-current relay in a power distribution network using opposition based learning fractional order class topper optimization (OBL-FOCTO) algorithm

Abstract

For the appropriate service of the power system network, the protection system which is equipped with relays and circuit breakers must operate in proper and efficient manner. In the power protection system, relays act as the brain of the circuit breaker which sense the fault situation and send the command to trip the circuit breaker to isolate the faulty part for reliable operation of rest part of the power system network. The relay performance may be affected by the Plug Setting (PS) and Time Dial Setting (TDS) due to the complex distribution network. The performance of the relay operation can be improved by proper tuning of TDS and PS. Therefore, to optimize the PS and TDS and to improve the performance of relay operating time, an opposition based learning fractional order class topper optimization algorithm called (OBL-FOCTO) is presented. The proposed method is a modified version of classical Class Topper Optimization (CTO, in which an Opposition Based Learning (OBL) concept as well as Fractional Order (FO) updating concept is introduced to improve the explorative and exploitive properties. The exploitation, exploration and convergence behavior of OBL-FOCTO is validated using CEC-2020 benchmark functions. The performance of the proposed method is evaluated using six test systems like IEEE 3 Bus, IEEE 4 Bus and IEEE 30 Bus system respectively. The superiority of the proposed method is shown by comparing the obtained results with some other existing results obtained using some existing methods. The results of the presented method for the relay coordination problem shows that the total operating time of the relays is minimized ( taking 0.037 to 10.432 percent less operating time to perform the relay operation for different cases) while compared to existing results for all six test systems with maintaining coordinations between each relays and also fulfill other constraints. Further, a non-parametric statistical hypothesis test has been applied to all test systems of the simulation results to show their significance.