An interior point method based protection coordination scheme for directional overcurrent relays in meshed networks

•Proposes a new objective function for improved protection coordination schemes.•Proposes interior point method based two algorithms for obtaining optimum solution.•Considers three distinct characteristic curves of directional overcurrent relays.•Comparison of the new objective function with the conventional objective functions.•Comparison of the proposed optimization algorithms with metaheuristic optimizers.

In this work, interior point method based protection coordination schemes are presented for coordinating directional overcurrent relays. Also, for minimizing the operating times of primary and backup relays simultaneously, a new objective function (NOF) is developed. The effectiveness of the proposed solution methods and the developed objective function has been investigated on two test systems (one small and one large). The suitability of the proposed method for coordination of directional overcurrent relays in meshed networks has been established by comparing its performance with that obtained by genetic algorithm, differential evolution and two hybrid algorithms for the developed objective function. Also, the superiority of the develop objective function has also been established by comparing the protection coordination results obtained by using NOF with those obtained by the other objective functions reported in the literature.