Optimal Overcurrent Relays Coordination in the Presence Multi TCSC on Power Systems Using BBO Algorithm

Optimal coordination of Inverse Definite Minimum Time (IDMT) direction overcurrent relays in the power systems in the presence of multiple Thyristor Controller Series Capacitor (TCSC) on inductive and capacitive operation mode on meshed power system is studied in this paper. The coordination problem is formulated as a non-linear constrained mono-objective optimization problem. The objective function of this optimization problem is the minimization of the operation time (T) of the associated relays in the systems, and the decision variables are: the time dial setting (TDS) and the pickup current setting (IP) of each relay. To solve this complex non linear optimization problem, a variant of evolutionary optimization techniques named Biogeography Based Optimization (BBO) is used. The proposed algorithm is validated on IEEE 14-bus transmission network test system considering various scenarios. The obtained results show a high efficiency of the proposed method to solve such complex optimization problem, in such a way the relays coordination is guaranteed for all simulation scenarios with minimum operating time. The results of new relay setting are compared to other optimization algorithms