A hybrid grey wolf optimisation and pattern search algorithm for automatic generation control of multi-area interconnected power systems

Abstract

A hybrid grey wolf optimisation-pattern search (hGWO-PS) algorithm has been proposed to optimise the parameters of two degree of freedom-proportional integral derivative (2DOF-PID) controllers in multi-area power systems for automatic generation control. The integral of time multiplied by absolute error (ITAE) has been considered as an objective function in the present work. Firstly, this algorithm has been applied to a two-area non-reheat thermal power system; secondly, the analysis of ITAE, dynamic responses and robustness of the same has also been carried out. The dynamic behaviour of the system optimised by the proposed approach hardly alters with the broad changes in the load and system parameters within the range [−50%, +50%]. The proposed algorithm has also been applied extensively to a three-area hydro-thermal power system with appropriate generation rate constraints (GRC). The simulation results show that the proposed algorithm performs better when compared with recently published approaches in terms of less ITAE value, settling time, overshoot and faster system ability to return at zero frequency and tie line power deviations.