Fractional calculus based controller design for load frequency control in two-area power systems

In this thesis, load frequency control of three different two-area power systems is realized. Two-area reheat thermal power system, two-area multi-source power system and non-linear two-area multi-source power system models are established and the behavior of four different controllers is observed for these models under two types of load changes. Proportional-integral-derivative (PID), tilt-integral-derivative (TID), tilt-integral-derivative with derivative filter (TIDF) and tilt-integral-derivative with fractional derivative filter (TIDFF) are the controllers designed and used in the thesis. Aiming to minimize the time-weighted absolute error (ITAE) metric, which is one of the error-based performance metrics, the controllers are designed by optimizing with the Equilibrium Optimization Algorithm. The objective function value, frequency change curves and tie line power curves obtained after the control of the power system models with the controller are examined and the settling time, undershoot and overshoot values of these curves under certain conditions are presented. The results obtained are presented in comparison with the studies in the literature. For most of the cases, the fractional calculus-based controllers, i.e. TID, TIDF and TIDFF, are found to outperform the performance of the classical PID controller.