A Combined Fractional Order Proportional Integral Derivative Controller for Automatic Generation Control Integrated with Wind and Small Hydropower Plant Using Crow Search Algorithm

Automatic generation control (AGC) is essential for maintaining the frequency stability of power systems. However, designing an optimal controller for AGC remains a challenge. To overcome this deficiency, a novel two-degree-of-freedom-combined fractional order PID (2DOF-combined FOPID) controller is proposed and tested on two-area interconnected power systems consisting of reheat thermal and hydro units. The controller's performance is compared with conventional PID, FOPID, 2-DOF-PID, and 2DOF-FOPID controllers. The objective is to reduce the area control error. Optimal controller gain parameters are determined using the crow search algorithm (CSA) to minimize the integral time absolute error objective function. The dynamic behavior of the system is investigated in response to a 0.01 p.u. load disturbance in area-1. The designed controller's performance is also explored using wind integration and a CSA-optimized small hydropower plant. Results show that the 2DOF-combined FOPID controller outperforms the other controllers in terms of stability indices, including overshoot (Osh), undershoot (Ush), and settling time response (Ts) in the dynamic responses of the power system.