Teaching-learning optimizer-based FO-PID for load frequency control of interlinked power systems

Designing an effective, robust controller is vital for regulating system frequency corresponding to the load demand variations in a traditional interlinked power system. Hence, load frequency control plays a critical role in countering load disturbances and minimizing unscheduled power flow between interlinked areas. This paper proposes a novel teaching-learning optimization (TLO) based dual-loop load frequency control approach aided by fractional-order proportional-integral-derivative controller (FO-PID). The inner control loop of the presented method employs internal model control and model approximation. On the other hand, the external loop uses a TLO-tuned FO-PID controller to improve the outcomes of the proposed approach. The proposed method is validated using a 1-area multi-stage reheat hydrothermal power system (RHTPS), 2-area reheat thermal power system (RTPS), and 2-area multi-stage RHTPS. The robustness of the proposed method is demonstrated by executing sensitivity analysis. It is established from the simulation results that the proposed approach enhances the dynamic response of the test systems substantially.