State Feedback Design using Standard Forms for Load Frequency Control

Abstract

This study proposes a state feedback-based controller design for Load Frequency Control (LFC) in isolated power systems employing a non-reheated turbine. The controller architecture integrates a proportional-integral (PI) control structure, with its tuning parameters analytically derived using standard forms, particularly based on the ISTE and IST 2E performance indices. The method allows direct computation of the PI controller gains without requiring iterative optimization procedures, thereby simplifying the design process. Comprehensive simulations reveal the effect of standard form parameters on the system's dynamic performance and demonstrate that the proposed method enhances both transient and steady-state responses under varying operating conditions. Compared to conventional PI-PD and PID controllers, the proposed ISTE and IST2 E methods achieve up to 38% improvement in settling time and a 72% reduction in peak value over PI-PD, and 52% improvement in settling time and 92% reduction in peak value over PID, respectively. These results highlight the practical advantages of the standard form approach, particularly in achieving robust and efficient LFC. © 2025 IEEE.