Weighted average algorithm adjusted a novel (1 + FOPI)-FOPI-TID controller structure for AGC with integration of...

Area of Science:

• Electrical Engineering
• Control Systems
• Power Systems

Background:

• Modern power systems face significant load frequency management (LFM) challenges due to diverse energy sources, smart grid integration, and inherent nonlinearities.
• System vulnerabilities include generation rate constraints, governor dead bands, boiler dynamics, communication delays, and sophisticated cyber-attacks, threatening frequency stability and tie-line power balance.

Purpose of the Study:

• To propose a novel, robust cascade controller, (1+FOPI)-FOPI-TID, for automatic generation control (AGC) in hybrid two-area power systems.
• To optimize the controller using a green metaheuristic, the weighted average algorithm (WAA), for enhanced parameter tuning.
• To evaluate the controller's performance and resilience against nonlinearities and cyber-attacks in AC and HVDC tie-line configurations.

Main Methods:

• A cascade controller combining fractional-order (FO) elements with a tilt-integral-derivative (TID) stage was designed.
• The weighted average algorithm (WAA), a green metaheuristic, was employed for optimizing controller parameters.
• System modeling incorporated nonlinearities, and performance was evaluated under various scenarios, including cyber-attacks and parameter variations.

Main Results:

• The WAA-optimized (1+FOPI)-FOPI-TID controller demonstrated superior performance compared to existing schemes (PD-PI, PIFOD-(1+PI), PIDF(1+FOD)).
• Significant improvements were observed: 45.3% reduction in ITAE, 47.7% settling time improvement for ΔF₁, and 32.8% for ΔF₂.
• The controller exhibited robustness against parameter variations and load perturbations, and maintained the lowest Rate of Change of Frequency (RoCoF) during cyber-attacks.

Conclusions:

• The proposed (1+FOPI)-FOPI-TID controller offers a robust solution for AGC in complex power systems.
• The WAA optimization technique effectively enhances controller parameter tuning.
• The controller's dual capability in stabilizing grid dynamics and mitigating cyber-physical threats highlights its potential for future smart grids.