Suppression of Subsynchronous Resonance Torsional Torque Oscillations Using Type-2 Fuzzy Logic Brake Control

Abstract

Subsynchronous resonance (SSR) torsional torque oscillations remain a critical issue in power generation systems, as they can lead to severe mechanical stress, turbinegenerator shaft failures, and overall instability. This paper presents an advanced control strategy based on an interval type-2 fuzzy logic controller (IT2FLC) to regulate the interventions of a dynamic resistor brake (DRB) for effective SSR mitigation. The proposed controller outperforms traditional techniques in managing system uncertainties, nonlinearities, and dynamic variations. The IEEE Second Benchmark Model for SSR is employed as the test system, providing a recognized platform for evaluating the damping of torsional torque oscillations. The IT2FLC is implemented and tested in a MATLAB/Simulink simulation environment, utilizing the IT2FLC controller toolbox. Comparative simulation studies are performed against conventional fuzzy controllers and uncontrolled cases to assess performance. Results demonstrate that the IT2FLC-based DRB yields significant reduction in SSR oscillation amplitudes, faster damping times, and enhanced robustness under varying operating conditions, establishing its potential as a reliable tool for improving power system stability.