Designing decentralized adaptive fuzzy stabilizer in nonlinear multi-machine power system with unknown dynamic

This paper presents a decentralized adaptive fuzzy controller for power system stabilizer (PSS) design to damping low-frequency oscillations of nonlinear multi-machine power systems with unknown dynamics. In the proposed method, the fuzzy system is an unknown dynamic estimator of the used power system. Also, to solve the singularity issue of the controller, the estimated gain matrix is separated into a multiplication of a diagonal matrix two orthogonal matrices. Additionally, to compensate for large errors, we have used a control resistor term. Adaptive rules parameters and terms related to the robust control part are obtained using Lyapunov stability analysis. The proposed method ensures that all signals from closed-loop are bounded and uniform. To show the capabilities and abilities of the proposed method, numerical studies on the nonlinear 6-bus system are provided. Also, to show the robustness of the designed stabilizer, we have applied the type of three-phase and one-phase error to the system. Results from the simulation show the capability and ability of the designed stabilizer.