LMI static output-feedback design of fuzzy power system stabilizers

The design of a model-free fuzzy power system stabilizer (PSS) lacks systematic stability analysis and performance guarantees. This paper provides a step towards the design of a model-based fuzzy PSS that guarantees not only stability but also performance specifications of power systems. A new practical and simple design based on static output feedback is proposed. The design guarantees robust pole-clustering in an acceptable region in the complex plane for a wide range of operating conditions. A power system design model is approximated by a set of Takagi–Sugeno (T–S) fuzzy models to account for nonlinearities, uncertainties and large scale power systems. The proposed PSS design is based on parallel distributed compensation (PDC). Sufficient design conditions are derived as linear matrix inequalities (LMI). The design procedure leads to a tractable convex optimization problem in terms of the stabilizer gain matrix. Simulations results of both single-machine and multi-machine power systems confirm the effectiveness of the proposed PSS design.