Uncertain Power System Control Based On T-S Fuzzy Model

Power systems are modeled by using Takagi-Sugeno(T-S)fuzzy model.Both fuzzy control and parallel distributed compensation(PDC)technology are used to study the stability of typical power systems in measurable states and partially measurable states.The concrete contents are given as follows:Firstly,a nonlinear uncertain simple interconnected power system is modeled via a T-S fuzzy model.When the states of the simple interconnected power system are measurable,a fuzzy controller is designed by using parallel distributed compensation and event-triggered mechanism.Based on Lyapunov stability theory,the stability of the system is analyzed,and sufficient conditions are provided to guarantee the asymptotic stability of the simple interconnected power system.The effectiveness of the proposed method is verified by MATLAB simulation.Secondly,uncertain nonlinear simple interconnected power systems are investigated when the states are not completely available based on the infinite approximation property of T-S models.A fuzzy observer is designed to estimate the states of the systems,and the fuzzy controller is given based on the observer by using parallel distributed compensation and event-triggered mechanism.The asymptotical stability of the closed-loop systems is analyzed based on Lyapunov stability theory,and the sufficient conditions of guaranteeing the stability of the systems are given in the form of linear matrix inequalities.A simulation example verifies the effectiveness of the proposed method.Thirdly,simply interconnected power systems with interference are modeled via a T-S fuzzy model,and a fuzzy H_?controller is designed using parallel distributed compensation and event-triggered mechanism when the states of a simple interconnected power system are measurable.Based on Lyapunov stability theory,the stability of the system is analyzed,and sufficient conditions are provided to guarantee the asymptotic stability of the nonlinear uncertain simple interconnected power system.The effectiveness of the proposed method is verified by MATLAB simulation.Finally,multi-machine power systems with uncertainty are modeled via T-S fuzzy models,and a fuzzy controller is designed by using parallel distributed compensation and event-triggered mechanism when the states of the multi-machine power system are measurable.Based on Lyapunov stability theory,the stability of the system is analyzed,and sufficient conditions are provided to guarantee the asymptotic stability of the system.The effectiveness of the proposed method is verified by MATLAB simulation.