Unknown input observer based robust control for fuzzy descriptor systems subject to actuator saturation

International audienceFor the stabilization problem of non linear system, a new control based on unknown input observer (UIO) is proposed to consider unknown inputs and actuators saturation. The proposed control method consists of designing an H∞ control for nonlinear systems based on TS fuzzy systems subject to unknown inputs and actuators saturation using the idea of UIO. To estimate state variables and unknown inputs, the unknown input observer is investigated. The saturation effect is considered through the polytopic representation. The descriptor representation is used to derive the new robust stabilization conditions of closed-loop system with unknown and constraints inputs. Both the UIO and controller gains are formulated as an optimization problem, which is expressed under Linear Matrix Inequalities (LMI). Simulations results are given to show the effectiveness of the proposed method

H ∞ fuzzy proportional integral state feedback controller of photovoltaic systems under asymmetric actuator constraints

International audienceThis paper presents a new strategy for a robust maximum power point (MPP) tracking fuzzy controller for photovoltaic (PV) systems subject to actuator asymmetric saturation. A DC-DC boost converter is used to connect a PV panel with an output load. The output voltage of the DC-DC boost converter can be adjusted by duty ratio that is limited between 0 and 1. The aim of our control design is to track the MPP under atmospheric condition changes and the presence of the asymmetric saturation of the duty ratio. To minimize tracking error and disturbance effect, the dynamic behaviour of a PV system and its reference model are described by using Takagi–Sugeno fuzzy models. Then, a constrained control based on a fuzzy PI state feedback controller is proposed. The H∞ control approach is used in control design and stability conditions of the closed-loop system are formulated and solved in terms of linear matrix inequalities. Finally, simulation results are given to show the tracking performance of the control design

Dynamic anti-windup controller design for Takagi-Sugeno fuzzy systems under saturations

International audienceThis paper presents a new H∞ anti-windup dynamic output control developed for a class of nonlinear systems subject to both sensors and actuators saturations. First, the nonlinear system under consideration is represented by a Takagi-Sugeno (T-S) fuzzy model. Then, a dynamic output feedback (DOF) control strategy is proposed and the saturation constraints are transformed into dead-zone nonlinearities. Based on this transformation and by using the sector condition, the H∞ dynamic output stabilization conditions of the closed-loop system are given in terms of linear matrix inequalities (LMI). Finally, a numerical example is simulated to demonstrate the efficiency of the proposed design method

Fuzzy reference model H∞H_{\infty} integral fuzzy maximum power tracking of WECS based-on DFIG

International audienceThis paper presents a new fuzzy control design for maximum power point tracking (MPPT) of wind energy conversion systems (WECS) using a doubly fed induction generator (DFIG) based on H∞ optimal control. In the first place, a new nonlinear reference model is developed for describing the optimal dynamic of the doubly fed induction generator (DFIG). In the second place, the nonlinear dynamic behaviour of the real system and its reference model are represented by a Takagi-Sugeno (TS) fuzzy model. Then, using a fuzzy proportional integral state feedback controller, a novel MPPT strategy for DFIG-based wind energy conversion systems is investigated. The H∞ criteria performance is used to design a robust fuzzy proportional integral state controller under varying wind speed. The H∞ stabilisation conditions are generated and given in terms of linear matrix inequalities (LMI). The estimation of the largest set invariance conditions are proposed as a LMI convex optimization problem. Finally, simulation results show that the proposed fuzzy integral state controller gives a good disturbance rejection and MPPT rapid convergence in the presence of wind's gusts

Abstracts of 1st International Conference on Computational & Applied Physics

This book contains the abstracts of the papers presented at the International Conference on Computational & Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational & Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria