Návrh robustného decentralizovaného PID regulátora : prípadová štúdia

Robust stability is an important aspect in control of real world systems, since uncertainties have to be considered in dynamic system model. This paper studies the robust decentralized controller design for case study: quadruple tank process, [3,4]. Several important aspects of system analysis are shown to choose appropriate pairing and assess stabilizability via decentralized control structure; the main contribution is in decentralized discrete-time controller design. Simulation results illustrate the obtained results and their qualities.Robustná stabilita je dôležitou stránkou pri návrhu riadenia reálnych systémov. Tento príspevok sa zaoberá návrhom robustného decentralizovaného regulátora pre prípadovú štúdiu: systém štyroch nádrží, [3,4]. Príspevok ilustruje niektoré dôležité aspekty analýzy systému potrebné na správny výber párovania vstupov a výstupov umožňujúci stabilizáciu systému decentralizovaným riadením; hlavným prínosom je návrh decentralizovaného diskrétneho algoritmu riadenia. Výsledky simulácie ilustrujú vlastnosti získaných regulátorov

Nonlinear modelling and optimal control via Takagi-Sugeno fuzzy techniques: A quadrotor stabilization

Using the principles of Takagi-Sugeno fuzzy modelling allows the integration of flexible fuzzy approaches and rigorous mathematical tools of linear system theory into one common framework. The rule-based T-S fuzzy model splits a nonlinear system into several linear subsystems. Parallel Distributed Compensation (PDC) controller synthesis uses these T-S fuzzy model rules. The resulting fuzzy controller is nonlinear, based on fuzzy aggregation of state controllers of individual linear subsystems. The system is optimized by the linear quadratic control (LQC) method, its stability is analysed using the Lyapunov method. Stability conditions are guaranteed by a system of linear matrix inequalities (LMIs) formulated and solved for the closed loop system with the proposed PDC controller. The additional GA optimization procedure is introduced, and a new type of its fitness function is proposed to improve the closed-loop system performance.Web of Science71110

Robust exponential stability of a class of nonlinear systems

summary:The paper addresses the problem of design of a robust controller for a class of nonlinear uncertain systems to guarantee the prescribed decay rate of exponential stability. The bounded deterministic uncertainties are considered both in a studied system and its input part. The proposed approach does not employ matching conditions

Discrete-Time Pole-Region Robust Controller for Magnetic Levitation Plant

Robust pole-placement based on convex DR-regions belongs to the efficient control design techniques for real systems, providing computationally tractable pole-placement design algorithms. The problem arises in the discrete-time domain when the relative damping is prescribed since the corresponding discrete-time domain is non-convex, having a “cardioid” shape. In this paper, we further develop our recent results on the inner convex approximations of the cardioid, present systematical analysis of its design parameters and their influence on the corresponding closed loop performance (measured by standard integral of absolute error (IAE) and Total Variance criteria). The application of a robust controller designed with the proposed convex approximation of the discrete-time pole region is illustrated and evaluated on a real laboratory magnetic levitation plant

Comparison of Nonlinear and Linear Controllers for Magnetic Levitation System

Nonlinear system control belongs to advanced control problems important for real plants control design. Various techniques have been developed in this field. In this paper we compare two different approaches to a nonlinear unstable Magnetic levitation system control. The first control design approach further develops our recent results on robust discrete-time pole-placement, based on convex DR-regions. The second studied approach is based on feedback linearization and the simplified development of the corresponding nonlinear control law is provided. Both approaches are compared and evaluated. The efficiency of robust discrete-time pole-placement controller is shown as well as its competitiveness in comparison with nonlinear control for Magnetic levitation system

Discrete-Time Pole-Region Robust Controller for Magnetic Levitation Plant

Robust pole-placement based on convex DR-regions belongs to the efficient control design techniques for real systems, providing computationally tractable pole-placement design algorithms. The problem arises in the discrete-time domain when the relative damping is prescribed since the corresponding discrete-time domain is non-convex, having a “cardioid” shape. In this paper, we further develop our recent results on the inner convex approximations of the cardioid, present systematical analysis of its design parameters and their influence on the corresponding closed loop performance (measured by standard integral of absolute error (IAE) and Total Variance criteria). The application of a robust controller designed with the proposed convex approximation of the discrete-time pole region is illustrated and evaluated on a real laboratory magnetic levitation plant

A necessary and sufficient condition for static output feedback stabilizability of linear discrete-time systems

summary:Necessary and sufficient conditions for a discrete-time system to be stabilizable via static output feedback are established. The conditions include a Riccati equation. An iterative as well as non-iterative LMI based algorithm with guaranteed cost for the computation of output stabilizing feedback gains is proposed and introduces the novel LMI approach to compute the stabilizing output feedback gain matrix. The results provide the discrete- time counterpart to the results by Kučera and De Souza