Plug-and-play control of interconnected systems


Book Description

In the networked control of interconnected systems, the communication network is primarily used for the exchange of measurements amongst the control stations. Plug-and-play control extends the usage of this network towards the exchange of models with the aim to automatically design control stations at runtime. Therefore, every subsystem is equipped with a design agent that initially knows only the model of its subsystem. To design a control station by a design agent, first, a suitable model of the subsystem that interacts with other subsystems has to be set up. Second, local design conditions have to be found that guarantee the adherence of the global control aim. If the designed control station is finally plugged into the control equipment, the overall closed-loop system plays as desired. The focus of this thesis is to enable the design agent to accomplish the controller design. Therefore, three approaches are proposed which focus on the accuracy of the model that is used for the design with respect to the achievable overall closed-loop performance. The main result is a novel concept for the self-organised controller design by means of design agents. This concept is applied to achieve fault tolerance and to integrate new subsystems. The proposed methods are tested and evaluated through simulations and experiments on a thermofluid process and a multizone furnace.




Self-organizing control of networked systems


Book Description

This thesis presents a novel distributed control paradigm for networked control systems in which the local control units of the subsystems exchange information, whenever this is necessary to fulfill an overall control aim. The local control units act in a self-organized way, which means that they adapt their communication structure depending on the current situation of the subsystems based on locally available information only. A new controller structure is proposed. The local control units are divided into three components fulfilling universal tasks to generate a situation-dependent communication structure: The feedback unit performs a local feedback by using local measurements to fulfill basic performance requirements. The observation unit detects the current situation of the subsystem by evaluating locally available information. The decision unit decides about the transmission of information from the corresponding subsystem to other local control units. Two self-organizing controllers for physically interconnected systems in which the local control units adapt the communication among each other depending on the current disturbances are introduced. Furthermore, three novel self-organizing controllers for synchronizing multi-agent systems within leader-follower structures by adapting the communication structure to situations like set-point changes, disturbances and communication faults are proposed. The concepts are applied in order to control a water supply system and a robot formation.




Automated Model Generation and Observer Design for Interconnected Systems : A Port-Hamiltonian Approach


Book Description

This work addresses the automated generation of physical-based models and model-based observers. We develop port-Hamiltonian methods, which for the first time allow a complete and consistent automation of these two processes for a large class of interconnected systems.




Advanced Control of AC / DC Power Networks


Book Description

The power engineering domain is facing huge challenges, with an increasing interest in intermittent renewable energies which are imposing major technical limitations. Operating ever closer to their limits, the industry-standard AC power grids are subject to instabilities. This book presents an insight into DC grid systems, offering interesting issues to well controlled power grids, in contrast to current AC systems which provide the simplest and most economic connection method for short distances.







Multi-Paradigm Modelling Approaches for Cyber-Physical Systems


Book Description

Multi-Paradigm Modelling for Cyber-Physical Systems explores modeling and analysis as crucial activities in the development of Cyber-Physical Systems, which are inherently cross-disciplinary in nature and require distinct modeling techniques related to different disciplines, as well as a common background knowledge. This book will serve as a reference for anyone starting in the field of CPS who needs a solid foundation of modeling, including a comprehensive introduction to existing techniques and a clear explanation of their advantages and limitations. This book is aimed at both researchers and practitioners who are interested in various modeling paradigms across computer science and engineering. Identifies key problems and offers solution approaches as well as tools which have been developed or are necessary for modeling paradigms across cyber physical systems Explores basic theory and current research topics, related challenges, and research directions for multi-paradigm modeling Provides a complete, conceptual overview and framework of the research done by the MPM4CPS working groups and the different types of modeling paradigms developed







Fault Detection, Supervision and Safety of Technical Processes 2006


Book Description

The safe and reliable operation of technical systems is of great significance for the protection of human life and health, the environment, and of the vested economic value. The correct functioning of those systems has a profound impact also on production cost and product quality. The early detection of faults is critical in avoiding performance degradation and damage to the machinery or human life. Accurate diagnosis then helps to make the right decisions on emergency actions and repairs. Fault detection and diagnosis (FDD) has developed into a major area of research, at the intersection of systems and control engineering, artificial intelligence, applied mathematics and statistics, and such application fields as chemical, electrical, mechanical and aerospace engineering. IFAC has recognized the significance of FDD by launching a triennial symposium series dedicated to the subject. The SAFEPROCESS Symposium is organized every three years since the first symposium held in Baden-Baden in 1991. SAFEPROCESS 2006, the 6th IFAC Symposium on Fault Detection, Supervision and Safety of Technical Processes was held in Beijing, PR China. The program included three plenary papers, two semi-plenary papers, two industrial talks by internationally recognized experts and 258 regular papers, which have been selected out of a total of 387 regular and invited papers submitted. * Discusses the developments and future challenges in all aspects of fault diagnosis and fault tolerant control * 8 invited and 36 contributed sessions included with a special session on the demonstration of process monitoring and diagnostic software tools