Actuator saturation is probably the most frequent nonlinearity encountered in control applications. Input saturation leads to controller windup, removable by structural modification during compensator realization and plant windup which calls for additional dynamics.

Peter Hippe presents solutions to the windup prevention problem for stable and unstable single-input-single-output and multiple-input-multiple-output (MIMO) systems. The solutions use only standard tools for the investigation of linear systems a" state equations, transfer functions, etc. The stability tests are based on well-known criteria for loops consisting of a linear part with isolated sector-type nonlinearity. Less rigorous "engineering solutions" which guarantee improved performance but without strict proof of stability are also demonstrated.

MIMO systems in which the behaviour of controlled variables is decoupled require specific input vectors and so also suffer problems of directionality when their input signals saturate. This can have extremely deleterious consequences for closed-loop behaviour. Windup in Control offers an exact solution to this directionality problem for stable and unstable systems. The methods laid out in this survey also integrate solutions for applications with rate-constrained actuators and for bumpless transfer from manual to automatic during system start-up or in override control. Developments in control methods are always supplemented by easily repeated numerical examples.

Academics doing control-related research in electronics, mechanics, or mechatronics and engineers working in the process industries will find this book an extremely useful overview of systematic windupprevention for all kinds of systems. It also has valuable insights to offer the graduate student of control.

Design of Observer-based Compensators facilitates and adds transparency to design in the frequency domain which is not as well-established among control engineers as time domain design. The presentation of the design procedures starts with a review of the time domain results; therefore, the book also provides quick access to state space methods for control system design.

Frequency domain design of observer-based compensators of all orders is covered. The design of decoupling and disturbance rejecting controllers is presented, and solutions are given to the linear quadratic and the model matching problems. The pole assignment design is facilitated by a new parametric approach in the frequency domain. Anti-windup control is also investigated in the framework of the polynomial approach. The discrete-time results for disturbance rejection and linear quadratic control are also presented.

The book contains worked examples that can easily be reproduced by the reader, and the results are illustrated by simulations.

Design of Observer-based Compensators facilitates and adds transparency to design in the frequency domain which is not as well-established among control engineers as time domain design. The presentation of the design procedures starts with a review of the time domain results; therefore, the book also provides quick access to state space methods for control system design. Frequency domain design of observer-based compensators of all orders is covered. The design of decoupling and disturbance rejecting controllers is presented, and solutions are given to the linear quadratic and the model matching problems. The pole assignment design is facilitated by a new parametric approach in the frequency domain. Anti-windup control is also investigated in the framework of the polynomial approach. The discrete-time results for disturbance rejection and linear quadratic control are also presented. The book contains worked examples that can easily be reproduced by the reader, and the results are illustrated by simulations.

Actuator saturation is probably the most frequent nonlinearity encountered in control applications. Input saturation leads to controller windup, removable by structural modification during compensator realization and plant windup which calls for additional dynamics. This book presents solutions to the windup prevention problem for stable and unstable single-input-single-output and multiple-input-multiple-output (MIMO) systems.

This brief presents methods for anti-windup control in the presence of saturating sensors, arbitrary external reference inputs, and constant or step-like disturbance inputs. It also offers techniques to assure windup prevention when both the input and the output signals are limited and this for systems with one input (SISO) and multiple inputs (MIMO). The emphasis in both is on real-world practicality rather than rigorously proven stability. Two novel solutions for anti-windup control are explored. The first approach, for SISO systems only, follows the classic design paradigm of anti-windup control: design an arbitrary linear compensator and add appropriate measures for their prevention if saturation causes stability problems. This uses a saturation indicator detecting the presence, but not the extent of saturation. The second methodology uses a compensator design that assures the desired rejection of persistent disturbances without jeopardizing closed-loop stability, and can be applied to SISO and MIMO systems alike. Containing worked examples that can be reproduced by the reader, illustrative simulations, and open problems for future research, Windup in Control Owing to Sensor Saturation will be of interest to both academics and engineers in the fields of control and process industries.

Ein nicht ins Detail gehender RUckblick auf die Entwicklung der Regelungstechnik in den vergangenen zwei bis drei Jahrzehnten laGt erkennen, daG deutlicher als in der davor liegenden Zeit die verschiedenen Regelungskonzepte fast synchron mit der zunehmend detaillierteren Beschreibung der zu regelnden Strecken und Anlagen ent- standen sind. FUr einen langen Zeitabschnitt waren auf den klassischen, stetig und unstetig ar- beitenden Regler-Grundtypen fuGende Konzepte wie Vorregelung, StorgroGenaufschal- tung, zusatzliche Regelschleifen mit Hilfsregel- und HilfsstellgroGen dominierend. Diese Konzepte waren zum Teil zweifelsfrei Vorlaufer dessen, was wir heute unter "Zustandsregelung" verstehen. Die Wurzeln dieser Begriffswelt reichen jedoch noch viel weiter in den Grundlagen- bereich der Physik hinein als man heute gemeinhin zum Ausdruck bringt. Hier ist zunachst der Begriff der enorm ausgebauten und verfeinerten Modellbildung zu nennen, die im Grunde genommen schon in dem Augenblick vollzogen wird, in dem man einen naturwissenschaftlich gesicherten Sachverhalt in eine mathematische Form bringt. Mit der Verfeinerung dieser Modellbildung erhebt sich fUr den Regelungs- techniker zwangslaufig die Frage nach der Ausnutzbarkeit genauerer Streckenkennt- nisse fUr entsprechend ausgefeilte und angepaGte Regelungskonzepte.