Autotuning of pid controllers: relay feedback approach
This book is intended to bridge the gap between conventional tuning and new generations of autotuning methods. As an independent learning tool it summarizes the achievements and investigates further possibilities of tuning practice. A simple and effective relay-feedback method for PID controllers is provided which covers most aspects of autotuning concerning single-input single-output as well as multivariable systems. Numerous examples and case studies are used to illustrate the proposed procedures in presence of noise, load disturbances, process nonlinearities, unstable zeros and poles. The mathematics of the subject is kept to a minimum level. The emphasis is laid on experimental design which gives relevant process information for the intended tuning rules. Simulation programs are built up in \(\text{MATLAB}^{\text{TM}}\). The book is structured into ten chapters. Review chapters provide background material and summarize the results of relay feedback identification experiments. One of the discussed key issues is to highlight how the information coming from relay experiment (using ideal, saturation, biased, ramp, dual-height, or some other ``shaped'' relay type), can be enhanced. In chapter 4 the conditions under which relay feedback experiment may fail are outlined. Among other factors the lack of process understanding, incorrect knowledge about the system, and the ignoring of process information is under investigation. The next chapters extend the method to multivariable systems, discuss the impact of load disturbances, process nonlinearities, and robustness. Also, the problems of performance improvement and autotuning for plantwide control systems are treated. The last chapter gives some useful guidelines to handle the autotune procedure in typical process conditions. The monograph provides an excellent indication of the depth to which the autotune culture has developed. Engineers and researchers working in the process control area will find it is an invaluable sourcebook. 156 references, 24 tables, 120 figures.
scientific article; zbMATH DE number 1497433