Derek P. Atherton

Bio: Derek P. Atherton is an academic researcher from University of Sussex. The author has contributed to research in topics: PID controller & Describing function. The author has an hindex of 31, co-authored 215 publications receiving 5237 citations. Previous affiliations of Derek P. Atherton include University of New Brunswick & University of Brighton.

Automatic tuning of optimum PID controllers

Abstract: The paper first briefly reviews the analytical procedures for obtaining optimum PID controller settings for minimisation of time weighted integral performance criteria. The approach is then used to obtain formulae for setting the controller parameters for a first-order plus dead time plant model which is a common approximation used in the process industries. These results are further extended to obtain two procedures, which can be used with the relay autotuning approach, to find the required controller parameters for optimisation of the integral of time error squared criterion. Good results have been obtained when these criteria are used with other plant models.

Nonlinear Control Engineering

Abstract: Nonlinear control engineering , Nonlinear control engineering , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

Linear feedback control : analysis and design with MATLAB

Abstract: Preface 1. Introduction to feedback control 2. Mathematical models of feedback control systems 3. Analysis of Linear control systems 4. Simulation analysis of nonlinear systems 5. Model based controller design 6. PID controller design 7. Robust control systems design 8. Fractional-order controller - an introduction Appendix. CtrlLAB: a feedback control system analysis and design tool Bibliography Index of MATLAB functions Index.

An analysis package comparing PID anti-windup strategies

Abstract: This article describes software developed in SIMULINK that enables the behavior of feedback control systems with actuator saturation and PID controllers to be evaluated. The software, which is part command- and part menu-driven, allows a choice of four PID controllers using different integral wind-up strategies and transfer function entry of the actuator and plant dynamics. Most realistic control systems contain nonlinearities of some form. One nonlinearity commonly found in control systems is a saturating element. If integral control is applied to such a system to eliminate steady state error, an undesired side effect known as integrator windup may occur when large setpoint changes are made. This effect leads to a characteristic step response with a large overshoot and a very high settling time. To avoid this situation, many different anti-windup strategies have been suggested. This article discusses a software package that has been developed in the SIMULINK/MATLAB environment to investigate and compare the performance of four different anti-windup implementations for PI or PID controllers. The software is partially menu-driven and enables the user to easily enter his own actuator and plant transfer functions to study the performance with the different controllers. >

PID control system analysis, design, and technology

Abstract: Designing and tuning a proportional-integral-derivative (PID) controller appears to be conceptually intuitive, but can be hard in practice, if multiple (and often conflicting) objectives such as short transient and high stability are to be achieved. Usually, initial designs obtained by all means need to be adjusted repeatedly through computer simulations until the closed-loop system performs or compromises as desired. This stimulates the development of "intelligent" tools that can assist engineers to achieve the best overall PID control for the entire operating envelope. This development has further led to the incorporation of some advanced tuning algorithms into PID hardware modules. Corresponding to these developments, this paper presents a modern overview of functionalities and tuning methods in patents, software packages and commercial hardware modules. It is seen that many PID variants have been developed in order to improve transient performance, but standardising and modularising PID control are desired, although challenging. The inclusion of system identification and "intelligent" techniques in software based PID systems helps automate the entire design and tuning process to a useful degree. This should also assist future development of "plug-and-play" PID controllers that are widely applicable and can be set up easily and operate optimally for enhanced productivity, improved quality and reduced maintenance requirements.

Feedback Systems: An Introduction for Scientists and Engineers

Abstract: This book provides an introduction to the mathematics needed to model, analyze, and design feedback systems. It is an ideal textbook for undergraduate and graduate students, and is indispensable for researchers seeking a self-contained reference on control theory. Unlike most books on the subject, Feedback Systems develops transfer functions through the exponential response of a system, and is accessible across a range of disciplines that utilize feedback in physical, biological, information, and economic systems. Karl strm and Richard Murray use techniques from physics, computer science, and operations research to introduce control-oriented modeling. They begin with state space tools for analysis and design, including stability of solutions, Lyapunov functions, reachability, state feedback observability, and estimators. The matrix exponential plays a central role in the analysis of linear control systems, allowing a concise development of many of the key concepts for this class of models. strm and Murray then develop and explain tools in the frequency domain, including transfer functions, Nyquist analysis, PID control, frequency domain design, and robustness. They provide exercises at the end of every chapter, and an accompanying electronic solutions manual is available. Feedback Systems is a complete one-volume resource for students and researchers in mathematics, engineering, and the sciences.Covers the mathematics needed to model, analyze, and design feedback systems Serves as an introductory textbook for students and a self-contained resource for researchers Includes exercises at the end of every chapter Features an electronic solutions manual Offers techniques applicable across a range of disciplines