Advanced Topics in PID Control System Design, Automatic Tuning and Applications

Organisers

  • Liuping Wang
  • Antonio Visioli

Speakers

  • Tore Hägglund, Lund University, Sweden
  • Antonio Visioli, University of Brescia, Italy
  • Eric Rogers, University of Southampton, UK
  • Julio Elias Normey-Rico, Federal University of Santa Catarina (UFSC), Brazil
  • José Luis Guzmán Sánchez, University of Almería, Spain
  • Ramon Vilanova Arbos, Universitat Autonoma Barcelona, Spain
  • Sebastian Dormido, UNED, Spain
  • Toro Yammoto, Hiroshima University, Japan
  • Liuping Wang, RMIT University, Melbourne, Australia
  • YangQuan Chen, University of California, Merced, USA

Summary

PID control systems are the fundamental building blocks of classical and modern control systems. They have been used in the majority of industrial control systems  from chemical process control, mechanical process control, electromechanical process control, aerial vehicle control to electrical drive control and power converter control.
This workshop gathers together ten internationally renowned professors in the field of PID control systems to discuss the advanced topics in PID control system design, automatic tuning and applications. The workshop begins with Professor Hagglund to give a talk on an efficient mid-ranging control strategy based on feed-forward control. Professor Hagglund is one of the pioneers on automatic tuning of PID controllers.  Professor Visioli, who is the author of a few books on PID control, will give the second talk on performance assessment and re-tuning of PID control systems. Professor Rogers, who is an expert in iterative learning control, will deliver the third talk on PI type of iterative learning control with application to wind farms.   Professor Normey-Rico will address the issues of PID control with constraints in the fourth talk of this workshop. Professor Normey-Rico has done many industrial applications   including petroleum and natural gas production and renewable energies such as solar, wind, and biomass. In the fifth talk,  Professor  Sánchez will present advances in feedforward control for measurable disturbances.  Professor Vilanova, who is the author of  a book on robust PID control, will give the sixth talk on  robustness and robustness/performance tradeoff in PID control.   Professor  Dormido, who has vast experience in process control, will present  fundamentals on event-based PID control in the seventh talk of this workshop.  Professor Yamamoto, who has substantial industrial process control experience, will present the eighth talk on design and Industrial applications of a database-driven PID Controller.  Professor Wang, who is the author of several books on PID and predictive control, will present the ninth talk on automatic tuning of cascade control system with application to unmanned aerial vehicles.  In the final talk of this workshop, Professor Chen will deliver a talk on recent developments on fractional order PID.
The speakers of this workshop are enthusiastic in both teaching and research.  The presentations will be delivered in tutorial style. It  is suitable for industrial engineers, students and researchers who wish to gain basic  and advanced knowledge about design, automatic tuning and applications of PID control systems.

Programme

Welcome and introduction, Liuping Wang
 

An efficient mid-ranging control strategy based on feed-forward control, Tore Hägglund

The presentation starts with a short general discussion about the process control hierarchy and the important role that is played by the advanced process control structures in the regulatory control layer. Focus is then switched over to a newly developed strategy for mid-ranging control.


Performance assessment and retuning of PID controllers, Antonio Visioli

Methodologies that have been recently proposed to assess the deterministic performance of a PID controller will be reviewed. The main features of these methods are that they can be applied in closed-loop and they can exploit routine operational data. Further, the presented approach (which will be structured in different contexts) is based on the integral of signals, and it is therefore inherently robust to measurement noise. Illustrative examples will be shown.


PD and PI type Iterative Learning Control Laws for Application in Wind Farms, Eric Rogers

Current wind turbines are huge flexible structures and passive control is inefficient, resulting in the need for more powerful control action. For these reasons, research on improved rotor power and load control is a very relevant topic. This contribution will outline a role for iterative learning control in this area with wind farms in mind.  The tuning of designs based on simple structure control laws combined with smart actuators will be described with results generated by applying the control action to a computational fluid dynamics model of the flow


Coffee break
 

Advances in PID control for processes  with constraints, Julio Elias Normey-Rico

This talk presents  contributions  to improve the PID control implementation when it is desired to work with actuator saturation considering constraints in the magnitude and rate of the control signal, and in the magnitude of the process output. A simple but efficient technique derived from  the ideas of model predictive control is presented and it is shown that, if properly tuned, a simple PID  with anti-windup strategy could give a good trade-off between performance and simplicity, sometimes comparable to more sophisticated advanced control techniques.  A simulation tool, specially developed for the analysis of PID with anti-windup strategies in noisy environments, will be presented and used during the talk to illustrate the different concepts.


Advances in feedforward control for measurable disturbances, José Luis Guzmán Sánchez

This talk presents several contributions to improve the feedforward control approaches when inversion problem arise:  the ideal compensator may  not be realizable due to negative delay, having more zeros than poles, poles in the right-half plane, or in general non-minimum phase behaviours. New tuning rules will be presented for most of these situations when a PID controller is combined within a feedforward control scheme. Moreover, a robust design methodology for simultaneous feedback and feedforward tuning will be shown. Finally, new performances indexes are described to determine the contribution of typical feedforward schemes in literature.


Lunch break
 

PID tuning tackling design tradeoffs from an unified perspective, Ramon Vilanova

In this lecture attention is focused on model-based tuning of single-loop  PID controllers in terms of the robustness/performance and servo/regulator trade-offs. Although the robustness/performance compromise is commonly considered, it is not so common to also take into account, for example, the conflict between input and output disturbances, referred also as the servo/regulator trade-off. As interested in providing a unified tuning approach, it is shown how the proposed methodology allows to deal with different process dynamics in a unified way.


Fundamentals on event-based PID control, Sebastian Dormido

Many researchers have addressed the self-triggered approach and the event based sampling and control approach, in the context of PID controllers for the self-triggered strategies and for the event-based strategies). In this lecture, it will be presented the fundamentals and applications of event based PID control.  We will analyze the send on delta strategy and its different variants. This event based sampling mechanism can be considered as a multivalued relay control systems that provides interesting links with the nonlinear control field.


Design and Industrial Applications of a Database-Driven PID Controller, Toro Yammoto

A Database-Driven PID (DD-PID) controller stores a data set consisting of input/output (I/O) data in the database and uses this information to calculate control parameters in real time. The DD-PID controller has a self-learning mechanism to design and tune PID parameters in an online manner. In this presentation, the design scheme of the DD-PID controller will be explained followed by experimental evaluation of the proposed method on a computer-interfaced pilot-scale thermal process.


Automatic tuning of cascade PID control systems with application to UAV control, Liuping Wang

This talk will discuss cascade PID control system design, its role in disturbance rejection and overcoming actuator nonlinearity and automatic tuning of PID control systems. Attitude control of  unmanned aerial vehicles will be   used as an example to demonstrate the auto-tuners. The MATLAB/Simulink simulation programs for auto-tuner will be available on request.


Fractional order PID: recent developments, YangQuan Chen

In fractional order proportional derivative and integral controllers (FOPID), the order of differentiation/integration can be non-integer. It is now being accepted that the additional freedom in tuning the FOPIDs can offer better performance at the cost of extra implementation efforts. This talk will focus on first order plus time-delay (FOPTD) plants to illustrate that, FOPID can do better than the best of its integer order counterpart under fairness comparisons in terms of performance, robustness margins and even control energy consumption. This talk ends with a few recent progresses in fractional order controls such as 1) FO-[PID] 4 parameter tuning, 2) animation of feasible regions of FOPI, FO[PI] and IO-PID under fairness comparison conditions, 3) compensation of actuator rate limit issues and 4) idea of “more flat phase” design.