Workshop on Fractional order control from practical point of view

Delft, Netherlands – November 5, 2019

Frequency domain analysis is a key for industry to understand and design controllers. In this event, the frequency domain analysis tools to design fractional order controllers were presented and discussed within 15 junior and senior researchers. The main contributions were given by:

  • Dr. Duarte Valerio, Universidade de Lisboa – Instituto Superior Técnico, Portugal, Basics and fundamental of fractional calculus
  • Dr. Niranjan Saikumar, Delft Univeristy of Technology, The Netherland, Fractional-order Precision Motion Control for Mechatronic Applications
  • Dr. Fabrizio Padula, Curtin Univeristy, Australia, Robust fractional PID control
  • Dr. Patrick Lanusse, Université de Bordeaux (CRONE team), France, CRONE Control methodology for SISO and/or MIMO and/or preview system

who within their presentations also gave some practical examples, which advantageously implemented fractional order control efficiently. The presentations of the speakers may be downloaded here, whereas their summary is below.

Participants of the Workshop on Fractional order control from practical point of view

Dr. Duarte Valerio – Basics and fundamental of fractional calculus

In this presentation we will go through all the fundamentals of Fractional Calculus, presented for beginners. A mathematical background in Calculus is assumed, but no previous knowledge of Fractional Calculus is required to follow this talk. The most usual definitions of fractional derivatives and integrals (the definitions known as Grünwald-Letnikoff, Riemann-Liouville and Caputo) will be presented, as well the corresponding Laplace transforms, from which fractional order transfer functions and state-space representations can be found and their time and frequency responses studied. Finally, a practical matter will be addressed: the different ways of approximating such fractional order dynamical systems by integer order transfer functions

Dr. Niranjan Saikumar – Fractional-order Precision Motion Control for Mechatronic Applications

Precision motion control design is highly competitive and challenging due to the ever increasing demands on speed and precision. In this lecture, we deal with the design of fractional order controllers specifically for precision motion systems. General guidelines will be provided for tuning fractional order PID. A toolbox (FLOreS) will be introduced for designing fractional order controllers using the industry standard loop-shaping technique. Finally, a practical example will be given to illustrate the advantage of fractional PID for precision motion control.

Dr. Fabrizio Padula – Robust fractional PID control

The ability of fractional controllers to improve the well-known performance/robustness trade-off that affect any control system has fueled the increasing interest in Fractional-Order Proportional-Integral-Derivative (FOPID) controllers in recent years. The talk will focus on two techniques that address the problem of designing robust FOPID controllers in the frequency domain. In particular, the model-matching approach, which hinges on the solution of an H-infinity optimal interpolation problem, and the so-called generalized isodamping approach, which recasts the FOPID design problem into an algebraic optimization problem, will be presented, along with a practical application.

Dr. Patrick Lanusse – CRONE Control methodology for SISO and/or MIMO and/or preview system

For 25 years, many developments have been proposed to make the CRONE control methodology both high performing and simple to be used by designers. Initially developed to design robust controllers for perturbed SISO systems, the CRONE methodology has been extended to MIMO systems and now to preview systems. Several experimental and industrial applications will show the efficiency of each step of the CRONE development.