Practical Implementations of Advanced Process Control for Linear Systems

Research output: Contribution to conferenceConference abstract for conferenceResearchpeer-review


This paper describes some practical problems encountered, when implementing Advanced Process Control, APC, schemes on linear processes. The implemented APC controllers discussed will be LQR, Riccati MPC and Condensed MPC controllers illustrated by simulation of the Four Tank Process and a linearised CSTR. Advantages and disadvantages of these controllers will be discussed. All three controller types shows a set of common undesirable characteristics, which must be accounted for. At the end of the evaluation horizon the "optimal" solution has an unstable characteristics, which can be suppressed be selecting dierent control and evaluation horizon. Depending of the degrees of freedom, oset-free control of a number of the controlled variables can be achieved by integration of the innovation errors and introduction of noise models. If the measured or unmeasured disturbances increases, oset-free control cannot be achieved without violation of process constraints. A target calculation function can be used to calculate the optimal achievable target for the process. The use of hard and soft constraints for process input constraints in the MPC controllers, ensures feasible solutions. The computational load as function of controllers type, Model dimension and constraint type will be discussed. Finally the special requirements set by processes including a pure integration dynamics will be illustrated by a linearised CSTR process. The simulated results presented, will later on be implemented on and demonstrated on pilot
plant equipment on the department of Chemical Engineering DTU Lyngby.
Original languageEnglish
Publication date2013
Publication statusPublished - 2013
Event18th Nordic Process Control Workshop - University of Oulu, Oulu, Finland
Duration: 22 Aug 201323 Aug 2013


Conference18th Nordic Process Control Workshop
LocationUniversity of Oulu
Internet address


  • Advanced Process Control
  • Linear Quadratic Regulators
  • Disturbance Modelling
  • Offset Free control


Dive into the research topics of 'Practical Implementations of Advanced Process Control for Linear Systems'. Together they form a unique fingerprint.

Cite this