Determining tuning parameters for a process controller from a robustness map

A method of determining a set of tuning parameters for use in tuning a controller that is adapted to be used in a process control loop, the method comprising the steps of:

• determining a plurality of sets of tuning parameters for use in tuning the controller and an associated robustness quality for each of the plurality of sets of tuning parameters, wherein said plurality of sets of tuning parameters and associated robustness quality define a stable region within a robustness map;
• plotting the stable region of the robustness map to illustrate the robustness quality of the stable region;
• enabling a user to select a point within the robustness map;
• and
• using at least two of the plurality of sets of tuning parameters to determine a further set of tuning parameters, wherein said further set of tuning parameters is associated with the selected point within the robustness map and wherein the controller, when tuned according to the further set of tuning parameters, causes the process control loop to have approximately the robustness quality of the selected point.

A tuning system adapted to be used with a processor to tune a process control loop having a controller capable of being tuned according to a set of tuning factors, the tuning system comprising:

• a computer readable medium;
• a first routine stored on the computer readable medium and adapted to be executed on the processor to create a robustness map by determining a plurality of sets of tuning parameters for use in tuning the controller and an associated robustness quality for each of the sets of tuning parameters, wherein said plurality of sets of tuning parameters and associated robustness quality define a continuous region within the robustness map;
• a second routine stored on the computer readable medium and adapted to be executed on the processor to enable a user to select a point within the robustness map;
• and
• a third routine stored on the computer readable medium and adapted to be executed on the processor to use at least two of the determined plurality of sets of tuning parameters to generate a further set of tuning parameters which, when used to tune the controller, causes the process control loop to have the approximate robustness quality associated with the selected point.

A tuner for use in tuning a process control loop having a controller capable of being tuned with a set of tuning factors, the tuner comprising:

• a first element that creates a robustness map by determining a plurality of sets of tuning parameters for use in tuning the controller and two or more associated robustness qualities for each of the plurality of sets of tuning parameters, wherein said plurality of sets of tuning parameters and associated robustness qualities define a continuous region within the robustness map;
• a second element that enables a user to select a point within the robustness map;
• and
• a third element that uses at least two of the determined plurality of sets of tuning parameters to generate a further set of tuning parameters which, when used in the controller, causes the process control loop to have the approximate robustness qualities associated with the selected point.