Aspen Technology, Inc.
Apparatus and Methods for Non-Invasive Closed Loop Step Testing with Controllable Optimization Relaxation

Abstract:

A controller has improved closed-loop step testing of a dynamic process of an industrial processing plant. The controller performs economic optimization relaxation on process variables, such that operating range of the variables (MVs and CVs) during the testing are not skewed by variations in optimization cost factors. The controller employs computer-implemented methods and systems that receive a user-defined giveaway tolerance representing an allowable range between a current process variable value and a target process variable value. In response to the variables not meeting the giveaway tolerance, the methods and systems adjust the MPC controller configuration to drive the variables inside the tolerance, while relaxing optimization of the variables already meeting the giveaway tolerance. Using the adjusted configuration, the methods and systems calculate a new set of targets and generate a dynamic move plan from the new target. The methods and systems add perturbation signals for the testing to the move plan in accordance with the adjusted configuration.