Fisher-Rosemount Systems, Inc

John A Gudaz

Terrence L Blevins

Wilhelm K Wojsznis

Mark J Nixon

Trevor Duncan Schleiss

Dirk Thiele

Marion A Keyes, Iv

Yan Zhang

A process control system uses a data collection and distribution system and an asset utilization suite to collect data or information pertaining to the assets of a process plant from various sources or functional areas of the plant including, for example, the process control functional areas, the maintenance functional areas and the process performance monitoring functional areas. This data and information is manipulated in a coordinated manner by the data collection and distribution system and is redistributed to other applications where this it is used to perform overall better or more optimal control, maintenance and business activities. Information or data may be collected by maintenance functions pertaining to the health, variability, performance or utilization of a device, loop, unit, area, etc. and this information may then be sent to and displayed to a process operator or maintenance person to inform that person of a current or future problem. A user interface is provided that enables users to access and manipulate the expert engine to optimize plant operation or cause optimization of plant operation, to get information about the operation of the plant, etc. Furthermore, applications, such as work order generation applications may automatically generate work orders, parts or supplies orders, etc. based on events occurring within the plant.

Method and apparatus for performing a function in a plant using process performance monitoring with process equipment monitoring and control

An adaptive process controller drives a process variable to be substantially equivalent to a set point and adapts the controller gain, the controller reset, and/or the controller rate, based on model free adaptation. The adaptive controller combines a controller gain computed from an oscillation index with a controller gain computed from a steady state estimate and that adapts the controller reset/rate by forcing the ratio of two of the controller proportional, integral or derivative terms to be equal to a predetermined value.

Model-free adaptation of a process controller

A simulation procedure simulates the response of a process control loop having a controller tuned according to a set of tuning parameters to illustrate, for example, the overshoot, oscillation, response time, etc. of the controller as tuned. As part of the simulation procedure, a robustness map, such as a plot illustrating phase margin versus gain margin or other robustness qualities, is created and the robustness of the simulated control loop may be plotted as a point on the robustness map. During the creation of the robustness map, different sets of tuning parameters for a region in which the process control loop is stable are determined and stored and the corresponding robustness qualities of the loop having a controller tuned according to these tuning parameters are also determined and stored. The robustness map is then displayed to a user showing the stable region. Thereafter, a user may select any point within the stable region on the robustness map and, upon doing so, a set of tuning parameters that will produce a control loop with the selected robustness characteristics will then be determined from the previously calculated sets of tuning parameters and robustness qualities. The simulation routine may then simulate the control loop using these new tuning parameters to enable a user to view the performance characteristics of the resulting control loop.

Determining tuning parameters for a process controller from a robustness map

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Bel Air, MD, United States of America

John A Gudaz