Process control system using a process control strategy distributed among multiple control elements

• US 20020013629A1
• Filed: 01/02/2001
• Published: 01/31/2002
• Est. Priority Date: 04/12/1996
• Status: Abandoned Application

• Current Assignee: Arthur Webb, Dennis Stevenson, Larry O. Jundt, Mark Nixon, Michael G. Ott, Mike Lucas, Robert B. Havekost
• Original Assignee: Arthur Webb, Dennis Stevenson, Larry O. Jundt, Mark Nixon, Michael G. Ott, Mike Lucas, Robert B. Havekost
• Inventors: Nixon, Mark, Webb, Arthur, Lucas, Mike, Havekost, Robert B., Jundt, Larry O., Stevenson, Dennis, Ott, Michael G.
• Application Number:
  US09/753,754
• Publication Number:
  US 20020013629A1
• Time in Patent Office: Days
• US Class Current: 700/4
• CPC Class Codes: G05B 19/0421 Multiprocessor system
• CPC Class Codes: G05B 2219/23261 Use control template library
• CPC Class Codes: G05B 2219/23298 Remote load of program, through internet
• CPC Class Codes: G05B 2219/23299 Remote load of program, through fieldbus
• CPC Class Codes: G05B 2219/23424 Select construction element from function library
• CPC Class Codes: G05B 2219/25232 DCS, distributed control system, decentralised control unit
• CPC Class Codes: G05B 2219/25323 Intelligent modules
• CPC Class Codes: G05B 2219/25428 Field device
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

A process controller implements an overall, user-developed control strategy in a process control network that includes distributed controller and field devices, such as Fieldbus and non-Fieldbus devices. A user defines the control strategy by building a plurality of function blocks and control modules and downloading or installing user-specified portions of the control strategy into the Fieldbus devices and the non-Fieldbus devices. Thereafter, the Fieldbus devices automatically perform the downloaded portions of the overall strategy independently of other portions of the control strategy. For example in a process control system that includes distributed field devices, controllers and workstations, portions of the control strategy downloaded or installed into the field devices operate independently of and in parallel with the control operations of the controllers and the workstations, while other control operations manage the Fieldbus devices and implement other portions of the control strategy.

Claims

1. A process control system comprising:

a field device;

a controller coupled to the field device;

a workstation coupled to the controller, and

a software system implementing a control strategy for the process control system, the control strategy being selectively apportioned into a plurality of control strategy modules and selectively distributed among the field device, controller and workstation, the control strategy modules operating mutually independently and in parallel.

2. A process control system according to claim 1, wherein:

the software system further includes a user interface for interfacing the process control system to a user; and

the control strategy is selectively apportioned and selectively distributed by the user.

3. A process control system according to claim 1, wherein:

the field device includes a control element; and

the software system includes a control strategy module that is distributed to the field device.

4. A process control system according to claim 1 wherein

the field device is a Fieldbus standard device including a control element;

and

a control strategy module is distributed to the control element and operates as a Fieldbus standard function block.

5. A process control system according to claim 1, further comprising:

a plurality of field devices including a Fieldbus standard field device and a non-Fieldbus standard device.

6. A process control system according to claim 1 wherein the software system further includes:

a configuration program for configuring the control strategy modules and installing the control strategy modules among the field device, controller and workstation, the distributed controllers retaining the configuration until reconfigured.

7. A process control system according to claim 1, wherein the control strategy modules are selectively installable by downloading a selected control strategy module to a selected one of the field device, controller and workstation.

8. A process control system according to claim 1, wherein the control strategy modules are objects in an object-oriented environment.

9. A process control system according to claim 1 wherein the plurality of control strategy modules are configured into a communication services hierarchy including:

a remote object communications (ROC) level for communicating messages between two control strategy modules in a same controller and between two control strategy modules in different controllers, and

a low level communications level for interfacing with communications hardware and transmitting messages across the communications hardware.

10. A process control system according to claim 1, wherein the control strategy modules include a device connection object for controlling data transfers between a plurality of devices, transmitting data, maintaining communication link status between two communicating devices and establishing a communication link upon demand of a remote device.

11. A process control system comprising:

a field device;

a control means coupled to the field device for controlling the field device;

an interface means coupled to the control means for interfacing the control process system to a user; and

a control strategy means for implementing a process control strategy, the control strategy means being selectively apportioned into a plurality of control strategy modules and selectively distributed among the field device, control means and interface means, the control strategy modules operating mutually independently and in parallel.

12. A process control system according to claim 11, wherein:

the control strategy means is selectively apportioned into control strategy modules and selectively distributed among the field device, control means and interface means by the user.

13. A process control system according to claim 11, wherein:

the field device includes a field device control means for controlling field device operations; and

the control strategy means includes a control strategy module that is distributed to and operational upon the field device control means.

14. A process control system according to claim 11 wherein

the field device is a Fieldbus standard device including a field device control means for controlling Fieldbus standard operations;

and

a control strategy module is distributed to the field device control means and operates as a Fieldbus standard function block.

15. A process control system according to claim 11, further comprising:

a plurality of field devices including a Fieldbus standard field device and a non-Fieldbus standard device.

16. A process control system according to claim 11 wherein the control strategy means further includes:

a configuration means for configuring the control strategy modules and installing the control strategy modules among the field device, control S means and interface means, the distributed controllers retaining the configuration until reconfigured.

17. A process control system according to claim 11, wherein the control strategy means are selectively installable by downloading a selected control strategy means to a selected one of the field device, control means and interface means.

18. A process control system according to claim 11, wherein the control strategy means are objects in an object-oriented environment.

19. A process control system according to claim 11 wherein the plurality of control strategy means are configured into a communication services hierarchy including:

a remote object communications (ROC) level for communicating messages between two control strategy means in a same controller and between two control strategy means in different controllers, and

a low level communications level for interfacing with communications hardware and transmitting messages across the communications hardware.

20. A process control system according to claim 11, wherein the control strategy means include a device connection object for controlling data transfers between a plurality of devices, transmitting data, maintaining communication link status between two communicating devices and establishing a communication link upon demand of a remote device.

21. A method of operating a process control system including a distributed controller and a distributed field device comprising the steps of:

defining a control strategy including the steps of;

building a plurality of function blocks and control modules; and

downloading user-specified function blocks and control modules selectively among the distributed controller and the distributed field device;

executing the function blocks and control modules distributed to the controller and distributed to the field device mutually independently and in parallel.

22. A method according to claim 21 wherein the process control system includes a plurality of distributed controllers and a plurality of distributed field devices, the field devices including Fieldbus standard devices executing Fieldbus standard function blocks.

23. A method according to claim 21 wherein the process control system includes a plurality of distributed controllers and a plurality of distributed field devices, the field devices including Fieldbus standard devices executing Fieldbus standard function blocks and nonFieldbus standard devices executing in the manner of Fieldbus standard function blocks