Method and system using wireless packet data networks architecture for remote process control and process monitoring applications

• US 8,787,202 B2
• Filed: 06/22/2010
• Issued: 07/22/2014
• Est. Priority Date: 06/22/2010
• Status: Active Grant

• Current Assignee: George W. Kuriyan
• Original Assignee: George W. Kuriyan
• Inventors: Kuriyan, George W.
• Primary Examiner(s): Sefcheck, Gregory
• Assistant Examiner(s): SMITH, JOSHUA Y
• Application Number:
  US12/820,276
• Publication Number:
  US 20110310743A1
• Time in Patent Office: 1,491 Days
• Field of Search: None
• US Class Current: 370/254
• CPC Class Codes: G08C 17/00 Arrangements for transmitting signals characterised by the use of a wireless electrical link
• CPC Class Codes: H04W 4/00 Services specially adapted for wireless communication networks; Facilities therefor
• CPC Class Codes: H04W 4/50 Service provisioning or reconfiguring
• CPC Class Codes: H04W 76/10 Connection setup

Abstract

A system for error avoidance and automatic recovery is combined with the accurate and reliable transmission system. The present invention provides a multi-variable control system using remote control with a wireless communication system. A plurality of closed loop control systems are connected through the wireless communication system. A master controller monitors the closing of each of the loops in the system and stores information for the status of the control loops in a control table at a control center. When a state variable is transmitted to the control center, a master controller notes that the initial value of the closed loop control system has been set. When the control center sends a control action to equipment or a process this closes the loop, the master controller notes that the closed loop control system has been closed for a particular time. If the closed loop control system does not get a loop closed, the control center immediately detects it. Thereafter, an alternative control action can be performed by the system.

Claims

1. A method for providing remote monitoring and control of remote processes comprising:

(a) establishing communications between a remote site and a control center by using a hardwired one to one connection protocol and a wireless communications medium;

(b) sending data from a plurality of the remote processes residing at said remote site to said control center using said wireless communications medium;

(c) storing said received data at said control center as a synchronized time series at said control center with up to date data at the remote site;

(d) monitoring said stored data at said control center as a synchronized time series at the remote site

(e) receiving input at said remote site from said control center over said wireless communications medium for establishing a plurality of control loops; and

(f) maintaining the reliability of said wireless communications medium at a high reliability level of the hardwired one to one connection protocol, wherein the high reliability level is less than about 1 error in substantially 1 million to 5 million message transmissions, wherein when said data is a RS232 signaling message a threshold error rate for retransmission of said signaling message is set to a predetermined value of a number of errors that can be accepted in said RS232 signaling message before a retransmissions of said RS232 signaling message.

2. The method of claim 1 wherein said data is time series data of the remote processes, the remote processes being an industrial process.

3. The method of claim 1 wherein a start point of said time series data is staggered with the start point of other time series data from the plurality of remote processes.

4. The method of claim 1 wherein said step of (b) includes a plurality of modem controllers at said remote site being controlled by a master modem controller.

5. The method of claim 1 wherein step (b) at said control center includes a plurality of modem controllers controlled by a master modem controller for maintaining the integrity of the wireless communication medium without any of the time series interfering with another one of the time series.

6. The method of claim 4 wherein said modem controllers include a buffer for storing said data and said data is stored and removed from said buffer with a FIFO scheme.

7. The method of claim 4 wherein said modem controllers include a buffer for storing said data and said data is stored and removed from said buffer with a LIFO scheme.

8. The method of claim 3 wherein before step (a) a channel of said wireless communication medium is set to operate at a predetermined average bit error rate.

9. The method of claim 8 wherein the average bit error rate is set below a threshold of forward error correction used in the channel of the wireless communication medium in order to increase the cumulative probability of accurate transmission to increase asymptotically to 100%.

10. The method of claim 9 further comprising the step of determining if the average bit error rate exceeds the threshold making it not possible to accurately receive data having the high reliability level on the channel and further comprising the step of:

switching to another channel of said wireless communications medium said channel is operating as previously set to the predetermined average bit error rate and repeating steps (b) through (f).

11. The method of claim 10 wherein there are at least three of said channels.

12. The method of claim 1 wherein said remote site and said control center communicate with layered protocols with separate layers for the wired communication protocol with an application layer and a lower layer conducting the entire wireless communications.

13. The method of claim 1 further comprising the step of:

using phase lead mechanisms in said process control loops for compensating for time delay caused by said wireless communication medium.

14. The method of claim 1 wherein said control center can monitor and change connection points of said remote site to different control loops at said remote site.

15. The method of claim 14 wherein said changes of said process control loops are determined by real-time simulation using data from the remote site.

16. The method of claim 14 wherein said control center includes an email interface and monitoring and changes to the process control loops can be managed from remote applications through said e-mail interface.

17. The method of claim 1 wherein the threshold is set to about 80 percent for receiving accurate binary coded digits (BCD) for providing the high reliability level.

18. The method of claim 15 wherein the wireless communication medium can be changed without changes to the remote processes at said remote site and said control center.

19. The method of claim 12 wherein there is an Application Layer which only deals with signaling between applications at the remote site and the control center, whereby data transfer from the remote site and the control center is synchronized within the time series.

20. The method of claim 13 wherein applications at the remote site and the control center achieve communications for the control loops eliminating inaccuracies resulting from time delays in communications.

21. The method of claim 1 further comprising the step of:

(g) verifying said data is accurate when said data is an information message by storing said data of said information message at said remote site in a sending buffer before step (b) of sending said data to said control center and receiving at said remote site said data of said information message from said control center and comparing said stored data at said remote site to said received data from said control center for errors, if no errors are present sending said data stored in said sending buffer to said control center or if errors are present retransmitting said data in said sending buffer to said control center and repeating steps (b)-(f).

22. A system for providing remote monitoring and control of remote processes comprising:

means for establishing communications between a remote site and a control center by using a hardwired one to one connection protocol and a wireless communications medium;

a plurality of the remote processes residing at said remote site and means for sending data from said processes to said control center over said wireless communications medium;

means for storing said received data at said control center as a synchronized time series at said control center with up to date data at the remote site;

means for monitoring said stored data at said control center as a synchronized time series at the remote site, and;

means for receiving input at said remote site from said control center over said wireless communications medium for establishing a plurality of control loops;

wherein the reliability of said wireless communications medium is maintained at a high reliability level of the hardwired connection protocol, wherein the high reliability level is less than about 1 error in substantially 1 million to 5 million message transmissions, wherein said data is a RS232 signaling message and a threshold error rate for retransmission of said signaling message is set to a predetermined value of a number of errors that can be accepted in said RS232 signaling message before a retransmissions of said RS232 signaling message.

23. The system of claim 22 wherein said data is time series data of the remote processes, the remote processes being an industrial process.

24. The system of claim 22 wherein a start point of said time series data is staggered with the start point of other time series data from the plurality of remote processes.

25. The system of claim 22 wherein said means for sending data from said processes includes a plurality of modem controllers controlled by a first master modem controller for establishing a connection between one of said first modem controllers and said wireless communication and said control center includes a plurality of second controllers controlled by a second master modem controller.

26. The system of claim 25 wherein said modem controllers include a buffer for storing said data and said data is stored and removed from said buffer with a FIFO scheme.

27. The system of claim 25 wherein said modem controllers include a buffer for storing said data and said data is stored and removed from said buffer with a LIFO scheme.

29. The system of claim 25 wherein there are at least three of said channels.

30. The system of claim 22 wherein said control center includes an email interface and said means for monitoring and changes to the process control loops can be managed from remote applications through said e-mail interface.

31. The method of claim 22 further comprising the step of:

means for verifying said data is accurate when said data is an information message by storing said data of said information message at said remote site in a sending buffer before sending said data to said control center and receiving at said remote site said data of said information message from said control center and comparing said stored data at said remote site to said received data from said control center for errors, if no errors are present sending said data stored in said sending buffer to said control center or if errors are present retransmitting said data in said sending buffer to said control center.

28. The system of 25 further comprising:

means for correcting an average bit error rate if the average bit error rate exceeds a threshold using either said first modem controller or said second modem controller by switching to another channel of said wireless communications medium wherein said another said channel is operating at the previously set predetermined average bit error rate.