Method of system state analysis

• US 4,937,763 A
• Filed: 09/06/1988
• Issued: 06/26/1990
• Est. Priority Date: 09/06/1988
• Status: Expired due to Term

• Current Assignee: SmartSignal Corporation (Emerson Electric Company)
• Original Assignee: E I International Incorporated
• Inventors: Mott, Jack E.
• Primary Examiner(s): Lall, Parshotam S.
• Assistant Examiner(s): ZANELLI, MICHAEL J
• Application Number:
  US07/240,262
• Time in Patent Office: 658 Days
• Field of Search: 364/550, 364/551.01, 364/552, 364/150, 364/571.02, 364/571.05, 364/492, 364/496, 364/148
• US Class Current: 702/183
• CPC Class Codes: G08B 23/00 Alarms responsive to unspecified undesired or abnormal conditions

Abstract

A process for monitoring a system by comparing learned observations acquired when the system is running in an acceptable state with current observations acquired at periodic intervals thereafter to determine if the process is currently running in an acceptable state. The process enables an operator to determine whether or not a system parameter measurement indicated as outside preset prediction limits is in fact an invalid signal resulting from faulty instrumentation. The process also enables an operator to identify signals which are trending toward malfunction prior to an adverse impact on the overall process.

Claims

1. In a multi-variable process, a method for controlling the process within predetermined process parameters, comprising the steps of:

a. capturing and recording a range of valid examples of a plurality of process variables when the process is running in an acceptable condition, and determining the pattern overlap of all pairs of such examples;

b. periodically acquiring current observations of the process variables and determining the pattern overlap of each such current observation of each of the examples of step a;

c. obtaining an operator from the pattern overlap of step a and applying it to the pattern overlap of step b to produce an adaptive linear combination of said examples;

d. comparing the current observations to the linear combination of step c to determine the validity of the current observation; and

e. indicating the results of step d to enable a determination to be made whether the current observation indicates the process to be operating within the range of valid examples of step a.

2. In a multi-variable process, a method of controlling the process within predetermined process parameters, comprising the steps of:

a. capturing and recording a range of valid examples of a plurality of process variables when the process is running in an acceptable condition, and determining the pattern overlap of all pairs of such examples;

b. periodically acquiring current observations of the process variables and determining the pattern overlap of each such current observation of each of the examples of step a;

c. obtaining an operator from the pattern overlap of step a and applying it to the pattern overlap of step b to produce an adaptive linear combination of said examples;

d. comparing the current observations to the linear combination of step c to determine the validity of the current observation;

e. indicating the results of step d to enable a determination to be made whether the current observation indicates the process to be operating within the range of valid examples of step a; and

f. indicating the results of step e. to enable a determination to be made whether the current observations contain valid examples of process variables.

3. In a multi-variable process, a method for controlling the process within predetermined process parameters, comprising the steps of:

a. capturing and recording a range of valid examples of process variables as learned observations;

b. deriving an operator from the learned observations and applying it to current observations to produce an adaptive linear combination of learned observations; and

c. comparing the current observations to the combination of learned observations to determine the validity of the current observations.

4. The method as recited in claim 3, further comprising indicating the results of step c to enable a determination to be made whether the current observation indicates the process and particular process variable to be operating within the range of valid examples.