Expert system for testing industrial processes and determining sensor status

A method of testing both an industrial process and a sensor for determining fault conditions therein, comprising the steps of:

• determining, using computer means, a configuration of a minimum number of sensor pair signals needed to characterize the industrial process and the sensor state of operation;
• operating at least a first sensor to detect at least one physical variable of the industrial process to provide a real signal from said first sensor;
• generating an artificial signal characteristic of the one physical variable;
• forming a sensor pair signal from said real signal and said artificial signal;
• obtaining a difference function characteristic of the difference pairwise between said real signal and said artificial signal at each of a plurality of different times of sensing the one physical variable;
• obtaining a frequency domain transformation of said difference function;
• generating a composite function over a time domain;
• obtaining a residual function over time by determining the difference between the frequency transformed difference function and the composite function;
• operating on the residual function using the computer means for performing a statistical analysis technique to determine whether an alarm condition is present in at least one of the industrial process and the first sensor, the residual function including white noise characteristics of an uncorrelated signal of reduced skewness relative to the difference function and being input to the statistical analysis technique;
• and
• said first sensor providing alarm information to an operator of the industrial process allowing modification of at least one of the industrial process and the first sensor when an alarm condition is detected.

A system for automatically configuring sensors for testing both an industrial process and a sensor for determining a fault condition therein, comprising:

• computer means for automatically configuring a minimum number of sensor pair signals needed to characterize the industrial process and the sensor state of operation;
• at least a first sensor to detect at least one physical variable of the industrial process to provide a first signal from said first sensor;
• first means for generating a second sensor signal for comparison with said first signal from said first sensor;
• second means for determining a difference function characteristic of the arithmetic difference pairwise between said first signal and said second signal at each of a plurality of different times of sensing the one physical variable;
• third means for obtaining a residual function over time by means for determining the arithmetic difference between the difference function and the composite function, the residual function including white noise characteristics of an uncorrelated signal of reduced skewness;
• fourth means for operating on the residual function, said fourth means including the computer means for executing a computer program for performing a statistical analysis technique and for determining whether an alarm condition is present in at least one of the industrial process and the sensor and with said second means, said third means, and said fourth means cooperatively providing a function comprised of said white noise characteristics of uncorrelated signal of reduced skewness relative to the difference function as an input to the statistical analysis technique;
• and
• means for providing information allowing modification of at least one of the industrial process and the sensor when an alarm condition is detected.