System for monitoring an industrial process and determining sensor status

A method of operating a system to test at least one of a process and a sensor for determinining fault conditions therein, comprising the steps of:

• operating at least one sensor of the system to detect at least one variable of the process to provide a real signal from said one sensor;
• generating an artificial signal characteristic of the one variable;
• 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 difference function and the composite function;
• operating on the residual function using a computer for performing a statistical analysis technique to determine whether an alarm condition is present in at least one of the process and the at least one 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 at least one sensor providing a signal to said system allowing modification of at least one of the process and the at least one sensor when an alarm condition is detected.

A system for testing at least one of a process and a data source for determining a fault condition therein, comprising:

• at least a first data source to collect data of at least one variable of the process to provide a signal from said first data source;
• a second data source to collect data for comparison with said real signal from said first data source;
• means for determining a difference function characteristic of the arithmetic difference pairwise between said signals from said first and second data source at each of a plurality of different times of sensing the one variable;
• means for generating a composite function;
• 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;
• means for operating on the residual function including computer means for performing a statistical analysis technique and for determining whether an alarm condition is present in at least one of the process and the at least first and second data source, said means for obtaining a residual function and said means for operating on the residual function 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 process and the at least first data source when an alarm condition is detected.

A method of using a system for testing at least one of a process and at least a first and second data source for determining fault conditions therein, comprising the steps of:

• accumulating data from the at least first and second data source of the system to redundantly detect at least one variable of the process to provide a first signal from said first data source and a second signal from said second data source, each said signal being characteristic of the one variable;
• obtaining 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 variable;
• obtaining a frequency domain transformation of said first difference function to procure Fourier coefficients corresponding to Fourier frequencies;
• generating a composite function over time domain using the Fourier coefficients;
• obtaining a residual function over time by determining the arithmetic difference between the difference function and the composite function, the residual function including white noise characteristics of an uncorrelated function of reduced skewness relative to the difference function;
• operating on the residual function using computer means for performing a statistical analysis technique to determine whether an alarm condition is present in at least one of the process and the at least first and second data source;
• and
• said at least first and second data source providing a signal to the system which produces alarm information allowing modification of at least one of the process and the at least first and second data source when the alarm condition is detected by the system.

A method of operating a system for testing at least one of a process and at least one data source for determining fault conditions therein, comprising the steps of:

• using the at least one data source of the system to detect at least one variable of the process to provide a real signal from said at least one data source of the system;
• generating an artificial signal characteristic of the one variable using the system;
• 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 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 difference function and the composite function, the residual function comprising white noise characteristics of an uncorrelated signal of reduced skewness relative to the difference function;
• operating on the residual function using computer means for performing a statistical analysis technique to determine whether an alarm condition is present in at least one of the process and the at least one data source;
• and
• said at least one data source providing a signal to the system for generating alarm information to a user of the process allowing modification of at least one of the process and the at least one data source when the alarm condition is detected.