Dead time process regulation

Claim 1

In a method for regulation of processes having dead time comprising the steps of: generating a status signal representing the value of a controlled variable in said process; generating a set point signal representing a predetermined standard value of said controlled variable; comparing said status signal to said set point signal; and generating in response to said comparing step an error signal representing quantitatively the amount said status signal exceeds said set point signal; the improvement thereto comprising the additional steps preestablished determining whether said error signal exceeds a pre-established error value or not; passing said error signal onto regulatory apparatus in order to regulate said process if said determining step indicates said error signal exceeds said pre-established error value; and impressing a perturbation into said process to calculate the dead time thereof if said determining step indicates said error signal does not exceed said pre-established error value.

Claim 6

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the deviation of said controlled variable from a predetermined set point; comparing said first signal to a predetermined error signal and determining whether said first signal is less than said predetermined error signal; impressing at a first process station a disturbance signal onto said process at a time T1 in response to said determination that said first signal is less than said predetermined error signal; filtering out said disturbance when received at a second process station at a time T2; and calculating process dead time between said stations by determining the time difference between T1 and T2.

Claim 7

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the deviation of said controlled variable from a predetermined set point; comparing said first signal to a predetermined error signal and determining whether said first signal is less than said predetermined error signal; impressing at a first process station a disturbance signal onto said process at a time T1 in response to said determination that said first signal is less than said predetermined error signal; filtering out said disturbance when received at a second process station at a time T2; and calculating process dead time between said stations by determining the time difference between T1 and T2.

Claim 8

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the deviation of said controlled variable from a predetermined set point; comparing said first signal to a predetermined signal representing a predetermined error limit; impressing at the process input a disturbance signal onto said process at a time T1 in response to said determination that said first signal is within said predetermined error limit; filtering out said disturbance when received at a process station at a time T2; and calculating process dead time between said process input and said station by determining the time difference between T1 and T2.

Claim 9

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the deviation of said controlled variable from a predetermined set point; comparing said first signal to a predetermined signal representing a predetermined error limit; impressing at the process input a disturbance signal onto said process at a time T1 in response to said determination that said first signal is within said predetermined error limit; filtering out said disturbance when received at a process station at a time T2; and calculating process dead time between said process input and said station by determining the time difference between T1 and T2.

Claim 10

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the deviation of said controlled variable from a predetermined set point; generating a second signal representative of some predetermined error limit of said controlled variable; comparing said first signal to said second signal, thereby determining whether said controlled variable is within said predetermined error limit; impressing upon said controlling variable a disturbance signal at time T1 in response to said determination that said controlled variable is within said predetermined error limit; filtering out said disturbance when received at a station associated with said controlled variable at a time T2; and calculating process dead time by determining the time difference between T1 and T2.

Claim 11

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the deviation of said controlled variable from a predetermined set point; generating a second signal representative of some predetermined error limit of said controlled variable; comparing said first signal to said second signal, thereby determining whether said controlled variable is within said predetermined error limit; impressing upon said controlling variable a disturbance signal at time T1 in response to said determination that said controlled variable is within said predetermined error limit; filtering out said disturbance when received at a station associated with said controlled variable at a time T2; and calculating process dead time by determining the time difference between T1 and T2.

Claim 12

A method for determining the dead time of a regulated process having a controlled and controlling variable so as to update a mathematical model of said process, comprising the steps of: measuring said controlled variable to generate a signal representative of the controlled variable value; determining whether said signal is within predetermined limits; impressing a high frequency signal onto a process controlling variable in response to said determination that said controlled variable is within said predetermined limits; measuring the time T1 of impression of said high frequency signal by starting a count; filtering said high frequency signal when received at the process output; measuring the time T2 of filtering by stopping said count; and indicating the interval between the measured times T1 and T2 by sensing said count.

Claim 13

A method for determining the dead time of a regulated process having a controlled and controlling variable so as to update a mathematical model of said process, comprising the steps of: measuring said controlled variable to generate a signal representative of the controlled variable value; determining whether said signal is within predetermined limits; impressing a high frequency signal onto a process controlling variable in response to said determination that said controlled variable is within said predetermined limits; measuring the time T1 of impression of said high frequency signal by starting a count; filtering said high frequency signal when received at the process output; measuring the time T2 of filtering by stopping said count; and indicating the interval between the measured times T1 and T2 by sensing said count.

Claim 14

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a mathematical model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the value of said controlled variable; comparing said first signal to predetermined limits surrounding a set point of said controlled variable and determining that said first signal is within said predetermined limits; impressing a high frequency signal onto said controlling variable at a time T1; storing the value of time T1; filtering out said high frequency signal when received at the output of said process at time T2; storing the value of time T2; and calculating the dead time of said process by subtracting T1 from T2.

Claim 15

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a mathematical model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of the value of said controlled variable; comparing said first signal to predetermined limits surrounding a set point of said controlled variable and determining that said first signal is within said predetermined limits; impressing a high frequency signal onto said controlling variable at a time T1; storing the value of time T1; filtering out said high frequency signal when received at the output of said process at time T2; storing the value of time T2; and calculating the dead time of said process by subtracting T1 from T2.

Claim 16

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a machine-stored mathematical model of that process, said process having a variable dead time due to differences in velocity and distance of a process medium, comprising the steps of: generating a first plurality of electrical signals, each of said signals representing the velocity of said process medium at discrete periods of time; generating a second plurality of electrical signals contemporaneously with said first plurality of electrical signals, each of said second plurality of electrical signals representing the distance of said process medium from a datum point at discrete periods of time; feeding individual ones of said first plurality of signals in a serial fashion and individual ones of said second plurality of signals in a serial fashion to computing apparatus; and calculating the dead time TD of the process according to the equation:

Claim 17

A method for determining the dead time of a process having a controlled variable and a controlling variable so as to update a machine-stored mathematical model of that process, said process having a variable dead time due to differences in velocity and distance of a process medium, comprising the steps of: generating a first plurality of electrical signals, each of said signals representing the velocity of said process medium at discrete periods of time; generating a second plurality of electrical signals contemporaneously with said first plurality of electrical signals, each of said second plurality of electrical signals representing the distance of said process medium from a datum point at discrete periods of time; feeding individual ones of said first plurality of signals in a serial fashion and individual ones of said second plurality of signals in a serial fashion to computing apparatus; and calculating the dead time TD of the process according to the equation:

Claim 18

A method for determining the dead time TD of a process having a controlled variable and a controlling variable so as to update a mathematical model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of said controlled variable; comparing said first signal to predetermined error limits surrounding a set point of said controlled variable and determining whether said first signal is within said predetermined error limits, a second signal representing an average disturbance of said process due to process noise while allowing said process to settle; impressing said second signal on a threshold device, adjusting the threshold level of said threshold device to the level of said second signal; impressing a high frequency signal onto said process and initiating a counting operation in a counter at a time T1; sensing the response of said process and filtering out said high frequency signal from said process response when received at a time T2 by applying a third signal representing said filtered high frequency signal to said threshold device; ceasing said counting opEration at said time T2 by applying the output of said threshold device to said counter; generating a fourth signal quantitatively representing process dead time TD derived from the count of said counter; and updating a model of said process in response to said fourth signal.

Claim 19

A method for determining the dead time TD of a process having a controlled variable and a controlling variable so as to update a mathematical model of that process, comprising the steps of: sensing said controlled variable to generate a first signal representative of said controlled variable; comparing said first signal to predetermined error limits surrounding a set point of said controlled variable and determining whether said first signal is within said predetermined error limits, a second signal representing an average disturbance of said process due to process noise while allowing said process to settle; impressing said second signal on a threshold device, adjusting the threshold level of said threshold device to the level of said second signal; impressing a high frequency signal onto said process and initiating a counting operation in a counter at a time T1; sensing the response of said process and filtering out said high frequency signal from said process response when received at a time T2 by applying a third signal representing said filtered high frequency signal to said threshold device; ceasing said counting opEration at said time T2 by applying the output of said threshold device to said counter; generating a fourth signal quantitatively representing process dead time TD derived from the count of said counter; and updating a model of said process in response to said fourth signal.