Tuning arrangement for turning the control parameters of a controller
AssigneeFisher-Rosemount Systems, Inc.
InventorSheldon G. Lloyd
Life of this patent
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Abstract
A system is provided for tuning at least one control parameter of a controller in a control loop wherein the system includes an oscillation function not in series with the controller for selectively causing the control loop to oscillate at a tuning frequency, while the controller is in control of the process. While oscillating at the tuning frequency, a tuner is responsive to the tuning gain of the control loop and its tuning frequency for determining control parameters for tuning the controller.
Claims21
A system for tuning for at least one control parameter of a controller means, said controller means operating in series with a process in a control loop and controlling said process in response to an error defined as the difference between a process variable and a set point, said system comprising:
- a tuning loop including oscillation causing means and said process, said oscillation causing means being outside of said control loop, said oscillation causing means for selectively causing said control loop to oscillate at a tuning frequency while said controller m is in control of said process, said control loop having a tuning gain while said control loop is oscillating at said tuning frequency;
- and,
- tuning means responsive to said tuning gain and to said tuning frequency for tuning said at least one control parameter.
A system for tuning at least one control parameter of a controller means, said controller means operating in series with a process in a control loop and controlling said process in response to an error defined as the difference between a process variable and a set point, said system comprising:
- nonlinear element means having a nonlinear relay response, said nonlinear elements means arranged to operate in parallel with said controller means for selectively causing said control loop to oscillate at a tuning frequency while said controller means is in control of said process, said control loop having a tuning gain while said control loop is oscillating at said tuning frequency;
- and
- tuning means responsive to said tuning gain and to said tuning frequency for tuning said at least one control parameter.
A system for tuning at least one control parameter of a controller means, said controller means operating in series with a process in a control loop and controlling said process in response to an error between a process variable and a set point, said system comprising:
- nonlinear element means having a nonlinear relay response, said nonlinear element means arranged to operate as a feedback from said process to an input of said controller means for selectively causing said control loop to oscillate at a tuning frequency while said controller means is in control of said process, said control loop having a tuning gain while said control loop is oscillating at said tuning frequency;
- and
- tuning means responsive to said tuning gain and to said tuning frequency for tuning said at least one parameter.
A method for tuning at least one control parameter of a controller means, said controller means operating in series with a process in a control loop and controlling said process in response to an error defined as the difference between a process variable and a set point, said system comprising:
- initiating an oscillation causing means, not in series with said controller means, for selectively causing said control loop to oscillate at a tuning frequency while said controller means is in control of said process, said control loop having a tuning gain while said control loop is oscillating at said tuning frequency;
- and
- activation a tuning means that is responsive to said tuning gain and to said tuning frequency for tuning said at least one control parameter.
Dependencies are inferred from the claim text.