Control system with response time estimation and automatic operating parameter adjustment

1. A control system for a plant, the control system comprising:

a controller configured to estimate a response time of the plant and adjust a sampling rate based on the estimated response time, wherein the response time is a parameter that characterizes a response of the plant to a disturbance; and

a sensor configured to receive the adjusted sampling rate from the controller, collect samples of a measured variable from the plant at the adjusted sampling rate, and provide the samples of the measured variable to the controller;

wherein the controller is configured to detect the disturbance in the control system, evaluate a signal affected by the disturbance to estimate the response time of the plant, classify the disturbance as either a setpoint change or a load disturbance and, if the disturbance is classified as a setpoint change, the controller is configured to estimate the response time by:

identifying a portion of the signal affected by the disturbance;

tracking an area bounded by the identified portion of the signal; and

dividing the area bounded by the identified portion of the signal by a magnitude of the setpoint change to determine the estimated response time.

2. The control system of claim 1 , wherein the controller is configured to use the samples of the measured variable to generate and provide an input to the plant.

3. The control system of claim 1 , wherein the controller is configured to use the adjusted sampling rate to generate samples of the signal affected by the disturbance.

4. The control system of claim 1 , wherein the signal affected by the disturbance comprises at least one of the measured variable and a function of the measured variable.

5. The control system of claim 1 , wherein the signal affected by the disturbance comprises at least one of an input provided to the plant and a function of the input provided to the plant.

6. The control system of claim 1 , wherein the response time comprises at least one of a dominant time constant, a bandwidth, and an open loop response time of the plant.

7. A method for monitoring and controlling a plant, the method comprising:

receiving, at a controller for the plant, a signal affected by a disturbance in a control system for the plant;

classifying the disturbance as either a setpoint change or a load disturbance;

evaluating the signal affected by the disturbance to estimate a response time of the plant, wherein the response time is a parameter that characterizes a response of the plant to the disturbance and, if the disturbance is classified as a setpoint change, estimating the response time comprises:

identifying a portion of the signal affected by the disturbance,

tracking an area bounded by the identified portion of the signal; and

dividing the area bounded by the identified portion of the signal by a magnitude of the setpoint change to determine the estimated response time;

adjusting a sampling rate based on the estimated response time;

providing the adjusted sampling rate from the controller to a sensor;

using the sensor to collect samples of a measured variable from the plant at the adjusted sampling rate; and

using the samples of the measured variable to generate and provide an input to the plant.

8. The method of claim 7 , further comprising detecting the disturbance in the control system for the plant;

wherein the signal affected by the disturbance is evaluated in response to detecting the disturbance.

9. The method of claim 7 , further comprising using the adjusted sampling rate to generate samples of the signal affected by the disturbance.

10. The method of claim 7 , wherein the signal affected by the disturbance comprises at least one of the measured variable and a function of the measured variable.

11. The method of claim 7 , wherein the signal affected by the disturbance comprises at least one of the input provided to the plant and a function of the input provided to the plant.

12. The method of claim 7 , wherein the response time comprises at least one of a dominant time constant, a bandwidth, and an open loop response time of the plant.

13. A control system for a plant, the control system comprising:

a disturbance detector configured to detect a disturbance in the control system and classify the disturbance as either a setpoint change or a load disturbance;

a response time estimator configured to evaluate a signal affected by the disturbance to estimate a response time of a plant, wherein the response time is a parameter that characterizes a response of the plant to the disturbance and, if the disturbance is classified as a setpoint change, the response time estimator is configured to estimate the response time by:

identifying a portion of the signal affected by the disturbance;

tracking an area bounded by the identified portion of the signal; and

dividing the area bounded by the identified portion of the signal by a magnitude of the setpoint change to determine the estimate response time;

a fault detector configured to detect a fault in the control system based on the estimated response time of the plant; and

an adaptive controller configured to generate and provide an input to the plant.

14. The control system of claim 13 , wherein the fault detector is configured to detect the fault by:

comparing the estimated response time to a previous response time for the plant; and

determining that a fault has occurred in response to the estimated response time deviating from the previous response time by a predetermined amount.

15. The control system of claim 13 , further comprising an operating parameter calculator configured to adjust an operating parameter used by the adaptive controller based on the estimated response time.

16. The control system of claim 15 , wherein the adjusted operating parameter comprises at least one of a controller gain and an integral time.

17. The control system of claim 13 , further comprising a sampling rate adjustor configured to adjust a sampling rate based on the estimated response time.

18. The control system of claim 17 , further comprising a sensor configured to:

collect samples of a measured variable from the plant at the adjusted sampling rate; and

provide the samples of the measured variable to the adaptive controller.

19. The control system of claim 13 , wherein the response time comprises at least one of a dominant time constant, a bandwidth, and an open loop response time of the plant.