SYSTEM AND METHOD FOR DETECTING DETERIORATION OF A CONTROL VALVE

• US 20200131927A1
• Filed: 04/18/2018
• Published: 04/30/2020
• Est. Priority Date: 04/21/2017
• Status: Active Grant

• Current Assignee: Compressor Controls LLC (Honeywell International Inc.)
• Original Assignee: Compressor Controls Corporation (Roper Technologies, Inc.)
• Inventors: Tolmatsky, Michael Lev, Staroselsky, Serge, Negley, Paul Marvin, Tse, John
• Granted Patent: US 11,613,999 B2
• Time in Patent Office: Days
• CPC Class Codes: F01D 21/14 responsive to other specific conditions
• CPC Class Codes: F04D 27/001 Testing thereof; Determination or simulation of flow characteristics; Stall or surge detection, e.g. condition monitoring
• CPC Class Codes: F04D 27/008 Stop safety or alarm devices, e.g. stop-and-go control; Disposition of check-valves
• CPC Class Codes: F04D 27/0215 Arrangements therefor, e.g. bleed or by-pass valves
• CPC Class Codes: F05D 2260/80 Diagnostics
• CPC Class Codes: F16K 37/0041 for measuring valve parameters F16K37/0033 takes precedence
• CPC Class Codes: F16K 37/0083 by measuring valve parameters
• CPC Class Codes: F16K 37/0091 by measuring fluid parameters
• CPC Class Codes: G01M 13/003 Machine valves testing valves for fluid tightness G01M3/00

Abstract

Automatic testing for control valves is provided for diagnosing of actuators, including actuators not equipped with analog or discrete position transmitters. A valve controller confirms steady-state conditions for a turbo-compressor system that includes a control valve in a first position and sends, to an actuator for the control valve, a signal to initiate a partial valve stroke to move the control valve away from the first position. The valve controller receives feedback signals from sensors in the turbo-compressor system and monitors the feedback signals for a change from the steady-state conditions. When the monitoring detects a change from the steady-state conditions within a defined time period, the valve controller sends, to the actuator, a signal to return the control valve to the first position. When the monitoring does not detect a change from the steady-state conditions within the defined time period, the valve controller generates an alarm signal.

Claims

1. A method of conducting a diagnostic test for a control valve, the method comprising:

confirming, by a control system, steady-state conditions for a turbo-compressor system that includes the control valve in a first position;

sending, by the control system and to an actuator for the control valve, a signal to initiate a partial valve stroke to move the control valve away from the first position;

receiving, by the control system and after sending the signal to initiate the partial valve stroke, feedback signals from sensors in the turbo-compressor system;

monitoring, by the control system, the feedback signals for a change from the steady-state conditions;

sending, by the control system and to the actuator, a signal to return the control valve to the first position in response to the monitoring detecting a change from the steady-state conditions within a defined time period; and

generating, by the control system, an alarm signal in response to the monitoring not detecting a change from the steady-state conditions within the defined time period.

2. The method of claim 1, wherein confirming the steady-state conditions includes receiving multiple feedback signals from different sources.

3. The method of claim 2, wherein the multiple feedback signals include signals from one or more pressure sensors or one or more flow sensors, or variables calculated based on one or more of the multiple feedback signals.

4. The method of claim 3, wherein the multiple feedback signals further include a valve position signal.

5. The method of claim 1, wherein sending the signal to initiate the partial valve stroke includes sending instructions for a ramped valve movement, the instructions including a target valve movement distance and ramp rate.

6. The method of claim 1, wherein sending the signal to initiate the partial valve stroke includes sending instructions for a step valve movement, the instructions including a step size for the valve movement that is less than a full valve stroke.

7. The method of claim 1, wherein sending the signal to initiate the partial valve stroke includes sending instructions for a multi-step valve movement, the instructions including a step size, a number of steps, and a time interval between steps.

8. The method of claim 1, wherein sending the signal to initiate the partial valve stroke includes sending instructions for one or more of a ramped valve movement or a step valve movement.

9. The method of claim 1, wherein monitoring the feedback signals for the change from the steady-state conditions further comprises:

monitoring a differential for the feedback signals over different time intervals, and

comparing derivatives calculated using each of the different time intervals to a steady-state threshold.

10. The method of claim 9, wherein the different time intervals include more than one different time intervals.

11. The method of claim 1, wherein the signal to initiate the partial valve stroke to move the control valve away from the first position includes a second position with a maximum allowed distance that is configured to disrupt the steady-state conditions without disabling the turbo-compressor system.

12. The method of claim 1, further comprising:

receiving, by the control system, a signal to initiate the diagnostic test, wherein the signal to initiate the diagnostic test is one of a manual start command or a periodic test command.

13. A valve control system, comprising:

a memory device for storing instructions; and

a processor configured to execute the instructions to;

confirm steady-state conditions for a turbo-compressor system that includes a control valve in a first position;

send, to an actuator for the control valve, a signal to initiate a partial valve stroke to move the control valve away from the first position;

receive, after sending the signal to initiate the partial valve stroke, feedback signals from sensors in the turbo-compressor system;

monitor the feedback signals for a change from the steady-state conditions;

send, to the actuator, a signal to return the control valve to the first position in response to the monitoring detecting a change from the steady-state conditions within a defined time period; and

generate an alarm signal in response to the monitoring not detecting a change from the steady-state conditions within the defined time period.

14. The valve control system of claim 13, wherein, when monitoring the feedback signals for the change from the steady-state conditions, the processor is further configured to:

monitor a derivative for the feedback signals over different time intervals, and

compare each of the derivatives to a steady-state threshold.

15. The valve control system of claim 14, wherein the different time intervals include more than one and up to five different time intervals.

16. The valve control system of claim 14, wherein the steady-state threshold represents a minimum amount of change required to indicate a disturbance from the steady-state conditions.

17. The valve control system of claim 13, wherein, when confirming steady-state conditions, the processor is further configured to:

monitor feedback signals for one or more of suction pressure, discharge pressure, or flow rate.

18. The valve control system of claim 13, wherein the feedback signals include feedback signals from at least one sensor.

19. A non-transitory computer-readable medium containing instructions executable by at least one processor, the computer-readable medium comprising one or more instructions to:

confirm steady-state conditions for a turbo-compressor system that includes a control valve in a first position;

send, to an actuator for the control valve, a signal to initiate a partial valve stroke to move the control valve away from the first position;

receive, after sending the signal to initiate the partial valve stroke, feedback signals from sensors in the turbo-compressor system;

monitor the feedback signals for a change from the steady-state conditions;

send, to the actuator, a signal to return the control valve to the first position in response to the monitoring detecting a change from the steady-state conditions within a defined time period; and

generate an alarm signal in response to the monitoring not detecting a change from the steady-state conditions within the defined time period.

20. The non-transitory computer-readable medium claim 19, further comprising one or more instructions to:

receive a signal to initiate a diagnostic exercise, wherein confirming the steady-state conditions is performed in response to receiving the signal to initiate the diagnostic exercise.