Systems and methods for refrigerant leak management based on acoustic leak detection

Patent metadata

Field	Value
Publication number	US-11573149-B2
Application number	US-201815871682-A
Country	US
Kind code	B2
Filing date	Jan 15, 2018
Priority date	Dec 1, 2017
Publication date	Feb 7, 2023
Grant date	Feb 7, 2023

Abstract

A refrigerant leak management system for a heating, ventilating, and air conditioning (HVAC) system is disclosed. The system includes a controller communicatively coupled to one or more sensors disposed within the HVAC system. The controller measures a vibration pattern associated with a component of the HVAC system. The controller determines whether the vibration pattern is indicative of a refrigerant leak in the HVAC system. Additionally, the controller can modify operation of the HVAC system when the vibration pattern is indicative of the refrigerant leak in the HVAC system.

First claim

The invention claimed is:

1. A refrigerant leak management system, comprising:
a controller communicatively coupled to a sensor disposed on an outer surface of a component within a heating, ventilation, and air conditioning (HVAC) system, wherein the controller is configured to:
measure a vibration pattern corresponding to the component using the sensor, wherein the vibration pattern is measured as an acoustic wave propagating from the outer surface of the component;
determine a probability that the vibration pattern is indicative of a refrigerant leak in the HVAC system; and
modify operation of the HVAC system by:
performing an initial control action in response to the probability being greater than a first threshold value; and
performing an escalated control action in response to the probability being greater than a second threshold value, wherein the second threshold value is greater than the first threshold value.

2. The refrigerant leak management system of claim 1 , wherein, before determining the probability that the vibration pattern is indicative of the refrigerant leak, the controller is configured to:
process the vibration pattern corresponding to the component of the HVAC system via a filter to remove a predetermined vibration pattern associated with normal operation of the component.

3. The refrigerant leak management system of claim 1 , wherein the controller is configured to measure an additional vibration pattern using an additional sensor disposed near the component, and wherein the additional vibration pattern is measured as an additional acoustic wave propagating through air.

4. The refrigerant leak management system of claim 1 , wherein the sensor comprises a microphone.

5. The refrigerant leak management system of claim 1 , wherein the sensor comprises an accelerometer.

6. The refrigerant leak management system of claim 1 , wherein the component comprises a refrigerant conduit of the HVAC system.

7. The refrigerant leak management system of claim 1 , wherein the component comprises an evaporator of the HVAC system.

8. The refrigerant leak management system of claim 1 , wherein the controller is configured to modify the operation of the HVAC system by:
transmitting an alert indicative of the probability that the vibration pattern is indicative of the refrigerant leak, disabling the HVAC system, pumping and confining a refrigerant to a particular portion of a refrigeration circuit of the HVAC system, diluting the refrigerant leak within the HVAC system, or a combination thereof.

9. The refrigerant leak management system of claim 1 , comprising an additional sensor physically coupled to an additional outer surface of the component, and wherein the controller is configured to determine a refrigerant leak position based on respective signals from the sensor and the additional sensor.

10. The refrigerant leak management system of claim 1 , wherein the controller is configured to determine the probability that the vibration pattern is indicative of the refrigerant leak by querying a vibration pattern database to determine whether the vibration pattern corresponds at least in part to a predetermined vibration pattern stored in the vibration pattern database.

11. The refrigerant leak management system of claim 10 , wherein the predetermined vibration pattern stored in the vibration pattern database is based on experimental operations comprising circulating a refrigerant within a test HVAC system that is substantially similar to the HVAC system.

12. The refrigerant leak management system of claim 1 , wherein the controller is configured to apply a filter to the vibration pattern to isolate a target frequency range within the vibration pattern before determining the probability that the vibration pattern is indicative of the refrigerant leak.

13. The refrigerant leak management system of claim 1 , wherein the controller comprises a processor configured to execute a machine learning module, and wherein the controller is configured to:
provide the vibration pattern to the machine learning module; and
receive the probability that the vibration pattern is indicative of the refrigerant leak from the machine learning module.

14. A refrigerant leak management system of a heating, ventilation, and air conditioning (HVAC) system, comprising:
a sensor configured to detect a vibration pattern of an evaporator; and
a controller communicatively coupled to the sensor and configured to:
receive a signal from the sensor indicative of the vibration pattern of the evaporator;
determine, based on the signal, a correspondence between whether the vibration pattern and a reference vibration pattern, wherein the correspondence is indicative of a likelihood of a refrigerant leak from the evaporator; and
modify operation of the HVAC system by:
performing an initial control action in response to the correspondence between the vibration pattern and the reference vibration pattern being greater than a first threshold value; and
performing an escalated control action in response to the correspondence between the vibration pattern and the reference vibration pattern being greater than a second threshold value, wherein the second threshold value is greater than the first threshold value.

15. The refrigerant leak management system of claim 14 , wherein, before determining, based on the signal, the correspondence between whether the vibration pattern and the reference vibration pattern, the controller is configured to:
process the signal indicative of the vibration pattern of the evaporator via a filter to remove a predetermined vibration pattern associated with normal operation of the HVAC system.

16. The refrigerant leak management system of claim 14 , wherein the evaporator comprises a bare tube evaporator, a plate surface evaporator, a finned evaporator, a flooded type evaporator, a dry expansion type evaporator, a forced convection type evaporator, a natural convection type evaporator, or a combination thereof.

17. The refrigerant leak management system of claim 14 , comprising an array of sensors including the sensor, wherein the array of sensors is distributed about the HVAC system, wherein the array of sensors is configured to detect a plurality of vibration patterns including the vibration pattern, and wherein the controller is configured to:
receive a plurality of signals from the array of sensors including the signal from the sensor, the plurality of signals being indicative of the plurality of vibration patterns including the vibration pattern.

18. The refrigerant leak management system of claim 17 , wherein the controller is configured to:
determine a refrigerant leak location based on the plurality of signals; and
modify the operation of the HVAC system based on the refrigerant leak location.

19. A method of operating a refrigerant leak management system of a heating, ventilation, and air conditioning (HVAC) system, comprising:
generating a plurality of vibrations in the HVAC system by routing a refrigerant through the HVAC system;
measuring a plurality of vibration patterns corresponding to the plurality of vibrations using a plurality of sensors disposed near a refrigeration circuit of the HVAC system, wherein the plurality of sensors comprises a sensor disposed on an outer surface of a component of the HVAC system, and wherein the sensor measures a vibration pattern of the plurality of vibration patterns, the vibration pattern corresponding to the component;
determining a probability that the vibration pattern of

Assignees

• Johnson Controls Tech Co
• Johnson Controls Tyco IP Holdings LLP

Inventors

• Gupte Neelkanth
• Walser Jay C
• Perkins James C

Classifications

• F25B2500/222

  Detecting refrigerant leaks · CPC title

• G01M3/16

  using electric detection means ({G01M3/045,} G01M3/06, G01M3/12, G01M3/20, G01M3/24, G01M3/26 take precedence) · CPC title

• G01M3/24 Primary

  using infrasonic, sonic or ultrasonic vibrations · CPC title

• F25B49/005

  of safety devices (F25B49/02 and F25B49/04 take precedence) · CPC title

• F25B2700/00

  Sensing or detecting of parameters; Sensors therefor · CPC title