WO2007046791A1

WO2007046791A1 - Remote diagnostics and prognostics for refrigerant systems

Info

Publication number: WO2007046791A1
Application number: PCT/US2005/037336
Authority: WO
Inventors: Michael F. Taras; Alexander Lifson
Original assignee: Carrier Corporation
Priority date: 2005-10-18
Filing date: 2005-10-18
Publication date: 2007-04-26
Also published as: CN101326415B; CN101326415A; HK1127516A1; EP1946021A4; EP1946021A1; US20090120111A1

Abstract

There is provided a refrigerant system (100) including a plurality of components (120, 125, 140, 145) for regulating operational parameters of the refrigerant system (100), at least one transducer (135) connected to the refrigerant system (100) for monitoring the operational parameters of the refrigerant system (100), and a controller (150). The controller (150) is remotely connected to the at least one transducer (135) and to at least one component (120, 125, 140, 145) of the plurality of components (120, 125, 140, 145) for at least periodically receiving parameter information from the at least one transducer (135) to monitor the operational parameters and determine, based on variations in at least one parameter of the operational parameters, whether a condition exists in the refrigerant system (100) that requires corrective action. The corrective action may include moving the refrigerant system (100) to a lighter mode of operation by unloading or even shutting down some of the refrigerant system components (120, 125, 140, 145). There is also provided a method for monitoring the refrigerant system (100).

Description

REMOTE DIAGNOSTICS AND PROGNOSTICS FOR REFRIGERANT

SYSTEMS

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to diagnostic systems and methods, and more particularly, to diagnostic systems and methods in refrigerant systems established via a remote connection.

2. Description of the Related Art

While complexity of refrigerant systems is continuously increasing, troubleshooting and maintenance (both required and preventive) have become extremely time-consuming and expensive. These activities are closely related to the need for reliable diagnostic and prognostic techniques. Nowadays, most troubleshooting and maintenance are performed by technicians or mechanics on a job site and frequently require a number of iterations, since the root cause of a problem is not known prior to their visits. Furthermore, preventive maintenance intervals, although representing good business practice, may not need to be performed as often as scheduled, and their frequency ideally should vary in accordance with application severity and operation environment harshness.

Therefore, there is a need for a diagnostic and prognostic system and method that will increase efficiency of troubleshooting and maintenance, and consequently reduce troubleshooting and maintenance expense as well as refrigerant equipment downtime and customer discomfort. SUMMARY OF THE INVENTION

There is provided a refrigerant system including a plurality of components for regulating operational parameters of the refrigerant system, at least one transducer connected to the refrigerant system for monitoring the operational parameters of the refrigerant system, and a controller. The controller is remotely connected to the at least one transducer and to at least one component of the plurality of components, for at least periodically receiving operational parameter information from the at least one transducer to monitor the operational parameters and determine, based on variations in at least one parameter of the operational parameters, whether a condition exists in the refrigerant system that requires corrective action.

In one embodiment, the controller is remotely connected to the at least one transducer and at least one component of the refrigerant system via a local system controller. The controller controls said local system controller to monitor and operate the refrigerant system.

There is also provided a method for monitoring a refrigerant system. The method includes detecting operational parameters of the refrigerant system at least periodically, and during an operation of the refrigerant system, via at least one transducer connected to the refrigerant system. The method further includes receiving parameter information from the at least one transducer to monitor the operational parameters via a controller remotely connected to the at least one transducer and at least one component of a plurality of components. The method also includes determining, based on variations in at least one parameter of the operational parameters, whether a condition exists in the refrigerant system that requires corrective action. BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 shows a refrigerant system including a monitoring system according to the present invention.

DESCRIPTION OF THE INVENTION

Figure 1 shows a refrigerant system 100 including a monitoring system 105 according to the present invention. Refrigerant system 100 includes refrigerant lines 110, and a plurality of components for regulating operational parameters of refrigerant system 100, including condenser and evaporator heat exchangers 115 associated with corresponding outdoor and indoor fans 145, expansion device 120, compressor 125, and discharge, suction and bypass flow control devices such as valves 140. The schematic presented in Figure 1 is purely exemplary; there are many possible configurations and variations of the design of refrigerant system 100 that are not shown but fall within the scope of the invention.

Monitoring system 105 includes a remote controller 150, connected to refrigerant system 100. Controller 150 is connected to transducers 135 and to at least one of the plurality of components including fans 145, expansion device, e.g., valve 120, compressor 125, and valves 140. Transducers 135 may be temperature or pressure transducers, and are connected to refrigerant system 100 at various location points, for example, at lines 110 for simplicity of installation. In one embodiment, remote controller 150 is indirectly connected to refrigerant system 100 via an optional local system controller 130, which is directly connected to transducers 135 and to at least one of the plurality of components. In one embodiment, remote controller 150 is connected to transducers 135, for monitoring refrigerant system 100, and to at least compressor 125 and/or valves 140. Remote controller 150 receives signals from transducers 135, translates the signals into parameter information, and controls components of refrigerant system 100 and monitoring system 105, such as transducers 135, compressor 125 and valves 140. Remote controller 150 may also provide information to a user regarding observed parameters and the status of various components.

Remote controller 150 preferably includes a computing platform, such as a personal computer, a mainframe computer, or any other type of computing platform that may be provisioned with a memory device (not shown), a CPU or microprocessor device (not shown), and several I/O ports (not shown). Remote controller 150 may also include a display or other device for providing information, a visual or audio indicator to identify a malfunctioning component. Remote controller 150 may also include an interface allowing a user to set operating parameters and control components of refrigerant system 100 and/or monitoring system 105.

Remote controller 150 is remotely connected to refrigerant system

100. In one embodiment, remote controller 150 is connected to transducers 135, compressor 125, and/or other components of refrigerant system 100. Controller may be directly connected to refrigerant system 100 over a remote connection or a network, such as the Internet, an intranet, or a local area network. In another embodiment, remote controller 150 is remotely connected to refrigerant system 100 via local system controller 130, which is directly connected to transducers 135 and other components of refrigerant system 100.

In another embodiment, local system controller 130 is directly connected to transducers 135, compressor 125, and/or other components of refrigerant system 100. Local system controller 130 may be hard wired to the system components. Remote controller 150 is connected to local system controller 130 over a remote connection or a network, such as the Internet, an Intranet, or a local area network. In this embodiment, remote controller 150 operates local system controller 130 to monitor and control refrigerant system 100.

Remote controller 150 collects and processes operational parameter information of refrigerant system 100 in real time, preferably during normal operation of refrigerant system 100, for diagnosis and/or prognosis of potentially malfunctioning or degrading components of refrigerant system 100. Remote controller 150 collects parameter information by receiving signals from at least one of transducers 135, to monitor said operational parameters, and determines whether a condition exists in said refrigerant system that requires corrective action. In one embodiment, remote controller 150 receives parameter information form transducers 135 via focal system controller 130. Remote controller 150 determines whether a condition requiring corrective action exists based on variations in at least one parameter of said operational parameters. Remote controller 150 collects parameter information periodically or when problems arise. Remote controller 150 may also collect parameter information from transducers 135 continuously during operation of refrigerant system 100.

Remote controller 150 performs a diagnostic function by determining whether a condition exists that requires corrective action. In one embodiment, remote controller 150 displays parameter information to a user, who then determines whether a condition requiring corrective action exists. Such a condition may be a potential malfunction of one or more of the components, such as valves 140, and/or a degradation of the operation of refrigerant system 100 caused by one or more of said components. Remote controller 150 may determine whether a component is malfunctioning, or potentially malfunctioning, by remotely switching at least one of the components from a first operating state to a second operating state, observing a variation in an operational parameter resulting from the switching, comparing the observed variation with an expected variation due to the switching, and detecting a difference or a substantial difference between the observed variation and the expected variation. In one embodiment, a tolerance value, or minimum difference between the observed variation and the expected variation can be set, so that any difference greater than the tolerance value will trigger a malfunction determination.

In the instance of valve components, remote controller 150 switches valves such as valves 120 and 140 between operating positions, such as "on", i.e., open, or "off, i.e., closed. The operating position of valves 120 and 140 may also be an intermediate position between "on" and "off' positions. A first operating state is a first position of valves 120 and 140, and a second operating state is a second position of valves 120 and 140. For example, valves 120 and 140 can be tested by moving them from a first operating state to a second operating state for a short period of time during startup, shutdown or continuous operation and monitoring the change in the corresponding operational parameters.

Remote controller 150 may detect a degradation of operation of refrigerant system 100 by remotely observing a change in related operational parameters over a period of time. Examples of components that could cause degradation include air filters, which can become dirty or clogged, and condenser/evaporator coils 115, which can become clogged, rusted or accidentally blocked. In this embodiment, the system is a prognostic system, because although there is no actual malfunction, the degradation in operational parameters indicates that a problem is developing. The system can then generate a response to address such a developing problem before it detrimentally affects reliability of refrigerant system 100 or significantly affects its operation. For instance, refrigerant system 100 may be moved by remote controller 150 to a lighter (less loaded) mode of operation to prevent component breakdown or failure.

In circumstances where operation of refrigerant system 100 is monitored over a prolonged period of time, prognostic methodology can be employed. Degradation of operational parameters can be monitored over a period of time, so that predictions can be made with high confidence as to when preventive maintenance must be performed for a particular system installation.

When remote controller 150 determines that a condition requiring corrective action exists, remote controller 150 may generate a response. The response may include generating a warning signal indicating that the condition exists. The warning signal may be displayed to an end user. The response may also include generating a repair or maintenance request, which can be relayed to a repair center or other location by which a repair technician is alerted. The signal and the repair or maintenance request include an identification of one or more of the components that are causing said condition. Thus, information regarding the root cause of a malfunction accompanies the repair request, allowing a technician to more efficiently address the malfunction and thus more quickly complete repairs.

In another embodiment, the response includes remotely controlling at least one of the components to alter the operational parameters to remedy the condition and/or avoid further damage to refrigerant system 100. On some occasions, for example, when a condition requiring corrective action exists but the condition cannot be addressed or a technician cannot get to the unit in a reasonable time, remote controller 150 can control at least one of the components to operate refrigerant system 100 in a light mode, i.e., a lighter or less loaded mode of operation, while providing continuous monitoring of its operation. In this instance, remote controller 150 performs sequential unloading steps. For example, if a potential problem is associated with compressor 125, then remote controller 150 can run refrigerant system 100 in the bypass mode or at reduced speed. In another example, if the problem is associated with one of fans 145, remote controller 150 can reduce the speed of one or more of the fans 145. This will prevent refrigerant system 100 downtime and will provide some, although potentially reduced, comfort to the end user. If a sequence of lighter modes of operation proves insufficient to reduce or temporarily eliminate the condition or malfunction, remote controller 150 can shut down one or more of the components and/or shut down refrigerant system 100 completely. Shutting down refrigerant system 100 completely should be a last resort and when all other possible measures are exhausted.

The method for monitoring a refrigerant system includes detecting operational parameters of refrigerant system 100 at least periodically and during an operation of refrigerant system 100, receiving parameter information from at least one transducer 135 via remote controller 150, and determining, based on variations in at least one operational parameter, whether a condition exists in refrigerant system 100 that requires corrective action.

In another embodiment, the operational parameters are continuously detected and parameter information is continuously received. In yet another embodiment, the step of determining whether the potential malfunction, i.e., condition requiring corrective action, exists includes switching at least one component of the plurality of components from a first operating state to a second operating state, observing a variation in an operational parameter resulting from the switching, comparing the observed variation with an expected variation due to the switching, and detecting a substantial difference between the observed variation and the expected variation. In yet another embodiment, the step of determining whether the degradation exists includes detecting degradation in the operational parameters over a period of time.

In still another embodiment, the method includes generating a response if the condition exists. The response may include generating a signal indicating that the condition exists, generating a repair or maintenance request, and/or remotely controlling at least one of the plurality of components to alter operational parameters to remedy the condition and/or avoid further damage to refrigerant system 100. In still another embodiment, the signal and the repair or maintenance request include an identification of one or more of the plurality of components that are causing the condition.

In another embodiment, controlling at least one of the plurality of components includes operating refrigerant system 100 in a light mode (e.g., unloaded mode), shutting down one or more of the plurality of components, and/or shutting down refrigerant system 100.

Thus, in a number of circumstances, the system and method of the present invention will significantly reduce the expense of troubleshooting and maintenance as well as refrigerant system downtime and customer discomfort. The system and method has an additional advantage in that it requires only control logic modifications and requires no hardware change or addition.

It should be understood that various alternatives, combinations and modifications of the teachings described herein could be devised by those skilled in the art. The present invention is intended to embrace all such alternatives, modifications and variances that fall within the scope of the appended claims.

Claims

WHAT IS CLAIMED IS:

1. A method for monitoring a refrigerant system 100, comprising the steps of:

detecting operational parameters of said refrigerant system 100 at least periodically, and during an operation of said refrigerant system 100, via at least one transducer 135 connected to said refrigerant system 100;

receiving parameter information, to monitor said operational parameters, from said at least one transducer 135 via a controller 150 remotely connected to said at least one transducer 135 and to at least one component 120, 125, 140, 145 of a plurality of components 120, 125, 140, 145; and

determining, based on variations in at least one parameter of said operational parameters, whether a condition exists in said refrigerant system 100 that requires corrective action.

2. The method of claim 1 , wherein controller 150 is remotely connected to said at least one transducer 135 via a local system controller 130, and wherein said controller 150 controls said local system controller to operate and monitor said refrigerant system 100.

3. The method of claim 1 , wherein said controller 150 is connected to said at least one transducer 135 through the Internet.

4. The method of claim 1 , wherein said operational parameters are continuously detected and parameter information is continuously received.

5. The method of claim 1 , wherein said condition is selected from the group consisting of the following:

a potential malfunction of one or more of said components 120, 125, 140, 145

a degradation of system operation caused by one or more of said components 120, 125, 140, 145, and

a combination thereof.

6. The method of claim 5, wherein said step of determining whether said potential malfunction exists includes switching at least one component 120, 140, 145 of said plurality of components 120, 125, 140, 145 from a first operating state to a second operating state, observing a variation in an operational parameter resulting from said switching, comparing said observed variation with an expected variation due to said switching, and detecting a substantial difference between said observed variation and said expected variation.

7. The method of claim 5, wherein said step of determining whether said degradation exists includes detecting degradation in said operational parameters over a period of time.

8. The method of claim 1 , comprising the further step of generating a response if said condition exists, wherein said response is selected from the group consisting of:

generating a signal indicating that said condition exists,

generating a repair or maintenance request, remotely controlling at least one of said plurality of components 120, 125, 140, 145 to alter operational parameters to perform at least one of a function selected from the group consisting of remedying said condition and avoiding further damage to said refrigerant system, and

any combinations thereof.

9. The method of claim 8, wherein said signal and said repair or maintenance request include an identification of one or more of said plurality of components 120, 125, 140, 145 that are causing said condition.

10. The method of claim 8, wherein said controlling at least one of said plurality of components 120, 125, 140, 145 includes at least one action selected from the group consisting of.

operating said refrigerant system 100 in a light mode,

shutting down one or more of said plurality of components 120, 125, 140, 145, and

shutting down said refrigerant system 100.

11. A refrigerant system comprising:

a plurality of components 120, 125, 140, 145 for regulating operational parameters of said refrigerant system;

at least one transducer 135 connected to said refrigerant system 100 for monitoring said operational parameters of said refrigerant system 100; a controller 150 remotely connected to said at least one transducer 135 and to at least one component 120, 125, 140, 145 of said plurality of components 120, 125, 140, 145 for at least periodically receiving parameter information from said at least one transducer 135 to monitor said operational parameters and determine, based on variations in at least one parameter of said operational parameters, whether a condition exists in said refrigerant system 100 that requires corrective action.

12. The system of claim 11 , wherein controller 150 is remotely connected to said at least one transducer 135 via a local system controller 130, and wherein said controller 150 controls said local system controller to operate and monitor said refrigerant system 100.

13. The system of claim 11 , wherein said controller 150 is connected to said at least one transducer 135 through the Internet.

14. The system of claim 11, wherein said condition is selected from the group consisting of the following:

a potential malfunction of one or more of said components 120, 125, 140, 145,

a degradation of refrigerant system 100 operation caused by one or more of said components 120, 125, 140, 145, and

a combination thereof.

15. The system of claim 14, wherein said controller 150 detects a potential malfunction by switching at least one component 120, 140, 145 of said plurality of components 120, 125, 140, 145 from a first operating state to a second operating state, observing a variation in an operational parameter resulting from said switching, comparing said observed variation with an expected variation due to said switching, and detecting a substantial difference between said observed variation and said expected variation.

16. The system of claim 14, wherein said controller 150 detects a degradation of system operation by detecting degradation in said operational parameters over a period of time.

17. The system of claim 11 , wherein said controller 150 generates a response if said condition exists, wherein said response is selected from the group consisting of:

generating a signal indicating that said condition exists,

generating a repair or maintenance request,

remotely controlling at least one of said plurality of components 120, 125, 140, 145 to alter said operational parameters to perform at least one of a function selected from the group consisting of remedying said condition and avoiding further damage to said refrigerant system,

and any combinations thereof.

18. The system of claim 17, wherein said signal and said repair or maintenance request include an identification of one or more of said plurality of components 120, 125, 140, 145 that are causing said condition.

19. The system of claim 17, wherein said controlling at least one of said plurality of components 120, 125, 140, 145 includes at least one action selected from the group consisting of:

operating said refrigerant system 100 in a light mode,

shutting down said refrigerant system 100.

20. A refrigerant system or method for monitoring a refrigerant system as herein before described with reference to Figure 1 of the accompanying drawings.