Method for detecting leaks, control device and cooling system

Abstract

A method, a control device, and a cooling system for detecting leaks in a cooling system including a plurality of cooling units are provided. The method includes adjusting operation of a first cooling unit of the plurality of cooling units. The method further includes determining at least one parameter of the first cooling unit when the first cooling unit is operating according to the adjusted operation, and operating at least one other cooling unit of the plurality of cooling units to compensate for the adjusted operation of the first cooling unit. The method further includes comparing the at least one parameter to a reference value.

Description

Technical Field

[0001] The present disclosure relates to a method for detecting leaks in a cooling system, a control device, and a cooling system. Background Art

[0002] In data centers, servers and other computing equipment generate significant amounts of heat and often require cooling to prevent overheating. This is important because many industries rely on data centers to operate reliably and without interruption. For example, data centers may serve as part of critical infrastructure at airports, banks, and hospitals, where even brief interruptions are unacceptable. Therefore, it's essential for data centers to maintain efficiency, guarantee data integrity, and maintain customer trust by providing continuous operation. In data centers, as well as other environments, cooling systems remove excess heat from the air to cool it. This helps condition the environment in which the servers reside and, therefore, helps maintain their continuous, efficient operation.

[0003] To prevent failures and ensure continuous data center operation, data centers may include numerous redundant components, such as multiple power distribution units, power supplies, and cooling delivery units. This redundancy acts as a buffer in the event of planned or unplanned maintenance on one of these components. Consequently, cooling systems may include multiple cooling units. This further ensures uninterrupted data center operation.

[0004] One malfunction that can lead to interrupted operation or reduced efficiency of the cooling unit is refrigerant leakage from the cooling unit. This can be due, for example, to welding defects, material fatigue due to mechanical stress (vibration), mechanical or chemical damage to the refrigerant circuit, and / or damage to gaskets due to thermal fluctuations.

[0005] Refrigerant leaks are undesirable for several reasons. Refrigerant is expensive and cooling units require a certain amount of refrigerant to operate properly, so it is desirable to avoid the need to replace lost refrigerant. In addition, the loss of refrigerant may have a negative impact on components of the cooling unit, such as the compressor, which may result in the need to replace or repair such components. In addition, using smaller amounts of refrigerant improves the energy efficiency ratio (EER) of the cooling unit. With a large leak, the cooling unit will lose its ability to operate properly and will not be able to provide the cooling effect it was designed for, which may introduce unnecessary downtime in the data center. Service calls to repair / refill the cooling unit will result in additional downtime. In addition, lost refrigerant has a non-zero global warming potential (GWP), so undetected leaks introduce more greenhouse gases into the atmosphere and reduce the sustainability of the data center. Refrigerant can be flammable, so leaks can also cause safety issues.

[0006] Leak detection can be performed in a direct or indirect manner. Direct leak detection is usually performed using a specially manufactured and calibrated sensor (called a "sniffer") that can detect the presence of refrigerant in the air. However, such sniffers have a number of problems. Sniffers only work properly in enclosed spaces with minimal air flow and are not suitable for use in external / outdoor environments (where the condenser or an entire unit such as a chiller may be located). Even if there is a leak in the connecting line between the indoor unit and the outdoor unit, the sniffer cannot detect the leak. A sniffer can only detect a leak if the leak occurs relatively close to the sniffer. In addition, the sniffer cannot determine which cooling unit or circuit is leaking, only that refrigerant is leaking from somewhere. In addition, sniffers are expensive and need to be calibrated and replaced regularly.

[0007] Indirect leak detection can be performed by measuring abnormal system performance of cooling units. However, it can be difficult to determine whether a cooling unit's performance is "abnormal" based on these measurements. In order to make meaningful comparisons and draw conclusions, it may be necessary to modify the cooling unit's operating procedures. This often results in altering the cooling provided by the cooling unit, unnecessarily impacting the operation of the data center's computing equipment. Therefore, there's a trade-off between continuing to operate the cooling unit to provide the desired cooling and performing leak detection or maintenance on the cooling unit.

[0008] It would be desirable to be able to detect refrigerant leaks more quickly, before the operation of a cooling unit is significantly reduced, leading to unnecessary downtime. It would also be desirable to more reliably determine which cooling unit is leaking, further increasing the speed at which the leak's specific location can be detected and avoiding the need to shut down multiple cooling units to inspect each one. It would also be desirable to more accurately detect leaks without negatively impacting the operation of the cooling components. Therefore, it would be desirable to use a cooling system that provides more reliable cooling.

[0009] The present invention is directed to addressing these and other shortcomings encountered in the prior art. Summary of the Invention

[0010] According to one aspect, a method for detecting a leak in a cooling system comprising a plurality of cooling units is provided, the method comprising: adjusting operation of a first cooling unit among the plurality of cooling units; when the first cooling unit operates according to the adjusted operation: determining at least one parameter of the first cooling unit; and operating at least one other cooling unit among the plurality of cooling units to compensate for the adjusted operation of the first cooling unit; and comparing the at least one parameter with a reference value.

[0011] According to another aspect, a control device is provided. The control device includes a processor and a memory. The memory stores computer-executable instructions. When the instructions are executed, the processor performs the above method.

[0012] According to another aspect, a cooling system is provided, comprising: the aforementioned control device and the aforementioned plurality of cooling units. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Detailed description will now be described, by way of example only, with reference to the accompanying drawings, in which:

[0014] Figure 1 depicts an example cooling unit according to the present disclosure;

[0015] Figure 2 depicts an example cooling system according to the present disclosure;

[0016] Figure 3 Depicted are example methods for detecting leaks according to the present disclosure;

[0017] Figure 4 depicts another example cooling unit according to the present disclosure;

[0018] Figure 5 depicts another example cooling unit according to the present disclosure;

[0019] Figure 6 depicts another example cooling unit according to the present disclosure;

[0020] Figure 7a and Figure 7b A speculum according to the present disclosure is depicted;

[0021] Figure 8 depicts another example cooling unit according to the present disclosure;

[0022] Figure 9 depicts another example cooling unit according to the present disclosure;

[0023] Figure 10 An example computing device according to the present disclosure is depicted. DETAILED DESCRIPTION

[0024] The present disclosure provides a technique for detecting leaks in a cooling system comprising multiple cooling units. The operation of a first cooling unit among the multiple cooling units is adjusted. When the first cooling unit operates in the adjusted manner, at least one parameter of the first cooling unit is determined. Furthermore, when the first cooling unit operates in the adjusted manner, one or more other cooling units among the multiple cooling units are operated to compensate for the adjusted operation of the first cooling unit. The at least one parameter is compared to a reference value. A difference between the at least one parameter and the reference value may indicate the presence of a leak.

[0025] These techniques provide a non-invasive method for determining whether a cooling unit is leaking. These techniques can determine which cooling unit is leaking (i.e., the cooling unit for which at least one parameter is determined). In addition, because the determination is made by comparing the at least one parameter with a reference value, leak detection can be performed in a quantitative and accurate manner. Moreover, because the remaining cooling units of the cooling system can cover the required cooling capacity as a whole, the impact on cooling components such as servers in a data center is negligible. Therefore, the technology of the present disclosure can use cooling units more reliably and efficiently by providing improved leak detection, without reducing the cooling capacity provided at any particular moment.

[0026] Figure 1 An example of a cooling unit 100 according to the present disclosure is depicted. A cooling unit (which may also be referred to as a cooling transport unit) is configured to absorb heat (e.g., heat generated by a server) from a given space and transfer it outside of that space, e.g., to the external environment where the heat is released. The techniques of the present disclosure are applicable to all cooling units and cooling systems. For ease of illustration, Figure 1 The cooling unit 100 may be an air handling unit having one circuit, but the technology of the present disclosure is not limited thereto.

[0027] The cooling unit 100 can be divided into two parts, which can be referred to as an air circuit and a refrigerant circuit. The air circuit is configured to move hot air by drawing it from the servers into the cooling unit 100 and supplying the same air at a lower temperature back to the servers. This can be done using fans. Figure 1 Air is represented by a series of adjacent vertical arrows pointing up and down. Figure 1In the embodiment of the present invention, the refrigerant passes in a generally clockwise direction in one or more pipes or conduits, which are represented by a series of arrows arranged in a circle / rectangle. This can be referred to as a refrigerant circuit. The refrigerant circuit is configured to circulate the refrigerant to cool the air of the air circuit. The refrigerant used in the refrigerant circuit can be water, a water-glycol mixture, a fluorinated gas (F-gas) or a natural gas, such as carbon dioxide or propane. As understood by those skilled in the art, the refrigerant can be a mixture of gases, such as R410A or R1234ze. For ease of understanding, the following will focus on phase change refrigerants, but the present disclosure is not limited thereto.

[0028] The refrigerant circuit is a closed loop in which the same refrigerant circulates while changing its physical properties, such as pressure, temperature, and state (liquid or gas). The evaporator fan 102 is configured to move hot air from one or more servers and their surroundings to the evaporator coil 104 (also referred to herein as the evaporator). The hot air passes through the evaporator 104 and cools down as the refrigerant absorbs heat. This occurs without mixing the air and refrigerant. The cooler air can then be recirculated to the one or more servers to absorb more heat.

[0029] During the heat absorption period, the refrigerant changes state from liquid to gas. This refrigerant gas can then be drawn into the compressor 106. The compressor is configured to increase the pressure of the refrigerant and transfer it to the condenser coil 108 (also referred to herein as the condenser). The condenser fan 110 is configured to circulate cold air through the condenser 108 to cool the refrigerant until it condenses (changes state from gas to liquid). The liquid refrigerant is then fed toward the evaporator 104.

[0030] Between the condenser 108 and the evaporator 104, the liquid refrigerant can pass through a receiver 112. The receiver 112 is configured to act as a refrigerant buffer, i.e., a storage tank for the refrigerant. By providing a device for accommodating excess refrigerant, this can provide greater flexibility in the amount of refrigerant supplied. The amount of refrigerant required depends on the predicted operating conditions of the cooling unit 100, for example, including suction pressure and condensing pressure. The amount of refrigerant required also depends on the value of subcooling. If the cooling unit 100 includes a smaller amount of refrigerant, a lower subcooling will result. The cooling unit 100 should include enough refrigerant so that it can provide the required cooling capacity, but it is not desirable to include too much refrigerant due to its high cost.

[0031] The refrigerant may also pass through a filter 114. The liquid refrigerant may also pass through a sight glass 116. The sight glass 116 includes a transparent window that allows the refrigerant to be visually inspected. The refrigerant may also pass through an expansion valve 118, such as an electronic expansion valve (EEV), which is configured to control the amount of refrigerant that flows back into the evaporator 104.

[0032] As described above, the refrigerant's properties change at different points along its journey through the refrigerant circuit. In the evaporator 104, the refrigerant absorbs heat and evaporates. In the compressor 106, the refrigerant's pressure increases, and due to the mechanical work of the compressor, the refrigerant's enthalpy also increases. In the condenser 108, as the refrigerant's enthalpy decreases, the refrigerant condenses. Finally, in the expansion valve 118, the refrigerant's pressure decreases. This cycle repeats as the refrigerant continues its journey through the refrigerant circuit.

[0033] The cooling unit 100 may include one or more pressure sensors ( Figure 1 Indicated as "P" in Figure 1 Temperature sensors (denoted as "T") in the refrigerant circuit. These sensors can be configured to determine and transmit the pressure / temperature of the refrigerant at various points in the refrigerant circuit.

[0034] If the refrigerant circuit is completely sealed, there is no need to refill the refrigerant. However, in practice, as described above, refrigerant may leak due to one or more defects or damage to the cooling unit 100 caused by mechanical fatigue, mechanical or chemical damage, or thermal fluctuations. The present disclosure provides an improved method for detecting leaks in a non-invasive, rapid, and non-destructive manner.

[0035] Figure 2 An example cooling system 200 according to the present disclosure is depicted. The cooling system 200 includes a plurality of cooling units 100-a, 100-b, ..., 100-n. In other words, the cooling system includes n cooling units, where n is an integer. Each of the cooling units 100-a, 100-b, ..., 100-n may correspond to Figure 1 , and reference numeral 100 is commonly used to refer to the cooling units 100 - a , 100 - b , . . . , 100 - n.

[0036] Each of the cooling units 100-a, 100-b, ..., 100-n may include a corresponding cooling unit controller 120-a, 120-b, ..., 120-n. Reference numeral 120 is collectively used to refer to the cooling unit controllers 120-a, 120-b, ..., 120-n. The cooling unit controllers 120 may be referred to herein as control devices or local controllers. Each of the cooling unit controllers 120-a, 120-b, ..., 120-n may be communicatively coupled to one, more than one, or all of the components of the corresponding cooling unit 100. Each cooling unit controller 120 may be configured to send control signals to the corresponding components of the corresponding cooling unit 100 to adjust the operation of the corresponding cooling unit. Alternatively or in addition, each cooling unit controller 120 may be configured to receive data from the corresponding components of the corresponding cooling unit 100. The data may include parameters of the cooling unit 100 describing the status of the components of the cooling unit 100 or physical parameters of the refrigerant or air in the cooling unit 100. Alternatively or additionally, for example, the data may include information that enables calculations to be performed or determinations of such parameters to be made by the respective cooling unit controller 120 .

[0037] The cooling system 200 may include a cooling system controller 220. The cooling system controller 220 may be referred to herein as a control device, a global controller, or a monitoring system. The cooling system controller 220 may be communicatively coupled to each of the cooling units 100. For example, the cooling system controller 220 may be communicatively coupled to each of the cooling unit controllers 120. For example, this may include the cooling system controller 220 sending the control signals and / or receiving the data described above. The cooling system controller 220 may perform calculations or determinations of the parameters described above.

[0038] Using a cooling system 200 that includes multiple cooling units 100 is advantageous because the cooling system 200 provides redundancy in the event that a particular one of the cooling units 100 fails or experiences reduced / stopped operation. This results in reduced downtime and a higher level of reliability for the cooling system 200 and the data center that the cooling system 200 is configured to cool.

[0039] Using a cooling system controller 220 communicatively coupled to each cooling unit 100 prevents the individual cooling units 100 from operating in conflicting ways (e.g., one unit humidifying the air while another unit dehumidifies the air), particularly when the cooling units 100 are located in the same room. This coordinated (or "teamed") operation of multiple cooling units 100 can save power and reduce potential control instability issues (e.g., activation / deactivation of individual cooling units 100). In this coordinated operation, the required total cooling load can be distributed among the cooling units 100, which can result in more stable and reliable operation from a quality control perspective.

[0040] Figure 3 An example method 300 for detecting leaks in a cooling system including multiple cooling units according to the present disclosure is depicted. The method 300 may be performed using any one or more of the cooling units 100, cooling system 200, cooling unit controller 120, and cooling system controller 220 described above.

[0041] In step 302 , the method may include adjusting operation of a first cooling unit 100 of a plurality of cooling units.

[0042] In step 304 , the method may include determining at least one parameter of the first cooling unit 100 while the first cooling unit 100 operates according to the adjusted operation.

[0043] In step 306 , the method may include, when the first cooling unit 100 operates according to the adjusted operation, operating at least one other cooling unit of the plurality of cooling units to compensate for the adjusted operation of the first cooling unit 100 .

[0044] In step 308 , the method may include comparing at least one parameter to a reference value.

[0045] The following sets forth additional details that may be included in or in conjunction with the method 300. It should be understood that references to the cooling unit 100 below may be used to refer to the first cooling unit 100 described above, or to refer to any other cooling unit 100 in the plurality of cooling units 100. The steps described below may be performed by the cooling unit controller 120 of the cooling unit 100 in question or by the cooling system controller 220.

[0046] With reference to comparing at least one parameter with a reference value as described above in step 308, the reference value may be determined by a baseline procedure (also referred to as a baseline creation process). The baseline procedure may be used to define normal or standard operating conditions for the cooling unit 100, i.e., operating conditions for a predefined operating mode in the absence of a leak. The baseline procedure may be performed once for each cooling unit 100, or periodically for each cooling unit 100, or may be performed immediately prior to major maintenance on the relevant cooling unit 100.

[0047] Typically, a cooling unit 100 in a data center may be operated at 50% to 80% of its nominal capacity. A check may be performed to determine whether the cooling unit 100 is operating within its design range. The gradual adjustment of the compressor may be fixed to a predetermined value, such as 50% (this value may vary based on the specific cooling unit 100 under consideration). The condensing temperature may be raised to a predetermined value, such as 50° C. (this value may vary based on the specific cooling unit 100 under consideration). The cooling unit 100 may be allowed to operate until it operates in a stable state. This may be determined based on the absence of oscillations greater than a defined threshold within a given time window.

[0048] As the cooling unit operates in a steady state, one or more parameters or variables of the cooling unit 100 may be determined. These parameters or variables may include one or more of suction pressure, suction temperature, superheat, condensing pressure, condensing temperature, subcooling, ambient temperature, compressor ramping, evaporator fan ramping, condenser fan ramping, EEV position, and / or a liquid level reading from a liquid level sensor. The reference value mentioned in step 308 above may include one or more of these parameters or variables. In other words, the reference value may be a measurement or determination based on a steady state or baseline or benchmark or standard (leak-free) operation of the cooling unit 100. The reference value may be stored in a storage device such as a computer memory.

[0049] With reference to steps 302 through 306 above, these steps can be performed according to an online procedure. This can be performed periodically, automatically, for example, according to an algorithm. The online procedure can include determining one or more current parameters of the cooling unit 100, which can then be compared to corresponding parameters from a baseline procedure. The online procedure can be performed at a time or times when cooling demand is low and / or stable. For example, the online procedure can be performed at night, when it is easier to manage to maintain the desired condensing temperature.

[0050] A check can be performed to determine whether the cooling units 100 are operational. A check can be performed to determine whether no cooling units 100 are experiencing errors or undergoing maintenance. A check can be performed to determine whether the total cooling capacity of a cooling site (e.g., a data center) is sufficient without problems. For example, a determination can be made whether the cooling capacity of a plurality of cooling units 100 exceeds the total cooling required by at least a threshold amount or a threshold percentage.

[0051] The leak detection techniques described herein can be performed in response to a determination that one or more of the above checks are met. Different safety levels can be considered for the above checks, and the safety level can depend on how critical it is to maintain continued operation. By way of example, consider a data center that includes ten cooling units that are actively providing cooling. For the highest safety level, the leak detection techniques can be performed in response to a determination that nine cooling units can meet the cooling demand of the ten cooling units that were previously in operation plus a safety threshold for the cooling demand. For the normal / medium safety level, the leak detection techniques can be performed in response to a determination that nine cooling units can meet the cooling demand of the ten cooling units that were previously in operation (regardless of any safety threshold or any cooling capacity of the tenth cooling unit). For the lowest safety level, the leak detection techniques can be performed in response to a determination that the maximum cooling capacity of the nine cooling units plus the cooling capacity provided by the tenth cooling unit when it is operating according to the adjusted operation can meet the cooling demand.

[0052] While the present disclosure is most particularly concerned with cooling units in a data center environment, it should be understood that this is described by way of illustrative example only, and that the features and techniques of the present disclosure are applicable to any suitable environment to be cooled and any suitable building to be cooled. For example, the cooling systems and cooling units of the present disclosure may be provided in commercial environments, retail environments, office environments, industrial environments, and the like. Any of these environments may have a cooling system comprising multiple cooling units and, therefore, may benefit from the improved leak detection and cooling reliability improvements provided by the features and techniques described herein.

[0053] During the testing of the first cooling unit 100, one of the cooling units 100 (hereinafter referred to as the "first cooling unit") can be excluded from the coordinated or team-like operation of the plurality of cooling units 100. The operation of the first cooling unit 100 can be adjusted or modified so that its operation corresponds to its operation during the baseline procedure described above. In other words, one or more control parameters of one of the cooling units 100 can be adjusted so that they correspond to the control parameters used during the baseline procedure and / or so that the operation of the cooling unit 100 corresponds to its operation during the baseline procedure (when the reference value was determined for that cooling unit 100).

[0054] The adjustment may include adjusting the evaporator fan 102 of one of the cooling units 100 (e.g., increasing or decreasing its speed) so that the operation of the evaporator fan 102 corresponds to its operation during the baseline procedure / so that the first cooling unit 100 is Figure 1 The operation of the low-pressure side at the bottom of the cooling unit 100 corresponds to its operation in this region during the baseline procedure. This may include the cooling unit 100 having the same suction pressure as during the baseline procedure. Alternatively, or in addition, the adjustment may include adjusting the operation of the condenser 108 of the first cooling unit 100 to adjust the condensing temperature to the value used during the baseline procedure. This may include a condensing pressure that corresponds to the condensing pressure used during the baseline procedure.

[0055] When the first cooling unit is operating according to the adjusted operation, the operation of one or more of the other cooling units 100 in the plurality of cooling units 100 can be adjusted, or can be operated in an adjusted manner, to compensate for it. For example, one or more of the other cooling units 100 can be gradually turned up to provide increased cooling and / or air delivery to compensate for the reduction in cooling and / or air delivery caused by the first cooling unit 100 being tested. Alternatively, if the test includes an increase in cooling and / or air delivery by the first cooling unit 100, one or more of the other cooling units 100 can be gradually turned down to provide reduced cooling and / or air delivery to compensate for it. In other words, the operation of the remaining cooling units 100 is adjusted to avoid an interruption in cooling delivery or a deviation in cooling delivery from the desired cooling.

[0056] After adjusting the operation of the first cooling unit 100, the first cooling unit 100 can be stabilized, i.e., operated until a steady state is reached. Subsequently, at least one parameter of the first cooling unit 100 can be determined. The at least one parameter can include one or more parameters or variables determined during the baseline procedure described above. At least one corresponding parameter can be determined during the baseline procedure and during the online procedure, allowing similar parameters to be compared with similar parameters. The one or more parameters can be stored in a storage device, such as a computer memory.

[0057] As explained above in step 308, at least one parameter may be compared to a reference value. The comparison may be performed while one of the cooling units 100 is operating according to the adjusted operation, or after it has returned to its standard operation according to the coordinated operation of the plurality of cooling units 100. Each of the one or more parameters determined during the online procedure may be compared to a corresponding reference value thereof (i.e., describing the same physical quantity and / or the same component of the first cooling unit 100).

[0058] The difference between the parameter and the reference value can be compared to a predetermined threshold. The threshold can be an absolute value or a percentage. The threshold can be different for different reference values / parameters, i.e., depending on which physical quantity and / or component of the first cooling unit 100 they describe. Each parameter can be compared to its corresponding reference value in sequence.

[0059] If the difference is above a predetermined threshold, a predetermined action may be taken. For example, a warning message may be generated and presented to an engineer. This may indicate that there is a leak in the first cooling unit 100. In response to the difference being above the predetermined threshold, in some examples, the first cooling unit 100 may not resume its operation according to the coordinated operation of the plurality of cooling units 100, and the remaining cooling units 100 may continue to provide the required cooling thereafter without the need for the first cooling unit 100. The first cooling unit 100 may be evacuated. In other examples, the first cooling unit 100 may resume its operation according to the coordinated operation, but if, for example, at least a predetermined number of warnings are generated for the cooling unit 100 within a predetermined time period, a warning is recorded to remove the first cooling unit 100 from the coordinated operation.

[0060] Alternatively, if the difference is below (or equal to) a predetermined threshold, the first cooling unit 100 may return to coordinated operation of the plurality of cooling units 100. The remaining cooling units 100 may readjust their operations to provide the required cooling capacity together with the first cooling unit 100.

[0061] The plurality of cooling units 100 may be allowed to stabilize, including gradually turning up or down individual cooling units 100 to provide the required cooling capacity between them. Subsequently, the online procedure described above may be repeated for one or more of the other cooling units 100 in the plurality of cooling units 100. While the second (and third, fourth, etc.) cooling unit 100 is being tested according to its own online procedure, the first cooling unit 100 may be in the remaining cooling units 100, for example, by providing additional cooling to compensate for the cooling unit 100 currently being tested.

[0062] The techniques of the present disclosure advantageously provide a non-invasive method for self-testing a particular cooling unit 100. For cooling units 100 comprising multiple circuits, these techniques can be performed sequentially on a specific one of these circuits. These techniques enable improved localization of any identified leaks, which can enable leaks to be identified and repaired more quickly and with reduced refrigerant loss.

[0063] The technology of the present disclosure enables any deviation of the cooling unit 100 from the baseline operation to be determined in a quantitative manner, which can be particularly sensitive to identifying the potential presence of a leak. The use of a threshold value to compare at least one parameter to a reference value allows the sensitivity of the described leak detection to be configured as desired. For example, in some settings, it may be desirable to set a low threshold value to achieve the fastest possible identification of a leak. In other settings, it may be desirable to set a higher threshold value to avoid potential false positives in leak detection and maintain the operation of the maximum number of cooling units 100 for as long as possible.

[0064] The techniques of the present disclosure provide the following advantageous combination: simultaneously determining the presence of a leak and continuing to provide the required cooling capacity, i.e., avoiding a negative impact on the cooling provided. In particular, because when one of the cooling units 100 is tested, the remaining cooling units 100 are configured to cover the total cooling capacity, the impact on the data center is negligible. There are no adverse consequences associated with adjusting the operation of a specific cooling unit 100 to check for leaks because the cooling provided is not interrupted. Therefore, leak detection does not have to be performed only when a leak is suspected, but can be performed regularly and automatically to detect any leaks earlier. This regular and preventative leak detection can provide a more reliable and robust cooling system 200.

[0065] The cooling system controller 220 can send commands to the respective cooling unit controllers 120 of each cooling unit 100 to initiate adjusted operation and / or to appropriately compensate for the adjusted operation of another cooling unit 100. These commands can be generated and / or sent according to a predefined schedule included in the memory of the cooling system controller 220. Alternatively, these commands can be generated and / or sent by a particular cooling unit controller 120 of a particular cooling unit 100 designated as the "master" cooling unit 100. Such commands can be initiated by an engineer, for example, if additional inspection of one or more of the cooling units 100 is desired.

[0066] The technology of the present disclosure is generally applicable to a variety of different determined parameters and reference values. The parameters and reference values ​​may include one, more, or all of the examples set forth below. The use of specific parameters and reference values ​​may be adapted to the specific components and sensors included in a specific type of cooling unit 100 or cooling system 200.

[0067] In a first example, leak detection may include determination of subcooling. Figure 4 An example cooling unit 400 is depicted that can be used to determine subcooling. The cooling unit 400 may include Figure 1 The cooling unit 100 described corresponds to features.

[0068] Subcooling refers to the temperature of the liquid refrigerant being lower than the boiling point of the refrigerant. The subcooling amount of the refrigerant can refer to how much lower its temperature is than the boiling point of the refrigerant. In particular, the temperature here can refer to the temperature of the refrigerant just after it passes through the condenser 108.

[0069] A reference value for the degree of subcooling of the refrigerant in the cooling unit 100 can be determined, which can be performed using the above-mentioned baseline procedure. A typical value for the degree of subcooling can be 2K (i.e., 2 degrees Kelvin) or greater. The degree of subcooling can be measured using a temperature sensor 402, which can be configured to determine the temperature of the refrigerant after it leaves the condenser 108 (and before it enters another component other than a pipe or conduit). The boiling point of the refrigerant can be known from a reference table or can be determined experimentally. The degree of subcooling of the refrigerant can be calculated by subtracting the temperature measured by the temperature sensor 402 from the known boiling point of the refrigerant.

[0070] According to the online procedure described above, the operation of the cooling unit 100 can be adjusted so that its operation corresponds to its operation during the baseline procedure described above. This can include modifying the evaporator 104 pressure so that it corresponds to the evaporator 104 pressure during the baseline procedure. The evaporator 104 pressure can be maintained at this constant value, for example, by modifying the evaporator fan 102 (see Figure 1 ) speed or the compressor 106 speed to achieve this. Figure 1 ) speed, the condensing pressure of the condenser 108 can be maintained at a constant value.

[0071] During the online procedure, the subcooling can be measured again using temperature sensor 402. In other words, the subcooling can be re-determined by subtracting the temperature measured by temperature sensor 402 from the known boiling point of the refrigerant. The subcooling determined in this manner is an example of at least one parameter of cooling unit 100 that is determined when cooling unit 100 operates according to the adjusted operation associated with the online procedure.

[0072] The subcooling (i.e., at least one parameter) determined during the online procedure can be compared to the subcooling (i.e., a reference value) determined during the baseline procedure. The comparison can include subtracting the parameter from the reference value (or alternatively, dividing the parameter by the reference value). If the subcooling determined during the online procedure is lower than the subcooling determined during the baseline procedure, this indicates that the amount of refrigerant in circulation has decreased, and therefore there may be a leak in the cooling unit 100.

[0073] In a second example, leak detection may include determination of an expansion valve position, such as determination of an electronic expansion valve (EEV) position. Figure 5An example cooling unit 500 is depicted that can be used to determine the location of an EEV. The cooling unit 500 may include Figure 1 The cooling unit 100 described corresponds to features.

[0074] Superheat refers to the temperature of the refrigerant in the gaseous state being higher than the boiling point of the refrigerant. The superheat of the refrigerant can refer to how much its temperature is lower than the boiling point of the refrigerant. In particular, the temperature here can refer to the temperature of the refrigerant just after it passes through the evaporator 104.

[0075] The EEV 118 can be configured to open or close to a degree that allows sufficient refrigerant to pass therethrough so that the refrigerant's superheat after passing through the evaporator 104 approaches a set point, i.e., a predetermined / desired superheat level. In other words, the EEV 118 provides a means for controlling the superheat level of the refrigerant. If the EEV 118 must be opened to a greater degree to maintain the flow of refrigerant that produces the desired superheat level, this indicates that the total amount of refrigerant in the cooling unit 100 is lower than the previous total amount of refrigerant.

[0076] A reference value for the position of the EEV 118 can be determined, which can be performed using the baseline procedure described above. For example, the EEV 118 can provide an electronic readout of the valve position to the corresponding cooling unit controller 120 or cooling system controller 220, or via an integrated display or a communicatively coupled display. Other types of valves can communicate the valve position in a corresponding manner, or the valve position can be determined in an alternative manner, such as via manual inspection or measurement.

[0077] During the online procedure, the EEV 118 position can again be determined as another example of at least one parameter of the cooling unit 100, the at least one parameter being determined while the cooling unit 100 is operating according to the adjusted operation associated with the online procedure. To this end, the operation of the cooling unit 100 can be adjusted so that its operation corresponds to its operation during the aforementioned baseline procedure.

[0078] The position of the EEV 118 determined during the online procedure can be compared to the position of the EEV 118 determined during the baseline procedure. If the comparison indicates that the position of the EEV 118 during the online procedure causes the valve to be more open than during the baseline procedure, this indicates that the amount of refrigerant in circulation has decreased, and therefore there may be a leak in the cooling unit 100.

[0079] Because of the correlation between the EEV 118 and the gradual adjustment of the compressor 106 during cooling delivery, as an alternative to or in addition to considering the increase in the opening degree of the EEV 118, an increase in the gradual adjustment of the compressor 106 can also be determined to indicate the presence of a leak as described herein. In other words, the current increase in the gradual adjustment of the compressor 106 can be used as a parameter to be compared with a reference value for the gradual adjustment of the compressor 106. This can serve as a double-check mechanism, which can result in a higher level of confidence in leak detection.

[0080] In a third example, leak detection may include determining the level of liquid refrigerant in the receiver. Figure 6 An example cooling unit 600 is depicted that can be used to determine the location of an EEV. The cooling unit 600 may include Figure 1 The cooling unit 100 described corresponds to features.

[0081] Figure 6 The receiver 602 depicted in FIG. Figure 1 Receiver 112 is present as depicted in FIG. Specifically, while receiver 112 is oriented horizontally, receiver 602 is oriented vertically. In other words, receiver 602 is sized such that it is longer in the vertical direction than in the horizontal direction. In other words, receiver 602 is longer in the direction of refrigerant flow than in a direction perpendicular to that direction.

[0082] The receiver 602 may include a liquid level sensor, or the liquid level sensor may be attached to, included in, or managed at the receiver 602. The liquid level sensor may be configured to determine the liquid level of the refrigerant in the receiver 602, i.e., the height of the top surface of the refrigerant in the receiver 602. As will be appreciated by those skilled in the art, the liquid level sensor may be implemented in a variety of different ways, including capacitive, magnetic, or ultrasonic sensors. Orienting the receiver 602 vertically makes the level sensor's measurements more sensitive to changes in the amount of refrigerant present, because in this orientation, a specific change in the volume of the refrigerant will result in a larger change in the height of the top surface of the refrigerant. It is advantageous to make the diameter of the receiver in the horizontal direction as small as possible to improve the accuracy of the level sensor's measurements.

[0083] In a manner corresponding to that described in the previous example, the baseline procedure described above can be used to determine a reference value for the refrigerant level 602. For example, a level sensor can provide an electronic readout of the refrigerant level position to the corresponding cooling unit controller 120 or cooling system controller 220, or via an integrated or communicatively coupled display. During the online procedure, the refrigerant level can again be determined as another example of at least one parameter of the cooling unit 100, the at least one parameter being determined while the cooling unit 100 is operating according to the adjusted operation associated with the online procedure. To this end, the operation of the cooling unit 100 can be adjusted so that its operation corresponds to its operation during the baseline procedure described above.

[0084] The refrigerant level determined during the online procedure can be compared to the refrigerant level determined during the baseline procedure. If the comparison indicates that the refrigerant level during the online procedure is lower than the refrigerant level during the baseline procedure, this indicates that the amount of refrigerant in circulation has decreased, and therefore there may be a leak in the cooling unit 100.

[0085] In a fourth example, leak detection may include determining that the sight glass 116 (see Figure 1 ) is present. If the subcooling of the refrigerant is small, it may be difficult to accurately determine the difference between the subcooling during the baseline procedure and the subcooling during the online procedure. Evaluation of the amount of bubbles on the sight glass 116 can provide an additional check to address this issue. Figure 7a and Figure 7b Each depicts a speculum 116 in the center of the image. Figure 7a In the embodiment, the sight glass 116 is transparent, and in the embodiment Figure 7b In the embodiment, the endoscope 116 is shadowed or becomes blurred due to the presence of bubbles on the inner surface of the endoscope 116.

[0086] The camera device may be directed to view the scope 116 and may be communicatively coupled to the corresponding cooling unit controller 120 or cooling system controller 220. One or more of the camera device, cooling unit controller 120, and / or cooling system controller 220 may include image analysis software configured to detect the presence of bubbles on the scope 116, for example, by determining the brightness of the image or detecting the outline of the bubble in the image.

[0087] An increased amount of bubbles 116 on the sight glass may indicate that some of the refrigerant is still in a gaseous state after passing through the condenser 108 and may indicate a low amount of subcooling. This in turn may indicate a low amount of refrigerant in the cooling unit 100. For example, Figure 7a The speculum 116 during the baseline procedure may be depicted, and Figure 7b The scope 116 may be depicted during an online procedure. Figure 7b Relative to Figure 7a An increase in the amount of bubbles may indicate that the amount of refrigerant in circulation has decreased, and thus there may be a leak in the cooling unit 100 .

[0088] In the fifth example, leak detection may include detecting bubbles on an attached sight glass.Thus, the fifth example may be considered a modified version of the fourth example. Figure 8 An example cooling unit 800 is depicted that can be used to detect bubbles according to a fifth example. The cooling unit 800 may include Figure 1 The cooling unit 100 described in the accompanying drawings corresponds to the features thereof.

[0089] The cooling unit 800 includes a bypass of the condenser 108. The cooling unit 800 may not include the receiver 112 (see Figure 1 ). The bypass includes a valve 802 (e.g., a solenoid valve) and a capillary tube through which the refrigerant can flow around the condenser 108, i.e., flow in parallel with the condenser 108. If the cooling unit 100 has a normal (high) degree of subcooling, the gas can flow through the bypass and mix with the liquid refrigerant on the other side of the condenser 108, causing the gas to condense. An additional sight glass 804 is provided in the cooling unit 100 after the gas and liquid meet, i.e., after the bypass, the condenser 108, and the valve 802. The sight glass 804 can be provided at a distance L from the point where the conduit to the condenser 108 and the bypass including the valve 802 meet, i.e., at a distance L after this point in the direction of refrigerant flow. The additional sight glass 804 can be used to determine whether the condensed refrigerant is cold enough to cause the gas to condense, so that no bubbles are visible on the additional sight glass 804. If this is not the case, bubbles will form on the inner surface of the additional sight glass 804. This may indicate that the amount of refrigerant in circulation has decreased, and therefore there may be a leak in the cooling unit 100. The assessment of the amount of bubbles can be performed using a camera and / or image analysis software in a manner corresponding to that described with respect to the fourth example. The amount of bubbles can be determined for the baseline procedure to determine a reference value, and the amount of bubbles can be determined for the online procedure to determine at least one parameter, and the reference value and the at least one parameter can be compared as described above.

[0090] In a sixth example, leak detection may include determining the temperature and / or pressure during or after the pump-down process. While the first through fifth examples described above may allow the cooling unit 100 to continue providing cooling (in an adjusted manner), during leak detection according to the sixth example, the cooling unit 100 will not be able to provide any cooling.

[0091] Figure 9 An example cooling unit 900 is depicted that can be used to determine temperature and / or pressure according to a sixth example. The cooling unit 900 may include Figure 1. Cooling unit 900 includes a liquid-side valve 902 and a gas-side valve 904. Liquid-side valve 902 can be disposed in the refrigerant circuit between sight glass 116 and expansion valve 118. Gas-side valve 904 can be disposed in the refrigerant circuit between compressor 106 and condenser 108. Each of liquid-side valve 902 and gas-side valve 904 can be an EEV valve, a solenoid valve, or any other suitable type of valve, and can be configured to control the flow of refrigerant therethrough.

[0092] According to a sixth example, the liquid side valve 902 can be closed and all possible refrigerant can be drawn from the evaporator side of the refrigerant circuit (i.e., the portion of the refrigerant circuit that includes and is close to the evaporator 104). The compressor 106 can be turned off and the evaporator fan 102 (see Figure 1 ) can be turned off, and the condenser fan 110 (see Figure 1 ) can be closed. After these steps, all of the refrigerant should be on the condenser side of the refrigerant circuit (ie, the portion of the refrigerant circuit that includes and is close to the condenser 108).

[0093] The outside temperature (e.g., the temperature measured on the condenser side / in the external environment outside the building comprising the data center) can be compared to a temperature calculated based on a pressure reading on the condenser side of the cooling unit 900. This pressure reading can be determined using a pressure sensor located on the condenser side of the cooling unit 900. If the temperature reading on the condenser side is considered directly, such readings may decrease over time, not due to a leak, but rather due to the refrigerant approaching the outside temperature. However, since there is no refrigerant flow, the refrigerant pressure will equalize with the refrigerant temperature. As will be appreciated by those skilled in the art, the conversion between pressure readings and equivalent temperatures can be performed using known curves relating temperature to pressure. These curves can take the form of polynomials stored in or accessible to the controllers 120, 220. In this way, a temperature calculated from the pressure reading can be determined and compared to the outside temperature. This comparison should be performed when the outside temperature is relatively constant, for example, at night. If the outside temperature is constant and the pressure on the condenser side (or the temperature calculated based on this pressure) is decreasing, this may indicate a leak in the cooling unit 100 on the condenser side.

[0094] The internal temperature (e.g., the temperature measured on the evaporator side of the interior of the building that constitutes the data center) can be compared to a temperature calculated based on a pressure reading on the evaporator side (i.e., the suction side) of the cooling unit 900. This pressure reading can be determined using a pressure sensor located on the gas side of the cooling unit 900, and the temperature can be calculated from this pressure reading in a manner corresponding to that described above for the condenser side of the cooling unit 900. Depending on the vacuum level that can be achieved on the evaporator side of the cooling unit 900, changes in this pressure reading can indicate the presence of a leak. For example, if the suction pressure can be reduced to 2 bar, and the suction pressure continues to decrease after closing valve 902, this can indicate the presence of a leak on the evaporator side. If the suction pressure can be reduced to below 1 bar, and the pressure increases after closing valve 902, this can indicate the presence of a leak on the suction side.

[0095] According to a sixth example, the reference value may include an external temperature measurement, and the at least one parameter may include a temperature calculated based on a pressure reading on the condenser side of the cooling unit 100. According to a sixth example, the reference value may include an internal temperature, and the at least one parameter may include a temperature calculated based on a pressure reading on the evaporator side of the cooling unit 100. According to a sixth example, the reference value may include a suction pressure to which the evaporator side may be reduced, and the at least one parameter may include the pressure on the evaporator side at a later time. According to a sixth example, the leak may be localized to the condenser side or the evaporator side of the cooling unit 900.

[0096] Any of the leak detection techniques described in this disclosure may be performed individually or in combination. Figures 4 to 9 Any of the components in the Figure 1 or Figure 2 The total number of leak detection technologies used and the specific leak detection technologies used can be selected based on the configuration of the cooling unit 100, the configuration of the cooling system 200, the equipment to be cooled, and / or user preferences. The greater the number of leak detection technologies used, the higher the confidence level in determining that a leak exists.

[0097] To ensure high confidence that a leak exists and reduce the risk of false positives, a summation logic can be used as described below. For n leak detection technologies (n is an integer), a weight w can be assigned to each technology based on its sensitivity and accuracy. By way of example, the sum of the weights w can add up to 1:

[0098]

[0099] The output or result of each of the n leak detection methods may be referred to as r and may be a binary indication, where r is equal to 1 if a leak is present and 0 if no leak is present. A confidence threshold may be defined (e.g., having a value between 0 and 1). The value calculated by multiplying each of the weights w by the corresponding output r is summed for all n leak detection methods, and if the value is above a certain confidence threshold, a predefined action may be performed on the cooling unit 100. This is summarized using the following equation:

[0100]

[0101] For ease of illustration, a non-limiting numerical example is provided below. Consider using five leak detection techniques (the number used in different examples may be lower or higher) and weighting them equally (the weighting may vary in different examples). Therefore, the weight w of each of the n techniques is equal to 0.2. We can then define different confidence thresholds of 0.2, 0.4, 0.6, etc.:

[0102]

[0103]

[0104] In the first case (value ≤ 0.2), only one of the techniques indicates that a leak exists. In this case, the predefined action may be to continue to monitor the cooling unit 100 regularly, but to take no further action.

[0105] In the second case (value ≤ 0.4), two of the techniques indicate that a leak exists. In this case, the predefined action may be to generate and / or transmit an alert indicating a possible leak.

[0106] In the third case (value ≤ 0.6), three of the techniques indicate the presence of a leak. The predefined action may be to generate and / or transmit an alert indicating a possible leak. The alert may be configured to be more prominent than the warning. For example, when displayed visually, the alert may be louder / brighter than the warning, and / or when transmitted audibly, the alert may be louder than the warning, and / or the alert may be distributed to more people / systems.

[0107] In the fourth case (value > 0.6), four or five of the techniques indicate the presence of a leak. The predefined action can be to initiate a safety routine for the cooling unit 100. For example, the cooling unit 100 can be shut down. In the fourth case, an alarm can also be generated and / or transmitted as in the third case. If one or more of the detection techniques indicate a specific location of a leak within the cooling unit 100, a specific action can be initiated in response. For example, if a leak is indicated on the evaporator side, the compressor 106 can be used to draw all the refrigerant to the condenser side, which can prevent further refrigerant loss.

[0108] It should be understood that other numbers of techniques, weights, confidence thresholds, and predefined actions may be used as appropriate.

[0109] The technology of the present disclosure enables quantitative and cooling unit-specific leak detection, thereby improving the accuracy of leak detection and reducing refrigerant loss due to leaks. In addition, the technology of the present disclosure enables such leak detection to be performed without interrupting the overall cooling provided by the cooling system, thereby improving the reliability of the cooling system. Furthermore, the technology of the present disclosure is modular and can be customized according to the type of cooling unit being operated and the required confidence level, thereby increasing the versatility of leak detection.

[0110] Although the methods disclosed herein are presented in a certain sequential order, this should not be construed as limiting the methods to the order presented. One or more of the method steps may be omitted or rearranged. The various steps may be performed in a different order. The various steps may be performed simultaneously or substantially simultaneously. Reference herein to substantially simultaneous events may refer to events that at least partially overlap in time and / or occur simultaneously within a measurement uncertainty.

[0111] The cooling unit, cooling system and / or controller described herein can be configured to perform any of the method steps currently disclosed, and can include computer-executable instructions that, when executed by a processor, cause the processor to perform any of the method steps currently disclosed, or that, when executed by a controller, cause the controller to perform any of the method steps currently disclosed, or that, when executed by the cooling unit / cooling system, cause the cooling unit / cooling system to perform any of the method steps currently disclosed. Any of the steps that the cooling unit, cooling system and / or controller are configured to perform can be considered as a method step of the present disclosure and can be implemented as computer-executable instructions for execution by a processor. The computer-readable medium can include the above-mentioned computer-executable instructions.

[0112] Figure 10A block diagram of an implementation of a computing device 1000 is shown, in which a set of instructions for causing the computing device to perform one or more of the methods discussed herein can be executed. In alternative implementations, the computing device can be connected (e.g., networked) to other machines in a local area network (LAN), an intranet, an extranet, or the Internet. The computing device can operate in the capacity of a server or client machine in a client-server network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The computing device can be a personal computer (PC), a tablet computer, a set-top box (STB), a personal digital assistant (PDA), a cellular phone, an internet access device, a server, a network router, a switch or a bridge, or any machine capable of executing a set of instructions (sequentially or non-sequentially) specifying actions to be taken by the machine. Furthermore, although only a single computing device is shown, the term "computing device" should also be considered to include any collection of machines (e.g., computers) that independently or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methods discussed herein. Computing device 1000 may correspond to one or more of cooling unit controllers 110 and / or cooling system controller 220 as described herein.

[0113] The example computing device 1000 includes a processing device 1002, a main memory 1004 (e.g., read-only memory (ROM), flash memory, dynamic random access memory (DRAM) such as synchronous DRAM (SDRAM) or memory bus DRAM (RDRAM)), a static memory 1006 (e.g., flash memory, static random access memory (SRAM), etc.), and a secondary memory (e.g., a data storage device 1018), which communicate with each other via a bus 1030.

[0114] Processing device 1002 represents one or more general-purpose processors, such as microprocessors, central processing units, and the like. More specifically, processing device 1002 may be a complex instruction set computing (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction word (VLIW) microprocessor, a processor implementing other instruction sets, or a processor implementing a combination of instruction sets. Processing device 1002 may also be one or more special-purpose processing devices, such as an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a digital signal processor (DSP), a network processor, and the like. Processing device 1002 is configured to execute processing logic (instructions 1022) to perform the operations and steps discussed herein.

[0115] The computing device 1000 may also include a network interface device 1008. The computing device 1000 may also include a video display unit 1010 (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)), an alphanumeric input device 1012 (e.g., a keyboard or a touch screen), a cursor control device 1014 (e.g., a mouse or a touch screen), and an audio device 1016 (e.g., a speaker).

[0116] The data storage device 1018 may include one or more machine-readable storage media (or more specifically, one or more non-transitory computer-readable storage media) 1028 on which one or more sets of instructions 1022 for implementing one or more of the methods or functions described herein are stored. The instructions 1022 may also reside, completely or at least partially, within the main memory 1004 and / or within the processing device 1002 during execution thereof by the computing system 1000, the main memory 1004 and the processing device 1002 also constituting computer-readable storage media.

[0117] The various methods described above can be implemented by a computer program. The computer program may include a computer code that is arranged to instruct a computer to perform the function of one or more of the various methods described above. The computer program and / or code for performing such a method may be provided to a device such as a computer on one or more computer-readable media or more generally a computer program product. The computer-readable medium may be transient or non-transient. For example, one or more computer-readable media may be electronic, magnetic, optical, electromagnetic, infrared or semiconductor systems or propagation media for data transmission, for example, propagation media for downloading code via the Internet. Alternatively, one or more computer-readable media may be in the form of one or more physical computer-readable media, for example, semiconductor or solid-state memory, magnetic tape, removable computer disk, random access memory (RAM), read-only memory (ROM), hard disk and optical disk such as CD-ROM, CD-R / W or DVD.

[0118] In implementation, the modules, components, and other features described herein may be implemented as discrete components, or integrated into the functionality of hardware components such as ASICs, FPGAs, DSPs, or similar devices.

[0119] A "hardware component" is a tangible (e.g., non-transitory) physical component (e.g., a collection of one or more processors) that is capable of performing certain operations and may be configured or arranged in some physical manner. A hardware component may include dedicated circuitry or logic that is permanently configured to perform certain operations. A hardware component may be or include a dedicated processor, such as a field programmable gate array (FPGA) or an ASIC. A hardware component may also include programmable logic or circuitry that is temporarily configured to perform certain operations through software.

[0120] Thus, the phrase "hardware component" should be understood to include a tangible entity that can be physically constructed, permanently configured (e.g., hardwired), or temporarily configured (e.g., programmed) to operate in a certain manner or perform certain operations described herein.

[0121] In addition, modules and components can be implemented as firmware or functional circuit systems within hardware devices. In addition, modules and components can be implemented in any combination of hardware devices and software components, or only in software (e.g., code stored or otherwise implemented in a machine-readable medium or transmission medium).

[0122] Unless otherwise expressly stated, as will be apparent from the following discussion, it will be understood that throughout this description, discussions utilizing terms such as "receiving," "determining," "comparing," "enabling," "maintaining," "identifying," "adjusting," "transmitting," "generating," "operating," and the like refer to the actions and processes of a computer system or similar electronic computing device that manipulates data represented as physical (electronic) quantities within the computer system's registers and memories to transform that data into other data similarly represented as physical quantities within the computer system's memories or registers or other such information storage, transmission, or display devices.

[0123] The methods described herein may be implemented on a computer-readable medium, which may be a non-transitory computer-readable medium. The computer-readable medium may carry computer-readable instructions that are arranged to be executed on a processor so as to cause the processor to perform any or all of the methods described herein.

[0124] As used herein, the term "computer-readable medium" refers to any medium that stores data and / or instructions to cause a processor to operate in a specific manner. Such storage media may include non-volatile media and / or volatile media. Non-volatile media may include, for example, optical or magnetic disks. Volatile media may include dynamic memory. Exemplary forms of storage media include floppy disks, flexible disks, hard disks, solid-state drives, magnetic tape or any other magnetic data storage medium, CD-ROMs, any other optical data storage medium, any physical medium having one or more hole patterns, RAM, PROM, EPROM, FLASH-EPROM, NVRAM, and any other memory chip or memory cassette.

[0125] It should be understood that the above description is intended to be illustrative, not restrictive. After reading and understanding the above description, many other implementations will be apparent to those skilled in the art. Although the present disclosure has been described with reference to specific example implementations, it should be appreciated that the present disclosure is not limited to the described embodiments, but can be practiced by modification and alteration within the scope of the appended claims. Therefore, the description and drawings are to be considered in an illustrative, rather than a restrictive, sense. Therefore, the scope of the present disclosure should be determined with reference to the appended claims and the full scope of equivalents to which these claims are entitled.

Claims

1. A method for detecting a leak in a cooling system comprising a plurality of cooling units, the method comprising: adjusting operation of a first cooling unit among the plurality of cooling units; When the first cooling unit operates according to the adjusted operation: determining at least one parameter of the first cooling unit; and operating at least one other cooling unit of the plurality of cooling units to compensate for the adjusted operation of the first cooling unit; as well as The at least one parameter is compared to a reference value.

2. The method according to claim 1, comprising: A difference between the at least one parameter and the reference value is compared with a threshold value.

3. The method according to claim 2, comprising: If the difference is greater than the threshold, a warning is generated, an alarm is generated, or the first cooling unit is powered off.

4. The method according to claim 2, comprising: If the difference is less than the threshold, the first cooling unit is restored to normal operation, and the at least one other cooling unit is restored to normal operation.

5. A method according to any preceding claim, wherein: The reference value is determined during a baseline procedure and the at least one parameter is determined during an online procedure, the method comprising operating the first cooling unit during the online procedure in a manner corresponding to that during the baseline procedure.

6. The method according to claim 5, wherein: The at least one parameter includes a subcooling degree of the first cooling unit during the online procedure, and the reference value includes a subcooling degree of the first cooling unit during the baseline procedure.

7. The method according to claim 5 or claim 6, wherein: The at least one parameter comprises a position of an expansion valve of the first cooling unit during the online procedure, and the reference value comprises a position of the expansion valve during the baseline procedure.

8. The method according to any one of claims 5 to 7, wherein The at least one parameter comprises a level of refrigerant in a vertical receiver of the first cooling unit during the online procedure, and the reference value comprises a level of refrigerant in the vertical receiver during the baseline procedure.

9. The method according to any one of claims 5 to 8, wherein The at least one parameter comprises an amount of bubbles on a sight glass of an expansion valve of the first cooling unit during the online procedure, and the reference value comprises an amount of bubbles on the sight glass during the baseline procedure; and / or wherein the at least one parameter comprises an amount of bubbles on a second sight glass of the first cooling unit during the online procedure, and the reference value comprises an amount of bubbles on the second sight glass during the baseline procedure, the second sight glass being configured to receive liquid refrigerant from a condenser of the first cooling unit and gas from a bypass of the condenser.

10. A method according to any preceding claim, comprising: Refrigerant is removed from the first cooling unit and one or more components of the first cooling unit are shut down, wherein the at least one parameter comprises a temperature calculated based on an internal pressure measurement of the first cooling unit, and the reference value comprises an external temperature measured outside the first cooling unit.

11. A method according to any preceding claim, comprising: determining a plurality of parameters of the first cooling unit; as well as Each of the plurality of parameters is compared to a corresponding reference value.

12. The method according to claim 11, comprising: For each of the plurality of parameters, quantifying the comparison result and weighting the quantified comparison result; adding the weighted and quantized comparison results to determine a leak detection value; as well as The leak detection value is compared to at least one confidence threshold, each confidence threshold being associated with a corresponding predetermined action.

13. A method according to any preceding claim, comprising: adjusting operation of a second cooling unit among the plurality of cooling units; When the second cooling unit operates according to the adjusted operation: determining at least one parameter of the second cooling unit; and operating at least one other cooling unit of the plurality of cooling units to compensate for the adjusted operation of the second cooling unit; as well as The at least one parameter is compared to a reference value.

14. A control device comprising a processor and a memory storing computer executable instructions which, when executed, cause the processor to perform a method according to any preceding claim.

15. A cooling system comprising: The control device according to claim 14; as well as Multiple cooling units.

Images