CN117232090A

CN117232090A - Refrigerant leakage detection method, water chiller, and computer-readable storage medium

Info

Publication number: CN117232090A
Application number: CN202210637057.7A
Authority: CN
Inventors: 祝用华; 袁永莉; 范波
Original assignee: GD Midea Heating and Ventilating Equipment Co Ltd; Shanghai Meikong Smartt Building Co Ltd
Current assignee: GD Midea Heating and Ventilating Equipment Co Ltd; Shanghai Meikong Smartt Building Co Ltd
Priority date: 2022-06-07
Filing date: 2022-06-07
Publication date: 2023-12-15

Abstract

The invention discloses a refrigerant leakage detection method, a water chiller and a computer readable storage medium, aiming at improving the accuracy of water chiller leakage detection. The high-pressure side pressure of the compressor, the low-pressure side pressure of the compressor, the actual rotating speed of the compressor and the actual guide vane opening of the compressor can be obtained; obtaining a first flow value of the refrigerant flowing through the compressor according to the restriction relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening; acquiring a second flow value of the refrigerant flowing through the throttling device; because the flow rate of the refrigerant flowing through the compressor and the flow rate of the refrigerant flowing through the throttling device are equivalent when the system is balanced, whether the refrigerant leaks or not can be determined through the first flow rate value and the second flow rate value, and then accurate detection of the refrigerant leakage is realized.

Description

Refrigerant leakage detection method, water chiller, and computer-readable storage medium

Technical Field

The invention relates to the technical field of water coolers, in particular to a refrigerant leakage detection method, a water cooler and a computer readable storage medium.

Background

The water chiller has large capacity and high efficiency and is widely applied to air conditioning systems of large and medium-sized buildings. The condition that the performance of the unit is reduced and faults occur inevitably when the water chiller runs for a long time, for example, the condition that the refrigerant leaks easily occurs in a system after the water chiller runs for a long time because the welding points and the connectors of the water chiller are relatively more, so that the timely detection of the refrigerant leakage becomes a problem to be solved urgently.

In general, the refrigerant leakage condition can be judged according to the temperature change rule of the heat exchanger, for example, when the temperature difference between the inner side and the outer side of the heat exchanger is greater than a certain threshold value, the current refrigerant leakage can be determined.

However, the above refrigerant leakage detection method is low in accuracy.

Disclosure of Invention

The main object of the present application is to provide a refrigerant leakage detection method, a water chiller and a computer readable storage medium, aiming at improving the accuracy of refrigerant leakage detection.

In the technical scheme of the application, the high-pressure side pressure of the compressor, the low-pressure side pressure of the compressor, the actual rotating speed of the compressor and the actual guide vane opening of the compressor can be obtained; obtaining a first flow value of the refrigerant flowing through the compressor according to the restriction relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening; acquiring a second flow value of the refrigerant flowing through a throttling device, wherein the throttling device is arranged between the condenser and the evaporator; and determining whether the refrigerant leaks according to the first flow value and the second flow value.

In the application, when the system is balanced, the flow rate of the refrigerant flowing through the compressor is equivalent to the flow rate of the refrigerant flowing through the throttling device, so that whether the refrigerant leaks or not can be determined through the first flow rate value and the second flow rate value, and further, the accurate detection of the refrigerant leakage is realized.

Based on the technical scheme, the application can also be improved as follows:

further, determining whether the refrigerant is leaking based on the first flow value and the second flow value includes: determining that the refrigerant leaks when the difference between the first flow value and the second flow value is greater than or equal to a first threshold value; alternatively, it is determined that the refrigerant is not leaked when the difference between the first flow value and the second flow value is less than the first threshold value.

Further, determining the refrigerant leak when the difference between the first flow value and the second flow value is greater than or equal to a first threshold value comprises: the refrigerant leak is determined when the time when the difference between the first flow value and the second flow value is greater than or equal to the first threshold exceeds the second threshold.

Further, according to the constraint relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotation speed and the actual guide vane opening, a first flow value of the refrigerant flowing through the compressor is obtained, and the method comprises the following steps: obtaining a target rotating speed and a target guide vane opening according to a third flow value preset by the compressor and the ratio of the high-pressure side pressure to the low-pressure side pressure; wherein, the third flow rate value, the ratio and the target rotating speed have a corresponding relation; the third flow rate value, the ratio and the opening degree of the target guide vane have a corresponding relation; and when the difference value between the target rotating speed and the actual rotating speed is smaller than or equal to a third threshold value and the difference value between the opening of the target guide vane and the opening of the actual guide vane is smaller than or equal to a fourth threshold value, determining the third flow value as the first flow value.

Further, when the difference between the target rotation speed and the actual rotation speed is greater than a third threshold value, and/or the difference between the opening of the target guide vane and the opening of the actual guide vane is greater than a fourth threshold value, the third flow rate value is adjusted, and the adjusted third flow rate value is obtained; obtaining a target rotating speed and a target guide vane opening according to a third flow value preset by the compressor and the ratio of the high-pressure side pressure to the low-pressure side pressure, wherein the method comprises the following steps of: and obtaining the target rotating speed and the target guide vane opening according to the adjusted third flow value and the ratio of the high-pressure side pressure to the low-pressure side pressure.

Further, the third flow value is a volumetric flow, and determining the third flow value as the first flow value includes: obtaining mass flow corresponding to the third flow value according to the third flow value and the first density of the refrigerant flowing through the compressor; wherein the first density is based on the low side pressure and a suction temperature of the compressor; the mass flow is determined to be a first flow value.

Further, obtaining a second flow rate value of the refrigerant flowing through the throttling device includes: obtaining a second flow value according to the high-pressure side pressure, the low-pressure side pressure, the second density of the refrigerant flowing through the throttling device, the flow area of the throttling device and the flow coefficient of the throttling device; wherein the second density is based on the high side pressure and the inlet temperature of the throttling device.

Further, the number of compressors is plural, the number of throttles is plural, and determining whether the refrigerant leaks according to the first flow value and the second flow value includes: determining whether the refrigerant leaks based on the sum of the plurality of first flow values and the sum of the plurality of second flow values.

Further, determining whether the refrigerant is leaking based on the sum of the plurality of first flow values and the sum of the plurality of second flow values, comprising: determining that the refrigerant leaks when the difference between the sum of the plurality of first flow values and the sum of the plurality of second flow values is greater than or equal to a fifth threshold; alternatively, it is determined that the refrigerant is not leaked when a difference between the sum of the plurality of first flow rate values and the sum of the plurality of second flow rate values is less than a fifth threshold value.

Further, the method further comprises: executing a preset maintenance flow when determining that the refrigerant leaks; the maintenance flow comprises the following steps: a down-conversion process, or an automatic shutdown process.

Further, the method further comprises: and when the refrigerant leakage is determined, sending indication information for indicating the refrigerant leakage to the electronic equipment, and carrying out refrigerant leakage prompt according to the indication information by the electronic equipment.

Further, when the number of the throttle devices is plural, the plural throttle devices are disposed in parallel between the condenser and the evaporator.

The invention also provides a water chiller, which is used for executing the method according to any one of the technical schemes.

The invention also provides electronic equipment, which comprises a processor, wherein the processor is used for executing any one of the methods in the technical scheme.

The invention also provides a computer readable storage medium storing a computer program which, when executed by a processor, implements a method according to any one of the above technical solutions.

The invention also provides a refrigerant leakage detection system, which comprises a cold water machine and electronic equipment, wherein after a processor of the cold water machine obtains the high-pressure side pressure of a compressor, the low-pressure side pressure of the compressor, the actual rotating speed of the compressor and the actual guide vane opening of the compressor, the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening are sent to the electronic equipment; the electronic equipment acquires a high-pressure side pressure, a low-pressure side pressure, an actual rotating speed and an actual guide vane opening from the water chiller, and obtains a first flow value of the refrigerant flowing through the compressor according to a constraint relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening; the electronic equipment obtains a second flow value of the refrigerant flowing through the throttling device; the electronics determine whether the refrigerant is leaking based on the first flow value and the second flow value.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to the structures shown in these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a scene provided in an embodiment of the present application;

fig. 2 is a schematic flow chart of a refrigerant leakage detection method according to an embodiment of the present application;

FIG. 3 is a flow chart of obtaining a first flow value according to an embodiment of the present application;

FIG. 4 is a schematic flow chart of another refrigerant leakage detection method according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a water chiller 500 according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a refrigerant leakage detecting device 600 according to an embodiment of the present application;

fig. 7 is a schematic diagram of a refrigerant leak detection system 700 according to an embodiment of the application.

Detailed Description

In the running process of the water chiller, the refrigerant leakage can bring a series of problems such as increased energy consumption of the compressor, reduced service life of a system of the water chiller and the like, so that the timely detection of the refrigerant leakage state becomes an urgent problem to be solved.

In the related art, the leakage condition of the refrigerant can be judged through the temperature change rule of the heat exchanger, for example, when the temperature difference between the inner side and the outer side of the heat exchanger is greater than or equal to a certain threshold value, the current leakage of the refrigerant can be determined; or when the temperature difference between the inner side and the outer side of the heat exchanger is smaller than a certain threshold value, the current refrigerant can be determined not to leak.

However, the heat exchanger temperature variation may be affected by various reasons such as cleaning conditions of the heat exchanger, fluid flow rate, or refrigerant leakage. Therefore, the refrigerant leakage detection by utilizing the change of the temperature difference between the inner side and the outer side of the heat exchanger has lower accuracy and is easy to generate misjudgment.

In view of this, the embodiment of the invention obtains the high-pressure side pressure of the compressor, the low-pressure side pressure of the compressor, the actual rotation speed of the compressor and the actual guide vane opening of the compressor; obtaining a first flow value of the refrigerant flowing through the compressor according to the restriction relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening; a second flow rate value of the refrigerant flowing through the throttling device is obtained. Since the first flow value can be understood as the flow of the refrigerant required by the system under the condition that the refrigeration requirement is unchanged, the second flow value can be understood as the corresponding flow of the refrigerant when the system is actually operated in a circulating way, and when the system is balanced, the flow of the refrigerant flowing through the compressor is equivalent to the flow of the refrigerant flowing through the throttling device, so that whether the refrigerant leaks or not can be determined through the first flow value and the second flow value, and further, the accurate detection of the refrigerant leakage is realized.

The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

Fig. 1 is a schematic view of a scenario provided in an embodiment of the present application. As shown in fig. 1, the scenario may include: a chiller (or chiller unit) 101, an electronic device 102, a server 103, and the like. The electronic device 102 is exemplified as a mobile phone, and this example is not meant to limit embodiments of the present application. The water chiller may be a centrifugal chiller.

In one implementation, the refrigerant leak detection method described in the embodiments of the present application may be implemented in the water chiller 101. The water chiller 101 may include at least a compressor, a throttle device, and a processor that may be used to perform the refrigerant leak detection method described in the embodiments of the present application.

In another implementation, the refrigerant leak detection method described in embodiments of the present application may be implemented in the electronic device 102. For example, in the case where the water chiller 101 establishes a connection with the electronic device 102, the water chiller 101 may transmit the acquired data of the high-side pressure of the compressor, the low-side pressure of the compressor, the actual rotational speed of the compressor, the actual vane opening of the compressor, and the like to the electronic device 102, so that the electronic device 102 may perform refrigerant leak detection based on the data acquired from the water chiller 101.

In still another implementation, the refrigerant leak detection method described in the embodiments of the present application may be implemented in the server 103. For example, in the case where the water chiller 101 establishes a connection with the server 103, the water chiller 101 may transmit the acquired data of the high-side pressure of the compressor, the low-side pressure of the compressor, the actual rotation speed of the compressor, the actual vane opening of the compressor, and the like to the server 103, so that the server 103 may perform refrigerant leak detection based on the data acquired from the water chiller 101. Further, the server 103 may also send the detection result to the electronic device 102, so that a serviceman may maintain the water chiller 101 based on the detection result displayed in the electronic device 102.

It is to be understood that the execution subject of the refrigerant leak detection method in the embodiment of the application is not particularly limited.

Fig. 2 is a schematic flow chart of a refrigerant leakage detection method according to an embodiment of the present application. In the embodiment corresponding to fig. 2, the main body of execution of the refrigerant leakage detection method is exemplified as a water chiller, and this example is not intended to limit the embodiment of the present application. As shown in fig. 2, the refrigerant leakage detecting method may include the steps of:

S201, acquiring the high-pressure side pressure of the compressor, the low-pressure side pressure of the compressor, the actual rotating speed of the compressor and the actual guide vane opening of the compressor.

Wherein the high side pressure may comprise: condensing pressure of the compressor, discharge pressure of the compressor, etc.; the low side pressure may include: the evaporation pressure of the compressor, or the suction pressure of the compressor, etc.; the condensing pressure, the discharge pressure, the evaporating pressure, and the suction pressure may all be detected based on a pressure sensor; the rotational speed may be calculated based on the current and torque of the motor; the opening of the guide vane may be detected based on a sensor connected to the guide vane. The condensing pressure can also be obtained by calculating the condensing outlet temperature of the compressor and the condensing supercooling degree of the compressor; the condensation outlet temperature may be based on detection of the outlet temperature of the condenser by a temperature sensor.

It is understood that the execution subject corresponding to the step shown in S201 may be: the processor in the water chiller, the electronic device connected to the water chiller, or the server connected to the water chiller, etc., which is not limited in the embodiment of the present application. When the execution body corresponding to the step shown in S201 is an electronic device (or a server), the method further includes, before S201: after the processor in the chiller acquires the high side pressure of the compressor, the low side pressure of the compressor, the actual rotational speed of the compressor, and the actual vane opening of the compressor, the high side pressure, the low side pressure, the actual rotational speed, and the actual vane opening are sent to the electronic device (or server).

S202, obtaining a first flow value of the refrigerant flowing through the compressor according to the constraint relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening.

Illustratively, a pressure ratio is calculated from the high side pressure and the low pressure, and the pressure ratio may be used to obtain a target speed of the compressor and a target vane opening; further, a first flow value is obtained based on a constraint relationship between the target rotational speed and the actual rotational speed, and a constraint relationship between the target vane opening and the actual vane opening.

S203, acquiring a second flow value of the refrigerant flowing through the throttling device.

Wherein the throttle device may be referred to as: the specific form of the throttle device is not limited in the embodiment of the application, such as a throttle valve, an expansion valve (e.g. an electronic expansion valve), or a combination of the expansion valve and a throttle plate; the second flow value may be related to the high side pressure, the low side pressure, a second density of the refrigerant flowing through the restriction, a flow area of the restriction, and a flow coefficient of the restriction.

It can be understood that, because the second flow value can be understood as the corresponding refrigerant flow when the water chiller actually circulates and operates, and the second flow value will be greatly affected when the throttling device fails, in order to ensure the accuracy of the second flow value, the second flow value of the refrigerant flowing through the throttling device can be obtained under the condition that the throttling device is determined not to fail.

Wherein the throttling device is arranged between the condenser and the evaporator. Further, when the number of the throttle devices is plural, the plural throttle devices are disposed in parallel between the condenser and the evaporator.

S204, determining whether the refrigerant leaks according to the first flow value and the second flow value.

It will be appreciated that since the first flow rate value of the refrigerant flowing through the compressor is equal to the second flow rate value of the refrigerant flowing through the throttling device when the water chiller is operating normally, it is possible to determine that the refrigerant is not leaked when the first flow rate value is equal to the second flow rate value, and to determine that the refrigerant is leaked when the first flow rate value is greatly different from the second flow rate value.

It can be understood that the execution subject corresponding to the steps shown in S202 to S204 may be: the processor in the water chiller, the electronic device connected to the water chiller, or the server connected to the water chiller, etc., which is not limited in the embodiment of the present application.

Based on this, can be through the flow number value that the refrigerant flowed through the compressor and the flow number value that the refrigerant flowed through throttling arrangement, accurate judgement refrigerant whether leak to adopt the numerical value of conventional measurement to carry out refrigerant leak detection, can increase the convenience of implementation.

On the basis of the corresponding embodiment of fig. 2, S204 includes: determining that the refrigerant leaks when the difference between the first flow value and the second flow value is greater than or equal to a first threshold value; alternatively, it is determined that the refrigerant is not leaked when the difference between the first flow value and the second flow value is less than the first threshold value.

The value of the first threshold may be a specific value, or may also be a value range, which is not limited in the embodiment of the present application; the difference between the first flow value and the second flow value may be: the difference of the first flow value minus the second flow value (or the absolute value of the difference), or the second flow value minus the first flow value (or the absolute value of the difference).

It will be appreciated that different water chiller capacities may correspond to different unit capacities, and that the difference in capacities will also affect the value of the first threshold. Therefore, the value under the leakage scene of the water chiller under the normal condition can be determined by the difference value between the first flow value and the second flow value, the difference value percentage obtained by dividing the total capacity of the unit, and the threshold value percentage obtained by dividing the first threshold value by the total capacity of the unit.

For example, when the first threshold is a specific value, the threshold percentage corresponding to the first threshold may be a value such as 1%, or 5%; or when the first threshold is a numerical value range, the range of the threshold percentage corresponding to the range where the first threshold is located may be 1% -10%, which is not particularly limited in the embodiment of the present application.

Further, a plurality of value ranges corresponding to the first threshold (or the threshold percentage corresponding to the first threshold) may be set, and the plurality of value ranges may correspond to different refrigerant leakage levels. It can be appreciated that, since the first flow value may be a refrigerant flow required by the water chiller under the condition that the refrigeration requirement is unchanged, the second flow value is a corresponding refrigerant flow when the water chiller is actually operated in a circulating manner, and the difference between the first flow value and the second flow value may represent the severity of the refrigerant leakage, different refrigerant leakage levels may be set, so that the water chiller may execute corresponding maintenance procedures under the different refrigerant leakage levels.

For example, a value range of 3 threshold percentages corresponding to the first threshold may be set, including: the range of values for the light refrigerant leakage level, such as the threshold percentage range of 1% -3% (e.g., may include: 1%, 2% and 3%); the range of the medium refrigerant leakage level corresponds to the range of 3% -6% (for example, 4%, 5% and 6%); and the range of values corresponding to the severe refrigerant leakage level, such as the range of values of 6% -10% (e.g. may include: 7%, 9%, and 10%) of the threshold percentage.

For example, when the difference percentage is detected to be 1% -3%, the water chiller determines that the current level is a slight refrigerant leakage level, and the water chiller can keep normal operation and send prompt information to the electronic equipment; when the difference percentage is detected to be 3% -6%, the water chiller determines that the current medium refrigerant leakage level is achieved, the water chiller can execute a frequency reduction process, and prompt information is sent to the electronic equipment; or when the difference percentage is detected to be 6% -10%, the water chiller determines that the current heavy refrigerant leakage level is met, the water chiller can execute an automatic shutdown process, an alarm is initiated, and prompt information is sent to the electronic equipment.

It will be appreciated that the number of refrigerant leak levels, the range of values for the threshold percentage for the refrigerant leak levels, and the maintenance procedures performed by the chiller at different refrigerant leak levels are merely examples, and are not limited in this embodiment of the application.

Based on the above, whether the refrigerant leaks or not can be accurately judged by the difference value between the flow value of the refrigerant flowing through the compressor and the flow value of the refrigerant flowing through the throttling device; and the maintenance flow under different refrigerant leakage levels is realized, and the normal operation of the water chiller is ensured.

On the basis of the embodiment corresponding to fig. 2, the refrigerant leakage is determined when the time when the difference between the first flow rate value and the second flow rate value is greater than or equal to the first threshold value exceeds the second threshold value.

The value of the second threshold may be a specific value, or may also be a value range of time, which is not limited in the embodiment of the present application.

In an exemplary case where the value of the second threshold is 1 minute, the refrigerant leakage is determined when the time when the difference between the first flow rate value and the second flow rate value is greater than or equal to the first threshold exceeds one minute. Alternatively, the chiller may count an average of differences between the first flow rate value and the second flow rate value over a period of time, and may determine that the refrigerant has leaked when it is determined that the average of differences is greater than a threshold over the period of time.

It will be appreciated that the specific implementation of determining the refrigerant leak using the difference between the first flow value and the second flow value in embodiments of the present application is not limited.

Further, a plurality of value ranges corresponding to times when the difference is greater than or equal to the first threshold may also be set, and the plurality of value ranges may correspond to different refrigerant leakage levels. Wherein, the related description of the refrigerant leakage level is not repeated herein.

Based on this, whether the refrigerant leaks or not can be accurately discriminated by the time when the difference between the flow rate value of the refrigerant flowing through the compressor and the flow rate value of the refrigerant flowing through the throttling device exceeds the first threshold value, and the robustness of the refrigerant leak detection can be increased.

On the basis of the corresponding embodiment of fig. 2, S202 includes: obtaining a target rotating speed and a target guide vane opening according to a third flow value preset by the compressor and the ratio of the high-pressure side pressure to the low-pressure side pressure; and when the difference value between the target rotating speed and the actual rotating speed is smaller than or equal to a third threshold value and the difference value between the opening of the target guide vane and the opening of the actual guide vane is smaller than or equal to a fourth threshold value, determining the third flow value as the first flow value.

Or when the difference value between the target rotating speed and the actual rotating speed is larger than a third threshold value and/or the difference value between the opening of the target guide vane and the opening of the actual guide vane is larger than a fourth threshold value, adjusting the third flow rate value to obtain an adjusted third flow rate value; and obtaining the target rotating speed and the target guide vane opening according to the adjusted third flow value and the ratio of the high-pressure side pressure to the low-pressure side pressure.

Wherein, the third flow rate value, the ratio and the target rotating speed have a corresponding relation; the third flow rate value, the ratio and the target guide vane opening have a corresponding relation.

For example, one possible implementation of determining the first flow value according to the preset third flow value, the high side pressure, the low side pressure, the actual rotational speed, and the actual vane opening of the compressor may be referred to as an embodiment corresponding to fig. 3 described below. Fig. 3 is a schematic flow chart of acquiring a first flow value according to an embodiment of the present application.

As shown in fig. 3, the method for obtaining the first flow value may include:

and S301, obtaining a pressure ratio according to the high-pressure side pressure and the low-pressure side pressure.

The pressure ratio may be a ratio of the high side pressure to the low side pressure, for example, the pressure ratio may be a ratio obtained by dividing the high side pressure by the low side pressure.

S302, obtaining a target rotating speed according to the corresponding relation among the pressure ratio, the flow value and the rotating speed, and obtaining the target guide vane opening according to the corresponding relation among the pressure ratio, the flow value and the guide vane opening.

It can be appreciated that the correspondence between the plurality of groups of pressure ratios, flow rate values and rotation speeds and the correspondence between the plurality of groups of pressure ratios, flow rate values and guide vane openings can be stored in the water chiller, so that the water chiller can obtain the corresponding target rotation speed based on the third flow rate values and the pressure ratios and obtain the corresponding target guide vane opening based on the third flow rate values and the pressure ratios. Wherein the third flow rate value may be preset. For example, the third flow rate value may be a flow rate value of the refrigerant flowing through the compressor when the chiller is operating normally.

S303, calculating a difference value between the target rotating speed and the actual rotating speed and a difference value between the opening degree of the target guide vane and the opening degree of the actual guide vane.

Wherein, the difference between the target rotation speed and the actual rotation speed may be: a difference (or an absolute value of a difference) of the target rotational speed minus the actual rotational speed, or a difference (or an absolute value of a difference) of the actual rotational speed minus the target rotational speed; the difference between the target vane opening and the actual vane opening may be: the target vane opening minus the difference (or absolute value of the difference) of the actual vane opening, or the actual vane opening minus the difference (or absolute value of the difference) of the target vane opening.

S304, judging whether the difference value between the target rotating speed and the actual rotating speed is smaller than or equal to a third threshold value, and judging whether the difference value between the opening of the target guide vane and the opening of the actual guide vane is smaller than or equal to a fourth threshold value.

Wherein when it is determined that the difference between the target rotation speed and the actual rotation speed is less than or equal to the third threshold value and the difference between the target guide vane opening and the actual guide vane opening is less than or equal to the fourth threshold value, the water chiller may perform the step shown in S305.

Alternatively, the water chiller may perform the step shown in S306 when it is determined that the difference between the target rotational speed and the actual rotational speed is greater than the third threshold value and/or the difference between the target vane opening and the actual vane opening is greater than the fourth threshold value.

S305, determining the third flow rate value as the first flow rate value.

It is understood that since the constraint relationship is satisfied between the theoretical target rotation speed corresponding to the third flow rate value and the actual rotation speed obtained by actual measurement, and the constraint relationship is satisfied between the theoretical target vane opening corresponding to the third flow rate value and the actual vane opening obtained by actual measurement, the third flow rate value can be determined as the first flow rate value of the current refrigerant flowing through the compressor.

S306, adjusting the third flow rate value to obtain an adjusted third flow rate value.

The adjusted third flow value may be used to replace the third flow value in the step shown in S302, and the steps shown in S301-S306 are continuously performed until the first flow value meeting the requirement is output.

It is understood that when the theoretical target rotation speed corresponding to the third flow rate value and the actual rotation speed obtained by actual measurement do not satisfy the constraint relationship, and/or the theoretical target guide vane opening corresponding to the third flow rate value and the actual guide vane opening obtained by actual measurement do not satisfy the constraint relationship, a deviation is generated between the third flow rate value and the current flow rate value of the refrigerant flowing through the compressor, so that the third flow rate value can be made closer to the current flow rate value of the refrigerant flowing through the compressor by adjusting the third flow rate value.

For example, when the difference obtained by subtracting the actual rotation speed from the target rotation speed is greater than or equal to a certain threshold (and/or the difference obtained by subtracting the actual rotation speed from the target guide vane opening is greater than or equal to a certain threshold), the value of the third flow value is larger, so that the third flow value can be reduced based on the target step size; or when the difference value obtained by subtracting the actual rotation speed from the target rotation speed is smaller than a certain threshold value (and/or the difference value obtained by subtracting the actual guide vane opening from the target guide vane opening is smaller than a certain threshold value), the value of the third flow rate value is smaller, so that the third flow rate value can be increased based on the target step length, and the corresponding third flow rate value when the target rotation speed and the actual rotation speed (and/or the target guide vane opening and the actual guide vane opening) are almost equal can be obtained.

In a possible implementation, when the third flow value is the volume flow, determining that the third flow value is the first flow value includes: obtaining mass flow corresponding to the third flow value according to the third flow value and the first density of the refrigerant flowing through the compressor; the mass flow is determined to be a first flow value.

The first density is obtained based on the low-pressure side pressure and the suction temperature of the compressor, which may be replaced by a superheat.

For example, the correspondence between the density, the low side pressure, and the suction temperature may be stored in the chiller. When the third flow value is the volume flow, the chiller may obtain a corresponding first density of the refrigerant based on the measured low-pressure side pressure and suction temperature, multiply the third flow value by the first density of the refrigerant to obtain a mass flow corresponding to the third flow value, and further use the mass flow corresponding to the obtained third flow value as the first flow value. The correspondence relationship among the density, the low-pressure side pressure, and the suction temperature may be collectively referred to as refrigerant properties.

It will be appreciated that, as shown in fig. 3, when the third flow rate value in the step shown in S302 is a volume flow rate, the third flow rate value in the step shown in S305 may be a mass flow rate obtained after the treatment, and the third flow rate value in the step shown in S306 and the adjusted third flow rate value may be volume flows.

Based on this, the first flow rate value of the refrigerant flowing through the compressor can be accurately output based on the constraint relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotation speed and the actual guide vane opening.

On the basis of the corresponding embodiment of fig. 2, S203 includes: a second flow value is obtained based on the high side pressure, the low side pressure, a second density of the refrigerant flowing through the restriction, a flow area of the restriction, and a flow coefficient of the restriction.

Wherein the second density is based on the high side pressure and the inlet temperature of the throttling device; the inlet temperature of the throttling device may also be replaced by the condensing outlet temperature.

It will be appreciated that the correspondence between the high side pressure, the inlet temperature of the throttling device, and the density may be stored in the chiller, such that the chiller may obtain the second density based on the actually measured high side pressure and the inlet temperature of the throttling device. The correspondence between the high-pressure side pressure, the inlet temperature of the throttle device, and the density may be referred to as refrigerant properties.

For example, the method for calculating the second flow value m may be referred to the following formula (1):

wherein C is _D May be a flow coefficient; a may be the flow area of the restriction; ρ may be a second density; p (P) ₁ May be the high side pressure; p (P) ₂ May be the low side pressure.

In a possible implementation, the flow coefficient may be obtained directly, or the flow coefficient may be obtained indirectly from the opening degree of the throttle device or the number of motor steps of the throttle device. For example, the correspondence between the flow coefficient and the opening of the throttling device may be stored in the water chiller, and when the actual opening obtained by actual measurement is obtained, the water chiller may obtain the flow coefficient corresponding to the actual opening based on the correspondence between the flow coefficient and the opening of the throttling device; or, the correspondence between the flow coefficient and the motor step number of the throttling device may be stored in the water chiller, and when the actual motor step number obtained by actual measurement is obtained, the water chiller may obtain the flow coefficient corresponding to the actual motor step number based on the correspondence between the flow coefficient and the motor step number of the throttling device.

It is understood that the method for obtaining the flow coefficient in the embodiment of the present application is not specifically limited.

Based on the above, the chiller can obtain a more accurate second flow value according to the high-pressure side pressure, the low-pressure side pressure, the second density of the refrigerant flowing through the throttling device, the flow area of the throttling device and the flow coefficient of the throttling device.

On the basis of the embodiment corresponding to fig. 2, when the number of compressors is plural and the number of throttle devices is plural, S201 includes: determining whether the refrigerant leaks based on the sum of the plurality of first flow values and the sum of the plurality of second flow values.

In one implementation, the refrigerant leak is determined when a difference between the sum of the plurality of first flow values and the sum of the plurality of second flow values is greater than or equal to a fifth threshold; alternatively, it is determined that the refrigerant is not leaked when a difference between the sum of the plurality of first flow rate values and the sum of the plurality of second flow rate values is less than a fifth threshold value.

For example, when the chiller includes the first compressor, the second compressor, the first throttling device, and the second throttling device, the chiller may calculate a sum of a flow value corresponding to the refrigerant flowing through the first compressor and a flow value corresponding to the refrigerant flowing through the second compressor, so as to obtain a sum of flow values corresponding to the compressors; the chiller may calculate a sum of the flow value corresponding to the refrigerant flowing through the first throttling device and the flow value corresponding to the refrigerant flowing through the second throttling device to obtain a sum of the flow values corresponding to the throttling devices. Further, when the difference between the sum of the flow rate values corresponding to the compressors and the sum of the flow rate values corresponding to the throttling device is greater than or equal to a fifth threshold value, the refrigerant leakage is determined.

Further, the refrigerant leakage is determined when a time when a difference between the sum of the plurality of first flow rate values and the sum of the plurality of second flow rate values is greater than or equal to a fifth threshold exceeds a certain threshold.

In another implementation, obtaining flow values corresponding to the refrigerant flowing through each compressor, calculating an average value of the flow values corresponding to each compressor, obtaining flow values corresponding to the refrigerant flowing through each throttling device, calculating an average value of the flow values corresponding to each throttling device, and determining that the refrigerant leaks when a difference value between the average value of the flow values corresponding to each compressor and the average value of the flow values corresponding to each throttling device is greater than or equal to a sixth threshold value; or determining that the refrigerant is not leaked when a difference between the average value of the flow rate values corresponding to the compressors and the average value of the flow rate values corresponding to the throttling devices is smaller than a sixth threshold value.

When the water chiller includes the first compressor, the second compressor, the first throttling device, and the second throttling device, the water chiller may calculate an average value of a flow value corresponding to the refrigerant flowing through the first compressor and a flow value corresponding to the refrigerant flowing through the second compressor, so as to obtain an average value of flow values corresponding to the compressors; the water chiller can calculate the average value of the corresponding flow value when the refrigerant flows through the first throttling device and the corresponding flow value when the refrigerant flows through the second throttling device, and the average value of the corresponding flow values of the throttling devices is obtained. Further, when the difference between the average value of the flow rate values corresponding to the compressor and the average value of the flow rate values corresponding to the throttle device is greater than or equal to the sixth threshold value, the refrigerant leakage is determined.

Further, when the time when the difference between the average value of the flow rate values corresponding to the compressors and the average value of the flow rate values corresponding to the throttling devices is greater than or equal to the sixth threshold exceeds a certain threshold, the refrigerant leakage is determined.

Based on this, even if the water chiller includes a plurality of compressors and a plurality of throttle devices, the water chiller can detect the refrigerant leakage condition based on the difference between the sum (or average) of the first flow rate values calculated by the respective compressors and the sum (or average) of the second flow rate values calculated by the respective throttle devices.

On the basis of the corresponding embodiment of fig. 2, the method further comprises the following steps: and when the refrigerant leakage is determined, sending indication information for indicating the refrigerant leakage to the electronic equipment, and carrying out refrigerant leakage prompt according to the indication information by the electronic equipment.

In an exemplary case where the cold water machine and the electronic device are in communication connection, the cold water machine can send the detected refrigerant leakage condition to the electronic device through prompt information, so that the electronic device can initiate user prompt, and the user prompt can be used for indicating a user to timely process the refrigerant leakage condition. For example, the user prompt may be a prompt interface in the electronic device, or may also be in a form of an alarm sound initiated by the electronic device, which is not limited in the embodiment of the present application.

Wherein, this electronic equipment can include: the embodiment of the application is not limited to the specific technology and the specific equipment form adopted by the electronic equipment.

Based on this, electronic equipment can in time prompt the user based on the prompt message that the cold water machine sent for the user can even perceive the condition that the refrigerant leaked, avoids influencing the work efficiency of cold water machine.

On the basis of the corresponding embodiment of fig. 2, the method further comprises the following steps: when the refrigerant leakage is determined, a preset maintenance flow is performed.

For example, a maintenance flow for refrigerant leakage may be provided in the water chiller, so that the water chiller automatically triggers the maintenance flow when detecting refrigerant leakage, thereby realizing automatic processing of refrigerant leakage detection and maintenance. The maintenance procedure may include: a down-conversion process, an automatic shutdown process, etc.

Based on the description of the above embodiments, in order to better understand the embodiments of the present application, a detailed description will be given below of an implementation procedure of the refrigerant leak detection provided in the embodiments of the present application, taking the high-side pressure as the condensing pressure, the low-side pressure as the evaporating pressure, and the throttling device as the expansion valve as an example. Fig. 4 is a schematic flow chart of another refrigerant leakage detecting method according to an embodiment of the present application.

As shown in fig. 4, the refrigerant leakage detecting method may include the steps of:

s401, under the running condition of the water chiller, data acquisition is carried out.

Wherein the data may include: the actual rotational speed of the compressor, the actual vane opening of the compressor, the suction temperature of the compressor, the evaporating pressure of the compressor, the condensing outlet temperature of the compressor, the opening of the expansion valve (or the number of motor steps of the expansion valve), and the like.

In a possible implementation manner, to avoid the influence of the measurement noise on the measurement result, the water chiller may perform noise reduction processing on the data acquired in the step shown in S401, and input the data after the noise reduction processing as the data in the steps shown in S402 and S403. The noise reduction processing may include a kalman filtering method, and the noise reduction processing method is not specifically limited in the embodiment of the present application.

S402, obtaining the theoretical flow of the compression mechanism by utilizing the corresponding relation among the flow, the pressure ratio and the rotating speed, the corresponding relation among the flow, the pressure ratio and the opening of the guide vane, the actual rotating speed, the actual opening of the guide vane, the suction temperature, the evaporation pressure, the condensation pressure and the physical property of the refrigerant.

The physical properties of the refrigerant may include: correspondence between density, evaporation pressure and suction temperature; the theoretical compressor flow may be the first flow value described in the embodiments of the present application.

It can be understood that the method for obtaining the theoretical flow rate of the compressor can refer to the method for obtaining the first flow rate value in the embodiment corresponding to fig. 3, which is not described herein.

S403, obtaining the theoretical flow of the expansion valve by utilizing the evaporation pressure, the condensation outlet temperature, the opening degree of the expansion valve (or the motor step number of the expansion valve) and the physical property of the refrigerant.

The physical properties of the refrigerant may further include: correspondence between high side pressure, condensation outlet temperature, and density; the theoretical compressor flow may be the second flow value described in the embodiments of the present application.

It can be understood that the method for obtaining the theoretical flow of the expansion valve can be referred to the method for obtaining the second flow value in the formula (1), and will not be described herein.

S404, calculating flow deviation.

The flow deviation may be a difference between the theoretical flow of the compression mechanism and the theoretical flow of the expansion valve.

In a possible implementation, when the number of compressors is plural and the number of expansion valves is plural, the flow deviation may be a difference between a sum of theoretical flows of each compression mechanism and a sum of theoretical flows of each expansion valve.

S405, judging that the absolute value of the flow deviation is larger than or equal to theta, and the time when the absolute value of the flow deviation is larger than or equal to theta is larger than the set time.

Wherein, when the absolute value of the flow deviation is greater than or equal to θ and the time when the absolute value of the flow deviation is greater than or equal to θ is greater than the set time, the steps shown in S406-S407 are performed. And when the absolute value of the flow deviation is smaller than theta and/or the absolute value of the flow deviation is larger than or equal to theta and smaller than or equal to the set time, the water chiller normally operates and the flow of refrigerant leakage detection is continuously executed.

In a possible implementation, when the number of compressors is plural and the number of expansion valves is plural, the value of θ may be different, for example, the value of θ may be related to the number of compressors (or the number of expansion valves). For example, when the number of compressors and expansion valves is 1, the threshold value for judging the flow rate deviation may be θ, and when the number of compressors and expansion valves is 2, the threshold value for judging the flow rate deviation may be 2θ.

S406, determining the refrigerant leakage level.

S407, determining maintenance response.

For example, the chiller may perform a maintenance procedure corresponding to the refrigerant leakage level.

Based on this, the chiller can carry out accurate detection to the refrigerant leakage condition based on compressor theoretical flow and expansion valve theoretical flow to adopt the numerical value of conventional measurement to carry out refrigerant leakage detection, can increase the convenience of implementation.

On the basis of the above embodiment, fig. 5 is a schematic structural diagram of a water chiller 500 according to an embodiment of the present application. As shown in fig. 5, the water chiller 500 includes: a processor 501, and a memory 502.

Wherein the memory 502 is for storing a computer program; the processor 501 is configured to execute a computer program stored in a memory to implement the refrigerant leak detection method in the above-described method embodiments.

In an embodiment of the present application, the memory 502 and the processor 501 are electrically connected directly or indirectly to implement data transmission or interaction. For example, the elements may be electrically coupled to each other via one or more communication buses or signal lines, such as bus 503. The memory 502 stores therein computer-executable instructions for implementing a data access control method, including at least one software functional module that may be stored in the memory in the form of software or firmware, and the processor 501 executes various functional applications and data processing by running the software programs and modules stored in the memory.

The Memory 502 may be, but is not limited to, random access Memory (Random Access Memory, RAM), read Only Memory (ROM), programmable Read Only Memory (Programmable Read-Only Memory, PROM), erasable Read Only Memory (Erasable Programmable Read-Only Memory, EPROM), electrically erasable Read Only Memory (Electric Erasable Programmable Read-Only Memory, EEPROM), etc. The memory is used for storing a program, and the processor executes the program after receiving the execution instruction. Further, the software programs and modules within the memory may also include an operating system, which may include various software components and/or drivers for managing system tasks (e.g., memory management, storage device control, power management, etc.), and may communicate with various hardware or software components to provide an operating environment for other software components.

The processor 501 may be an integrated circuit chip with signal processing capability, and the processor 501 may be a general-purpose processor including a central processing unit (cpu), a network processor (Network Processor, referred to as NP), and the like. The disclosed methods, steps, and logic blocks in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

It should be noted that, the water chiller provided in this embodiment may be used to execute the above-mentioned refrigerant leakage detection method, and its implementation manner and technical effects are similar, and this embodiment is not repeated here.

The steps of the method disclosed in connection with the embodiments of the present application may be embodied directly in the execution of a hardware decoding processor, or in the execution of a combination of hardware and software modules in a decoding processor. The software modules may be located in a random access memory, flash memory, read only memory, programmable read only memory, or electrically erasable programmable memory, registers, etc. as well known in the art. The storage medium is located in a memory, and the processor reads the information in the memory and, in combination with its hardware, performs the steps of the above method.

The embodiment of the application also provides a refrigerant leakage detection device. Fig. 6 is a schematic structural diagram of a refrigerant leakage detecting device 600 according to an embodiment of the present application, and as shown in fig. 6, the refrigerant leakage detecting device 600 may include: an acquisition module 601 and a determination module 602.

Specifically, the acquiring module 601 is configured to acquire a high-pressure side pressure of the compressor, a low-pressure side pressure of the compressor, an actual rotation speed of the compressor, and an actual guide vane opening of the compressor; the determining module 602 is configured to obtain a first flow value of the refrigerant flowing through the compressor according to a constraint relationship among the high-pressure side pressure, the low-pressure side pressure, the actual rotational speed, and the actual guide vane opening; the acquisition module 601 is further configured to acquire a second flow value of the refrigerant flowing through the throttling device; the throttling device is arranged between the condenser and the evaporator; the determining module 602 is further configured to determine whether the refrigerant leaks according to the first flow value and the second flow value.

In some embodiments, the determining module 602 is specifically configured to: determining that the refrigerant leaks when the difference between the first flow value and the second flow value is greater than or equal to a first threshold value; alternatively, it is determined that the refrigerant is not leaked when the difference between the first flow value and the second flow value is less than the first threshold value.

In some embodiments, the determining module 602 is specifically configured to: the refrigerant leak is determined when the time when the difference between the first flow value and the second flow value is greater than or equal to the first threshold exceeds the second threshold.

In some embodiments, the determining module 602 is specifically configured to: obtaining a target rotating speed and a target guide vane opening according to a third flow value preset by the compressor and the ratio of the high-pressure side pressure to the low-pressure side pressure; wherein, the third flow rate value, the ratio and the target rotating speed have a corresponding relation; the third flow rate value, the ratio and the opening degree of the target guide vane have a corresponding relation; and when the difference value between the target rotating speed and the actual rotating speed is smaller than or equal to a third threshold value and the difference value between the opening of the target guide vane and the opening of the actual guide vane is smaller than or equal to a fourth threshold value, determining the third flow value as the first flow value.

In some embodiments, the determining module 602 is specifically configured to: when the difference value between the target rotating speed and the actual rotating speed is larger than a third threshold value and/or the difference value between the opening of the target guide vane and the opening of the actual guide vane is larger than a fourth threshold value, the third flow value is adjusted, and the adjusted third flow value is obtained; and obtaining the target rotating speed and the target guide vane opening according to the adjusted third flow value and the ratio of the high-pressure side pressure to the low-pressure side pressure.

In some embodiments, the determining module 602 is specifically configured to: obtaining mass flow corresponding to the third flow value according to the third flow value and the first density of the refrigerant flowing through the compressor; wherein the first density is based on the low side pressure and a suction temperature of the compressor; the mass flow is determined to be a first flow value.

In some embodiments, the obtaining module 601 is specifically configured to: acquiring a second flow rate value of the refrigerant flowing through the throttling device, comprising: obtaining a second flow value according to the high-pressure side pressure, the low-pressure side pressure, the second density of the refrigerant flowing through the throttling device, the flow area of the throttling device and the flow coefficient of the throttling device; wherein the second density is based on the high side pressure and the inlet temperature of the throttling device.

In some embodiments, the number of compressors is multiple, the number of throttles is multiple, and the determining module 602 is specifically configured to: determining whether the refrigerant leaks based on the sum of the plurality of first flow values and the sum of the plurality of second flow values.

In some embodiments, the determining module 602 is specifically configured to: determining whether the refrigerant is leaking based on the sum of the plurality of first flow values and the sum of the plurality of second flow values, comprising: determining that the refrigerant leaks when the difference between the sum of the plurality of first flow values and the sum of the plurality of second flow values is greater than or equal to a fifth threshold; alternatively, it is determined that the refrigerant is not leaked when a difference between the sum of the plurality of first flow rate values and the sum of the plurality of second flow rate values is less than a fifth threshold.

In some embodiments, the determining module 602 is specifically configured to: executing a preset maintenance flow when determining that the refrigerant leaks; the maintenance flow comprises the following steps: a down-conversion process, or an automatic shutdown process.

In some embodiments, the refrigerant leak detection apparatus 600 further includes: and the communication module is used for sending indication information for indicating the refrigerant leakage to the electronic equipment when the refrigerant leakage is determined, and is used for prompting the refrigerant leakage according to the indication information by the electronic equipment.

In some embodiments, when the throttle device is plural, the plural throttle devices are disposed in parallel between the condenser and the evaporator.

In some optional embodiments, the refrigerant leak detection device 600 may further include a storage module for storing data and/or instructions, and the refrigerant leak detection device provided in this embodiment (e.g. the acquisition module 601 and the determination module 602 described above) may be used to read the data and instructions in the storage module, so as to implement the refrigerant leak detection method described above, and its implementation manner and technical effects are similar, which are not repeated herein.

It should be noted that, the acquisition module 601 in each of the above embodiments may be a receiver when actually implemented, and is configured to receive information sent by other devices or measurement units, for example, receive the high-pressure side pressure of the compressor, the low-pressure side pressure of the compressor, the actual rotation speed of the compressor, and the actual vane opening of the compressor. The acquisition module 601 may be implemented through a communication port.

In some alternative embodiments, the determining module 602 may be implemented in software, which is invoked by a processing element, or may be implemented in hardware. For example, the determination module 602 may be a separate processing element, or may be integrated into a chip of the refrigerant leak detection device. In addition, the program code may be stored in a memory module of the refrigerant leakage detecting device 600, and a certain processing element of the refrigerant leakage detecting device 600 may call and execute part or all of the functions of the determining module 602.

Furthermore, all or part of these processing elements may be integrated together or may be implemented separately. The module may be an integrated circuit with signal processing capabilities. In implementation, each step of the above method or each module above may be implemented by an integrated logic circuit of hardware in a processor element or an instruction in a software form.

For example, the above modules may be one or more integrated circuits configured to implement the above refrigerant leak detection method. Such as one or more application specific integrated circuits (application specific integrated circuit, ASIC), or one or more microprocessors (digital signal processor, DSP), or one or more field programmable gate arrays (field programmable gate array, FPGA), or the like. For another example, when some of the above modules are implemented in the form of processing element scheduler code, the processing elements may be the same processor, such as a central processing unit (Central Processing Unit, CPU) or other processor that may invoke the program code. As another example, these modules may be integrated together and implemented in a system-on-a-chip.

The embodiment of the application also provides a computer readable storage medium, wherein computer executable instructions are stored in the computer readable storage medium, and the computer executable instructions are used for realizing the method of any embodiment when being executed by a processor.

The methods described in the above embodiments may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. Computer readable media can include computer storage media and communication media and can include any medium that can transfer a computer program from one place to another. The storage media may be any target media that is accessible by a computer.

As one possible design, the computer-readable medium may include compact disk read-only memory (CD-ROM), RAM, ROM, EEPROM, or other optical disk memory; the computer readable medium may include disk storage or other disk storage devices. Moreover, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, digital versatile disc (digital versatile disc, DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

Fig. 7 is a schematic diagram of a refrigerant leakage detecting system 700 according to an embodiment of the application. In the embodiment corresponding to fig. 7, an electronic device is taken as a tablet computer for example and is illustrated.

As shown in fig. 7, the refrigerant leak detection system 700 may include: chiller 701 and electronic device 702. In the case where the water chiller 701 is connected to the electronic device 702, after the step of acquiring the high-pressure side pressure of the compressor, the low-pressure side pressure of the compressor, the actual rotation speed of the compressor, and the actual guide vane opening of the compressor, the processor in the water chiller 701 transmits the high-pressure side pressure, the low-pressure side pressure, the actual rotation speed, and the actual guide vane opening to the electronic device 702; the electronic equipment 702 obtains a high-pressure side pressure, a low-pressure side pressure, an actual rotating speed and an actual guide vane opening degree from the water chiller 701, and the electronic equipment 702 obtains a first flow value of the refrigerant flowing through the compressor according to the restriction relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening degree; the electronics 702 acquire a second flow value of the refrigerant flowing through the restriction; the electronics 702 determine whether the refrigerant is leaking based on the first flow value and the second flow value.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present invention, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present invention, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

While embodiments of the present invention have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the invention, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the invention.

Claims

1. A method of refrigerant leak detection, the method comprising:

Acquiring a high-pressure side pressure of a compressor, a low-pressure side pressure of the compressor, an actual rotating speed of the compressor and an actual guide vane opening of the compressor;

obtaining a first flow value of the refrigerant flowing through the compressor according to the restriction relation among the high-pressure side pressure, the low-pressure side pressure, the actual rotating speed and the actual guide vane opening;

acquiring a second flow value of the refrigerant flowing through the throttling device; the throttling device is arranged between the condenser and the evaporator;

and determining whether the refrigerant leaks according to the first flow value and the second flow value.

2. The method of claim 1, wherein said determining whether said refrigerant is leaking based on said first flow value and said second flow value comprises:

determining that the refrigerant leaks when the difference between the first flow value and the second flow value is greater than or equal to a first threshold;

alternatively, the refrigerant is determined not to leak when the difference between the first flow value and the second flow value is less than the first threshold.

3. The method of claim 2, wherein the determining the refrigerant leak when the difference between the first flow value and the second flow value is greater than or equal to a first threshold value comprises:

And determining that the refrigerant leaks when the time when the difference between the first flow value and the second flow value is greater than or equal to a first threshold exceeds a second threshold.

4. The method of claim 3, wherein said deriving a first flow value of said refrigerant through said compressor based on constraints among said high side pressure, said low side pressure, said actual rotational speed, and said actual vane opening comprises:

obtaining a target rotating speed and a target guide vane opening according to a third flow value preset by the compressor and the ratio of the high side pressure to the low side pressure; wherein, the third flow rate value, the ratio and the target rotating speed have a corresponding relation; the third flow rate value, the ratio and the target guide vane opening have a corresponding relation;

and when the difference value between the target rotating speed and the actual rotating speed is smaller than or equal to a third threshold value, and the difference value between the target guide vane opening and the actual guide vane opening is smaller than or equal to a fourth threshold value, determining that the third flow value is the first flow value.

5. The method according to claim 4, wherein the method further comprises:

When the difference value between the target rotating speed and the actual rotating speed is larger than the third threshold value, and/or the difference value between the target guide vane opening and the actual guide vane opening is larger than the fourth threshold value, the third flow rate value is adjusted, and an adjusted third flow rate value is obtained;

the obtaining a target rotation speed and a target guide vane opening according to a third flow value preset by the compressor and a ratio of the high side pressure to the low side pressure comprises: and obtaining the target rotating speed and the target guide vane opening according to the adjusted third flow value and the ratio of the high side pressure to the low side pressure.

6. The method of claim 4, wherein the third flow value is a volumetric flow rate, and wherein the determining the third flow value is the first flow value comprises:

obtaining a mass flow corresponding to the third flow value according to the third flow value and the first density of the refrigerant flowing through the compressor; wherein the first density is derived based on the low side pressure and a suction temperature of the compressor;

And determining the mass flow as the first flow value.

7. The method of claim 6, wherein said obtaining a second flow value of said refrigerant through a throttling device comprises:

obtaining the second flow value according to the high side pressure, the low side pressure, a second density of the refrigerant flowing through the throttling device, a flow area of the throttling device and a flow coefficient of the throttling device; wherein the second density is based on the high side pressure and an inlet temperature of the throttling device.

8. The method of claim 1, wherein the number of compressors is a plurality and the number of throttles is a plurality, the determining whether the refrigerant is leaking based on the first flow value and the second flow value comprising:

determining whether the refrigerant leaks based on a sum of the plurality of first flow values and a sum of the plurality of second flow values.

9. The method of claim 8, wherein said determining whether said refrigerant is leaking based on a sum of a plurality of said first flow values and a sum of a plurality of said second flow values comprises:

Determining that the refrigerant leaks when a difference between a sum of the plurality of the first flow values and a sum of the plurality of the second flow values is greater than or equal to a fifth threshold;

alternatively, when a difference between the sum of the plurality of the first flow rate values and the sum of the plurality of the second flow rate values is smaller than the fifth threshold value, it is determined that the refrigerant is not leaked.

10. The method according to claim 1, wherein the method further comprises:

executing a preset maintenance flow when the refrigerant leakage is determined; wherein, the maintenance flow includes: a down-conversion process, or an automatic shutdown process.

11. The method according to claim 1, wherein the method further comprises:

and when the refrigerant leakage is determined, sending indication information for indicating the refrigerant leakage to the electronic equipment, and carrying out refrigerant leakage prompt according to the indication information by the electronic equipment.

12. The method of claim 1, wherein when the throttle device is plural, plural throttle devices are disposed in parallel between the condenser and the evaporator.

13. A water chiller, characterized in that it is adapted to perform the method according to any one of claims 1-13.

14. An electronic device comprising a processor configured to perform the method of any of claims 1-12.

15. A computer readable storage medium, characterized in that the storage medium stores a computer program which, when executed by a processor, implements the method according to any of claims 1-12.