Low-temperature refrigeration device, control method, controller, and storage medium

Abstract

The embodiment of the present application provides a kind of low-temperature refrigeration device, control method, controller and storage medium, wherein, device includes: evaporator, compressor, solenoid valve and first microchannel heat exchanger connected in turn, first microchannel heat exchanger is connected with second check valve through first check valve, compressor is connected with second microchannel heat exchanger, second microchannel heat exchanger is connected with second check valve through flow regulating valve, second check valve, liquid storage tank and expansion valve are connected in turn, expansion valve is connected with evaporator, low pressure sensor is arranged between evaporator and compressor, first microchannel heat exchanger is configured with first temperature sensor, second microchannel heat exchanger is configured with second temperature sensor, the inlet of second check valve is configured with high pressure sensor, low pressure sensor, solenoid valve, first temperature sensor, second temperature sensor, flow regulating valve and outdoor fan are electrically connected with controller.The present application improves the operation reliability of refrigeration device in low-temperature environment.

Description

Technical Field

[0001] This invention relates to the field of refrigeration equipment technology, and in particular to a cryogenic refrigeration device, control method, controller and storage medium. Background Technology

[0002] Existing cryogenic refrigeration devices reduce the heat exchange area of ​​the staged condenser by blocking a section of the heat exchange pipe in the staged condenser, thereby increasing the condensing pressure in the pipe and establishing a condensing pressure difference on both sides of the compressor at low temperatures, enabling the compressor to start and operate at low temperatures.

[0003] However, because the refrigerant shrinks in volume at low temperatures, the refrigerant volume within the refrigeration unit decreases, leading to a drop in condensing pressure within the piping. Simultaneously, when the outdoor temperature is below the minimum operating temperature of the cryogenic refrigeration unit, the heat dissipation efficiency of the condensing pipes accelerates, making it impossible to maintain the condensing pressure for an extended period. Therefore, existing cryogenic refrigeration units cannot stably establish the condensing pressure differential measured by the compressor, resulting in reduced compressor start-up and operational reliability. This, in turn, reduces the operational reliability of the cryogenic refrigeration unit in low-temperature environments. Summary of the Invention

[0004] The purpose of this invention is to provide a cryogenic refrigeration device, a control method, a controller, and a storage medium to improve the operational reliability of the refrigeration device in low-temperature environments. The specific technical solution is as follows:

[0005] A cryogenic refrigeration device, the cryogenic refrigeration device comprising:

[0006] The system comprises an evaporator (1), a low-pressure sensor (2), a compressor (3), a solenoid valve (4), a first microchannel heat exchanger (5), a second microchannel heat exchanger (6), a first temperature sensor (7), a second temperature sensor (8), a flow regulating valve (9), a first check valve (10), a high-pressure sensor (11), a second check valve (12), a liquid storage tank (13), an expansion valve (14), a controller (15), and an outdoor fan (16). The outlet of the evaporator (1) is connected to the inlet of the compressor (3). The outlet of the compressor (3) is connected to the inlet of the first microchannel heat exchanger (5) via the solenoid valve (4). The outlet of the first microchannel heat exchanger (5) is connected to the inlet of the first check valve (10). The outlet of the first check valve (10) is connected to the inlet of the second check valve (12). The outlet of the compressor (3) is connected to the inlet of the second microchannel heat exchanger (6). The outlet of the second microchannel heat exchanger (6) is connected to the inlet of the flow regulating valve (9). The outlet of the flow regulating valve (9) is connected to the inlet of the second check valve (12), the outlet of the second check valve (12) is connected to the inlet of the liquid storage tank (13), the outlet of the liquid storage tank (13) is connected to the inlet of the expansion valve (14), the outlet of the expansion valve (14) is connected to the inlet of the evaporator (1), the low pressure sensor (2) is located between the outlet of the evaporator (1) and the inlet of the compressor (3), the first microchannel heat exchanger (5) is equipped with the first temperature sensor (7), the second microchannel heat exchanger (6) is equipped with the second temperature sensor (8), the inlet of the second check valve (12) is equipped with the high pressure sensor (11), and the low pressure sensor (2), the solenoid valve (4), the first temperature sensor (7), the second temperature sensor (8), the flow regulating valve (9), the high pressure sensor (11) and the outdoor fan (16) are all electrically connected to the controller (15).

[0007] Optionally, the solenoid valve (4) is a normally open solenoid valve.

[0008] Optionally, the cryogenic refrigeration device may further include an indoor fan.

[0009] A control method for a cryogenic refrigeration device, the control method being applied to a controller (15) in any of the cryogenic refrigeration devices described above, the control method comprising:

[0010] After the cryogenic refrigeration device is powered on and running, the first pressure value collected by the high-pressure sensor (11) at each operating moment is monitored, and a control strategy corresponding to the first pressure value is executed according to the magnitude of the first pressure value, wherein the control strategy includes:

[0011] When the first pressure value is detected to be within the first preset pressure range, the solenoid valve (4) is controlled to be closed and the flow regulating valve (9) is controlled to be fully open, and the maximum value of the first preset pressure range is less than the first preset pressure threshold.

[0012] When the first pressure value is detected to be within the second preset pressure range, the solenoid valve (4) is controlled to be in the open state, and the opening of the flow regulating valve (9) is adjusted according to the current condensing temperature difference value. The minimum value of the second preset pressure range is the second preset pressure threshold, the maximum value of the second preset pressure range is less than the third preset pressure threshold, the first preset pressure threshold is less than the second preset pressure threshold, and the current condensing temperature difference value is the difference between the temperatures collected by the first temperature sensor (7) and the second temperature sensor (8) at the current operating time.

[0013] Optionally, adjusting the opening of the flow regulating valve (9) according to the current condensation temperature difference includes:

[0014] Determine whether the current condensing temperature difference is within the preset temperature difference range. If so, find the opening value corresponding to the current condensing temperature difference in the preset opening control table and determine it as the target regulating valve opening value. Adjust the opening of the flow regulating valve (9) to the target regulating valve opening value.

[0015] When the current condensation temperature difference is not less than the maximum value of the preset temperature difference range, the minimum opening value in the preset opening control table is updated to the target regulating valve opening value, and the opening of the flow regulating valve (9) is adjusted to the target regulating valve opening value.

[0016] Optionally, when the first pressure value is detected to be within the second preset pressure range, the method further includes:

[0017] Determine whether the first pressure value is consistent with the minimum value of the preset fan control range. If so, control the outdoor fan (16) to start running with the minimum speed in the preset fan speed table as the target speed.

[0018] When the first pressure value is greater than the minimum value of the preset fan control range, the speed corresponding to the first pressure value in the preset fan speed table is updated to the target speed, and the outdoor fan (16) is controlled to start running at the target speed.

[0019] Optionally, the method further includes:

[0020] When the second pressure value collected by the low-pressure sensor (2) is not greater than the preset alarm pressure threshold, the compressor (3) is controlled to perform a shutdown protection action and an alarm message is sent to the preset monitoring system.

[0021] Optionally, when the first pressure value is less than the minimum value of the preset fan control range, the method further includes:

[0022] When the outdoor fan (16) is in operation and the first pressure value is detected to be less than the minimum value of the preset fan control range, the outdoor fan (16) is controlled to perform a preset delayed shutdown operation.

[0023] A controller, the controller comprising:

[0024] processor;

[0025] Memory used to store the processor's executable instructions;

[0026] The processor is configured to execute the instructions to implement the control method of the cryogenic refrigeration device as described above.

[0027] A computer-readable storage medium, when the instructions in the computer-readable storage medium are executed by a processor of a controller, enables the controller to perform a control method for a cryogenic refrigeration device as described above.

[0028] This invention provides a cryogenic refrigeration device, control method, controller, and storage medium. By configuring a solenoid valve in the first microchannel heat exchanger, the valve closes when the outdoor ambient temperature is below the minimum operating temperature, reducing refrigerant flow to the outdoor side and increasing the amount of refrigerant in the indoor piping. This establishes a condensing pressure differential, thereby ensuring reliable compressor operation. Simultaneously, by using a microchannel heat exchanger as the condenser, its small internal volume increases the proportion of refrigerant volume in the condenser when the refrigerant volume decreases. This increases the pressure of the cooled refrigerant, establishing a condensing pressure differential suitable for compressor operation, thus ensuring reliable compressor operation. Finally, by configuring the solenoid valve and a first one-way valve, the refrigerant flow to the first microchannel heat exchanger can be completely cut off at low temperatures. This reduces refrigerant flow to the outdoor side, increases the amount of refrigerant in the indoor piping, and establishes a stable pressure differential. Therefore, this invention achieves its objective of improving the operational reliability of refrigeration devices in low-temperature environments.

[0029] Of course, any product or method implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of a cryogenic refrigeration device provided in an embodiment of the present invention;

[0032] Figure 2 A flowchart of a control method for a cryogenic refrigeration device is provided as an optional embodiment of the present invention;

[0033] Figure 3 A schematic diagram showing the correspondence between condensation temperature difference and target regulating valve opening value is provided as another optional embodiment of the present invention;

[0034] Figure 4 A schematic diagram showing the correspondence between a first pressure value and the outdoor fan speed, provided as another optional embodiment of the present invention;

[0035] Figure 5 A block diagram of a controller provided for another alternative embodiment of the present invention. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0037] This invention provides a cryogenic refrigeration device, such as... Figure 1 As shown, the cryogenic refrigeration device includes:

[0038] The system includes an evaporator (1), a low-pressure sensor (2), a compressor (3), a solenoid valve (4), a first microchannel heat exchanger (5), a second microchannel heat exchanger (6), a first temperature sensor (7), a second temperature sensor (8), a flow regulating valve (9), a first check valve (10), a high-pressure sensor (11), a second check valve (12), a liquid storage tank (13), an expansion valve (14), a controller (15), and an outdoor fan (16). The outlet of the evaporator (1) is connected to the inlet of the compressor (3). The outlet of the compressor (3) is connected to the inlet of the first microchannel heat exchanger (5) via the solenoid valve (4). The outlet of the first microchannel heat exchanger (5) is connected to the inlet of the first check valve (10). The outlet of the first check valve (10) is connected to the inlet of the second check valve (12). The outlet of the compressor (3) is connected to the inlet of the second microchannel heat exchanger (6). The outlet is connected to the inlet of the flow regulating valve (9), the outlet of the flow regulating valve (9) is connected to the inlet of the second check valve (12), the outlet of the second check valve (12) is connected to the inlet of the liquid storage tank (13), the outlet of the liquid storage tank (13) is connected to the inlet of the expansion valve (14), the outlet of the expansion valve (14) is connected to the inlet of the evaporator (1), the low pressure sensor (2) is located between the outlet of the evaporator (1) and the inlet of the compressor (3), the first microchannel heat exchanger (5) is equipped with the first temperature sensor (7), the second microchannel heat exchanger (6) is equipped with the second temperature sensor (8), the inlet of the second check valve (12) is equipped with the high pressure sensor (11), the low pressure sensor (2), the solenoid valve (4), the first temperature sensor (7), the second temperature sensor (8), the flow regulating valve (9), the high pressure sensor (11) and the outdoor fan (16) are all electrically connected to the controller (15).

[0039] The evaporator (1) is a device that exchanges heat with the outside air, causing the refrigerant in a low-temperature, low-pressure wet vapor state to absorb heat and become a low-temperature, low-pressure gaseous refrigerant. The compressor (3) is a device used to compress the low-temperature, low-pressure gaseous refrigerant, making it a high-temperature, high-pressure refrigerant gas.

[0040] It should be noted that the solenoid valve (4) is used to cut off the flow of refrigerant in the first microchannel heat exchanger (5) at low temperatures. When the ambient temperature is lower than the minimum operating temperature of a conventional refrigeration unit, such as when the outdoor temperature is between -15°C and -40°C, the refrigerant dissipates heat more rapidly, causing the refrigerant in the pipeline to migrate to the outdoor condenser. This results in the indoor side lacking refrigerant and unable to establish the pressure differential required for compressor operation, thus preventing the compressor from operating normally. Therefore, this invention configures the solenoid valve (4) in the first microchannel heat exchanger (5) to close the solenoid valve (4) when the outdoor ambient temperature is lower than the minimum operating temperature, reducing the flow of refrigerant to the outdoor side and increasing the amount of refrigerant in the indoor pipeline. This establishes the condensing pressure differential, thereby enabling reliable operation of the compressor (3).

[0041] It should be noted that the first microchannel heat exchanger (5) and the second microchannel heat exchanger (6) mentioned above refer to heat exchangers with a channel equivalent diameter of 10 to 1000 μm. Because the volume of the refrigerant decreases at low temperatures, and in existing refrigeration devices, the refrigerant volume in the condenser decreases as the refrigerant volume decreases due to the large internal volume of the condenser, the proportion of the refrigerant volume in the condenser becomes smaller. At this time, the increased heat exchange efficiency causes the already reduced volume of the refrigerant in the condenser to liquefy due to cooling, resulting in a decrease in pressure and thus preventing the establishment of a condensing pressure differential. Therefore, this invention uses a microchannel heat exchanger as the condenser, taking advantage of its small internal volume to increase the proportion of the refrigerant volume in the condenser when the refrigerant volume decreases. This increases the pressure of the cooled refrigerant, establishing a condensing pressure differential suitable for the compressor (3) to operate. This, in turn, enables the reliable operation of the compressor (3).

[0042] It should be noted that the aforementioned first check valve (10) is a check valve used to prevent refrigerant from flowing from the outlet of the second microchannel heat exchanger (6) into the first microchannel heat exchanger (5) via the outlet of the first microchannel heat exchanger (5). Through the aforementioned solenoid valve (4) and the first check valve (10), the refrigerant flow to the first microchannel heat exchanger (5) can be completely cut off at low temperatures. This reduces the flow of refrigerant to the outdoor side and increases the amount of refrigerant in the indoor piping.

[0043] Optionally, in one alternative embodiment of the present invention, due to the obstruction of the refrigerant by the solenoid valve (4) and the first one-way valve (10), the amount of refrigerant in the first microchannel heat exchanger (5) is lower than that in the second microchannel heat exchanger (6) under normal operating conditions. This results in a decrease in the heat exchange area utilization rate of the first microchannel heat exchanger (5) due to uneven distribution of refrigerant. At the same time, it will increase the refrigerant pressure discharged from the microchannel heat exchanger at normal operating conditions, thereby increasing the power consumption of the compressor (3) under normal operating conditions. Therefore, the present invention sets a first temperature sensor (7) and a second temperature sensor (8) to detect the condensing temperature of the two microchannel heat exchangers respectively, and controls the opening of the flow regulating valve (9) based on their respective condensing temperatures, thereby balancing the refrigerant flow of the two microchannel heat exchangers and reducing the power consumption of the compressor (3) under normal operating conditions.

[0044] Optionally, in an alternative embodiment of the present invention, the high-pressure sensor (11) and the low-pressure sensor (2) can be sensors used to collect the refrigerant pressure in the high-pressure and low-pressure side pipes of the indoor system. It should be noted that, in practical applications, the pipe pressure collected by the low-pressure sensor (2) varies with the pipe pressure collected by the high-pressure sensor (11), and data from either pressure sensor can be selected during control. However, to avoid the risk of inaccurate data due to sensor malfunction or other reasons, the present invention improves the accuracy of control by configuring the high-pressure sensor (11) and the low-pressure sensor (2) and comparing the values ​​collected by the two sensors before control.

[0045] It should be noted that the second check valve (12) is a check valve used to prevent backflow of refrigerant in the liquid storage tank (13) due to the decrease in refrigerant pressure discharged from the microchannel heat exchanger.

[0046] Optionally, in another alternative embodiment of the present invention, the expansion valve (14) is a device for throttling medium-temperature, high-pressure liquid refrigerant, converting the refrigerant into low-temperature, low-pressure wet steam. The flow rate of the expansion valve (14) can be adjusted according to the superheat of the evaporator (1). It should be noted that the expansion valve (14) can be either an electronic expansion valve or a non-electronic expansion valve. However, in the case where the expansion valve (14) is a non-electronic expansion valve, since the non-electronic expansion valve does not have an on / off function, a normally open solenoid valve needs to be configured between the outlet of the liquid storage tank (13) and the inlet of the expansion valve (14) to achieve on / off control of the pipeline.

[0047] It should be noted that in practical application scenarios, the above-mentioned... Figure 1 The specific models of each device or apparatus in the cryogenic refrigeration device shown can be set according to the actual application scenario. This invention does not impose excessive limitations or elaborate on their specific models or types.

[0048] This invention utilizes a solenoid valve configured in the first microchannel heat exchanger. When the outdoor ambient temperature is below the minimum operating temperature, the solenoid valve closes, reducing refrigerant flow to the outdoor side and increasing the amount of refrigerant in the indoor piping. This establishes a condensing pressure differential, thereby ensuring reliable compressor operation. Simultaneously, by employing a microchannel heat exchanger as the condenser, its small internal volume increases the proportion of refrigerant volume in the condenser as the refrigerant volume decreases. This increases the pressure of the cooled refrigerant, establishing a condensing pressure differential sufficient for compressor operation, thus ensuring reliable compressor operation. Finally, by configuring the solenoid valve and the first one-way valve, the refrigerant flow to the first microchannel heat exchanger can be completely cut off at low temperatures. This further reduces refrigerant flow to the outdoor side, increases the amount of refrigerant in the indoor piping, and establishes a stable pressure differential. Therefore, this invention achieves its objective of improving the operational reliability of refrigeration devices in low-temperature environments.

[0049] Optionally, the above are as follows: Figure 1 In the cryogenic refrigeration device shown, the solenoid valve (4) is a normally open solenoid valve.

[0050] Those skilled in the art will understand that for pipelines that do not need to be shut off for extended periods, the solenoid valves used should be normally open solenoid valves to reduce energy consumption.

[0051] Optionally, the above are as follows: Figure 1 The low-temperature refrigeration device shown also includes an indoor fan.

[0052] It should be noted that the above-mentioned indoor fan is a device used to guide indoor hot air to the evaporator (1).

[0053] Corresponding to the above-described device embodiments, the present invention also provides a control method for a cryogenic refrigeration device, which is applied to the above-described... Figure 1 The controller (15) in the cryogenic refrigeration device shown is, for example Figure 2 As shown, the control method includes:

[0054] S201. After the cryogenic refrigeration unit is powered on and running, the first pressure value collected by the high-pressure sensor (11) at each operating moment is monitored, and a control strategy corresponding to the value is executed according to the magnitude of the first pressure value. The control strategy includes:

[0055] S202. When the first pressure value is detected to be within the first preset pressure range, the solenoid valve (4) is controlled to be closed and the flow regulating valve (9) is controlled to be fully open, and the maximum value of the first preset pressure range is less than the first preset pressure threshold.

[0056] Optionally, in an alternative embodiment of the present invention, the first preset pressure threshold may be as described above. Figure 1 The closing pressure value of the solenoid valve (4) in the cryogenic refrigeration device shown.

[0057] S203. When the first pressure value is detected to be within the second preset pressure range, the control solenoid valve (4) is in the open state, and the opening of the flow regulating valve (9) is adjusted according to the current condensing temperature difference. The minimum value of the second preset pressure range is the second preset pressure threshold, the maximum value of the second preset pressure range is less than the third preset pressure threshold, the first preset pressure threshold is less than the second preset pressure threshold, and the current condensing temperature difference is the difference between the temperatures collected by the first temperature sensor (7) and the second temperature sensor (8) at the current operating time.

[0058] Optionally, in one alternative embodiment of the present invention, the second preset pressure threshold may be the opening pressure value of the solenoid valve (4).

[0059] Optionally, in the above as follows Figure 2 In step S203, if the first pressure value is detected to be within the second preset pressure range, the solenoid valve (4) is in the closed state. To ensure that the collected first pressure value is a stable value, thereby improving the subsequent control accuracy, the solenoid valve (4) can be set to open after a delay when the first pressure value is equal to the second preset pressure threshold.

[0060] Optionally, in another alternative embodiment of the present invention, the aforementioned third preset pressure threshold may be as described above. Figure 1 The maximum design condensing pressure value of the cryogenic refrigeration device shown.

[0061] Optionally, the opening of the flow regulating valve (9) can be adjusted according to the current condensing temperature difference, including:

[0062] Determine whether the current condensing temperature difference is within the preset temperature difference range. If so, find the opening value corresponding to the current condensing temperature difference in the preset opening control table and determine it as the target regulating valve opening value. Adjust the opening of the flow regulating valve (9) to the target regulating valve opening value.

[0063] When the current condensation temperature difference is not less than the maximum value of the preset temperature difference range, the minimum opening value in the preset opening control table is updated to the target regulating valve opening value, and the opening of the flow regulating valve (9) is adjusted to the target regulating valve opening value.

[0064] Optionally, in one alternative embodiment of the invention, due to the fact that in such a way... Figure 1In the cryogenic refrigeration device shown, the valve bodies of the solenoid valve (4) and the first one-way valve (10) impede the refrigerant, resulting in a lower refrigerant quantity and flow rate in the first microchannel heat exchanger (5) compared to the second microchannel heat exchanger (6) when both the first microchannel heat exchanger (5) and the second microchannel heat exchanger (6) are in operation. This leads to a decrease in the heat exchange area utilization rate of the first microchannel heat exchanger (5) due to uneven refrigerant distribution. Simultaneously, it increases the refrigerant pressure discharged from the microchannel heat exchanger at room temperature, thereby increasing the power consumption of the compressor (3) at room temperature. Therefore, this invention balances the refrigerant flow rate of the two microchannel heat exchangers by controlling the opening of the flow regulating valve (9) based on the pre-condensing temperature difference, thereby reducing the power consumption of the compressor (3) at room temperature.

[0065] Optionally, in another optional embodiment of the present invention, the aforementioned preset opening control table can be a data table set according to the refrigerant flow rate of the two microchannel heat exchangers at different condensing temperatures. This includes the condensing temperature difference and the corresponding target regulating valve opening value. The correspondence is as follows: Figure 3 As shown. When the current condensing temperature difference is less than ΔT1, the flow regulating valve (9) remains at 100% opening. ΔT1 is the minimum value of the preset temperature difference range, ΔT2 is the maximum value of the preset temperature difference range, the horizontal axis is the current condensing temperature difference value ΔT, and the vertical axis is the opening degree of the flow regulating valve (9).

[0066] Optionally, when the first pressure value is detected to be within the second preset pressure range, the following further steps are included:

[0067] Determine whether the first pressure value is consistent with the minimum value of the preset fan control range. If so, control the outdoor fan (16) to start running with the minimum speed in the preset fan speed table as the target speed.

[0068] When the first pressure value is greater than the minimum value of the preset fan control range, the speed corresponding to the first pressure value in the preset fan speed table is updated to the target speed, and the outdoor fan (16) is controlled to start running at the target speed.

[0069] Optionally, in one alternative embodiment of the present invention, the aforementioned preset fan speed table includes a correspondence between a first pressure value and the speed of the outdoor fan (16). The correspondence is as follows: Figure 4 As shown. Where x is the minimum speed of the outdoor fan (16), P1 is the minimum value of the preset fan control range, and P2 is the maximum value of the preset fan control range. The horizontal axis is the first pressure value, and the vertical axis is the percentage speed of the outdoor fan (16).

[0070] Optional, such as Figure 2 The control method shown also includes:

[0071] When the second pressure value collected by the low-pressure sensor (2) is not greater than the preset alarm pressure threshold, the compressor (3) is controlled to perform a shutdown protection action and an alarm message is sent to the preset monitoring system.

[0072] Optionally, when the first pressure value is less than the minimum value of the preset fan control range, the following further applies:

[0073] When the outdoor fan (16) is in operation and the first pressure value is detected to be less than the minimum value of the preset fan control range, the outdoor fan (16) is controlled to perform a preset delayed shutdown operation.

[0074] It should be noted that the rotational speed of the outdoor fan (16) affects the heat exchange efficiency of the microchannel heat exchanger, thus affecting the rate of change of the condensing pressure. Therefore, to avoid a sudden change in condensing pressure due to the immediate stop of the outdoor fan (16), which would result in an inaccurate first pressure value, the rate of change of the condensing pressure can be reduced by setting a delayed shutdown time for the outdoor fan (16), thereby improving the accuracy of the first pressure value.

[0075] This invention also provides a controller, such as... Figure 5 As shown, the controller includes:

[0076] Processor 501;

[0077] Memory 502 is used to store executable instructions of processor 501.

[0078] The processor 501 is configured to execute instructions to implement the control method of the cryogenic refrigeration device as described above.

[0079] This invention also provides a computer-readable storage medium that, when the instructions in the computer-readable storage medium are executed by the processor of a controller, enables the controller to perform a control method for a cryogenic refrigeration device as described above.

[0080] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, like read-only memory (ROM) or flash RAM, and memory includes at least one memory chip. Memory is an example of computer-readable media.

[0081] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0082] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0083] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0084] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0085] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A cryogenic refrigeration device, characterized in that, The cryogenic refrigeration device includes: Evaporator (1), low-pressure sensor (2), compressor (3), solenoid valve (4), first microchannel heat exchanger (5), second microchannel heat exchanger (6), first temperature sensor (7), second temperature sensor (8), flow regulating valve (9), first check valve (10), high-pressure sensor (11), second check valve (12), liquid storage tank (13), expansion valve (14), controller (15), and outdoor fan (16). The outlet of the evaporator (1) is connected to the inlet of the compressor (3). The outlet of the compressor (3) is connected to the inlet of the first microchannel heat exchanger (5) via the solenoid valve (4). The outlet of the first microchannel heat exchanger (5) is connected to the inlet of the first one-way valve (10). The outlet of the first one-way valve (10) is connected to the inlet of the second one-way valve (12). The outlet of the compressor (3) is connected to the inlet of the second microchannel heat exchanger (6). The outlet of the second microchannel heat exchanger (6) is connected to the inlet of the flow regulating valve (9). The outlet of the flow regulating valve (9) is connected to the inlet of the second one-way valve (12). The outlet of the second one-way valve (12) is connected to the inlet of the liquid storage tank (13). The outlet of the expansion valve (14) is connected to the inlet of the expansion valve (14), the outlet of the expansion valve (14) is connected to the inlet of the evaporator (1), the low pressure sensor (2) is located between the outlet of the evaporator (1) and the inlet of the compressor (3), the first microchannel heat exchanger (5) is equipped with the first temperature sensor (7), the second microchannel heat exchanger (6) is equipped with the second temperature sensor (8), the inlet of the second one-way valve (12) is equipped with the high pressure sensor (11), the low pressure sensor (2), the solenoid valve (4), the first temperature sensor (7), the second temperature sensor (8), the flow regulating valve (9), the high pressure sensor (11) and the outdoor fan (16) are all electrically connected to the controller (15); A control method for a cryogenic refrigeration device applied to the controller (15) in the aforementioned cryogenic refrigeration device includes: After the cryogenic refrigeration device is powered on and running, the first pressure value collected by the high-pressure sensor (11) at each operating moment is monitored, and a control strategy corresponding to the first pressure value is executed according to the magnitude of the first pressure value, wherein the control strategy includes: When the first pressure value is detected to be within the first preset pressure range, the solenoid valve (4) is controlled to be closed and the flow regulating valve (9) is controlled to be fully open, and the maximum value of the first preset pressure range is less than the first preset pressure threshold. When the first pressure value is detected to be within the second preset pressure range, the solenoid valve (4) is controlled to be in the open state, and the opening of the flow regulating valve (9) is adjusted according to the current condensing temperature difference value. The minimum value of the second preset pressure range is the second preset pressure threshold, the maximum value of the second preset pressure range is less than the third preset pressure threshold, the first preset pressure threshold is less than the second preset pressure threshold, and the current condensing temperature difference value is the difference between the temperatures collected by the first temperature sensor (7) and the second temperature sensor (8) at the current operating time.

2. The cryogenic refrigeration device according to claim 1, characterized in that, The solenoid valve (4) is a normally open solenoid valve.

3. The cryogenic refrigeration device according to claim 1, characterized in that, The low-temperature refrigeration device also includes an indoor fan.

4. A control method for a cryogenic refrigeration device, characterized in that, The control method is applied to the controller (15) in the cryogenic refrigeration device as described in any one of claims 1 to 3, and the control method includes: After the cryogenic refrigeration device is powered on and running, the first pressure value collected by the high-pressure sensor (11) at each operating moment is monitored, and a control strategy corresponding to the first pressure value is executed according to the magnitude of the first pressure value, wherein the control strategy includes: When the first pressure value is detected to be within the first preset pressure range, the solenoid valve (4) is controlled to be closed and the flow regulating valve (9) is controlled to be fully open, and the maximum value of the first preset pressure range is less than the first preset pressure threshold. When the first pressure value is detected to be within the second preset pressure range, the solenoid valve (4) is controlled to be in the open state, and the opening of the flow regulating valve (9) is adjusted according to the current condensing temperature difference value. The minimum value of the second preset pressure range is the second preset pressure threshold, the maximum value of the second preset pressure range is less than the third preset pressure threshold, the first preset pressure threshold is less than the second preset pressure threshold, and the current condensing temperature difference value is the difference between the temperatures collected by the first temperature sensor (7) and the second temperature sensor (8) at the current operating time.

5. The control method according to claim 4, characterized in that, The adjustment of the opening degree of the flow regulating valve (9) based on the current condensation temperature difference includes: Determine whether the current condensing temperature difference is within the preset temperature difference range. If so, find the opening value corresponding to the current condensing temperature difference in the preset opening control table and determine it as the target regulating valve opening value. Adjust the opening of the flow regulating valve (9) to the target regulating valve opening value. When the current condensation temperature difference is not less than the maximum value of the preset temperature difference range, the minimum opening value in the preset opening control table is updated to the target regulating valve opening value, and the opening of the flow regulating valve (9) is adjusted to the target regulating valve opening value.

6. The control method according to claim 4, characterized in that, When the first pressure value is detected to be within the second preset pressure range, the method further includes: Determine whether the first pressure value is consistent with the minimum value of the preset fan control range. If so, control the outdoor fan (16) to start running with the minimum speed in the preset fan speed table as the target speed. When the first pressure value is greater than the minimum value of the preset fan control range, the speed corresponding to the first pressure value in the preset fan speed table is updated to the target speed, and the outdoor fan (16) is controlled to start running at the target speed.

7. The control method according to claim 4, characterized in that, The method further includes: When the second pressure value collected by the low-pressure sensor (2) is not greater than the preset alarm pressure threshold, the compressor (3) is controlled to perform a shutdown protection action and an alarm message is sent to the preset monitoring system.

8. The control method according to claim 6, characterized in that, When the first pressure value is less than the minimum value of the preset fan control range, the method further includes: When the outdoor fan (16) is in operation and the first pressure value is detected to be less than the minimum value of the preset fan control range, the outdoor fan (16) is controlled to perform a preset delayed shutdown operation.

9. A controller, characterized in that, The controller includes: processor; Memory used to store the processor's executable instructions; The processor is configured to execute the instructions to implement the control method of the cryogenic refrigeration device as described in any one of claims 4 to 8.

10. A computer-readable storage medium, characterized in that, When the instructions in the computer-readable storage medium are executed by the processor of the controller, the controller is able to perform the control method of the cryogenic refrigeration apparatus as described in any one of claims 4 to 8.

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