Control method and device of refrigeration equipment, refrigeration equipment, storage medium and electronic equipment

Abstract

The invention provides a control method and device of refrigeration equipment, the refrigeration equipment, a storage medium and electronic device.The method comprises the steps that after a compressor of the refrigeration equipment is started, a liquid spraying branch and a refrigerant main path of the compressor are started, and the air suction end of the compressor is connected with the refrigerant main path and the liquid spraying branch at the same time; the other end of the liquid spraying branch path is connected to an outlet of the condenser, the other end of the refrigerant main path is connected to an outlet of the evaporator, and the refrigeration equipment comprises a compressor, the evaporator and the condenser; after the liquid spraying branch path and the refrigerant main path are opened, the starting duration of a compressor is monitored; and controlling the suction pressure and / or suction superheat degree of the compressor according to the starting duration. By adopting the scheme of the embodiment, the technical problem of instability caused by overlarge compression ratio after the compressor is started in the prior art is solved, the situation that the low starting pressure of the compressor is too low due to overhigh suction superheat degree is avoided, and the reliability of the compressor is improved.

Description

Technical Field

[0001] This invention relates to the field of refrigeration technology, and more specifically, to a control method and apparatus for refrigeration equipment, refrigeration equipment, storage medium, and electronic equipment. Background Technology

[0002] In related technologies, with the development of the times, the demand for cold storage is increasing. However, due to the large difference between ambient temperature and storage temperature, the outer ring is higher and the inner ring is lower. The compressor generally has a high pressure ratio, resulting in high exhaust temperature. Moreover, the refrigeration and freezing industry still uses a large number of fixed-frequency compressors, and the reliability of unit start-up is generally very poor, especially under high ambient temperature conditions.

[0003] In related technologies, cold storage facilities generally suffer from problems such as high outer ring temperature, low cold storage temperature, high pressure ratio, and high exhaust temperature. However, the solutions either tend to result in excessively low compression pressure or have a weak effect on reducing exhaust temperature.

[0004] No efficient and accurate solution has yet been found to address the aforementioned issues in the relevant technologies. Summary of the Invention

[0005] This invention provides a control method and device for refrigeration equipment, refrigeration equipment, storage medium, and electronic equipment to solve the technical problem of instability caused by excessive compression ratio after compressor startup in related technologies.

[0006] According to an embodiment of the present invention, a control method for a refrigeration device is provided, comprising: After the compressor of the refrigeration equipment is started, the liquid injection branch and the refrigerant main line of the compressor are opened. The suction end of the compressor is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. After the liquid injection branch and refrigerant main circuit are opened, monitor the start-up time of the compressor; The compressor's suction pressure and / or suction superheat are controlled according to the startup duration.

[0007] Optionally, activating the liquid injection branch of the compressor includes: The first real-time exhaust temperature of the compressor is collected, and the exhaust temperature protection threshold of the compressor is read. Calculate the first temperature difference between the first real-time exhaust temperature and the exhaust temperature protection threshold; Determine whether the first temperature difference is greater than or equal to the first threshold. If the first temperature difference is greater than or equal to the first threshold, the liquid injection branch of the compressor is opened to the preset opening degree.

[0008] Optionally, before monitoring the start-up duration of the compressor, the method further includes: The second real-time exhaust temperature of the compressor is collected, and the exhaust temperature protection threshold of the compressor is read. Calculate the second temperature difference between the second real-time exhaust temperature and the second exhaust temperature protection threshold; Determine whether the second temperature difference is greater than the second threshold. If the second temperature difference is greater than the second threshold, the spraying branch is kept in the open state; if the second temperature difference is less than or equal to the second threshold, the spraying branch is closed.

[0009] Optionally, controlling the compressor's suction pressure and / or suction superheat based on the startup duration includes: Determine the operational phase to which the startup duration belongs, wherein the operational phase includes a startup phase and a stable phase; Find the suction superheat range and suction pressure range that match the operating stage from the compressor's safety operating parameters; The compressor is controlled to operate within the range of suction superheat and the range of suction pressure.

[0010] Optionally, controlling the compressor to operate within the suction superheat range and the suction pressure range includes: The real-time suction temperature and real-time suction pressure of the compressor are collected; The real-time suction pressure is converted into a real-time evaporation temperature, and the real-time suction superheat of the compressor is calculated based on the real-time suction temperature and the real-time evaporation temperature. The opening degree of the liquid injection branch and the refrigerant main branch is controlled according to the real-time suction superheat and the real-time suction pressure, so that the compressor operates within the suction superheat range and the suction pressure range.

[0011] Optionally, controlling the opening degree of the liquid injection branch and the refrigerant main branch based on the real-time suction superheat and the real-time suction pressure includes: If the operation phase is the startup phase, determine whether the real-time inhalation superheat is less than the first superheat threshold and whether the real-time inhalation pressure is less than the first low pressure threshold. If the real-time intake superheat is less than the first superheat threshold, the opening of the liquid injection branch is increased by a preset step size; if the real-time intake pressure is less than the first low pressure threshold, the opening of the liquid injection branch is decreased by a preset step size, and the opening of the refrigerant main circuit is increased by a preset step size.

[0012] Optionally, controlling the opening degree of the liquid injection branch and the refrigerant main branch based on the real-time suction superheat and the real-time suction pressure includes: If the operation phase is a stable phase, determine whether the real-time inhalation superheat is within the safe range of superheat, and determine whether the real-time inhalation pressure is less than the first low pressure threshold. If the real-time suction superheat is not within the safe range of superheat, the opening of the refrigerant main circuit is controlled by PID; if the real-time suction pressure is less than the first low pressure threshold, the opening of the liquid injection branch circuit is reduced by a preset step size, and the opening of the refrigerant main circuit is increased by a preset step size.

[0013] Optionally, using PID control to control the opening degree of the refrigerant main circuit includes: The following PID formula is used to calculate the change in opening. : ,in, For PID coefficients, The difference between the real-time intake superheat and the target intake superheat during the current control cycle. This is the difference between the real-time inhalation superheat of the previous historical control cycle and the target inhalation superheat. The difference between the real-time inhalation superheat and the target inhalation superheat during the second preceding historical control cycle; The opening degree of the refrigerant main circuit is controlled by the change in opening degree.

[0014] According to another embodiment of the present invention, a control device for a refrigeration equipment is provided, comprising: The starting module is used to open the liquid injection branch and the refrigerant main line of the compressor after the compressor of the refrigeration equipment is started. The suction end of the compressor is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. The monitoring module is used to monitor the start-up time of the compressor after the liquid injection branch and the refrigerant main circuit are turned on; The control module is used to control the suction pressure and / or suction superheat of the compressor according to the startup duration.

[0015] Optionally, the activation module includes: The acquisition unit is used to acquire the first real-time exhaust temperature of the compressor and read the exhaust temperature protection threshold of the compressor. The acquisition unit is used to calculate the first temperature difference between the first real-time exhaust temperature and the exhaust temperature protection threshold. A judgment unit is used to determine whether the first temperature difference is greater than or equal to a first threshold. The activation unit is used to activate the liquid injection branch of the compressor to a preset opening degree if the first temperature difference is greater than or equal to a first threshold.

[0016] Optionally, the device further includes: The acquisition module is used to acquire the second real-time exhaust temperature of the compressor and read the exhaust temperature protection threshold of the compressor before the monitoring module monitors the start-up time of the compressor. The calculation module is used to calculate the second temperature difference between the second real-time exhaust temperature and the exhaust temperature protection threshold. The judgment module is used to determine whether the second temperature difference is greater than the second threshold. The determination module is used to maintain the spraying branch in the open state if the second temperature difference is greater than the second threshold; and to close the spraying branch if the second temperature difference is less than or equal to the second threshold.

[0017] Optionally, the control module includes: A determining unit is used to determine the operating phase to which the startup duration belongs, wherein the operating phase includes a startup phase and a stable phase; The lookup unit is used to find the suction superheat range and suction pressure range that match the operating stage in the safety operating condition parameters of the compressor. The control unit is used to control the compressor to operate within the suction superheat range and the suction pressure range.

[0018] Optionally, the control unit includes: The data acquisition unit is used to acquire the real-time suction temperature and real-time suction pressure of the compressor. The calculation unit is used to convert the real-time suction pressure into a real-time evaporation temperature, and to calculate the real-time suction superheat of the compressor based on the real-time suction temperature and the real-time evaporation temperature. The control unit is used to control the opening degree of the liquid injection branch and the refrigerant main branch according to the real-time suction superheat and the real-time suction pressure, so that the compressor operates within the suction superheat range and the suction pressure range.

[0019] Optionally, the control unit includes: The first judgment subunit is used to determine whether the real-time inhalation superheat is less than a first superheat threshold and whether the real-time inhalation pressure is less than a first low pressure threshold if the operation phase is the start-up phase. The first control subunit is configured to, if the real-time suction superheat is less than a first superheat threshold, increase the opening of the liquid injection branch by a preset step size; if the real-time suction pressure is less than a first low pressure threshold, decrease the opening of the liquid injection branch by a preset step size, and increase the opening of the refrigerant main circuit by a preset step size.

[0020] Optionally, the control unit includes: The second judgment subunit is used to determine whether the real-time inhalation superheat is within the safe range of superheat if the operation phase is a stable phase, and to determine whether the real-time inhalation pressure is less than the first low pressure threshold. The second control subunit is used to control the opening of the refrigerant main circuit using PID if the real-time suction superheat is not within the superheat safety range; and to reduce the opening of the liquid injection branch circuit by a preset step size and increase the opening of the refrigerant main circuit by a preset step size if the real-time suction pressure is less than the first low pressure threshold.

[0021] Optionally, the second control subunit is further configured to: The following PID formula is used to calculate the change in opening. : ,in, For PID coefficients, The difference between the real-time intake superheat and the target intake superheat during the current control cycle. This is the difference between the real-time inhalation superheat of the previous historical control cycle and the target inhalation superheat. The difference between the real-time inhalation superheat and the target inhalation superheat during the second preceding historical control cycle; The opening degree of the refrigerant main circuit is controlled by the change in opening degree.

[0022] According to another embodiment of the present invention, a refrigeration device is provided, comprising: a refrigeration device, characterized in that it includes a controller, a compressor, the evaporator, and a condenser, wherein the suction end of the compressor is simultaneously connected to a refrigerant main line and a liquid injection branch line, the other end of the liquid injection branch line is connected to the outlet of the condenser, the other end of the refrigerant main line is connected to the outlet of the evaporator, and the controller includes the control device of the refrigeration device described in the above embodiment.

[0023] According to another aspect of the embodiments of this application, a storage medium is also provided, the storage medium including a stored program that executes the above steps when the program is run.

[0024] According to another aspect of the embodiments of this application, an electronic device is also provided, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus; wherein: the memory is used to store computer programs; and the processor is used to execute the steps in the above method by running the programs stored in the memory.

[0025] According to yet another embodiment of the present invention, a storage medium is also provided, wherein a computer program is stored therein, wherein the computer program is configured to execute the steps in any of the above-described apparatus embodiments when running.

[0026] In this embodiment of the invention, after the compressor of the refrigeration equipment starts, the liquid injection branch and the main refrigerant line of the compressor are opened. The compressor's suction end is simultaneously connected to both the main refrigerant line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the main refrigerant line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. After opening the liquid injection branch and the main refrigerant line, the start-up time of the compressor is monitored. The suction pressure and / or suction superheat of the compressor are controlled based on the start-up time. This solves the technical problem in related technologies where the compression ratio is too high after compressor start-up, leading to instability. It also avoids excessively high suction superheat, which could result in excessively low compressor start-up pressure, thus improving the reliability of the compressor. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a hardware structure block diagram of a refrigeration device according to an embodiment of the present invention; Figure 2 This is a flowchart of a control method for a refrigeration device according to an embodiment of the present invention; Figure 3 This is a piping diagram of the refrigeration equipment in an embodiment of the present invention; Figure 4 This is a complete flowchart of an embodiment of the present invention; Figure 5 This is a structural block diagram of a control device for a refrigeration equipment according to an embodiment of the present invention. Detailed Implementation

[0028] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present application can be combined with each other.

[0029] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0030] Example 1 The method embodiment provided in Embodiment 1 of this application can be executed in control devices such as refrigerators, freezers, refrigeration equipment, cold storage, and controllers. Taking operation on refrigeration equipment as an example, Figure 1 This is a hardware structure block diagram of a refrigeration device according to an embodiment of the present invention. Figure 1 As shown, the refrigeration equipment may include one or more ( Figure 1 Only one is shown in the image. A processor 102 (which may include, but is not limited to, a microprocessor MCU or a programmable logic device FPGA, etc.) and a memory 104 for storing data are also shown. Optionally, the cooling device may further include a transmission device 106 for communication functions and an input / output device 108. Those skilled in the art will understand that... Figure 1 The structure shown is for illustrative purposes only and does not limit the structure of the refrigeration equipment described above. For example, the refrigeration equipment may also include... Figure 1 The more or fewer components shown, or having the same Figure 1 The different configurations shown.

[0031] The memory 104 can be used to store refrigeration equipment programs, such as application software programs and modules, like the refrigeration equipment program corresponding to a refrigeration equipment control method in this embodiment of the invention. The processor 102 executes various functional applications and data processing by running the refrigeration equipment program stored in the memory 104, thereby implementing the aforementioned method. The memory 104 may include high-speed random access memory and may also include non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some instances, the memory 104 may further include memory remotely located relative to the processor 102, and these remote memories can be connected to the refrigeration equipment via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0032] The transmission device 106 is used to receive or send data via a network. Specific examples of the network described above may include a wireless network provided by the communication provider of the cooling equipment. In one example, the transmission device 106 includes a Network Interface Controller (NIC), which can connect to other network devices via a base station to communicate with the Internet. In another example, the transmission device 106 may be a Radio Frequency (RF) module used for wireless communication with the Internet.

[0033] This embodiment provides a control method for a refrigeration device. Figure 2 This is a flowchart of a control method for a refrigeration device according to an embodiment of the present invention, such as... Figure 2 As shown, the process includes the following steps: Step S202: After the compressor of the refrigeration equipment is started, the liquid injection branch and the refrigerant main line of the compressor are opened. The suction end of the compressor is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. The refrigeration equipment in this embodiment can be a refrigerator, air conditioner, cold storage, etc., equipped with a compressor.

[0034] Figure 3This is a piping diagram of a refrigeration device in an embodiment of the present invention, including a compressor 1, a condenser 2, a liquid injection solenoid valve 3, a liquid injection electronic expansion valve 4, a pressure sensor 5, a temperature sensor 6, an evaporator 7, a suction temperature sensor 8, a suction pressure sensor 9, a discharge temperature sensor 10, a discharge temperature sensor 11, and an electronic expansion valve 12. The liquid injection solenoid valve 3, the liquid injection electronic expansion valve 4, the pressure sensor 5, and the temperature sensor 6 are located on the liquid injection branch line, and the refrigerant at the suction end of the compressor 1 is diverted to the main refrigerant path through the liquid injection branch line.

[0035] Step S204: After opening the liquid injection branch and the refrigerant main circuit, monitor the start-up time of the compressor; In this embodiment, after the compressor starts, it first goes through an unstable start-up phase and then enters a stable phase as the start-up time increases. The requirements for suction superheat are different in different phases. For example, the suction superheat (SH) maintenance range is: SH ≥ 1℃ in the initial start-up period, and SH = 5℃ ± 1℃ in the stable period; the suction pressure (low pressure) phased requirements are: Ps > ps1 (370 adjustable) kPa within 0-180 seconds of start-up, and Ps > ps1 (370 adjustable) kPa after 180 seconds.

[0036] Step S206: Control the suction pressure and / or suction superheat of the compressor according to the start-up duration.

[0037] Through the above steps, after the compressor of the refrigeration equipment starts, the liquid injection branch and the main refrigerant line of the compressor are opened. The compressor's suction end is simultaneously connected to both the main refrigerant line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the main refrigerant line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. After opening the liquid injection branch and the main refrigerant line, the compressor's start-up time is monitored. Based on the start-up time, the compressor's suction pressure and / or suction superheat are controlled. The discharge temperature is reduced through the liquid injection branch, and the compressor's suction pressure and / or suction superheat are controlled based on the start-up time. This solves the technical problem of instability caused by excessively high compression ratios after compressor start-up in related technologies, avoids excessively high suction superheat leading to excessively low compressor start-up pressure, and improves compressor reliability.

[0038] In one embodiment of this example, activating the liquid injection branch and refrigerant main circuit of the compressor includes: acquiring the first real-time discharge temperature of the compressor, the outer ring temperature and the inner ring temperature of the refrigeration equipment, and reading the discharge temperature protection threshold of the compressor; calculating the first temperature difference between the first real-time discharge temperature and the discharge temperature protection threshold, and calculating the second temperature difference between the outer ring temperature and the inner ring temperature; determining whether the first temperature difference is greater than or equal to the first threshold; if the first temperature difference is greater than or equal to the first threshold, activating the liquid injection branch of the compressor to a preset opening degree, and configuring the initial opening degree of the refrigerant main circuit according to the second temperature difference.

[0039] The system deploys sensors at key nodes: a temperature sensor and a pressure sensor are installed at the end of the compressor suction pipe to monitor the suction temperature Ts and suction pressure Ps in real time, and the suction pressure Ps is converted into the evaporation temperature Ts_(Ps); a temperature sensor and a pressure sensor are installed at the inlet of the exhaust pipe to detect the exhaust temperature Td and exhaust pressure Pd; and temperature / pressure sensors are configured in the liquid injection pipeline to monitor the liquid injection status.

[0040] Optionally, the compressor's preset operating parameters include the exhaust temperature protection threshold Tp, the injection circuit breaker start temperature Tsw, the start temperature for triggering the injection circuit breaker Tsw = Tp – 10 (configurable) °C, where –10 °C is the first threshold, and the temperature Tre for triggering the injection circuit breaker to close = Tp – 20 (configurable) °C, where –20 °C is the second threshold. Simultaneously, the compressor's first real-time exhaust temperature is collected. A first temperature difference is calculated between the first real-time exhaust temperature and the exhaust temperature protection threshold: First temperature difference = First real-time exhaust temperature - Exhaust temperature protection threshold. When the first temperature difference is greater than or equal to the first threshold, the injection circuit breaker is opened, with an initial opening fixed at 80%. Otherwise, the injection circuit breaker remains closed. The initial opening degree of the main EEV is determined based on the inner and outer loops, and will not be elaborated here.

[0041] The solution in this embodiment opens the liquid injection branch based on the first temperature difference between the real-time exhaust temperature and the exhaust temperature protection threshold, so that the compressor can reduce the exhaust temperature through the liquid injection branch when starting up, thereby reducing the pressure at the compressor's exhaust end and suction end and improving reliability.

[0042] In one implementation scenario of this embodiment, before monitoring the start-up time of the compressor, the method further includes: acquiring the second real-time exhaust temperature of the compressor and reading the exhaust temperature protection threshold of the compressor; calculating the second temperature difference between the second real-time exhaust temperature and the exhaust temperature protection threshold; determining whether the second temperature difference is greater than the second threshold; if the second temperature difference is greater than the second threshold, maintaining the liquid injection branch in the open state; if the second temperature difference is less than or equal to the second threshold, closing the liquid injection branch.

[0043] The temperature Tre that triggers the liquid injection shunt switch to close is Tp - 20 (settable) °C, where -20 °C is used as the second threshold. If the second threshold is less than the first threshold, the second temperature difference between the second real-time exhaust temperature and the exhaust temperature protection threshold is calculated. The second temperature difference is equal to the second real-time exhaust temperature minus the exhaust temperature protection threshold. If the second temperature difference is greater than the second threshold, it indicates that the real-time exhaust temperature is still relatively high, and the liquid injection shunt needs to be maintained. If the second temperature difference is less than or equal to the second threshold, it indicates that the compressor's exhaust temperature is low and the pressure ratio is small. In this case, the liquid injection shunt can be closed to allow the refrigerant to flow back to the main refrigerant circuit as much as possible, thereby improving the compressor's cooling effect.

[0044] In this embodiment, after the liquid injection branch is opened, the second temperature difference between the second real-time exhaust temperature and the exhaust temperature protection threshold is calculated. If the second temperature difference is greater than the second threshold, the liquid injection branch is kept open; otherwise, the liquid injection branch is closed. This ensures the reliability of the compressor while improving its cooling effect.

[0045] In one embodiment of this example, controlling the compressor's suction pressure and / or suction superheat based on the startup duration includes: determining the operating phase to which the startup duration belongs, wherein the operating phase includes a startup phase and a stabilization phase; searching for a suction superheat range and a suction pressure range that match the operating phase in the compressor's safety operating parameters; and controlling the compressor to operate within the suction superheat range and the suction pressure range.

[0046] Optionally, the start-up phase lasts from 0 to 180 seconds, and the stabilization phase lasts from 180 seconds after start-up. Different stages of the compressor correspond to different suction superheat and suction pressure ranges. For example, during the start-up phase: suction superheat (SH) ≥ 1℃, suction pressure Ps > ps1 (adjustable to 370) kPa; during the stabilization phase: SH = 5℃ ± 1℃, Ps > ps1 (adjustable to 370) kPa. The compressor is controlled to operate within this target state.

[0047] By using the solution in this embodiment, the compressor can be flexibly controlled according to the start-up time by matching the corresponding suction superheat range and suction pressure range, and by controlling the compressor to operate within the corresponding suction superheat range and suction pressure range. This ensures normal start-up of the compressor while improving the reliability of the compressor at different operating stages.

[0048] In one example, controlling the compressor to operate within the suction superheat range and the suction pressure range includes: collecting the real-time suction temperature and the real-time suction pressure of the compressor; converting the real-time suction pressure into a real-time evaporation temperature, and calculating the real-time suction superheat of the compressor according to the real-time suction temperature and the real-time evaporation temperature; controlling the opening degrees of the liquid injection branch and the refrigerant main path according to the real-time suction superheat and the real-time suction pressure, so that the compressor operates within the suction superheat range and the suction pressure range.

[0049] Among them, the suction pressure is Ps, the evaporation temperature is Ts_(Ps), the suction pressure Ps is converted into the evaporation temperature Ts_(Ps), and the suction superheat SH = Ts - Ts_(Ps).

[0050] Adopting the solution of this embodiment, based on the real-time suction temperature and the real-time suction pressure, and then obtaining the real-time suction superheat and the real-time suction pressure, the actual states of the suction superheat and the suction pressure can be obtained through the sensor data of the compressor, and then the compressor can be feedback-controlled, improving the control efficiency of the compressor.

[0051] In the scenario example of the compressor startup stage, controlling the opening degrees of the liquid injection branch and the refrigerant main path according to the real-time suction superheat and the real-time suction pressure includes: if the operation stage is the startup stage, judging whether the real-time suction superheat is less than the first superheat threshold, and judging whether the real-time suction pressure is less than the first low-pressure threshold; if the real-time suction superheat is less than the first superheat threshold, increasing the opening degree of the liquid injection branch by a preset step; if the real-time suction pressure is less than the first low-pressure threshold, reducing the opening degree of the liquid injection branch by a preset step, and increasing the opening degree of the refrigerant main path by a preset step.

[0052] In this scenario example, it is preferred to ensure that SH ≥ 1°C. If SH < 1°C, increase the opening degree of the liquid injection branch EEV (to 80% + Δ, the preset step Δ is an adaptive increment); if SH > 5°C, reduce the opening degree of the liquid injection branch EEV (to 80% - Δ). At the same time, ensure that Td < Tp (exhaust temperature protection threshold) Trigger of the liquid injection branch switch logic: When Td ≥ Tsw, the system enters the dynamic response mode, and the opening degrees of the liquid injection branch and the refrigerant main path can be adjusted. If it is simultaneously detected that Ps < 370 kPa (risk of too low low pressure), immediately perform the following operations: reduce the liquid injection branch EEV by 15%: reduce the liquid injection temperature to reduce the system heat load; increase the opening degree of the main path EEV by 10% to enhance the main refrigerant flow rate to increase the suction pressure.

[0053] Example: When Td = 116℃ and Ps = 360kPa, the EEV opening of the injection branch changes from 80% to 65%, and the EEV of the main branch changes from 50% to 60%, causing Ps to quickly rise to 375kPa and Td to fall below 120℃. After running for 30 seconds, if Td is still greater than Tsw and Ps is less than ps1, the EEV opening of the injection branch changes from 65% to 50%, and the EEV of the main branch changes from 60% to 70%, and so on, until Td is less than Tsw or Ps is greater than ps1.

[0054] In this embodiment, the real-time suction superheat and the real-time suction pressure control the opening of the liquid injection branch and the refrigerant main circuit. The liquid injection temperature is adjusted by adjusting the opening of the liquid injection branch to regulate the system heat load, and the main refrigerant flow rate is adjusted by adjusting the opening of the refrigerant main circuit to regulate the suction pressure, thereby achieving the reliability of the compressor during the start-up phase.

[0055] In a scenario example during the compressor's stable operation phase, controlling the opening degree of the liquid injection branch and the refrigerant main circuit based on the real-time suction superheat and the real-time suction pressure includes: if the operation phase is a stable phase, determining whether the real-time suction superheat is within the safe superheat range and whether the real-time suction pressure is less than a first low-pressure threshold; if the real-time suction superheat is not within the safe superheat range, using PID control to open the refrigerant main circuit; if the real-time suction pressure is less than the first low-pressure threshold, decreasing the opening degree of the liquid injection branch by a preset step size and increasing the opening degree of the refrigerant main circuit by a preset step size.

[0056] In the scenario example during the stable phase (after 180 seconds), maintain SH = 5℃ ± 0.5℃ and Ps > 370kPa. If Td ≥ 115℃ and Ps < 370kPa, repeat the above EEV opening adjustment (eEV for the injection branch → 65%, EEV for the main branch → 60%). It is also necessary to maintain Td < 125℃ (if Td ≥ 125℃, the compressor will shut down).

[0057] The scheme of this embodiment uses the real-time suction superheat and the real-time suction pressure to control the opening of the liquid injection branch and the refrigerant main circuit. The liquid injection temperature is adjusted by adjusting the opening of the liquid injection branch to regulate the system heat load, and the main refrigerant flow rate is adjusted by adjusting the opening of the refrigerant main circuit to regulate the suction pressure, thereby achieving the reliability of the compressor in the stable phase.

[0058] Optionally, using PID control to adjust the opening degree of the refrigerant main circuit includes calculating the opening degree change using the following PID formula. : ,in, For PID coefficients, The difference between the real-time intake superheat and the target intake superheat during the current control cycle. This is the difference between the real-time inhalation superheat of the previous historical control cycle and the target inhalation superheat. The difference between the real-time suction superheat and the target suction superheat in the second historical control cycle is used to control the opening degree of the refrigerant main circuit.

[0059] The opening degree of the main road EEV is controlled by a segmented adaptive PID controller, where U is the opening degree, k is the current value, and k-1 is the previous detection value. This represents the difference between the current inhalation superheat and the target SH. Taking a target inhalation superheat of 5℃ as an example, the safe range for superheat is 5℃ ± 0.5℃. =Real-time SH-5.

[0060] Furthermore, during the initial startup phase (0-60 seconds, rapid response), the refrigerant main circuit opening can be calculated based on the PID formula, where the PID coefficients are Kp=2.0, Ki=0.4, and Kd=1.0; from 60-180 seconds (transition): Kp=1.5, Ki=0.3, and Kd=0.8. After the 180-second steady-state phase, the PID coefficients in the PID formula are Kp=1.0, Ki=0.2, and Kd=0.5. The control cycle is set to 100ms to ensure parameter fluctuation ranges of: SH ≤±0.5℃, Td ≤±2℃.

[0061] The solution in this embodiment can avoid refrigerant flow oscillation in the main refrigerant circuit, thereby improving the stability of the compressor and the entire refrigeration equipment.

[0062] Figure 4 This is a complete flowchart of an embodiment of the present invention. Addressing the compressor reliability issue during the startup of the refrigeration system, this embodiment innovatively integrates the liquid injection circuit breaker logic with a dual electronic expansion valve (EEV) collaborative control strategy to achieve precise dynamic adjustment of exhaust temperature, suction superheat, and low-pressure. Sensors are deployed at key nodes: a temperature sensor and pressure sensor are installed at the end of the compressor suction pipe to monitor the suction temperature Ts and suction pressure Ps in real time, with the suction pressure Ps converted to the evaporation temperature Ts_(Ps); a temperature sensor and pressure sensor are installed at the exhaust pipe inlet to detect the exhaust temperature Td and exhaust pressure Pd; and temperature / pressure sensors are configured in the liquid injection pipeline to monitor the liquid injection status. After the system starts refrigeration operation, judgments are made based on the parameters collected from each sensor. If Td ≥ the injection shunt switch start temperature Tsw = Tp – 10 (settable) ℃, the injection shunt is opened, and the injection shunt EEV opening is fixed at 80%. If Td ≤ the injection shunt switch stop temperature Tre = Tp – 20 (settable) ℃, the injection shunt is closed; otherwise, it remains open. The exhaust temperature protection threshold Tp is used. At the same time, the main road EEV opening is fixed according to the inner and outer rings.

[0063] Differential control is performed based on the startup duration of the compressor, and the control objectives for different stages are preset. The maintenance range of the suction superheat (SH) is as follows: SH ≥ 1°C at the initial startup stage, and SH = 5°C ± 1°C during the stable stage; the phased requirements for the low-pressure pressure are: Ps > ps1 (370 can be set) kPa within 0 - 180 seconds after startup, and Ps > ps1 (370 can be set) kPa after 180 seconds, and SH = Ts - Ts_(Ps).

[0064] Startup stage (0 - 180 seconds): Priority is given to ensuring SH ≥ 1°C and Td < Tp. If SH < 1°C, increase the opening of the liquid injection branch EEV (to 80% + Δ, where Δ is the adaptive increment); if SH > 5°C, decrease the opening of the liquid injection branch EEV (to 80% - Δ). The switching logic trigger of the liquid injection branch: When Td ≥ Tsw, the system enters the dynamic response mode. If it is simultaneously detected that Ps < 370 kPa (risk of too low low pressure), immediately perform the following operations: Reduce the liquid injection branch EEV by 15%: Lower the liquid injection temperature to reduce the system heat load; increase the opening of the main path EEV by 10% to enhance the main refrigerant flow rate to increase the suction pressure; Stable stage (after 180 seconds): Maintain SH = 5°C ± 0.5°C, Td < 125°C (when Td ≥ 125°C, the compressor shuts down), and Ps > 370 kPa. If Td ≥ 115°C and Ps < 370 kPa, repeat the above EEV opening adjustment (liquid injection branch EEV → 65%, main path EEV → 60%).

[0065] Adopting the solution of this embodiment, after the compressor starts up, the exhaust temperature and suction superheat are detected, and intelligent control is carried out using the electronic expansion valves of the liquid injection branch and the main path to ensure that the suction superheat is maintained within a certain range, ensure that the exhaust temperature is lower than the operating range of the compressor exhaust temperature, and the suction superheat should not be too high to avoid too low low pressure during compressor startup, thereby improving the reliability of the compressor.

[0066] Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiments can be implemented by means of software plus a necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disc), including several instructions for causing a terminal device (which can be a mobile phone, computer, refrigerator, or network device, etc.) to execute the methods described in various embodiments of the present invention.

[0067] Embodiment This embodiment also provides a control device for a refrigeration device and a refrigeration device, which is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. The term "module" as used below refers to a combination of software and hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also conceivable.

[0068] Figure 5 This is a structural block diagram of a control device for a refrigeration equipment according to an embodiment of the present invention, such as... Figure 5 As shown, it includes: The starting module 50 is used to open the liquid injection branch and the refrigerant main line of the compressor after the compressor of the refrigeration equipment is started. The compressor's suction end is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. The monitoring module 52 is used to monitor the start-up time of the compressor after the liquid injection branch and the refrigerant main circuit are turned on; The control module 54 is used to control the suction pressure and / or suction superheat of the compressor according to the startup duration.

[0069] Optionally, the activation module includes: The acquisition unit is used to acquire the first real-time exhaust temperature of the compressor and read the exhaust temperature protection threshold of the compressor. The acquisition unit is used to calculate the first temperature difference between the first real-time exhaust temperature and the exhaust temperature protection threshold. A judgment unit is used to determine whether the first temperature difference is greater than or equal to a first threshold. The activation unit is used to activate the liquid injection branch of the compressor to a preset opening degree if the first temperature difference is greater than or equal to a first threshold.

[0070] Optionally, the device further includes: The acquisition module is used to acquire the second real-time exhaust temperature of the compressor and read the exhaust temperature protection threshold of the compressor before the monitoring module monitors the start-up time of the compressor. The calculation module is used to calculate the second temperature difference between the second real-time exhaust temperature and the exhaust temperature protection threshold. The judgment module is used to determine whether the second temperature difference is greater than the second threshold. The determination module is used to maintain the spraying branch in the open state if the second temperature difference is greater than the second threshold; and to close the spraying branch if the second temperature difference is less than or equal to the second threshold.

[0071] Optionally, the control module includes: A determining unit is used to determine the operating phase to which the startup duration belongs, wherein the operating phase includes a startup phase and a stable phase; The lookup unit is used to find the suction superheat range and suction pressure range that match the operating stage in the safety operating condition parameters of the compressor. The control unit is used to control the compressor to operate within the suction superheat range and the suction pressure range.

[0072] Optionally, the control unit includes: The data acquisition unit is used to acquire the real-time suction temperature and real-time suction pressure of the compressor. The calculation unit is used to convert the real-time suction pressure into a real-time evaporation temperature, and to calculate the real-time suction superheat of the compressor based on the real-time suction temperature and the real-time evaporation temperature. The control unit is used to control the opening degree of the liquid injection branch and the refrigerant main branch according to the real-time suction superheat and the real-time suction pressure, so that the compressor operates within the suction superheat range and the suction pressure range.

[0073] Optionally, the control unit includes: The first judgment subunit is used to determine whether the real-time inhalation superheat is less than a first superheat threshold and whether the real-time inhalation pressure is less than a first low pressure threshold if the operation phase is the start-up phase. The first control subunit is configured to, if the real-time suction superheat is less than a first superheat threshold, increase the opening of the liquid injection branch by a preset step size; if the real-time suction pressure is less than a first low pressure threshold, decrease the opening of the liquid injection branch by a preset step size, and increase the opening of the refrigerant main circuit by a preset step size.

[0074] Optionally, the control unit includes: The second judgment subunit is used to determine whether the real-time inhalation superheat is within the safe range of superheat if the operation phase is a stable phase, and to determine whether the real-time inhalation pressure is less than the first low pressure threshold. The second control subunit is used to control the opening of the refrigerant main circuit using PID if the real-time suction superheat is not within the superheat safety range; and to reduce the opening of the liquid injection branch circuit by a preset step size and increase the opening of the refrigerant main circuit by a preset step size if the real-time suction pressure is less than the first low pressure threshold.

[0075] Optionally, the second control subunit is further configured to: The following PID formula is used to calculate the change in opening. : ,in, For PID coefficients, The difference between the real-time intake superheat and the target intake superheat during the current control cycle. This is the difference between the real-time inhalation superheat of the previous historical control cycle and the target inhalation superheat. This is the difference between the real-time inhalation superheat and the target inhalation superheat during the second-to-last historical control cycle. The opening degree of the refrigerant main circuit is controlled by the change in opening degree.

[0076] According to another embodiment of the present invention, a refrigeration device is provided, comprising: a refrigeration device, characterized in that it includes a controller, a compressor, the evaporator, and a condenser, wherein the suction end of the compressor is simultaneously connected to a refrigerant main line and a liquid injection branch line, the other end of the liquid injection branch line is connected to the outlet of the condenser, the other end of the refrigerant main line is connected to the outlet of the evaporator, and the controller includes the control device of the refrigeration device described in the above embodiment.

[0077] It should be noted that the above modules can be implemented by software or hardware. For the latter, they can be implemented in the following ways, but are not limited to: all the above modules are located in the same processor; or, the above modules are located in different processors in any combination.

[0078] Example 3 Embodiments of the present invention also provide a storage medium storing a computer program, wherein the computer program is configured to execute the steps in any of the above method embodiments when running.

[0079] Optionally, in this embodiment, the storage medium can be configured to store a computer program for execution: S1, after the compressor of the refrigeration equipment is started, the liquid injection branch and the refrigerant main line of the compressor are opened. The suction end of the compressor is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. S2, after opening the liquid injection branch and the refrigerant main circuit, monitor the start-up time of the compressor; S3, control the compressor's suction pressure and / or suction superheat according to the startup duration.

[0080] Optionally, in this embodiment, the storage medium may include, but is not limited to, various media capable of storing computer programs, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0081] Embodiments of the present invention also provide an electronic device including a memory and a processor, the memory storing a computer program and the processor being configured to run the computer program to perform the steps in any of the above method embodiments.

[0082] Optionally, the electronic device may further include a transmission device and an input / output device, wherein the transmission device is connected to the processor and the input / output device is connected to the processor.

[0083] Optionally, in this embodiment, the processor can be configured to perform the following steps via a computer program: S1, after the compressor of the refrigeration equipment is started, the liquid injection branch and the refrigerant main line of the compressor are opened. The suction end of the compressor is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. S2, after opening the liquid injection branch and the refrigerant main circuit, monitor the start-up time of the compressor; S3, control the compressor's suction pressure and / or suction superheat according to the startup duration.

[0084] Optionally, specific examples in this embodiment can refer to the examples described in the above embodiments and optional implementations, and will not be repeated here.

[0085] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0086] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0087] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection of units or modules may be electrical or other forms.

[0088] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0089] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0090] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, controller, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard drive, magnetic disk, or optical disk.

[0091] The above are merely preferred embodiments of this application. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A control method for a refrigeration device, characterized in that, include: After the compressor of the refrigeration equipment is started, the liquid injection branch and the refrigerant main line of the compressor are opened. The suction end of the compressor is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. After the liquid injection branch and the refrigerant main circuit are opened, the start-up time of the compressor is monitored; The compressor's suction pressure and / or suction superheat are controlled according to the startup duration.

2. The method according to claim 1, characterized in that, Activating the liquid injection branch of the compressor includes: The first real-time exhaust temperature of the compressor is collected, and the exhaust temperature protection threshold of the compressor is read. Calculate the first temperature difference between the first real-time exhaust temperature and the exhaust temperature protection threshold; Determine whether the first temperature difference is greater than or equal to the first threshold. If the first temperature difference is greater than or equal to the first threshold, the liquid injection branch of the compressor is opened to the preset opening degree.

3. The method according to claim 1, characterized in that, Before monitoring the start-up duration of the compressor, the method further includes: The second real-time exhaust temperature of the compressor is collected, and the exhaust temperature protection threshold of the compressor is read. Calculate the second temperature difference between the second real-time exhaust temperature and the second exhaust temperature protection threshold; Determine whether the second temperature difference is greater than the second threshold. If the second temperature difference is greater than the second threshold, the spraying branch is kept in the open state; if the second temperature difference is less than or equal to the second threshold, the spraying branch is closed.

4. The method according to claim 1, characterized in that, Controlling the compressor's suction pressure and / or suction superheat based on the startup duration includes: Determine the operational phase to which the startup duration belongs, wherein the operational phase includes a startup phase and a stable phase; Find the suction superheat range and suction pressure range that match the operating stage from the compressor's safety operating parameters; The compressor is controlled to operate within the range of suction superheat and the range of suction pressure.

5. The method according to claim 4, characterized in that, Controlling the compressor to operate within the suction superheat range and the suction pressure range includes: The real-time suction temperature and real-time suction pressure of the compressor are collected; The real-time suction pressure is converted into a real-time evaporation temperature, and the real-time suction superheat of the compressor is calculated based on the real-time suction temperature and the real-time evaporation temperature. The opening degree of the liquid injection branch and the refrigerant main branch is controlled according to the real-time suction superheat and the real-time suction pressure, so that the compressor operates within the suction superheat range and the suction pressure range.

6. The method according to claim 5, characterized in that, Controlling the opening degree of the liquid injection branch and the refrigerant main circuit based on the real-time suction superheat and the real-time suction pressure includes: If the operation phase is the startup phase, determine whether the real-time inhalation superheat is less than the first superheat threshold and whether the real-time inhalation pressure is less than the first low pressure threshold. If the real-time intake superheat is less than the first superheat threshold, the opening of the liquid injection branch is increased by a preset step size; if the real-time intake pressure is less than the first low pressure threshold, the opening of the liquid injection branch is decreased by a preset step size, and the opening of the refrigerant main circuit is increased by a preset step size.

7. The method according to claim 5, characterized in that, Controlling the opening degree of the liquid injection branch and the refrigerant main circuit based on the real-time suction superheat and the real-time suction pressure includes: If the operation phase is a stable phase, determine whether the real-time inhalation superheat is within the safe range of superheat, and determine whether the real-time inhalation pressure is less than the first low pressure threshold. If the real-time suction superheat is not within the safe range of superheat, the opening of the refrigerant main circuit is controlled by PID; if the real-time suction pressure is less than the first low pressure threshold, the opening of the liquid injection branch circuit is reduced by a preset step size, and the opening of the refrigerant main circuit is increased by a preset step size.

8. The method according to claim 7, characterized in that, The PID control of the refrigerant main circuit opening includes: The following PID formula is used to calculate the change in opening. : ,in, For PID coefficients, This is the difference between the real-time intake superheat and the target intake superheat during the current control cycle. This is the difference between the real-time inhalation superheat of the previous historical control cycle and the target inhalation superheat. This is the difference between the real-time inhalation superheat and the target inhalation superheat during the second-to-last historical control cycle. The opening degree of the refrigerant main circuit is controlled by the change in opening degree.

9. A control device for a refrigeration equipment, characterized in that, include: The starting module is used to open the liquid injection branch and the refrigerant main line of the compressor after the compressor of the refrigeration equipment is started. The suction end of the compressor is connected to both the refrigerant main line and the liquid injection branch. The other end of the liquid injection branch is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The refrigeration equipment includes the compressor, the evaporator, and the condenser. The monitoring module is used to monitor the start-up time of the compressor after the liquid injection branch and the refrigerant main circuit are turned on; The control module is used to control the suction pressure and / or suction superheat of the compressor according to the startup duration.

10. A refrigeration device, characterized in that, The device includes a controller, a compressor, the evaporator, and a condenser. The compressor's suction end is connected to both a refrigerant main line and a liquid injection branch line. The other end of the liquid injection branch line is connected to the outlet of the condenser, and the other end of the refrigerant main line is connected to the outlet of the evaporator. The controller includes the control device for the refrigeration equipment as described in claim 9.

11. A storage medium, characterized in that, The storage medium stores a computer program, wherein the computer program is configured to execute the steps of the control method for the refrigeration device according to any one of claims 1 to 8 when it is run.

12. An electronic device comprising a processor, a communication interface, a memory, and a communication bus, wherein, The processor, communication interface, and memory communicate with each other via a communication bus; among which: Memory, used to store computer programs; A processor is configured to execute the steps of the control method for the refrigeration device according to any one of claims 1 to 8 by running a program stored in memory.

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