Single-stage refrigeration system and method for steplessly adjusting refrigeration capacity and dehumidification capacity

Abstract

The present invention relates to a single-stage refrigeration system and method for steplessly adjusting the refrigeration capacity and dehumidification capacity, and belongs to the field of control technology. The single-stage refrigeration system and method for steplessly adjusting the refrigeration capacity and dehumidification capacity of the invention, its refrigeration circuit and dehumidification circuit can respectively accurately control the refrigeration capacity and dehumidification capacity, so as not to adopt the antagonistic adjustment in the prior art, reduce the use frequency of the heating system and the humidification system, and reduce the operating cost of refrigeration and dehumidification; at the same time, through the stepless adjustment of the refrigeration capacity, the refrigeration capacity is only provided according to the needs, and the average temperature of the evaporator is slightly lower than the control temperature in the box, which reduces the possibility of frost on the evaporator. There is no frost problem at temperatures above 0°C, ensuring that the test box can operate at a stable temperature for a long time, and improving the reliability of the test box. The single-stage refrigeration system and method for steplessly adjusting the refrigeration capacity and dehumidification capacity of the present invention have a simple system structure, convenient maintenance, simple method application, and a very wide range of applications.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature and humidity control, and in particular to the technical field of control for refrigeration and dehumidification of a test chamber, and specifically refers to a single-stage refrigeration system and method for steplessly adjusting refrigeration capacity and dehumidification capacity. Background Art

[0002] Temperature and humidity test chambers require continuous and precise regulation of temperature and humidity inside the chamber. The air conditioning industry usually adopts

[0003] The current regulation method of starting and stopping the compressor cannot meet the control needs of the temperature and humidity test chamber. In addition, since the temperature adjustment span of the test chamber is large (-40℃ to +150℃), and extreme low and high temperatures need to be achieved, variable frequency compressors cannot be used in many working conditions.

[0004] At present, the mainstream refrigeration system of temperature and humidity test chamber adopts a simple refrigeration system, which can only maintain a constant temperature.

[0005] The cooling capacity or the cooling capacity and dehumidification capacity can be adjusted in sections by switching solenoid valves with different flow rates. The temperature and humidity control in the test chamber adopts a balanced temperature and humidity control method, that is, the temperature control adopts a variable heating capacity and a constant cooling capacity for counter-adjustment to achieve temperature balance; the humidity control in the test chamber adopts a variable humidification capacity and a constant cooling capacity for counter-adjustment to achieve humidity balance. Since the refrigeration system is always working, the average temperature of the evaporator is much lower than the control temperature in the chamber, and it is easy to frost at low temperature or even at normal temperature, affecting the refrigeration effect and the long-term stability of the test chamber.

[0006] Therefore, how to provide a method that can accurately control the cooling capacity and dehumidification capacity without using confrontation adjustment, reduce the use frequency of the heating system and the humidification system, reduce the operating cost of the refrigeration and dehumidification, and thus improve the test efficiency?

[0007] A refrigeration system and method for testing the reliability of a box has become a problem to be solved urgently in this field. Summary of the invention

[0008] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a stepless cooling capacity adjustment method.

[0009] Single-stage refrigeration system and method for cooling and dehumidification. The system and method can accurately control the cooling capacity and dehumidification capacity without using antagonistic adjustment, reduce the use frequency of the heating system and the humidification system, and reduce the operating cost of refrigeration and dehumidification. At the same time, through the stepless adjustment of the cooling capacity, the cooling capacity is only provided according to the needs. The average temperature of the evaporator is slightly lower than the control temperature in the box, which reduces the possibility of frost on the evaporator. There is no frost problem at temperatures above 0°C, ensuring that the test box can operate at a stable temperature for a long time and improving the reliability of the test box.

[0010] In order to achieve the above-mentioned purpose, the single-stage refrigeration system of the present invention which steplessly adjusts the refrigeration capacity and the dehumidification capacity has the following structure:

[0011] The single-stage refrigeration system for steplessly adjusting refrigeration capacity and dehumidification capacity comprises: a control subsystem, a compressor,

[0012] Refrigeration circuit and dehumidification circuit.

[0013] Among them, the control subsystem includes an ambient temperature and humidity acquisition device for calculating the cooling capacity and dehumidification capacity according to the ambient temperature and humidity and the target temperature and humidity; the compressor provides system circulation power through an adiabatic compression process; the refrigeration circuit includes a refrigeration evaporator connected to the compressor through a refrigeration solenoid valve, and the control subsystem controls the refrigeration solenoid valve according to the refrigeration capacity to achieve stepless adjustment of the refrigeration capacity; the dehumidification circuit includes a dehumidification evaporator connected to the compressor through a dehumidification solenoid valve, and the control subsystem controls the dehumidification solenoid valve according to the dehumidification capacity to achieve stepless adjustment of the dehumidification capacity.

[0014] In the single-stage refrigeration system with stepless adjustment of cooling capacity and dehumidification capacity, the control subsystem controls the refrigeration solenoid valve according to the refrigeration capacity specifically as follows: the control subsystem calculates and controls the opening time of the refrigeration solenoid valve within a unit cycle according to the refrigeration capacity and the temperature control cycle.

[0015] In the single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity, the refrigeration circuit also includes a refrigeration expansion valve arranged between the refrigeration solenoid valve and the refrigeration evaporator, and the refrigeration expansion valve is used to control the flow rate of the refrigeration circuit and the evaporation temperature of the refrigeration evaporator.

[0016] In the single-stage refrigeration system with stepless adjustment of cooling capacity and dehumidification capacity, the control subsystem controls the dehumidification solenoid valve according to the dehumidification capacity, specifically: the control subsystem calculates and controls the opening time of the dehumidification solenoid valve within a unit cycle according to the dehumidification capacity and the humidity control cycle.

[0017] In the single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity, the dehumidification circuit also includes a dehumidification top cover valve arranged between the dehumidification solenoid valve and the dehumidification evaporator, and the dehumidification top cover valve is used to control the flow of the dehumidification circuit.

[0018] The single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity also includes a hot gas bypass circuit, including a hot gas bypass solenoid valve connected to the compressor. When the refrigeration solenoid valve and the dehumidification solenoid valve are both closed, the control subsystem controls the hot gas bypass solenoid valve to open, and utilizes the hot gas bypass circuit to ensure the suction and exhaust of the compressor.

[0019] The single-stage refrigeration system with stepless adjustment of cooling capacity and dehumidification capacity also includes a liquid spray cooling circuit, including a liquid spray cooling solenoid valve connected to the compressor through the hot gas bypass circuit. When the hot gas bypass magnetic valve is opened, the control subsystem controls the liquid spray cooling solenoid valve to open, and utilizes the liquid spray cooling circuit to ensure the exhaust temperature of the compressor.

[0020] In the single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity, the control subsystem also includes a suction pressure sensor arranged on the compressor. When the suction pressure of the compressor is greater than a preset value, the refrigeration circuit, the dehumidification circuit and the hot gas bypass circuit are controlled to be closed.

[0021] The present invention also provides a single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity using the above system, the method comprising the following steps:

[0022] (A) The control subsystem calculates the cooling capacity and dehumidification capacity according to the ambient temperature and humidity and the target temperature and humidity;

[0023] (B) controlling a refrigeration solenoid valve connected between the compressor and the refrigeration evaporator in the refrigeration circuit according to the refrigeration capacity to achieve stepless regulation of the refrigeration capacity;

[0024] (C) According to the dehumidification amount, a dehumidification solenoid valve connected between the compressor and the dehumidification evaporator in the dehumidification circuit is controlled to achieve stepless regulation of the dehumidification amount.

[0025] In the single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity, the step (B) is specifically as follows:

[0026] The control subsystem calculates and controls the opening time of the refrigeration solenoid valve within a unit cycle according to the refrigeration capacity and the temperature control cycle.

[0027] In the single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity, the step (B) further comprises the following steps:

[0028] The control subsystem controls the refrigeration expansion valve connected between the refrigeration solenoid valve and the refrigeration evaporator to control the flow rate of the refrigeration circuit and the evaporation temperature of the refrigeration evaporator.

[0029] In the single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity, the step (C) is specifically as follows:

[0030] The control subsystem calculates and controls the opening time of the dehumidification solenoid valve within a unit cycle according to the dehumidification amount and the humidity control cycle.

[0031] In the single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity, the step (C) further comprises the following steps:

[0032] The control subsystem controls the dehumidification top cover valve connected between the dehumidification solenoid valve and the dehumidification evaporator to control the flow of the dehumidification circuit.

[0033] The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity also includes the following steps:

[0034] (D) When the refrigeration solenoid valve and the dehumidification solenoid valve are both closed, the control subsystem controls the hot gas bypass solenoid valve connected to the compressor in the hot gas bypass circuit to open, and utilizes the hot gas bypass circuit to ensure the suction and exhaust of the compressor.

[0035] The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity also includes the following steps:

[0036] (E) When the hot gas bypass solenoid valve is opened, the control subsystem controls the opening of the liquid spray cooling solenoid valve in the liquid spray cooling circuit connected to the compressor through the hot gas bypass circuit, and utilizes the liquid spray cooling circuit to ensure the exhaust temperature of the compressor.

[0037] The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity also includes the following steps:

[0038] (F) According to the value obtained from the suction pressure sensor provided in the compressor, when the suction pressure of the compressor is greater than a preset value, the control subsystem controls closing of the refrigeration circuit, the dehumidification circuit and the hot gas bypass circuit.

[0039] The single-stage refrigeration system and method for steplessly adjusting the refrigeration capacity and dehumidification capacity of the invention are adopted. The refrigeration circuit and dehumidification circuit can respectively accurately control the refrigeration capacity and dehumidification capacity, thereby eliminating the need for the antagonistic adjustment in the prior art, reducing the use frequency of the heating system and the humidification system, and reducing the operating cost of refrigeration and dehumidification; at the same time, through the stepless adjustment of the refrigeration capacity, the refrigeration capacity is only provided according to the needs, and the average temperature of the evaporator is slightly lower than the control temperature in the box, which reduces the possibility of frost on the evaporator. There is no frost problem at temperatures above 0°C, ensuring that the test box can operate at a stable temperature for a long time, and improving the reliability of the test box. The single-stage refrigeration system and method for steplessly adjusting the refrigeration capacity and dehumidification capacity of the present invention have a simple system structure, convenient maintenance, simple method application, and a very wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural schematic diagram of a single-stage refrigeration system for steplessly adjusting refrigeration capacity and dehumidification capacity of the present invention.

[0041] Figure 2 The present invention is a flow chart of the steps of a single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity. DETAILED DESCRIPTION

[0042] In order to more clearly understand the technical content of the present invention, the following embodiments are given in detail.

[0043] See also Figure 1 The figure is a schematic diagram of the structure of a single-stage refrigeration system for steplessly adjusting refrigeration capacity and dehumidification capacity according to the present invention.

[0044] In one embodiment, the single-stage refrigeration system for steplessly adjusting refrigeration capacity and dehumidification capacity comprises: a control subsystem, a compressor 1, a refrigeration circuit and a dehumidification circuit.

[0045] The control subsystem includes an ambient temperature and humidity acquisition device for calculating the cooling capacity and dehumidification capacity according to the ambient temperature and humidity and the target temperature and humidity; the compressor 1 provides system circulation power through an adiabatic compression process; the refrigeration circuit includes a refrigeration evaporator 23 connected to the compressor 1 through a refrigeration solenoid valve 20, and the control subsystem controls the refrigeration solenoid valve 20 according to the refrigeration capacity to achieve stepless regulation of the refrigeration capacity; the dehumidification circuit includes a dehumidification evaporator 27 connected to the compressor 1 through a dehumidification solenoid valve 24, and the control subsystem controls the dehumidification solenoid valve 24 according to the dehumidification capacity to achieve stepless regulation of the dehumidification capacity.

[0046] A single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity using the system described in the above embodiment is as follows: Figure 2 As shown, the following steps are included:

[0047] (A) The control subsystem calculates the cooling capacity and dehumidification capacity according to the ambient temperature and humidity and the target temperature and humidity;

[0048] (B) According to the cooling capacity, the refrigeration circuit connected to the compressor 1 and the refrigeration evaporator 23 is controlled

[0049] The refrigeration solenoid valve 20 between them realizes stepless regulation of refrigeration capacity;

[0050] (C) According to the dehumidification amount, the dehumidification solenoid valve 24 connected between the compressor 1 and the dehumidification evaporator 27 in the dehumidification circuit is controlled to achieve stepless regulation of the dehumidification amount.

[0051] In a preferred embodiment, the control subsystem controls the refrigeration solenoid valve 20 according to the refrigeration capacity, specifically: the control subsystem calculates and controls the opening time of the refrigeration solenoid valve 20 in a unit cycle according to the refrigeration capacity and the temperature control cycle. At the same time, the refrigeration circuit also includes a refrigeration expansion valve 21 arranged between the refrigeration solenoid valve 20 and the refrigeration evaporator 23, and the refrigeration expansion valve 21 is used to control the flow of the refrigeration circuit and the evaporation temperature of the refrigeration evaporator 23.

[0052] In the single-stage refrigeration method for steplessly adjusting the refrigeration capacity and the dehumidification capacity by using the system described in the above embodiment, the step (B) further includes the following steps:

[0053] The control subsystem calculates and controls the opening time of the refrigeration solenoid valve 20 within a unit cycle according to the refrigeration capacity and the temperature control cycle;

[0054] The control subsystem controls the refrigeration expansion valve 21 connected between the refrigeration solenoid valve 20 and the refrigeration evaporator 23 to control the flow rate of the refrigeration circuit and the evaporation temperature of the refrigeration evaporator 23 .

[0055] In a further preferred embodiment, the control subsystem controls the dehumidification solenoid valve 24 according to the dehumidification amount, specifically: the control subsystem calculates and controls the opening time of the dehumidification solenoid valve 24 in a unit cycle according to the dehumidification amount and the humidity control cycle. At the same time, the dehumidification circuit also includes a dehumidification top cover valve 25 arranged between the dehumidification solenoid valve 24 and the dehumidification evaporator 27, and the dehumidification top cover valve 25 is used to control the flow of the dehumidification circuit.

[0056] The single-stage refrigeration method for steplessly adjusting the refrigeration capacity and the dehumidification capacity by using the system described in the above embodiment is characterized in that the step (C) further comprises the following steps:

[0057] The control subsystem calculates and controls the opening time of the dehumidification solenoid valve 24 within a unit cycle according to the dehumidification amount and the humidity control cycle;

[0058] The control subsystem controls the dehumidification top cover valve 25 connected between the dehumidification solenoid valve 24 and the dehumidification evaporator 27 to control the flow of the dehumidification circuit.

[0059] In a further preferred embodiment, the single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity further includes a hot gas bypass circuit and a liquid spray cooling circuit.

[0060] The hot gas bypass circuit includes a hot gas bypass solenoid valve 13 connected to the compressor 1. When the refrigeration solenoid valve 20 and the dehumidification solenoid valve 24 are both closed, the control subsystem controls the hot gas bypass solenoid valve 13 to open, and utilizes the hot gas bypass circuit to ensure the suction and exhaust of the compressor 1.

[0061] The liquid spray cooling circuit includes a liquid spray cooling solenoid valve 18 connected to the compressor 1 through the hot gas bypass circuit. When the hot gas bypass solenoid valve 13 is opened, the control subsystem controls the liquid spray cooling solenoid valve 18 to open, and utilizes the liquid spray cooling circuit to ensure the exhaust temperature of the compressor 1.

[0062] The single-stage refrigeration method for steplessly adjusting the refrigeration capacity and the dehumidification capacity using the system described in the above embodiment further includes the following steps:

[0063] When the refrigeration solenoid valve 20 and the dehumidification solenoid valve 24 are both closed, the control subsystem controls the hot gas bypass solenoid valve 13 connected to the compressor 1 in the hot gas bypass circuit to open, and the hot gas bypass circuit is used to ensure the suction and exhaust of the compressor 1.

[0064] (E) When the hot gas bypass solenoid valve 13 is opened, the control subsystem controls the opening of the liquid spray cooling solenoid valve 18 in the liquid spray cooling circuit connected to the compressor 1 through the hot gas bypass circuit, and utilizes the liquid spray cooling circuit to ensure the exhaust temperature of the compressor 1.

[0065] In a more preferred embodiment, the control subsystem also includes a suction pressure sensor 5 arranged on the compressor 1. When the suction pressure of the compressor 1 is greater than a preset value, the refrigeration circuit, the dehumidification circuit and the hot gas bypass circuit are controlled to be closed.

[0066] The single-stage refrigeration method for steplessly adjusting the refrigeration capacity and the dehumidification capacity using the system described in the above embodiment further includes the following steps:

[0067] (F) According to the value obtained from the suction pressure sensor 5 arranged on the compressor 1, when the suction pressure of the compressor 1 is greater than a preset value, the control subsystem controls the closure of the refrigeration circuit, the dehumidification circuit and the hot gas bypass circuit.

[0068] In practical applications, the single-stage refrigeration method of the present invention for steplessly adjusting the refrigeration capacity and the dehumidification capacity can be divided into control methods for the following components:

[0069] 1. Refrigeration circuit control: The cooling capacity calculated by the control system PID is multiplied by the temperature control cycle (e.g., the default control cycle is 10 seconds, and the control cycle can be set by the control system) to determine the opening time of the refrigeration solenoid valve 20 in each control cycle. For example, if the refrigeration output is 15%, the opening time of the refrigeration solenoid valve 20 in a control cycle is 1.5 seconds, and the closing time is 8.5 seconds. The refrigeration expansion valve 21 is adjusted according to the required limit temperature to maintain the lowest temperature, and when the forced refrigeration output is 100%, the outlet of the refrigeration evaporator 23 has a superheat of +5°C.

[0070] The refrigeration circuit may further include a refrigeration distributor 22 connected between the refrigeration expansion valve 21 and the refrigeration evaporator 23 , and the refrigeration distributor 22 is used to evenly distribute the flow of each circuit of the refrigeration evaporator 23 .

[0071] 2. Dehumidification circuit control: The dehumidification amount calculated by the control system PID is multiplied by the humidity control cycle (the default is 10 seconds, and the control cycle can be set by the control system) to determine the opening time of the dehumidification solenoid valve 24 in each control cycle. For example: if the dehumidification output is 15%, the opening time of the dehumidification solenoid valve 24 in a control cycle is 1.5 seconds, and the closing time is 8.5 seconds. The adjustment of the dehumidification top cover valve 25 ensures that the temperature and humidity in the control box are +23°C, 50%RH, and the forced dehumidification output is 100%. When the refrigeration solenoid valve 20 is closed, the suction pressure sensor 5 indicates greater than 0.3bar, and the outlet of the dehumidification evaporator 27 is greater than 0°C, so that the dehumidification evaporator 27 can achieve a good dehumidification effect under various working conditions and will not frost.

[0072] The dehumidification circuit may further include a dehumidification distributor 26 connected between the dehumidification top cover valve 25 and the dehumidification evaporator 27 , and the dehumidification distributor 26 is used to evenly distribute the flow of each circuit of the dehumidification evaporator 27 .

[0073] 3. Hot gas bypass circuit control: When the refrigeration solenoid valve 20 and the dehumidification solenoid valve 24 are closed, the hot gas bypass solenoid valve 13 is opened to ensure that the compressor 1 can normally inhale and exhaust. The hot gas bypass top cover valve 12 will be adjusted to the point where only the hot gas bypass solenoid valve 13 is opened, and the suction pressure sensor 5 indicates a pressure within the range of 0.3 bar to 1 bar.

[0074] 4. Liquid spray cooling solenoid valve control: When the compressor 1 is turned on, the liquid spray cooling solenoid valve 18 is opened, and the liquid spray cooling expansion valve 19 is adjusted to ensure that the compressor exhaust temperature is not higher than +105°C when only the hot gas bypass solenoid valve 13 is turned on. In addition, for the R404a single-stage refrigeration system with an extreme temperature of -40°C in the test chamber and a minimum evaporation temperature of -45°C, the liquid spray cooling expansion valve 19 adopts an R134a expansion valve (operating temperature range is -40°C to +10°C). Under conditions close to extreme temperatures, the liquid spray cooling expansion valve 19 will be mechanically closed to avoid the increase in suction pressure due to the liquid spray cooling circuit, ensuring that the refrigeration circuit reaches a very low suction pressure and evaporation temperature.

[0075] 5. System protection: When the suction pressure sensor 5 indicates that the pressure is higher than 3.5 bar, the refrigeration expansion valve 21, the dehumidification solenoid valve 24, and the hot gas bypass solenoid valve 13 are all forced to close to prevent the compressor 1 from overloading. When the suction pressure sensor 5 indicates that the pressure is lower than 3 bar again, the automatic control is restored. When the exhaust pressure sensor 11 indicates that the pressure is higher than 19 bar, the maximum refrigeration and dehumidification output limit is limited to 50%. When the exhaust pressure sensor 11 indicates that the pressure is lower than 18 bar, the maximum refrigeration and dehumidification output limit is restored to 100%. The system can be kept running under the condition that the condensation is not very good, so as not to trigger the high-pressure switch 7, causing the refrigeration system to alarm and shut down.

[0076] like Figure 1 As shown, the single-stage refrigeration system of the present invention which can steplessly adjust the refrigeration capacity and dehumidification capacity also includes:

[0077] An oil heater 2, which is used to be powered when the compressor 1 is not running to prevent the compressor 1 from accumulating liquid;

[0078] A cylinder head fan 3, the cylinder head fan 3 is used to cool the cylinder head of the compressor 1;

[0079] An oil pressure controller 4, the oil pressure controller 4 is used to detect whether the compressor 1 is short of lubricating oil;

[0080] An air suction vibration-isolating pipe 6, which is used to isolate the vibration of the compressor 1 on the pipeline;

[0081] A high pressure switch 7, which is used to alarm when the exhaust pressure is too high and stop the system;

[0082] A pressure gauge 8, which is used to indicate the exhaust pressure of the system;

[0083] An exhaust vibration-absorbing pipe 9, which is used to isolate the vibration of the compressor 1 on the pipeline;

[0084] An oil separator 10, which is used to separate the oil brought out by the exhaust gas and return it to the compressor 1;

[0085] A water-cooled condenser 14, which is used to provide a heat dissipation source for the refrigeration system and complete the condensation process;

[0086] Safety valve 15, which is used to open and release the pressure when the system high pressure is too high;

[0087] A drying filter 16, the drying filter 16 is used to filter impurities and moisture in the high-pressure liquid;

[0088] A sight glass 17, which is used to observe whether the liquid is sufficient;

[0089] The gas-liquid separator 28 is used to separate the liquid in the system suction gas, and only the gas returns to the compressor 1 to prevent the compressor 1 from being damaged by liquid hammer.

[0090] The single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity can accurately control the refrigeration capacity and dehumidification capacity, greatly reducing the operating cost of the test chamber; since there is no counter-adjustment, the use frequency of components such as the heating system and the humidification system is also greatly reduced, improving the reliability of the test chamber; by controlling the vacancy ratio of the refrigeration solenoid valve and the dehumidification solenoid valve, the refrigeration capacity and dehumidification capacity can be steplessly adjusted; and by detecting the system pressure, hot gas bypass, liquid spray cooling and other means are used to ensure the stable operation of the compressor and the entire system. Only the refrigeration capacity needs to be provided as needed, and the average evaporator temperature is slightly lower than the control temperature in the box, which reduces the possibility of frost on the evaporator. There is basically no frost problem at temperatures above 0°C, and the test chamber can operate at a stable temperature for a long time.

[0091] The single-stage refrigeration system and method for steplessly adjusting the refrigeration capacity and dehumidification capacity of the invention are adopted. The refrigeration circuit and dehumidification circuit can respectively accurately control the refrigeration capacity and dehumidification capacity, thereby eliminating the need for the antagonistic adjustment in the prior art, reducing the use frequency of the heating system and the humidification system, and reducing the operating cost of refrigeration and dehumidification; at the same time, through the stepless adjustment of the refrigeration capacity, the refrigeration capacity is only provided according to the needs, and the average temperature of the evaporator is slightly lower than the control temperature in the box, which reduces the possibility of frost on the evaporator. There is no frost problem at temperatures above 0°C, ensuring that the test box can operate at a stable temperature for a long time, and improving the reliability of the test box. The single-stage refrigeration system and method for steplessly adjusting the refrigeration capacity and dehumidification capacity of the present invention have a simple system structure, convenient maintenance, simple method application, and a very wide range of applications.

[0092] In this specification, the present invention has been described with reference to specific embodiments thereof. However, it is apparent that various modifications and variations may be made without departing from the spirit and scope of the present invention. Therefore, the specification and drawings should be regarded as illustrative rather than restrictive.

Claims

1. A single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity, characterized in that: The system includes: The control subsystem includes an ambient temperature and humidity acquisition device for calculating the cooling capacity and dehumidification capacity according to the ambient temperature and humidity and the target temperature and humidity; The compressor provides the system circulation power through the adiabatic compression process; A refrigeration circuit includes a refrigeration evaporator connected to the compressor through a refrigeration solenoid valve, and the control subsystem controls the refrigeration solenoid valve according to the refrigeration capacity to achieve stepless regulation of the refrigeration capacity; A dehumidification circuit, comprising a dehumidification evaporator connected to the compressor via a dehumidification solenoid valve, wherein the control subsystem controls the dehumidification solenoid valve according to the dehumidification amount to achieve stepless regulation of the dehumidification amount; The control subsystem controls the dehumidification solenoid valve according to the dehumidification amount specifically as follows: The control subsystem calculates and controls the opening time of the dehumidification solenoid valve within a unit cycle according to the dehumidification amount and the humidity control cycle.

2. The single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity according to claim 1, characterized in that: The control subsystem controls the refrigeration solenoid valve according to the refrigeration capacity as follows: The control subsystem calculates and controls the opening time of the refrigeration solenoid valve within a unit cycle according to the refrigeration capacity and the temperature control cycle.

3. The single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity according to claim 2, characterized in that: The refrigeration circuit also includes a refrigeration expansion valve arranged between the refrigeration solenoid valve and the refrigeration evaporator, and the refrigeration expansion valve is used to control the flow of the refrigeration circuit and the evaporation temperature of the refrigeration evaporator.

4. The single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity according to claim 3 is characterized in that: The dehumidification circuit further comprises a dehumidification top cover valve arranged between the dehumidification solenoid valve and the dehumidification evaporator, and the dehumidification top cover valve is used to control the flow of the dehumidification circuit.

5. The single-stage refrigeration system according to any one of claims 1 to 4, characterized in that: It also includes a hot gas bypass circuit, including a hot gas bypass solenoid valve connected to the compressor. When the refrigeration solenoid valve and the dehumidification solenoid valve are both closed, the control subsystem controls the hot gas bypass solenoid valve to open, and uses the hot gas bypass circuit to ensure the suction and exhaust of the compressor.

6. The single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity according to claim 5, characterized in that: It also includes a liquid spray cooling circuit, including a liquid spray cooling solenoid valve connected to the compressor through the hot gas bypass circuit. When the hot gas bypass solenoid valve is opened, the control subsystem controls the liquid spray cooling solenoid valve to open, and utilizes the liquid spray cooling circuit to ensure the exhaust temperature of the compressor.

7. The single-stage refrigeration system with stepless adjustment of refrigeration capacity and dehumidification capacity according to claim 5, characterized in that: The control subsystem also includes a suction pressure sensor arranged on the compressor. When the suction pressure of the compressor is greater than a preset value, the refrigeration circuit, the dehumidification circuit and the hot gas bypass circuit are controlled to be closed.

8. A single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity, characterized in that: The method comprises the following steps: (A) The control subsystem calculates the cooling capacity and dehumidification capacity according to the ambient temperature and humidity and the target temperature and humidity; (B) controlling a refrigeration solenoid valve connected between the compressor and the refrigeration evaporator in the refrigeration circuit according to the refrigeration capacity to achieve stepless regulation of the refrigeration capacity; (C) controlling a dehumidification solenoid valve connected between the compressor and the dehumidification evaporator in the dehumidification circuit according to the dehumidification amount to achieve stepless regulation of the dehumidification amount; The step (B) is specifically: The control subsystem calculates and controls the refrigeration electromagnetic according to the refrigeration capacity and temperature control cycle. The opening time of the valve in a unit cycle.

9. The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity according to claim 8, characterized in that: The step (B) further comprises the following steps: The control subsystem controls the refrigeration expansion valve connected between the refrigeration solenoid valve and the refrigeration evaporator to control the flow rate of the refrigeration circuit and the evaporation temperature of the refrigeration evaporator.

10. The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity according to claim 9, characterized in that: The step (C) is specifically: The control subsystem calculates and controls the opening time of the dehumidification solenoid valve within a unit cycle according to the dehumidification amount and the humidity control cycle.

11. The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity according to claim 10, characterized in that: The step (C) further comprises the following steps: The control subsystem controls the dehumidification top cover valve connected between the dehumidification solenoid valve and the dehumidification evaporator to control the flow of the dehumidification circuit.

12. The single-stage refrigeration method according to any one of claims 8 to 11, characterized in that: The method further comprises the following steps: (D) When the refrigeration solenoid valve and the dehumidification solenoid valve are both closed, the control subsystem controls the hot gas bypass solenoid valve connected to the compressor in the hot gas bypass circuit to open, and utilizes the hot gas bypass circuit to ensure the suction and exhaust of the compressor.

13. The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity according to claim 12, characterized in that: The method further comprises the following steps: (E) When the hot gas bypass solenoid valve is opened, the control subsystem controls the opening of the liquid spray cooling solenoid valve in the liquid spray cooling circuit connected to the compressor through the hot gas bypass circuit, and utilizes the liquid spray cooling circuit to ensure the exhaust temperature of the compressor.

14. The single-stage refrigeration method for steplessly adjusting refrigeration capacity and dehumidification capacity according to claim 13, characterized in that: The method further comprises the following steps: (F) According to the value obtained from the suction pressure sensor provided in the compressor, when the suction pressure of the compressor is greater than a preset value, the control subsystem controls closing of the refrigeration circuit, the dehumidification circuit and the hot gas bypass circuit.

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