Environmental test equipment, refrigeration system control method and control device

Abstract

The invention discloses environment test equipment and a refrigerating system control method and device. The control method comprises the steps that the temperature of an oil pool in a compressor and the exhaust temperature of the compressor are obtained; when the temperature of the oil pool and the exhaust temperature reach the opening condition of the cold side electromagnetic valve, the cold side electromagnetic valve is opened; the initial opening degree of an expansion valve is determined according to the oil pool temperature and the pressure conversion temperature, the opening degree of the expansion valve is adjusted to be the initial opening degree, and the pressure conversion temperature is determined according to the exhaust pressure of the compressor; the current exhaust temperature of the compressor is obtained, and the operation opening degree of the expansion valve is adjusted according to the current exhaust temperature; and every set time period, the steps of obtaining the current exhaust temperature of the compressor and adjusting the operation opening degree of the expansion valve according to the current exhaust temperature are executed again. According to the environment test equipment, the refrigerating system control method and the refrigerating system control device, when the exhaust temperature of the compressor is too high, the motor temperature and the exhaust temperature of the compressor can be accurately reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental testing equipment, and in particular to environmental testing equipment, a refrigeration system control method and a control device. Background Art

[0002] Excessive exhaust temperature of the compressor will cause the lubricating oil temperature to rise and the viscosity to decrease, which may weaken the formation of the oil film, thereby increasing the wear and heat of the moving parts in the compressor. In addition, excessive exhaust temperature may also cause the lubricating oil to carbonize and coke, resulting in cylinder roughness or valve failure, causing compressor failure and affecting the normal operation of the refrigeration system. Therefore, controlling the exhaust temperature of the compressor is crucial to maintaining the normal operation of the refrigeration system. Summary of the invention

[0003] The present invention provides an environmental testing device, a refrigeration system control method and a control device, which can accurately reduce the motor temperature and exhaust temperature of the compressor when the exhaust temperature of the compressor is too high.

[0004] According to one aspect of the present invention, a refrigeration system control method is provided, wherein the refrigeration system comprises at least one compressor and a cold bypass solenoid valve and an expansion valve connected to the compressor;

[0005] The control method comprises:

[0006] Acquiring the oil pool temperature in the compressor and the exhaust temperature of the compressor;

[0007] When the oil pool temperature and the exhaust gas temperature reach the cold bypass solenoid valve opening condition, opening the cold bypass solenoid valve;

[0008] Determining the initial opening of the expansion valve according to the oil pool temperature and the pressure conversion temperature and adjusting the opening of the expansion valve to the initial opening, wherein the pressure conversion temperature is determined according to the exhaust pressure of the compressor;

[0009] Acquiring the current exhaust temperature of the compressor, and adjusting the operating opening of the expansion valve according to the current exhaust temperature;

[0010] At every set time period, the process returns to the step of obtaining the current exhaust temperature of the compressor and adjusting the operating opening of the expansion valve according to the current exhaust temperature.

[0011] Optionally, the cold bypass solenoid valve opening conditions include:

[0012] The difference between the exhaust temperature and the oil pool temperature is less than the first set temperature and greater than 0, and the exhaust temperature is greater than the second set temperature.

[0013] Optionally, adjusting the operating opening of the expansion valve according to the current exhaust temperature includes:

[0014] When the current exhaust temperature is less than or equal to a third set temperature, reducing the operating opening of the expansion valve;

[0015] When the current exhaust gas temperature is greater than the third set temperature, the operating opening of the expansion valve is increased.

[0016] Optionally, the acquiring the current exhaust temperature of the compressor and adjusting the operating opening of the expansion valve according to the current exhaust temperature includes:

[0017] Obtaining a current exhaust temperature, a current oil pool temperature, and a current pressure conversion temperature of the compressor;

[0018] The operating opening of the expansion valve is adjusted according to the current exhaust gas temperature, the current oil pool temperature and the current pressure conversion temperature.

[0019] Optionally, adjusting the operating opening of the expansion valve according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature includes:

[0020] Determining a first influencing factor according to the current exhaust temperature, the current oil pool temperature and the target oil temperature superheat;

[0021] Determining a second influencing factor according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature;

[0022] determining a target opening of the expansion valve according to a current opening of the expansion valve, the first influencing factor, and the second influencing factor;

[0023] The current opening of the expansion valve is adjusted to the target opening.

[0024] Optionally, determining the target opening of the expansion valve according to the current opening of the expansion valve, the first influencing factor, and the second influencing factor includes:

[0025] The target opening of the expansion valve is determined according to the following formula:

[0026] P 目标开度 =P 当前开度 +△P*K;

[0027] Among them, P 目标开度 is the target opening of the expansion valve, P 当前开度 is the current opening of the expansion valve, K is the first influencing factor, and ΔP is the second influencing factor.

[0028] Optionally, determining the second influencing factor according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature includes:

[0029] Determining the current oil temperature superheat according to the difference between the current oil pool temperature and the current pressure conversion temperature;

[0030] The second influencing factor is determined according to the current oil temperature superheat, the current exhaust temperature and the influencing factor table.

[0031] Optionally, the refrigeration system control method further includes:

[0032] If it is detected that the exhaust temperature of the compressor is greater than a fourth set temperature, the opening of the expansion valve is adjusted to the maximum opening of the expansion valve.

[0033] According to another aspect of the present invention, a refrigeration system control device is provided, wherein the refrigeration system comprises at least one compressor and a cold bypass solenoid valve and an expansion valve connected to the compressor;

[0034] The refrigeration system control device comprises: a temperature acquisition module, a solenoid valve control module and an expansion valve control module;

[0035] The temperature acquisition module is used to acquire the oil pool temperature in the compressor and the exhaust temperature of the compressor, and is also used to acquire the current exhaust temperature of the compressor at every set time period;

[0036] The solenoid valve control module is used to open the cold bypass solenoid valve when the oil pool temperature and the exhaust gas temperature reach the cold bypass solenoid valve opening condition;

[0037] The expansion valve control module is used to determine the initial opening of the expansion valve according to the oil pool temperature and the pressure conversion temperature and adjust the opening of the expansion valve to the initial opening, and is also used to adjust the operating opening of the expansion valve according to the current exhaust temperature, wherein the pressure conversion temperature is determined according to the exhaust pressure of the compressor.

[0038] According to another aspect of the present invention, an environmental testing device is provided. The environmental testing device includes a refrigeration system and a refrigeration system control device provided by any embodiment of the present invention.

[0039] The embodiment of the present invention provides a control method for a refrigeration system, wherein the refrigeration system includes at least one compressor and a cold bypass solenoid valve and an expansion valve connected to the compressor. The control method provided by the embodiment includes: first obtaining the exhaust temperature and oil pool temperature of the compressor, and then opening the cold bypass solenoid valve when it is determined that the exhaust temperature and the oil pool temperature reach the opening condition of the cold bypass solenoid valve. Then, the initial opening of the expansion valve is determined according to the oil pool temperature and the pressure conversion temperature, and the opening of the expansion valve is adjusted to the initial opening. Finally, the current exhaust temperature of the compressor is obtained once every set time period, and the operating opening of the expansion valve is adjusted according to the current exhaust temperature. The embodiment determines whether it is necessary to open the cold bypass solenoid valve according to the oil pool temperature and the exhaust temperature, thereby improving the accuracy of determining the opening time of the cold bypass solenoid valve, and avoiding the cold bypass solenoid valve from opening in time and failing to reduce the temperature of the compressor in time. The embodiment determines the initial opening of the expansion valve according to the oil pool temperature and the pressure conversion temperature, and the pressure conversion temperature can reflect the working condition of the refrigeration system, and obtains the current exhaust temperature of the compressor once every set time period, and adjusts the operating opening of the expansion valve according to the current exhaust temperature, thereby timely reducing the motor temperature and exhaust temperature of the motor in the compressor. In summary, the refrigeration system control method provided in this embodiment can accurately reduce the motor temperature and exhaust temperature of the compressor when the exhaust temperature of the compressor is too high.

[0040] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0042] Figure 1 is a structural schematic diagram of a refrigeration system provided according to an embodiment of the present invention;

[0043] Figure 2 is a flow chart of a refrigeration system control method provided according to an embodiment of the present invention;

[0044] Figure 3 It is a structural schematic diagram of a refrigeration system control device provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0046] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0047] Figure 1 is a schematic diagram of a refrigeration system according to an embodiment of the present invention, with reference to Figure 1 The refrigeration system provided in this embodiment includes at least one compressor 110, and a cold-side solenoid valve 120 and an expansion valve 130 connected to the compressor 110. The refrigeration system may include two compressors 110, and a cold-side solenoid valve 120 and an expansion valve 130 correspondingly connected to each compressor 110. The refrigeration system may also include a first temperature sensor 210, a second temperature sensor 220 and a pressure sensor (not shown in the figure) corresponding to the number of compressors 110, the first temperature sensor 210 detects the oil pool temperature in the oil pool of the compressor 110, the second temperature sensor 220 detects the exhaust temperature at the exhaust port of the compressor 110, and the pressure sensor detects the exhaust pressure at the exhaust port of the compressor 110. The compressor 110 may be a high-pressure chamber compressor, and the expansion valve 130 may be an electronic expansion valve.

[0048] Figure 2 is a flow chart of a refrigeration system control method provided according to an embodiment of the present invention, with reference to Figure 1 and Figure 2 , the control method provided in this embodiment includes the following steps:

[0049] S110, obtaining the oil pool temperature in the compressor and the exhaust temperature of the compressor.

[0050] Specifically, the oil in the oil pool of the compressor 110 may be lubricating oil, and the oil pool temperature may be obtained according to the first temperature sensor 210 , and the exhaust gas temperature may be obtained according to the second temperature sensor 220 .

[0051] S120: When the oil pool temperature and the exhaust gas temperature reach the opening conditions of the cold bypass solenoid valve, the cold bypass solenoid valve is opened.

[0052] Specifically, after the cold bypass solenoid valve 120 is opened, the cold liquid in the refrigeration system can flow in the cold bypass branch, thereby reducing the motor temperature of the motor in the compressor 110 and the exhaust temperature at the exhaust port of the compressor 110, avoiding excessively high exhaust temperature and reducing the service life of the compressor 110.

[0053] The opening conditions of the cold bypass solenoid valve include the limitations on the oil pool temperature and the exhaust temperature. This embodiment determines whether the cold bypass solenoid valve 120 needs to be opened based on the oil pool temperature and the exhaust temperature. This can improve the accuracy of determining the opening timing of the cold bypass solenoid valve 120 and avoid the problem of the cold bypass solenoid valve 120 being opened untimely or prematurely due to only determining whether the cold bypass solenoid valve 120 needs to be opened based on the exhaust temperature.

[0054] S130, determining the initial opening of the expansion valve according to the oil pool temperature and the pressure conversion temperature, and adjusting the opening of the expansion valve to the initial opening.

[0055] The pressure conversion temperature is determined according to the exhaust pressure of the compressor.

[0056] Specifically, before executing step S130, the pressure detected by the pressure sensor at the exhaust port of the compressor 110 in the refrigeration system is first obtained, and then the pressure is converted into a saturation temperature corresponding to the pressure sensor. The converted saturation temperature is the pressure conversion temperature. The pressure conversion temperature can reflect the operating conditions in the refrigeration system. Exemplarily, the operating conditions include the temperature in the evaporator, the valve opening of the manual throttle valve, and the flow rate of the liquid in the cold bypass.

[0057] The initial opening refers to the opening of the expansion valve 130 when it is just started. The initial opening of the expansion valve 130 can be determined according to the difference between the oil pool temperature and the pressure conversion temperature. For example, the difference between the oil pool temperature and the pressure conversion temperature is recorded as T 油温过热度 , refer to Table 1, when T 油温过热度 When the temperature ranges are different, the initial opening of the expansion valve 130 will be different. The unit of the initial opening of the expansion valve 130 is the international unit of opening. 油温过热度 When the value of T is larger, the initial opening of the expansion valve 130 can be larger, and a larger initial opening can quickly reduce the temperature of the compressor 110. 油温过热度The corresponding temperature range determines the initial opening of the expansion valve 130 , so that the exhaust temperature and the motor temperature of the compressor 110 can be accurately adjusted.

[0058] Table 1

[0059]

[0060] S140: Obtain the current exhaust temperature of the compressor, and adjust the operating opening of the expansion valve according to the current exhaust temperature.

[0061] Specifically, the operating opening refers to the opening after the expansion valve 130 is in operation. After the solenoid valve 120 and the expansion valve 130 are turned on, the current exhaust temperature of the compressor 110 is obtained once every set time period, and the operating opening of the expansion valve 130 is adjusted according to the current exhaust temperature. After obtaining the current exhaust temperature, if it is detected that the current exhaust temperature is too high, the operating opening of the expansion valve 130 can be appropriately increased to quickly reduce the temperature of the compressor 110. After the temperature of the compressor 110 is reduced, the motor temperature of the motor in the compressor 110 will be reduced, and the exhaust temperature of the exhaust port will be reduced. If it is detected that the current exhaust temperature is relatively low, the operating opening of the expansion valve 130 can be appropriately reduced. It can be seen that the refrigeration system control method provided in this embodiment can accurately adjust the motor temperature and exhaust temperature in the compressor 110.

[0062] S150. After setting the time period, return to step S140.

[0063] Specifically, the set time period can be 30s. Every set time period, the current exhaust temperature of the compressor 110 is obtained once, and the operating opening of the expansion valve 130 is adjusted according to the current exhaust temperature. The operating opening of the expansion valve 130 can be flexibly adjusted according to the change of the exhaust temperature to avoid the operating opening of the expansion valve 130 always maintaining a fixed opening value, causing the temperature of the compressor 110 to not be reduced in time, and other problems.

[0064] It should be noted that, in the process of controlling the refrigeration system, when it is detected that the oil pool temperature and the exhaust temperature do not meet the opening conditions of the cold bypass solenoid valve, the cold bypass solenoid valve 120 can be closed and the control process can be ended. When the refrigeration system includes two compressors 110, the control method provided in this embodiment can be used to simultaneously control the temperatures of the two compressors 110. The refrigeration system control method provided in this embodiment can adjust the operating opening of the expansion valve when the current exhaust temperature is less than the seventh set temperature.

[0065] This embodiment provides a control method for a refrigeration system. The refrigeration system includes at least one compressor, a cold bypass solenoid valve connected to the compressor, and an expansion valve. The control method provided by this embodiment includes: first obtaining the exhaust temperature and the oil sump temperature of the compressor, and then opening the cold bypass solenoid valve when it is determined that the exhaust temperature and the oil sump temperature reach the opening condition of the cold bypass solenoid valve. Then, determine the initial opening degree of the expansion valve according to the oil sump temperature and the pressure conversion temperature, and adjust the opening degree of the expansion valve to the initial opening degree. Finally, every set time period, obtain the current exhaust temperature of the compressor once, and adjust the operating opening degree of the expansion valve according to the current exhaust temperature. This embodiment determines whether to open the cold bypass solenoid valve based on the oil sump temperature and the exhaust temperature, improving the accuracy of determining the opening timing of the cold bypass solenoid valve and avoiding the situation where the cold bypass solenoid valve fails to open in time and cannot reduce the temperature of the compressor in time. This embodiment determines the initial opening degree of the expansion valve according to the oil sump temperature and the pressure conversion temperature. The pressure conversion temperature can reflect the working condition of the refrigeration system. And every set time period, obtain the current exhaust temperature of the compressor once, and adjust the operating opening degree of the expansion valve according to the current exhaust temperature, so as to reduce the motor temperature and the exhaust temperature of the motor in the compressor in time. In summary, the refrigeration system control method provided by this embodiment can accurately reduce the motor temperature and the exhaust temperature of the compressor when the exhaust temperature of the compressor is too high.

[0066] Optionally, the opening condition of the cold bypass solenoid valve includes: the difference between the exhaust temperature and the oil sump temperature is less than the first set temperature and greater than 0, and the exhaust temperature is greater than the second set temperature.

[0067] Specifically, when it is detected that the following conditions are simultaneously satisfied, the cold bypass solenoid valve is opened:

[0068] 0 < T 排气温度 - T 油池温度 < Tc, and T 排气温度 >Tp;

[0069] Wherein, T 排气温度 represents the exhaust temperature at the exhaust port of the compressor, T 油池温度 is the oil sump temperature of the oil sump in the compressor, Tc represents the first set temperature, and Tp represents the second set temperature. The first set temperature and the second set temperature can be set according to actual needs. Exemplarily, the first set temperature can be 8°C, and the second set temperature can be 100°C. The opening condition of the cold bypass solenoid valve is determined according to the exhaust temperature and the relationship between the exhaust temperature and the oil sump temperature, which can improve the accuracy of the opening timing of the cold bypass solenoid valve, and thus can accurately control the motor temperature and the exhaust temperature of the compressor.

[0070] Optionally, the operating opening of the expansion valve is adjusted according to the current exhaust temperature, including: when the current exhaust temperature is less than or equal to the third set temperature, reducing the operating opening of the expansion valve; when the current exhaust temperature is greater than the third set temperature, increasing the operating opening of the expansion valve.

[0071] Specifically, when the current exhaust temperature is less than or equal to the third set temperature, it means that the temperature in the compressor is not particularly high, and the operating opening of the expansion valve can be appropriately reduced to reduce the power consumption in the refrigeration system. When the current exhaust temperature is greater than the third set temperature, it means that the temperature in the compressor is high. At this time, the operating opening of the expansion valve can be appropriately increased to reduce the temperature in the compressor at a faster speed, thereby quickly reducing the motor temperature of the motor in the compressor and the exhaust temperature. It can be seen that this embodiment can adjust the operating opening of the expansion valve according to the relationship between the current exhaust temperature and the third set temperature to ensure that the compressor can work normally, avoid the compressor from working in a high temperature environment for a long time, and increase the service life of the compressor. The third set temperature can be set according to user needs. For example, the third set temperature can be 100°C.

[0072] Optionally, the current exhaust temperature of the compressor is obtained, and the operating opening of the expansion valve is adjusted according to the current exhaust temperature, including: obtaining the current exhaust temperature of the compressor, the current oil pool temperature and the current pressure conversion temperature; adjusting the operating opening of the expansion valve according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature.

[0073] Specifically, obtaining the current pressure conversion temperature includes: obtaining the current pressure of the exhaust port of the compressor, and determining the current pressure conversion temperature according to the current pressure.

[0074] This embodiment adjusts the operating opening of the expansion valve according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature, which can improve the accuracy of adjusting the operating opening of the expansion valve, thereby improving the accuracy of adjusting the motor temperature and the exhaust temperature in the compressor.

[0075] Optionally, the operating opening of the expansion valve is adjusted according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature, including: determining a first influencing factor according to the current exhaust temperature, the current oil pool temperature and the target oil temperature superheat; determining a second influencing factor according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature; determining the target opening of the expansion valve according to the current opening of the expansion valve, the first influencing factor and the second influencing factor; and adjusting the current opening of the expansion valve to the target opening.

[0076] Specifically, T 油温过热度差值 =T 当前排气温度 -T 当前油池温度 -T 目标油温过热度 , where T 当前排气温度 is the current exhaust temperature, T当前油池温度 is the current oil pool temperature, T 目标油温过热度 is the target oil temperature superheat, which can be calculated based on T 油温过热度差值 The first influencing factor is determined by the interval where the current oil pool temperature minus the current pressure conversion temperature and the current exhaust temperature. The second influencing factor can be jointly determined based on the difference between the current oil pool temperature and the current pressure conversion temperature and the current exhaust temperature. Finally, the target opening of the expansion valve is jointly determined based on the current opening, the first influencing factor and the second influencing factor. The refrigeration system control method provided in this embodiment, when adjusting the motor temperature and exhaust temperature of the compressor, jointly determines the operating opening of the expansion valve based on a variety of influencing parameters, thereby further improving the accuracy of adjusting the motor temperature and exhaust temperature of the compressor. Among them, T 目标油温过热度 It can be set according to actual needs. 目标油温过热度 It can be a fixed value throughout the process of controlling the refrigeration system, or it can be adaptively adjusted in the process of controlling the operating opening of the expansion valve of the refrigeration system.

[0077] Optionally, determining a target opening of the expansion valve according to the current opening of the expansion valve, the first influencing factor, and the second influencing factor includes:

[0078] Determine the target opening of the expansion valve according to the following formula:

[0079] P 目标开度 =P 当前开度 +△P*K;

[0080] Among them, P 目标开度 is the target opening of the expansion valve, P 当前开度 is the current opening of the expansion valve, K is the first influencing factor, and △P is the second influencing factor.

[0081] Specifically, the value of K can be: T 油温过热度差值 =T 当前排气温度 -T 当前油池温度 -T 目标油温过热度 , when T 油温过热度差值 >5th set temperature, K takes the first set value, when T 油温过热度差值 <the sixth set temperature, K takes the second set value. When the sixth set temperature ≤T 油温过热度差值 ≤ the fifth set temperature, K takes the third set value. The fifth set temperature may be 1°C, the sixth set temperature may be -1°C, the first set value may be 1.5, the second set value may be 0.8, and the third set value may be 1.

[0082] Optionally, the second influencing factor is determined based on the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature, including: determining the current oil temperature superheat based on the difference between the current oil pool temperature and the current pressure conversion temperature; determining the second influencing factor based on the current oil temperature superheat, the current exhaust temperature and the influencing factor table.

[0083] Specifically, the influencing factor table includes multiple superheat intervals, multiple exhaust temperature intervals, and multiple influencing factors.

[0084] The second influencing factor is determined based on the current oil temperature superheat, the current exhaust temperature and the influencing factor table, including:

[0085] The superheat interval to which the current oil temperature superheat belongs is determined according to the current oil temperature superheat, and the exhaust temperature interval to which the current exhaust temperature belongs is determined according to the current exhaust temperature; then the influencing factor corresponding to the determined superheat interval and exhaust temperature interval is used as the second influencing factor.

[0086] The influence factor table can be shown in Table 2 below, where T1<5 and T2>20, and the corresponding temperature unit in Table 2 is °C:

[0087] Table 2

[0088]

[0089] It should be noted that Table 2 only shows the second influencing factors corresponding to different superheat intervals and exhaust temperature intervals by way of example. In practical applications, the superheat intervals and exhaust temperature intervals can be further divided according to actual needs, and the specific value of the second influencing factor can be adjusted.

[0090] The influencing factor table provided in this embodiment includes multiple influencing factors. It can be seen that when the superheat interval to which the current oil temperature superheat belongs and the exhaust temperature interval to which the current exhaust temperature belongs are different, the second influencing factor will be different. It can be seen that this embodiment can accurately control the operating opening of the expansion valve according to the current oil temperature superheat and the current exhaust temperature, thereby accurately controlling the motor temperature and exhaust temperature of the compressor.

[0091] Optionally, the refrigeration system control method further includes: if it is detected that the exhaust temperature of the compressor is greater than a fourth set temperature, adjusting the opening of the expansion valve to the maximum opening of the expansion valve.

[0092] Specifically, the fourth set temperature may be 120°C, and the maximum opening of the expansion valve may be 480°C. In the process of controlling the refrigeration system, if it is detected that the exhaust temperature of the compressor is greater than the fourth set temperature, the opening of the expansion valve is directly adjusted to the maximum opening of the expansion valve, and the temperature of the motor in the compressor and the exhaust temperature of the compressor are reduced at the fastest speed until it is detected that the exhaust temperature of the compressor is less than the seventh set temperature. The seventh set temperature may be 110°C.

[0093] Figure 3 is a schematic diagram of a refrigeration system control device according to an embodiment of the present invention, with reference to Figure 3The refrigeration system control device provided in this embodiment includes: a temperature acquisition module 310, a solenoid valve control module 320 and an expansion valve control module 330; the temperature acquisition module 310 is used to obtain the oil pool temperature in the compressor and the exhaust temperature of the compressor, and is also used to obtain the current exhaust temperature of the compressor at set time intervals; the solenoid valve control module 320 is used to open the cold bypass solenoid valve when the oil pool temperature and the exhaust temperature reach the opening condition of the cold bypass solenoid valve; the expansion valve control module 330 is used to determine the initial opening of the expansion valve according to the oil pool temperature and the pressure conversion temperature and adjust the opening of the expansion valve to the initial opening, and is also used to adjust the operating opening of the expansion valve according to the current exhaust temperature, wherein the pressure conversion temperature is determined according to the exhaust pressure of the compressor.

[0094] The refrigeration system control device provided in this embodiment has corresponding beneficial effects with the refrigeration system control method provided in any embodiment of the present invention. For technical details not elaborated in this embodiment, please refer to the refrigeration system control method provided in any embodiment of the present invention.

[0095] This embodiment further provides an environmental testing device, which includes a refrigeration system and a refrigeration system control device provided by any embodiment of the present invention.

[0096] Specifically, the environmental test equipment of this embodiment includes a box, a refrigeration system, a water system and a control system. The box is mainly composed of heat insulation materials. The control system includes a touch screen, a PLC and its expansion modules. The box includes a constant temperature room, and the temperature in the constant temperature room is maintained within a constant temperature range. The refrigeration system control device can be located in the control system. The environmental test equipment provided in this embodiment can accurately control the motor temperature and exhaust temperature in the compressor in the environmental test equipment, and can ensure the normal operation of the compressor.

[0097] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0098] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A refrigeration system control method, characterized in that: The refrigeration system comprises at least one compressor and a cold bypass solenoid valve and an expansion valve connected to the compressor; The control method comprises: Acquiring the oil pool temperature in the compressor and the exhaust temperature of the compressor; When the oil pool temperature and the exhaust gas temperature reach the cold bypass solenoid valve opening condition, opening the cold bypass solenoid valve; Determining the initial opening of the expansion valve according to the oil pool temperature and the pressure conversion temperature and adjusting the opening of the expansion valve to the initial opening, wherein the pressure conversion temperature is determined according to the exhaust pressure of the compressor; Acquiring the current exhaust temperature of the compressor, and adjusting the operating opening of the expansion valve according to the current exhaust temperature; At every set time period, the process returns to the step of obtaining the current exhaust temperature of the compressor and adjusting the operating opening of the expansion valve according to the current exhaust temperature.

2. The refrigeration system control method according to claim 1, characterized in that: The cold bypass solenoid valve opening conditions include: The difference between the exhaust temperature and the oil pool temperature is less than the first set temperature and greater than 0, and the exhaust temperature is greater than the second set temperature.

3. The refrigeration system control method according to claim 1, characterized in that: The step of adjusting the operating opening of the expansion valve according to the current exhaust gas temperature includes: When the current exhaust temperature is less than or equal to a third set temperature, reducing the operating opening of the expansion valve; When the current exhaust gas temperature is greater than the third set temperature, the operating opening of the expansion valve is increased.

4. The refrigeration system control method according to claim 1, characterized in that: The obtaining of the current exhaust temperature of the compressor and adjusting the operating opening of the expansion valve according to the current exhaust temperature includes: Obtaining a current exhaust temperature, a current oil pool temperature, and a current pressure conversion temperature of the compressor; The operating opening of the expansion valve is adjusted according to the current exhaust gas temperature, the current oil pool temperature and the current pressure conversion temperature.

5. The refrigeration system control method according to claim 4, characterized in that: The adjusting the operating opening of the expansion valve according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature includes: Determining a first influencing factor according to the current exhaust temperature, the current oil pool temperature and the target oil temperature superheat; Determining a second influencing factor according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature; determining a target opening of the expansion valve according to a current opening of the expansion valve, the first influencing factor, and the second influencing factor; The current opening of the expansion valve is adjusted to the target opening.

6. The refrigeration system control method according to claim 5, characterized in that: The determining the target opening of the expansion valve according to the current opening of the expansion valve, the first influencing factor and the second influencing factor comprises: The target opening of the expansion valve is determined according to the following formula: P 目标开度 =P 当前开度 +△P*K; Among them, P 目标开度 is the target opening of the expansion valve, P 当前开度 is the current opening of the expansion valve, K is the first influencing factor, and ΔP is the second influencing factor.

7. The refrigeration system control method according to claim 5, characterized in that: The determining of the second influencing factor according to the current exhaust temperature, the current oil pool temperature and the current pressure conversion temperature includes: Determining the current oil temperature superheat according to the difference between the current oil pool temperature and the current pressure conversion temperature; The second influencing factor is determined according to the current oil temperature superheat, the current exhaust temperature and the influencing factor table.

8. The refrigeration system control method according to claim 1, characterized in that: The refrigeration system control method further includes: If it is detected that the exhaust temperature of the compressor is greater than a fourth set temperature, the opening of the expansion valve is adjusted to the maximum opening of the expansion valve.

9. A refrigeration system control device, characterized in that: The refrigeration system comprises at least one compressor and a cold bypass solenoid valve and an expansion valve connected to the compressor; The refrigeration system control device comprises: a temperature acquisition module, a solenoid valve control module and an expansion valve control module; The temperature acquisition module is used to acquire the oil pool temperature in the compressor and the exhaust temperature of the compressor, and is also used to acquire the current exhaust temperature of the compressor at every set time period; The solenoid valve control module is used to open the cold bypass solenoid valve when the oil pool temperature and the exhaust gas temperature reach the cold bypass solenoid valve opening condition; The expansion valve control module is used to determine the initial opening of the expansion valve according to the oil pool temperature and the pressure conversion temperature and adjust the opening of the expansion valve to the initial opening, and is also used to adjust the operating opening of the expansion valve according to the current exhaust temperature, wherein the pressure conversion temperature is determined according to the exhaust pressure of the compressor.

10. An environmental testing device, characterized in that: The invention comprises a refrigeration system and the refrigeration system control device as claimed in claim 9.

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