An oil cooling system and oil cooling control method

Abstract

This invention discloses an oil cooling system and an oil cooling control method. The oil cooling system includes a compressor, an oil separator, an oil cooler, and an evaporator. The oil outlet of the oil separator is connected to the oil return port of the compressor via a first pipeline and a second pipeline connected in parallel. A first valve is installed on the first pipeline. The second pipeline passes through the oil cooler, and a second valve is installed on the pipeline between the oil outlet of the oil separator and the oil inlet of the oil cooler. The first refrigerant outlet of the evaporator is connected to the refrigerant inlet of the oil cooler, and the first refrigerant inlet of the evaporator is connected to the refrigerant outlet of the oil cooler. This invention uses liquid taken from the evaporator as the cold source for the oil cooler, and achieves oil cooling through refrigerant self-circulation. Related components and pipelines can be integrated into the whole machine without additional piping. Furthermore, the refrigerant returns to the evaporator to continue participating in the refrigerant circulation after cooling the lubricating oil, without losing unit heat and avoiding a decrease in unit energy efficiency due to oil cooling.

Description

Technical Field

[0001] This invention relates to the field of generator set technology, and more specifically, to an oil cooling system and an oil cooling control method. Background Technology

[0002] For screw-type heat pump units, the flow rate and temperature control of the refrigerant oil are two key factors ensuring stable operation, especially oil temperature control. Under high-temperature conditions, the lubricating oil viscosity can easily become too low, failing to form a suitable oil film, affecting sealing performance, and even leading to partial decomposition of the lubricating oil. Due to the unique structure of heat pump units, regardless of the refrigerant used, there is a general problem of high exhaust and oil temperatures, thus requiring specific cooling measures for the oil.

[0003] Currently, there are generally two types of oil cooling system configurations for screw heat pump units:

[0004] (1) The water-cooled oil cooler is used. In addition to the conventional chilled water supply and return water and cooling water supply and return water pipelines, this structure also requires the oil cooler to be equipped with a corresponding oil cooling supply and return water pipeline system (such as water pump and group control), which increases the workload of the project. Moreover, not all customers can be equipped with the corresponding system, which has limitations.

[0005] (2) A differential pressure refrigerant cooling method is adopted, in which liquid is drawn from the condenser and throttled, and the throttled working fluid is used to cool the oil circuit. Although this method does not require piping in the engineering, it loses heat and reduces the energy efficiency of the heat pump unit.

[0006] There is currently no effective solution to the problem that oil cooling methods in existing technologies require additional piping or reduce unit energy efficiency. Summary of the Invention

[0007] This invention provides an oil cooling system and an oil cooling control method to at least solve the problems of existing oil cooling methods requiring additional piping or reducing unit energy efficiency.

[0008] To address the aforementioned technical problems, embodiments of the present invention provide an oil cooling system, comprising: a compressor, an oil separator, an oil cooler, and an evaporator;

[0009] The oil outlet of the oil separator is connected to the oil return port of the compressor through a first pipeline and a second pipeline connected in parallel.

[0010] A first valve is installed on the first pipeline;

[0011] The second pipeline passes through the oil cooler, and a second valve is installed in the second pipeline between the oil outlet of the oil separator and the oil inlet of the oil cooler;

[0012] The first refrigerant outlet of the evaporator is connected to the refrigerant inlet of the oil cooler, and the first refrigerant inlet of the evaporator is connected to the refrigerant outlet of the oil cooler.

[0013] Optionally, an oil return temperature sensor is installed at the oil return port of the compressor.

[0014] Optionally, the evaporator is a falling film evaporator.

[0015] Optionally, a refrigerant pump and a third valve are connected in parallel on the pipeline between the refrigerant outlet of the oil cooler and the first refrigerant inlet of the evaporator.

[0016] Optionally, the evaporator further includes a second refrigerant outlet, which is connected to the refrigerant inlet of the condenser via a fourth valve.

[0017] Optionally, the center of gravity of the oil cooler is lower than that of the evaporator; the first refrigerant outlet of the evaporator is located at the lowest point of the evaporator; and the refrigerant outlet of the oil cooler is located at the upper part of the oil cooler.

[0018] This invention also provides an oil cooling control method, applied to the oil cooling system described in this invention, the method comprising:

[0019] Monitor the return oil temperature;

[0020] The opening degree of the first valve and the second valve is controlled according to the oil return temperature so that the oil return temperature is equal to the preset oil temperature.

[0021] Optionally, controlling the opening degree of the first valve and the second valve according to the return oil temperature includes:

[0022] If the return oil temperature is greater than the preset oil temperature, then reduce the opening of the first valve and / or increase the opening of the second valve;

[0023] If the return oil temperature is lower than the preset oil temperature, then increase the opening of the first valve and / or decrease the opening of the second valve;

[0024] If the return oil temperature is equal to the preset oil temperature, then the current opening degree of the first valve and the second valve remains unchanged.

[0025] Optionally, the target opening degree of the first valve can be determined according to the following formula:

[0026] Y = Y0 + [(T a -T)+k]×m,

[0027] Where Y represents the target opening degree of the first valve, Y0 represents the initial opening degree of the first valve, and Ta The preset oil temperature is represented by T, the current return oil temperature is represented by k, and m is represented by the valve step coefficient.

[0028] Optionally, the target opening degree of the second valve can be determined according to the following formula:

[0029] X = X0 + [(TT) a )+k]×m,

[0030] Where X represents the target opening degree of the second valve, X0 represents the initial opening degree of the second valve, and T a The preset oil temperature is represented by T, the current return oil temperature is represented by k, and m is represented by the valve step coefficient.

[0031] Optionally, the above methods also include:

[0032] When the compressor is running normally, turn off the refrigerant pump, open the third valve, and close the fourth valve;

[0033] When the unit's demand load is less than the preset load, the compressor is turned off, the refrigerant pump is turned on, the third valve is closed, the fourth valve is opened, and the opening degree of the throttling element between the evaporator and the condenser is controlled so that the pressure difference between the evaporator and the condenser is within the preset range.

[0034] This invention also provides a non-volatile computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method described in this invention.

[0035] By applying the technical solution of this invention, liquid is taken from the evaporator as the cold source for the oil cooler, and oil cooling is achieved through refrigerant self-circulation. Related components and piping can be integrated into the entire unit, facilitating installation and use in engineering projects without the need for additional piping. Furthermore, the refrigerant returns to the evaporator after cooling the lubricating oil to continue participating in the refrigerant circulation. Oil cooling does not lose heat from the unit, avoiding the reduction in unit energy efficiency due to oil cooling. This solves the problem of existing oil cooling methods requiring additional piping or reducing unit energy efficiency. In addition, the first and second valves ensure that the return oil temperature is maintained at a suitable level. Attached Figure Description

[0036] Figure 1 This is a schematic diagram of the oil cooling system provided in Embodiment 1 of the present invention;

[0037] Figure 2 This is another schematic diagram of the oil cooling system provided in Embodiment 1 of the present invention;

[0038] Figure 3 This is a flowchart of the oil cooling control method provided in Embodiment 2 of the present invention;

[0039] Figure 4 This is a valve control flowchart provided in Embodiment 2 of the present invention;

[0040] Figure 5 This is a schematic diagram of the hardware structure of the electronic device provided in Embodiment 4 of the present invention;

[0041] Explanation of reference numerals in the attached figures:

[0042] 1. Compressor; 2. Oil separator; 3. Condenser; 4. Throttling element; 5. Evaporator; 6. Oil cooler; 21. First valve; 22. Second valve; 23. Oil return temperature sensor; 7. Refrigerant pump; 8. Third valve; 9. Fourth valve. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0044] It should be noted that the terms "first," "second," etc., used in the specification, claims, and drawings of this invention 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 the invention 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, system, 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.

[0045] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0046] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0047] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0048] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0049] The optional embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0050] Example 1

[0051] This embodiment provides an oil cooling system that can be applied to heat pump units.

[0052] Figure 1 This is a schematic diagram of the oil cooling system provided in Embodiment 1 of the present invention, as shown below. Figure 1 As shown, the air conditioning unit includes: a compressor 1, an oil separator 2, a condenser 3, a throttling element 4, and an evaporator 5 connected in sequence. The high-temperature and high-pressure refrigerant discharged from the compressor 1 carries lubricating oil into the oil separator 2. The oil separator 2 separates the refrigerant and lubricating oil. The lubricating oil coming out of the oil separator 2 returns to the oil return port of the compressor 1. The refrigerant coming out of the oil separator 2 passes through the condenser 3, the throttling element 4, and the evaporator 5 in sequence before returning to the suction port of the compressor 1, completing one refrigerant cycle.

[0053] The oil cooling system includes a compressor 1, an oil separator 2, an oil cooler 6, and an evaporator 5. The oil outlet of the oil separator 2 is connected to the oil return port of the compressor 1 via a first pipeline and a second pipeline connected in parallel. A first valve 21 is installed on the first pipeline. The second pipeline passes through the oil cooler 6, and a second valve 22 is installed on the section of the second pipeline between the oil outlet of the oil separator 2 and the oil inlet of the oil cooler 6. The first refrigerant outlet of the evaporator 5 is connected to the refrigerant inlet of the oil cooler 6, and the first refrigerant inlet of the evaporator 5 is connected to the refrigerant outlet of the oil cooler 6.

[0054] Low-temperature liquid refrigerant is drawn from evaporator 5 through the first refrigerant outlet and enters oil cooler 6 to cool the lubricating oil. After exchanging heat with the lubricating oil, the liquid refrigerant vaporizes and returns to evaporator 5 through the first refrigerant inlet to continue participating in the refrigerant cycle. Utilizing the natural falling of liquids and the natural rising of gases, a spontaneous refrigerant circulation occurs between evaporator 5 and oil cooler 6, achieving cooling of the lubricating oil and ensuring that the temperature of the heat exchange medium in the oil cooler remains relatively constant, resulting in a stable cooling effect for the lubricating oil.

[0055] If the lubricating oil temperature is too high, the oil viscosity will be too low, failing to form a suitable oil film and affecting the unit's operational stability. If the lubricating oil temperature is too low, the oil viscosity will be too high, causing excessive compressor power consumption. Furthermore, when the return oil temperature is low, the oil separator efficiency decreases, adversely affecting lubricating oil separation. In this embodiment, by adjusting the opening of the first valve 21 and / or the second valve 22, the amount of oil returning directly from the oil separator 2 to the compressor 1 return port via the first pipeline and the amount of oil returning to the compressor 1 return port after cooling in the oil cooler 6 via the second pipeline can be controlled, thereby ensuring that the return oil temperature equals the preset oil temperature. The first valve 21 and the second valve 22 can be adjustable valves such as electric butterfly valves.

[0056] This embodiment uses liquid drawn from the evaporator as the cold source for the oil cooler, achieving oil cooling through refrigerant self-circulation. Related components and piping can be integrated into the entire unit, facilitating installation and use in engineering projects without requiring additional piping. Furthermore, the refrigerant returns to the evaporator after cooling the lubricating oil, continuing its refrigerant circulation. Oil cooling does not consume heat from the unit, avoiding reduced unit efficiency due to oil cooling. This solves the problem of existing oil cooling methods requiring additional piping or reducing unit efficiency. In addition, the first and second valves ensure that the return oil temperature remains at a suitable level.

[0057] Preferably, the oil cooler 6 can be a shell-and-tube heat exchanger, with lubricating oil as the tube-side medium and refrigerant as the shell-side medium. The refrigerant liquid in the oil cooler 6 is filled to more than 80% of the shell-side volume to ensure the heat exchange effect of the tube side.

[0058] An oil return temperature sensor 23 is installed at the oil return port of compressor 1 to detect the oil return temperature, which serves as the basis for adjusting the oil volume in the first and second pipelines.

[0059] Preferably, the center of gravity of the oil cooler 6 is lower than that of the evaporator 5, the first refrigerant outlet of the evaporator 5 is located at the lowest point of the evaporator 5, and the refrigerant inlet of the oil cooler 6 is located at the lowest point of the oil cooler 6, so that the refrigerant can spontaneously flow and be injected into the oil cooler 6 through the connecting pipe.

[0060] Preferably, the refrigerant outlet of the oil cooler 6 is located at the upper part of the oil cooler 6, and the first refrigerant inlet of the evaporator 5 is located at the upper middle part of the evaporator 5, so that the refrigerant gas in the oil cooler 6 can return to the evaporator 5.

[0061] Considering that conventional compressors cannot operate at low loads—for example, if a compressor has a rated cooling capacity of 1000kW, it must provide at least 250kW of cooling capacity—and cannot continue operating below 25% load, this embodiment provides a solution as follows:

[0062] Evaporator 5 uses a falling film evaporator. For example... Figure 2 As shown, a refrigerant pump 7 and a third valve 8 are connected in parallel on the pipeline between the refrigerant outlet of the oil cooler 6 and the first refrigerant inlet of the evaporator 5. The evaporator 5 also includes a second refrigerant outlet, which is connected to the refrigerant inlet of the condenser 3 via a fourth valve 9. The third valve 8 and the fourth valve 9 can be valves with on / off control functions.

[0063] When the compressor is running normally, the refrigerant pump 7 is turned off, the third valve 8 is opened, and the fourth valve 9 is closed. When the unit's demand load is less than the preset load (e.g., 5%), the compressor 1 is turned off, the refrigerant pump 7 is turned on, the third valve 8 is closed, and the fourth valve 9 is opened. The refrigerant pump 7 provides the power source to draw liquid refrigerant from the oil cooler 6 to the falling film evaporator 5. The liquid refrigerant drips from the top of the evaporator 5 and contacts the heat exchange tubes, where it vaporizes and evaporates for heat exchange. This causes the pressure inside the evaporator 5 to rise. When the pressure inside the evaporator 5 rises, the refrigerant gas automatically enters the condenser 3 through the pipeline where the fourth valve 9 is located. After condensing in the condenser 3, it changes from gas to liquid again to release heat. Then, the liquid refrigerant continues to return to the evaporator 5 through the throttling element 4, continuing the cycle.

[0064] In this embodiment, the compressor 1 can be shut down under low load conditions, and the refrigerant pump 7 provides power for spontaneous refrigerant circulation to provide a certain amount of heat or cooling. The power of the refrigerant pump is much less than that of the compressor, thus achieving energy saving.

[0065] refer to Figure 2The refrigerant connections are as follows: the refrigerant outlet of evaporator 5 is connected to the refrigerant inlet of compressor 1 via pipe A; the refrigerant outlet of compressor 1 is connected to the refrigerant inlet of oil separator 2 via pipe B; the refrigerant outlet of oil separator 2 is connected to the refrigerant inlet of condenser 3 via pipe C; the refrigerant outlet of condenser 3 is connected to the refrigerant inlet of throttling element 4 via pipe D; and the refrigerant outlet of throttling element 4 is connected to the refrigerant inlet of evaporator 5 via pipe E. The refrigerant outlet of evaporator 5 (i.e., the first refrigerant outlet) and the refrigerant inlet of oil cooler 6 are connected via pipe F; the refrigerant outlet of oil cooler 6 is connected to the refrigerant inlet of evaporator 5 (i.e., the second refrigerant inlet) via pipe G. The second refrigerant outlet of evaporator 5 is connected to the refrigerant inlet of condenser 3 via pipe L.

[0066] On the lubricating oil side: the lubricating oil outlet of compressor 1 is connected to the lubricating oil inlet of oil separator 2 via pipe B; the lubricating oil outlet of oil separator 2 is connected to the lubricating oil inlet of oil cooler 6 via pipe H; the lubricating oil outlet of oil cooler 6 is connected to the lubricating oil inlet (i.e., return port) of compressor 1 via pipes I and J; the lubricating oil outlet of oil separator 2 is also connected to the lubricating oil inlet of compressor 1 via pipes K and J.

[0067] Compressor 1 can be a screw compressor, and this embodiment can significantly reduce the oil return temperature of the compressor.

[0068] The working principle is as follows:

[0069] On the refrigerant side: After the refrigerant vaporizes and absorbs heat in the evaporator 5, it becomes superheated vapor and enters the compressor 1 for compression. The compressed refrigerant then enters the oil separator 2 for separation. The separated refrigerant vapor then enters the condenser 3 to release heat to the environment. In the condenser 3, the refrigerant vapor isobarically cooled to the saturation temperature of the current pressure (the current pressure refers to the condensing pressure, which is slightly lower than the discharge pressure), and then continues to cool to the subcooled liquid state. After that, it flows to the throttling element 4 for throttling and cooling (pressure reduction) to a two-phase state, and then enters the evaporator 5 to vaporize and absorb heat, completing one cycle.

[0070] Lubricating oil side: Most of the lubricating oil separated from the refrigerant flows through the lubricating oil outlet of oil separator 2 to pipeline H and pipeline K. The lubricating oil flowing through pipeline H enters oil cooler 6, and after heat exchange and cooling, it enters pipeline I and pipeline J to flow back to compressor 1 for circulation. The lubricating oil flowing through pipeline K directly enters pipeline J to flow back to compressor 1 for circulation.

[0071] Example 2

[0072] This embodiment provides an oil cooling control method applied to the oil cooling system described in the above embodiments. The same or corresponding terminology used in the above embodiments will not be repeated in this embodiment.

[0073] Figure 3 This is a flowchart of the oil cooling control method provided in Embodiment 2 of the present invention, as follows: Figure 3 As shown, the method includes the following steps:

[0074] S301, monitors return oil temperature.

[0075] S302 controls the opening of the first and second valves according to the return oil temperature so that the return oil temperature is equal to the preset oil temperature.

[0076] In this embodiment, the first valve and the second valve can ensure that the return oil temperature is at a suitable oil temperature.

[0077] Specifically, the opening degrees of the first and second valves are controlled based on the return oil temperature, including:

[0078] If the return oil temperature is higher than the preset oil temperature, the opening of the first valve is reduced and / or the opening of the second valve is increased. At this time, the amount of oil flowing through the oil cooler is increased to reduce the return oil temperature to the maximum extent.

[0079] If the return oil temperature is lower than the preset oil temperature, the opening of the first valve is increased and / or the opening of the second valve is decreased. At this time, since the pressure drop of the pipeline where the first valve is located is much smaller than the pressure drop of the pipeline where the second valve is located, most of the lubricating oil is directly bypassed back to the compressor and does not enter the oil cooler for cooling, thereby increasing the return oil temperature.

[0080] If the return oil temperature is equal to the preset oil temperature, the current opening of the first and second valves remains unchanged. The cooled oil and the directly bypassed oil are mixed in proportion and returned to the compressor together, keeping the oil temperature within the normal range.

[0081] The preset oil temperature can be set according to the actual situation of the unit.

[0082] In this embodiment, the return oil temperature is controlled within a reasonable range by adjusting the opening degree of the first valve and the second valve.

[0083] The target opening degree of the first valve can be determined using the following formula:

[0084] Y = Y0 + [(T a -T)+k]×m,

[0085] Where Y represents the target opening degree of the first valve, Y0 represents the initial opening degree of the first valve, and T a The preset oil temperature is represented by T, the current return oil temperature is represented by k, and m is represented by the valve step coefficient.

[0086] The target opening degree of the second valve can be determined using the following formula:

[0087] X = X0 + [(TT) a )+k]×m,

[0088] Where X represents the target opening degree of the second valve, X0 represents the initial opening degree of the second valve, and T a The preset oil temperature is represented by T, the current return oil temperature is represented by k, and m is represented by the valve step coefficient.

[0089] Based on the above formula, the valve opening can be accurately controlled according to the actual situation, and the return oil temperature can be precisely adjusted.

[0090] refer to Figure 4 Here is the control flow diagram for the first and second valves, which includes the following steps:

[0091] S401, detect the return oil temperature T.

[0092] S402, T>Ta, where Ta is the preset oil temperature.

[0093] S403, the first valve is closed slightly, and the second valve is opened fully.

[0094] S404, T≈Ta.

[0095] S405, the first and second valves remain at their current opening degrees.

[0096] S406, T < Ta.

[0097] S407, the first valve is opened wide, and the second valve is closed slightly.

[0098] Considering that conventional compressors cannot operate at low loads, in one embodiment, the following controls are provided:

[0099] When the compressor is running normally, turn off the refrigerant pump, open the third valve, and close the fourth valve;

[0100] When the unit's demand load is less than the preset load, the compressor is turned off, the refrigerant pump is turned on, the third valve is closed, the fourth valve is opened, and the opening degree of the throttling element between the evaporator and the condenser is controlled so that the pressure difference between the evaporator and the condenser is within the preset range.

[0101] The preset load can be set according to the actual situation of the unit, for example, set to 5%. The preset range can also be set according to the actual situation of the unit to ensure that the refrigerant circulates spontaneously between the oil cooler, evaporator, condenser, and throttling element when the compressor is off, thus meeting user needs.

[0102] This embodiment can shut down the compressor under low-load conditions and use the refrigerant pump to power the spontaneous circulation of refrigerant to provide a certain amount of heat or cooling. The power of the refrigerant pump is much less than that of the compressor, achieving energy-saving effects. Furthermore, by adjusting the throttling element, the evaporator pressure can be made greater than the condenser pressure, and the pressure difference between the evaporator and condenser can be kept within a preset range, ensuring a certain pressure difference to promote spontaneous refrigerant circulation.

[0103] When the compressor is shut down, there is no power source to generate a pressure difference in the refrigeration system. At this time, the refrigerant pump draws the liquid refrigerant from the oil cooler to the evaporator, where it exchanges heat through the heat exchange tubes. Due to the temperature difference between the heat exchange tubes and the liquid refrigerant in the oil cooler, a phase change heat transfer occurs when the liquid refrigerant is sprayed onto the heat exchange tubes, changing from liquid to gas. During this process, the liquid refrigerant absorbs a large amount of heat, simultaneously increasing the pressure inside the evaporator. Once the evaporator pressure rises, the refrigerant gas spontaneously enters the condenser through the pipe containing the fourth valve. Inside the condenser, it re-liquefies upon contact with the heat exchange tubes, releasing a large amount of heat. The liquid refrigerant then returns to the evaporator through the throttling element, continuing the cycle. As the amount of liquid refrigerant in the condenser increases, the pressure between the two units can be adjusted using the throttling element to maintain the pressure difference between the evaporator and condenser within a preset range, thus sustaining system operation under these conditions.

[0104] Example 3

[0105] This embodiment provides a non-volatile computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the oil cooling control method described in the above embodiment.

[0106] Example 4

[0107] This embodiment provides an electronic device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the oil cooling control method described in the above embodiment.

[0108] Figure 5 This is a schematic diagram of the hardware structure of the electronic device provided in Embodiment 4 of the present invention, as shown below. Figure 5 As shown, the electronic device includes:

[0109] One or more processors 510 and memory 520, Figure 5 Take the 510 processor as an example.

[0110] The electronic device may also include: an input device 530 and an output device 540.

[0111] The processor 510, memory 520, input device 530, and output device 540 can be connected via a bus or other means. Figure 5 Taking the example of a connection between China and Israel via a bus.

[0112] The memory 520, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the oil cooling control method in this embodiment of the invention. The processor 510 executes various functional applications and data processing by running the non-volatile software programs, instructions, and modules stored in the memory 520, thereby implementing the aforementioned oil cooling control method.

[0113] The memory 520 may include a program storage area and a data storage area. The program storage area may store the application program required for operating the device and at least one function. The data storage area may store preset oil temperature, opening degree calculation formulas, etc. In addition, the memory 520 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device.

[0114] Input device 530 can receive input digital or character information, and generate key signal inputs related to user settings and function control of the electronic device. Output device 540 may include display devices such as a display screen.

[0115] The one or more modules are stored in the memory 520, and when executed by the one or more processors 510, they execute the oil cooling control method in any of the above method embodiments.

[0116] The device embodiments described above are merely illustrative. 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 modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0117] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, 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 can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An oil cooling system, characterized in that, include: Compressor, oil separator, oil cooler, and evaporator; The oil outlet of the oil separator is connected to the oil return port of the compressor through a first pipeline and a second pipeline connected in parallel. A first valve is installed on the first pipeline; The second pipeline passes through the oil cooler, and a second valve is installed in the second pipeline between the oil outlet of the oil separator and the oil inlet of the oil cooler; The first refrigerant outlet of the evaporator is connected to the refrigerant inlet of the oil cooler, and the first refrigerant inlet of the evaporator is connected to the refrigerant outlet of the oil cooler. The evaporator also includes a second refrigerant outlet, which is connected to the refrigerant inlet of the condenser via a fourth valve. The center of gravity of the oil cooler is lower than that of the evaporator; the first refrigerant outlet of the evaporator is located at the lowest point of the evaporator; the refrigerant outlet of the oil cooler is located at the upper part of the oil cooler, and the refrigerant is spontaneously injected and immersed into the oil cooler through the connecting pipeline.

2. The oil cooling system according to claim 1, characterized in that, An oil return temperature sensor is installed at the oil return port of the compressor.

3. The oil cooling system according to claim 1, characterized in that, The evaporator is a falling film evaporator.

4. The oil cooling system according to claim 3, characterized in that, A refrigerant pump and a third valve are connected in parallel on the pipeline between the refrigerant outlet of the oil cooler and the first refrigerant inlet of the evaporator.

5. An oil cooling control method, characterized in that, The method, applied to the oil cooling system of any one of claims 1 to 4, comprises: Monitor return oil temperature; The opening degree of the first valve and the second valve is controlled according to the oil return temperature so that the oil return temperature is equal to the preset oil temperature.

6. The method according to claim 5, characterized in that, Controlling the opening degree of the first valve and the second valve according to the return oil temperature includes: If the return oil temperature is greater than the preset oil temperature, then reduce the opening of the first valve and / or increase the opening of the second valve; If the return oil temperature is lower than the preset oil temperature, then increase the opening of the first valve and / or decrease the opening of the second valve; If the return oil temperature is equal to the preset oil temperature, then the current opening degree of the first valve and the second valve remains unchanged.

7. The method according to claim 6, characterized in that, The target opening degree of the first valve shall be determined according to the following formula: Y=Y0+[(T a -T)+k]×m, Where Y represents the target opening degree of the first valve, Y0 represents the initial opening degree of the first valve, and T a The preset oil temperature is represented by T, the current return oil temperature is represented by k, and m is represented by the valve step coefficient.

8. The method according to claim 6, characterized in that, The target opening degree of the second valve shall be determined according to the following formula: X=X0+[(T-T a )+k]×m, Where X represents the target opening degree of the second valve, X0 represents the initial opening degree of the second valve, and T a The preset oil temperature is represented by T, the current return oil temperature is represented by k, and m is represented by the valve step coefficient.

9. The method according to any one of claims 5 to 8, characterized in that, Also includes: When the compressor is running normally, turn off the refrigerant pump, open the third valve, and close the fourth valve; When the unit's demand load is less than the preset load, the compressor is turned off, the refrigerant pump is turned on, the third valve is closed, the fourth valve is opened, and the opening degree of the throttling element between the evaporator and the condenser is controlled so that the pressure difference between the evaporator and the condenser is within the preset range.

10. A non-volatile computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 5 to 9.

Images