Liquid supply method for a refrigeration system and its hydrostatic bearing

Abstract

The present invention relates to a refrigeration system and a liquid supply method for a hydrostatic bearing thereof. Among them, the refrigeration system includes: a refrigeration cycle circuit, the refrigeration cycle circuit includes a compressor, the compressor includes a hydrostatic bearing and a rotating shaft, the hydrostatic bearing supports the rotating shaft, and a plurality of micropores are provided on the outer periphery of the hydrostatic bearing; and a liquid supply assembly, which communicates with the liquid storage part of the refrigeration cycle circuit and the hydrostatic bearing, the liquid storage part has liquid refrigerant, the liquid supply assembly is configured to direct the liquid refrigerant in the liquid storage part to the hydrostatic bearing, and make the liquid refrigerant enter between the hydrostatic bearing and the rotating shaft through the micropores. The present invention uses liquid refrigerant as the lubricant between the hydrostatic bearing and the rotating shaft, improves the load-bearing capacity and impact resistance of the hydrostatic bearing, and using liquid refrigerant as the lubricant will not mix other impurities except refrigerant into the refrigeration cycle circuit, thereby improving the performance of the compressor.

Description

Technical Field

[0001] The present invention relates to the field of fluid machinery, and particularly to a refrigeration system and a liquid supply method for a static pressure bearing thereof. Background Art

[0002] Centrifugal chillers are usually used in various building air conditionings. A centrifugal chiller includes a centrifugal compressor. A bearing is a basic part that supports the shaft of the centrifugal compressor and the parts on the shaft to perform mechanical rotation. According to different bearing lubrication forms, there are usually two types: oil-lubricated bearings and oil-free lubricated bearings.

[0003] Oil-lubricated bearings have the characteristics of large load-carrying capacity and strong anti-vibration ability, but they require an additional lubricating oil supply system, which increases the system complexity. Moreover, the lubricating oil will leak into the refrigeration system during the operation of the compressor and mix with the refrigerant. Therefore, it is necessary to set up a lubricating oil return system for periodic oil return.

[0004] Common oil-free lubricated bearings include air suspension bearings. An air suspension bearing uses gas as a lubricant and utilizes the characteristics of gas such as adsorption, transmission (diffusion, viscosity, and heat conduction), and compressibility. During friction, under the action of hydrodynamic pressure effect, static pressure effect, and squeeze effect, a gas film is formed to support the load and reduce friction. However, due to the characteristics of gas such as compressibility and low viscosity, the load-carrying capacity of the bearing has a certain upper limit, and the anti-impact ability is limited. Summary of the Invention

[0005] Some embodiments of the present invention provide a refrigeration system and a liquid supply method for a static pressure bearing thereof, which are used to alleviate the problem of insufficient bearing capacity.

[0006] In one aspect of the present invention, a refrigeration system is provided, including:

[0007] A refrigeration cycle circuit, the refrigeration cycle circuit includes a compressor, the compressor includes a static pressure bearing and a rotating shaft, the static pressure bearing supports the rotating shaft, and a plurality of micropores are provided on the outer periphery of the static pressure bearing; and

[0008] A liquid supply assembly, which communicates with the liquid storage part of the refrigeration cycle circuit and the static pressure bearing. The liquid storage part has liquid refrigerant, and the liquid supply assembly is configured to direct the liquid refrigerant in the liquid storage part to the static pressure bearing and make the liquid refrigerant enter between the static pressure bearing and the rotating shaft through the micropores.

[0009] In some embodiments, the refrigeration cycle circuit further includes an evaporator, the liquid storage part includes the bottom of the evaporator, the liquid supply assembly includes a first pipeline, the input end of the first pipeline is communicated with the bottom of the evaporator, and the output end of the first pipeline is communicated with the static pressure bearing.

[0010] In some embodiments, the liquid supply assembly further includes a first pump, and the first pump is disposed on the first pipeline.

[0011] In some embodiments, the liquid supply assembly further includes a first regulating valve, the first regulating valve is disposed on the first pipeline, and the first regulating valve is configured to regulate the on / off and flow area of the first pipeline.

[0012] In some embodiments, the refrigeration cycle loop further includes a condenser, the liquid storage part includes the bottom of the condenser, the liquid supply assembly further includes a second pipeline, an input end of the second pipeline is communicated with the bottom of the condenser, and an output end of the second pipeline is communicated with the hydrostatic bearing.

[0013] In some embodiments, the liquid supply assembly further includes a second regulating valve, the second regulating valve is disposed on the second pipeline, and the second regulating valve is configured to regulate the on / off and flow area of the second pipeline.

[0014] In some embodiments, the liquid supply assembly further includes a third pipeline, and output ends of both the first pipeline and the second pipeline are communicated with the hydrostatic bearing through the third pipeline.

[0015] In some embodiments, the liquid supply assembly further includes a fourth pipeline and a third regulating valve, an input end of the fourth pipeline is communicated with the third pipeline, an output end of the fourth pipeline is communicated with the evaporator, the third regulating valve is disposed on the fourth pipeline, and the third regulating valve is configured to regulate the on / off and flow area of the fourth pipeline.

[0016] In some embodiments, the liquid supply assembly further includes a fourth pipeline and a third regulating valve, an input end of the fourth pipeline is communicated with an output end of the first pipeline, an output end of the fourth pipeline is communicated with the evaporator, the third regulating valve is disposed on the fourth pipeline, and the third regulating valve is configured to regulate the on / off and flow area of the fourth pipeline.

[0017] In some embodiments, the liquid supply assembly further includes a fourth pipeline and a third regulating valve, an input end of the fourth pipeline is communicated with an output end of the second pipeline, an output end of the fourth pipeline is communicated with the evaporator, the third regulating valve is disposed on the fourth pipeline, and the third regulating valve is configured to regulate the on / off and flow area of the fourth pipeline.

[0018] In some embodiments, the refrigeration cycle loop further includes a flash tank, the liquid storage part includes the bottom of the flash tank, the liquid supply assembly includes a fifth pipeline, an input end of the fifth pipeline is communicated with the bottom of the flash tank, and an output end of the fifth pipeline is communicated with the hydrostatic bearing.

[0019] In some embodiments, the liquid supply assembly further includes a second pump, and the second pump is disposed on the fifth pipeline.

[0020] In some embodiments, the liquid supply assembly further includes a fourth regulating valve, and the fourth regulating valve is disposed on the fifth pipeline. The fourth regulating valve is configured to regulate the on / off state and the flow area of the fifth pipeline.

[0021] In some embodiments, the refrigeration cycle loop further includes a condenser. The liquid storage part includes the bottom of the condenser. The liquid supply assembly further includes a second pipeline. The input end of the second pipeline is communicated with the bottom of the condenser, and the output end of the second pipeline is communicated with the hydrostatic bearing.

[0022] In some embodiments, the diameter range of the micropores is 0.01 mm to 0.2 mm.

[0023] In one aspect of the present invention, a liquid supply method for a hydrostatic bearing of a refrigeration system is provided, including:

[0024] Providing a refrigeration cycle loop, the refrigeration cycle loop includes a compressor, the compressor includes a hydrostatic bearing and a rotating shaft, the hydrostatic bearing supports the rotating shaft, and a plurality of micropores are provided on the outer periphery of the hydrostatic bearing; and

[0025] Providing a liquid supply assembly, guiding the liquid refrigerant in the liquid storage part of the refrigeration cycle loop to the hydrostatic bearing through the liquid supply assembly, and enabling the liquid refrigerant to enter between the hydrostatic bearing and the rotating shaft through the micropores on the hydrostatic bearing.

[0026] In some embodiments, the refrigeration cycle loop further includes an evaporator. The liquid storage part includes the bottom of the evaporator. The liquid supply assembly includes a first pipeline, a first pump, and a first regulating valve. The input end of the first pipeline is communicated with the bottom of the evaporator, the output end of the first pipeline is communicated with the hydrostatic bearing, and the first pump and the first regulating valve are disposed on the first pipeline;

[0027] The step of guiding the liquid refrigerant in the liquid storage part of the refrigeration cycle loop to the hydrostatic bearing through the liquid supply assembly includes:

[0028] During the startup, shutdown, or low-speed operation stage of the compressor, the first pump and the first regulating valve are opened. Under the action of the first pump, the liquid refrigerant at the bottom of the evaporator flows to the hydrostatic bearing and enters between the hydrostatic bearing and the rotating shaft through the micropores on the hydrostatic bearing. Meanwhile, the flow area of the first pipeline is adjusted through the first regulating valve, and further the pressure of the liquid refrigerant entering between the hydrostatic bearing and the rotating shaft is adjusted.

[0029] In some embodiments, the refrigeration cycle loop further includes a condenser, the liquid storage part includes the bottom of the condenser, the liquid supply assembly further includes a second pipeline and a second regulating valve, the input end of the second pipeline is communicated with the bottom of the condenser, the output end of the second pipeline is communicated with the hydrostatic bearing, and the second regulating valve is arranged on the second pipeline;

[0030] The step of guiding the liquid refrigerant in the liquid storage part of the refrigeration cycle loop to the hydrostatic bearing through the liquid supply assembly further includes:

[0031] After the compressor operates at high speed to establish a pressure difference, open the second regulating valve, gradually close the first pump and the first regulating valve, the pressure in the condenser causes the liquid refrigerant at the bottom of the condenser to flow to the hydrostatic bearing, and enter between the hydrostatic bearing and the rotating shaft through the micropores on the hydrostatic bearing; meanwhile, adjust the flow area of the second pipeline through the second regulating valve, and further adjust the pressure of the liquid refrigerant entering between the hydrostatic bearing and the shaft.

[0032] In some embodiments, the liquid supply assembly includes a third pipeline, a fourth pipeline and a third regulating valve, the output ends of the first pipeline and the second pipeline are both communicated with the hydrostatic bearing through the third pipeline; the input end of the fourth pipeline is communicated with the third pipeline, the output end of the fourth pipeline is communicated with the evaporator, and the third regulating valve is arranged on the fourth pipeline;

[0033] During the startup, shutdown or low-speed operation stage of the compressor, if the pressure of the liquid refrigerant flowing from the first pipeline between the hydrostatic bearing and the rotating shaft is greater than the preset pressure value, open the third regulating valve, and cooperate with the first regulating valve through the third regulating valve to adjust the pressure of the liquid refrigerant flowing between the hydrostatic bearing and the shaft.

[0034] In some embodiments, the liquid supply assembly includes a third pipeline, a fourth pipeline and a third regulating valve, the output ends of the first pipeline and the second pipeline are both communicated with the hydrostatic bearing through the third pipeline; the input end of the fourth pipeline is communicated with the third pipeline, the output end of the fourth pipeline is communicated with the evaporator, and the third regulating valve is arranged on the fourth pipeline;

[0035] After the compressor operates at high speed to establish a pressure difference, when the first pump and the first regulating valve are in the closed state, if the pressure of the liquid refrigerant flowing from the second pipeline between the hydrostatic bearing and the rotating shaft is greater than the preset pressure value, open the third regulating valve, and cooperate with the second regulating valve through the third regulating valve to adjust the pressure of the liquid refrigerant flowing between the hydrostatic bearing and the rotating shaft.

[0036] Based on the above technical solutions, the present invention has at least the following beneficial effects:

[0037] In some embodiments, liquid refrigerant is led out from the liquid storage part in the refrigeration cycle loop and directed to the hydrostatic bearing in the compressor in the refrigeration cycle loop. The liquid refrigerant is used as the lubricant between the hydrostatic bearing and the rotating shaft, which improves the load-bearing capacity and impact resistance of the hydrostatic bearing. Moreover, using the liquid refrigerant as the lubricant will not cause other impurities other than the refrigerant to mix into the refrigeration cycle loop, thereby improving the performance of the compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0039] Figure 1 is a schematic diagram of a refrigeration system according to some embodiments of the present invention;

[0040] Figure 2 is a schematic diagram of a refrigeration system according to some other embodiments of the present invention;

[0041] Figure 3 is a schematic diagram of a hydrostatic bearing according to some embodiments of the present invention;

[0042] Figure 4 is a schematic diagram of the cooperation of a hydrostatic bearing, a rotating shaft and a bearing housing according to some embodiments of the present invention;

[0043] Figure 5 is Figure 4 an enlarged schematic diagram of the partial structure A in

[0044] The reference numerals in the drawings are explained as follows:

[0045] 1 - refrigeration cycle loop; 11 - compressor; 12 - evaporator; 13 - condenser; 14 - flash tank; 15 - hydrostatic bearing; 151 - micropore; 152 - main body part; 153 - end part; 154 - groove; 16 - rotating shaft; 17 - bearing housing; 171 - liquid inlet hole; 18 - liquid storage cavity; 19 - sealing ring; 110 - gap; 111 - first throttle valve; 112 - second throttle valve;

[0046] 2 - liquid supply assembly;

[0047] 211 - first pipeline; 212 - first pump; 213 - first regulating valve; 214 - first check valve; 215 - first filter;

[0048] 221 - second pipeline; 222 - second regulating valve; 223 - second check valve; 224 - second filter;

[0049] 231 - Third pipeline; 232 - Third one - way valve; 233 - Fourth sensor;

[0050] 241 - Fourth pipeline; 242 - Third regulating valve;

[0051] 251 - Fifth pipeline; 252 - Second pump; 253 - Fourth regulating valve; 254 - Fourth one - way valve; 255 - Third filter;

[0052] 271 - First pressure sensor; 272 - Second pressure sensor; 273 - Third pressure sensor.

[0053] It should be understood that the dimensions of the various parts shown in the drawings are not drawn according to the actual proportional relationship. In addition, the same or similar reference numerals represent the same or similar components. Detailed implementation manners

[0054] Now, various exemplary embodiments of the present invention will be described in detail with reference to the drawings. The description of the exemplary embodiments is merely illustrative and in no way limits the present invention and its application or use. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided to make the present invention thorough and complete and to fully convey the scope of the present invention to those skilled in the art. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, the compositions of materials, numerical expressions and values set forth in these embodiments should be construed as merely exemplary and not as limitations.

[0055] The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different parts. Terms such as "comprising" or "including" mean that the elements before this term cover the elements listed after this term, and do not exclude the possibility of also covering other elements. Terms such as "upper", "lower", "left", "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0056] In the present invention, when it is described that a specific device is located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When it is described that a specific device is connected to other devices, the specific device may be directly connected to the other devices without an intermediate device, or may not be directly connected to the other devices and have an intermediate device.

[0057] All terms used in the present invention (including technical or scientific terms) have the same meaning as understood by those of ordinary skill in the art to which the present invention pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense, unless specifically defined as such herein.

[0058] Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such technologies, methods, and devices should be regarded as part of the specification.

[0059] As Figure 1 shown, some embodiments provide a refrigeration system, which includes a refrigeration cycle circuit 1 and a liquid supply assembly 2.

[0060] The refrigeration cycle circuit 1 includes a compressor 11. The compressor 11 includes a hydrostatic bearing 15 and a rotating shaft 16. The hydrostatic bearing 15 supports the rotating shaft 16, and a plurality of micropores 151 are provided on the outer periphery of the hydrostatic bearing 15.

[0061] The liquid supply assembly 2 communicates with the liquid storage part of the refrigeration cycle circuit 1 and the hydrostatic bearing 15. The liquid storage part has liquid refrigerant. The liquid supply assembly 2 is configured to direct the liquid refrigerant in the liquid storage part to the hydrostatic bearing 15, and enable the liquid refrigerant to enter between the hydrostatic bearing 15 and the rotating shaft 16 through the micropores 151.

[0062] In the above embodiment, liquid refrigerant is used as the lubricant between the hydrostatic bearing and the rotating shaft, which improves the load-bearing capacity and impact resistance of the hydrostatic bearing. Moreover, as the lubricant, the liquid refrigerant will not cause other impurities except refrigerant to mix into the refrigeration cycle circuit, such as lubricating oil, etc., thus improving the performance of the compressor.

[0063] As Figure 3 shown, in some embodiments, the hydrostatic bearing 15 includes a hollow, annular main body part 152. The micropores 151 are provided on the main body part 152. Annular end parts 153 are respectively provided at both axial ends of the main body part 152. The radial dimension of the end part 153 is larger than the radial dimension of the main body part 152. The main body part 152 is provided with a groove 154 for accommodating a sealing ring 19.

[0064] A plurality of rows of micropores 151 are circumferentially spaced on the main body part 152. Each micropore 151 in each row of micropores 151 is arranged in sequence along the axial direction of the hydrostatic bearing 15. The specific number of the micropores 151 is mainly determined by the designed bearing capacity F of the hydrostatic bearing and the aperture D of the micropores 151. Among them, the smaller the aperture D of the micropores 151 and the more the number of micropores, the larger the designed bearing capacity F.

[0065] As Figure 4As shown, the compressor 11 further includes a bearing housing 17 and a sealing ring 19. The hydrostatic bearing 15 is disposed in the bearing housing 17, and the rotating shaft 16 is inserted into the hydrostatic bearing 15, and the hydrostatic bearing 15 supports the rotating shaft 16. Since the hydrostatic bearing 15 includes a main body portion 152 and an end portion 153, the radial dimension of the main body portion 152 is smaller than the radial dimension of the end portion 153, and a liquid storage cavity 18 is formed between the main body portion 152 and the bearing housing 17, and the bearing housing 17 is provided with a liquid inlet hole 171 communicating with the liquid storage cavity 18. The liquid refrigerant introduced by the liquid supply assembly 2 from the liquid storage part of the refrigeration cycle circuit 1 enters the liquid storage cavity 18 through the liquid inlet hole 171, and then enters the gap 110 between the hydrostatic bearing 15 and the rotating shaft 16 through the liquid storage cavity 18 and the micropores 151 on the hydrostatic bearing 15, as Figure 5 shown. During operation, the motor shaft rotates at a high speed under the action of the electromagnetic field. The liquid refrigerant flowing into the gap 110 through the micropores 151 of the hydrostatic bearing 15 suspends and supports the rotating shaft 16 after throttling through the micropores 151.

[0066] The liquid refrigerant in the liquid storage cavity 18 enters the gap 110 between the hydrostatic bearing 15 and the rotating shaft 16 through the micropores 151 on the hydrostatic bearing 15. Since the diameter of the micropores 151 is very small (0.01 - 0.20 mm), the liquid refrigerant undergoes throttling in the micropores 151, so that the flow rate and pressure of the liquid refrigerant are increased, forming a high-pressure liquid refrigerant after throttling, and filling the gap 110 between the hydrostatic bearing 15 and the rotating shaft 16, thereby effectively supporting the rotating shaft 16.

[0067] In the embodiment of the present disclosure, the liquid refrigerant is used as the lubricant between the hydrostatic bearing 15 and the rotating shaft 16. Compared with the gaseous refrigerant, the liquid refrigerant has a greater viscosity, so that the stiffness and damping of the hydrostatic bearing 15 are greater. At the same time, the liquid refrigerant is difficult to compress, so when the rotating shaft 16 vibrates (such as when the rotational speed is increased, decreased, or the working condition is switched), the liquid refrigerant filling the gap between the hydrostatic bearing 15 and the rotating shaft 16 also plays a good anti-impact role.

[0068] The hydrostatic bearing 15 includes a gas micropore hydrostatic bearing, and the liquid refrigerant is used as the lubricant to suspend the gas micropore hydrostatic bearing. Using the liquid refrigerant as the lubricant for the gas micropore hydrostatic bearing has better effects than using the gaseous refrigerant. This is because the liquid has a higher viscosity and lower compressibility than the gas, so the liquid lubricant can bring greater load-bearing capacity and anti-impact ability to the gas micropore hydrostatic bearing.

[0069] In some embodiments, both the hydrostatic bearing 15 and the bearing housing 17 are made of metal materials.

[0070] In some embodiments, the bearing housing 17 is a hollow annular part, which plays a role in fixing and supporting the hydrostatic bearing 15.

[0071] In some embodiments, the liquid storage chamber 18 is formed by the main body portion 152 of the hydrostatic bearing 15 and the inner hole of the bearing housing 17, and is used to store the liquid refrigerant and buffer it.

[0072] In some embodiments, grooves 154 are provided at both ends 153 of the hydrostatic bearing 15, and sealing rings 19 are provided in the grooves 154. The sealing rings 19 are fixed in the inner hole of the bearing housing 17. The main functions of the sealing rings 19 are: to provide damping for the hydrostatic bearing 15, to seal both ends of the hydrostatic bearing 15, and to prevent the liquid in the liquid storage chamber 18 from leaking.

[0073] In some embodiments, the rotating shaft 16 includes a motor shaft, which is an important part of the centrifugal compressor rotor and is a shaft-like solid part.

[0074] In some embodiments, the refrigeration cycle loop 1 further includes a first pressure sensor 271, which is arranged on the compressor 11 and is used to detect the ambient pressure of the hydrostatic bearing in the compressor 11.

[0075] In some embodiments, the refrigeration cycle loop 1 further includes an evaporator 12. The liquid storage part includes the bottom of the evaporator 12. The liquid supply assembly 2 includes a first pipeline 211. The input end of the first pipeline 211 is communicated with the bottom of the evaporator 12, and the output end of the first pipeline 211 is communicated with the hydrostatic bearing 15.

[0076] The bottom of the evaporator 12 refers to the bottom of the part in the evaporator 12 where the liquid refrigerant remains.

[0077] According to the working principle of the refrigeration centrifugal unit, during operation, the pressure of the evaporator 12 is the lowest. Therefore, under the action of the system pressure difference, the most liquid refrigerant remains inside the evaporator 12, and even in the case of shutdown, the most liquid refrigerant remains. Therefore, liquid can be preferentially taken from the bottom of the evaporator 12 during stages such as startup, shutdown, or low-speed operation of the unit.

[0078] During stages such as startup, shutdown, or low-speed operation of the unit, liquid refrigerant in the atmospheric pressure state is preferentially taken from the evaporator 12 to achieve continuous and stable liquid supply to the hydrostatic bearing 15 in the compressor 11. Since the liquid refrigerant has greater viscosity and incompressibility compared to the gaseous refrigerant, using the liquid refrigerant as the working medium for the hydrostatic bearing 15 has greater load-bearing capacity and anti-impact ability.

[0079] In some embodiments, the liquid supply assembly 2 further includes a second pressure sensor 272, which is arranged on the evaporator 12 and is used to detect the pressure inside the evaporator 12.

[0080] In some embodiments, the liquid supply assembly 2 further includes a first pump 212, and the first pump 212 is arranged on the first pipeline 211. By providing power through the first pump 212, the liquid refrigerant remaining in the evaporator 12 is pumped towards the hydrostatic bearing 15.

[0081] In some embodiments, the liquid supply assembly 2 further includes a first regulating valve 213. The first regulating valve 213 is arranged on the first pipeline 211, and the first regulating valve 213 is configured to regulate the on-off and flow area of the first pipeline 211.

[0082] When the first regulating valve 213 is fully closed, the first pipeline 211 is disconnected. By increasing the opening degree of the first regulating valve 213, the pressure of the liquid refrigerant flowing towards the hydrostatic bearing 15 increases, and the liquid flow rate entering the hydrostatic bearing 15 increases; conversely, by decreasing the opening degree of the first regulating valve 213, the pressure of the liquid refrigerant flowing towards the hydrostatic bearing 15 decreases, and the liquid flow rate entering the hydrostatic bearing 15 decreases.

[0083] The regulation basis for the opening degree of the first regulating valve 213 is: by regulating the opening degree of the first regulating valve 213, after subtracting the ambient pressure of the hydrostatic bearing 15 inside the compressor 11 from the pressure of the liquid refrigerant flowing towards the hydrostatic bearing 15, it can still meet the bearing capacity required to support the rotating shaft 16.

[0084] That is: △P = P1 - P0, where △P is the supply pressure difference, and the purpose is to make △P equal to the bearing capacity required to support the rotating shaft 16, P1 is the pressure of the liquid refrigerant provided by the liquid supply assembly 2 to the hydrostatic bearing 15, and P0 is the ambient pressure of the hydrostatic bearing 15 inside the compressor 11.

[0085] By jointly controlling the first pump 212 and the first regulating valve 213, △P reaches a preset pressure value, and the preset pressure value is equal to the bearing capacity required to support the rotating shaft 16.

[0086] In some embodiments, the liquid supply assembly 2 further includes a first check valve 214, and the first check valve 214 is arranged on the first pipeline 211. The inlet of the first check valve 214 is communicated with the evaporator 12, and the outlet of the first check valve 214 is communicated with the hydrostatic bearing 15. The first check valve 214 is used to prevent the liquid refrigerant in the hydrostatic bearing 15 from flowing back into the evaporator 12.

[0087] In some embodiments, the liquid supply assembly 2 further includes a first filter 215, and the first filter 215 is arranged on the first pipeline 211. The first filter 215 is used to filter the liquid refrigerant flowing from the first pipeline 211 towards the hydrostatic bearing 15, and prevent impurities in the liquid refrigerant from clogging the micropores 151 on the hydrostatic bearing 15.

[0088] In some embodiments, the refrigeration cycle loop 1 further includes a condenser 13. The liquid storage part includes the bottom of the condenser 13. The liquid supply assembly 2 further includes a second pipeline 221. The input end of the second pipeline 221 communicates with the bottom of the condenser 13, and the output end of the second pipeline 221 communicates with the static pressure bearing 15.

[0089] The bottom of the condenser 13 is the bottom of the part where the liquid refrigerant remains in the condenser 13.

[0090] After the pressure difference is established when the unit operates at high speed, the pressure in the condenser 13 is the highest. The high-pressure liquid refrigerant is preferentially taken from the condenser 13 to continuously and stably supply liquid to the static pressure bearing 15 in the compressor 11.

[0091] In some embodiments, the liquid supply assembly 2 further includes a third pressure sensor 273. The third pressure sensor 273 is arranged on the condenser 13 and is used to detect the pressure in the condenser 13.

[0092] In some embodiments, the liquid supply assembly 2 further includes a second regulating valve 222. The second regulating valve 222 is arranged on the second pipeline 221, and the second regulating valve 222 is configured to regulate the on-off and flow area of the second pipeline 221.

[0093] When the second regulating valve 222 is closed, the second pipeline 221 is disconnected. By increasing the opening degree of the second regulating valve 222, the pressure of the liquid refrigerant flowing to the static pressure bearing 15 increases, and the liquid flow rate entering the static pressure bearing 15 increases; conversely, by decreasing the opening degree of the second regulating valve 222, the pressure of the liquid refrigerant flowing to the static pressure bearing 15 decreases, and the liquid flow rate entering the static pressure bearing 15 decreases.

[0094] The regulation basis for the opening degree of the second regulating valve 222 is: by regulating the opening degree of the second regulating valve 222, after the pressure of the liquid refrigerant flowing to the static pressure bearing 15 minus the ambient pressure of the static pressure bearing 15 inside the compressor 11, it can still meet the bearing capacity required to support the rotating shaft 16.

[0095] That is to say, whether taking the liquid refrigerant from the evaporator 12 or from the condenser 13, it is: △P = P1 - P0, where △P is the liquid supply pressure difference, and the purpose is to make △P equal to the bearing capacity required to support the rotating shaft 16, P1 is the pressure of the liquid refrigerant provided by the liquid supply assembly 2 to the static pressure bearing 15, and P0 is the ambient pressure of the static pressure bearing 15 inside the compressor 11.

[0096] In some embodiments, the liquid supply assembly 2 further includes a second one-way valve 223. The second one-way valve 223 is provided in the second pipeline 221. The inlet of the second one-way valve 223 is communicated with the condenser 273, and the outlet of the second one-way valve 223 is communicated with the hydrostatic bearing 15. The second one-way valve 223 is used to prevent the liquid refrigerant in the hydrostatic bearing 15 from flowing back to the condenser 273.

[0097] In some embodiments, the liquid supply assembly 2 further includes a second filter 224. The second filter 224 is provided in the second pipeline 221. The second filter 224 is used to filter the liquid refrigerant flowing from the second pipeline 221 to the hydrostatic bearing 15, and prevent impurities in the liquid refrigerant from clogging the micropores 151 on the hydrostatic bearing 15.

[0098] In some embodiments, the liquid supply assembly 2 includes a third pipeline 231. The output ends of the first pipeline 211 and the second pipeline 221 are both communicated with the hydrostatic bearing 15 through the third pipeline 231.

[0099] Of course, the first pipeline 211 and the second pipeline 221 may also be respectively communicated with the hydrostatic bearing 15. By providing the third pipeline 231, the output ends of the first pipeline 211 and the second pipeline 221 are both communicated with the hydrostatic bearing 15 through the third pipeline 231, which can simplify the connection structure of the hydrostatic bearing 15.

[0100] In some embodiments, the liquid supply assembly 2 includes a third one-way valve 232. The third one-way valve 232 is provided in the third pipeline 231. The inlet of the third one-way valve 232 is communicated with the first pipeline 211 and the second pipeline 221, and the outlet of the third one-way valve 232 is communicated with the hydrostatic bearing 15. The third one-way valve 232 is used to prevent the liquid refrigerant in the hydrostatic bearing 15 from flowing back to the first pipeline 211 and the second pipeline 221.

[0101] In some embodiments, the liquid supply assembly 2 includes a fourth pressure sensor 233. The fourth pressure sensor 233 is provided in the third pipeline 231 and is used to detect the pressure in the third pipeline 231.

[0102] In some embodiments, the liquid supply assembly 2 further includes a fourth pipeline 241 and a third regulating valve 242. The input end of the fourth pipeline 241 is communicated with the third pipeline 231, and the output end of the fourth pipeline 241 is communicated with the evaporator 12. The third regulating valve 242 is provided in the fourth pipeline 241, and the third regulating valve 242 is configured to regulate the on-off and flow area of the fourth pipeline 241. And due to the third one-way valve 232 provided on the third pipeline 231, by providing the third one-way valve 232, it is possible to prevent the liquid refrigerant in the hydrostatic bearing 15 from flowing back to the fourth pipeline 241 through the third pipeline 231.

[0103] Of course, the output end of the first pipeline 211 and the output end of the second pipeline 221 can be respectively communicated with the fourth pipeline 241. In the above embodiment, the third pipeline 231 is communicated with the fourth pipeline 241, which can simplify the pipeline connection structure.

[0104] For example: the input end of the fourth pipeline 241 is communicated with the output end of the first pipeline 211, the output end of the fourth pipeline 241 is communicated with the evaporator 12, a third regulating valve 242 is arranged on the fourth pipeline 241, and the third regulating valve 242 is configured to regulate the on-off and flow area of the fourth pipeline 241.

[0105] The input end of the fourth pipeline 241 is communicated with the output end of the second pipeline 221, the output end of the fourth pipeline 241 is communicated with the evaporator 12, a third regulating valve 242 is arranged on the fourth pipeline 241, and the third regulating valve 242 is configured to regulate the on-off and flow area of the fourth pipeline 241.

[0106] By arranging the fourth pipeline 241 and the third regulating valve 242, the excess liquid refrigerant in the first pipeline 211 and / or the second pipeline 221 can be led to the evaporator 12.

[0107] For example: when the first regulating valve 213 or the second regulating valve 222 has been adjusted (opened small enough), and there is still a situation where △P is greater than or equal to the preset pressure value (the bearing capacity required to support the rotating shaft 16), the third regulating valve 242 can be opened to allow part of the liquid refrigerant to flow to the evaporator 12, and finally make △P equal to the preset pressure value (the bearing capacity required to support the rotating shaft 16).

[0108] As Figure 2 shown, in some embodiments, the refrigeration cycle circuit 1 further includes a flash tank 14, the liquid storage part includes the bottom of the flash tank 14, the liquid supply assembly 2 includes a fifth pipeline 251, the input end of the fifth pipeline 251 is communicated with the bottom of the flash tank 14, and the output end of the fifth pipeline 251 is communicated with the hydrostatic bearing 15.

[0109] The bottom of the flash tank 14 is the bottom of the part where the liquid refrigerant remains in the flash tank 14.

[0110] The pressure in the flash tank 14 is higher than that in the evaporator 12, and the remaining liquid refrigerant is less than that in the evaporator 12. Therefore, in stages such as when the unit is started, stopped, or running at low speed, the secondary option is to take liquid from the bottom of the flash tank 14.

[0111] In some embodiments, the liquid supply assembly 2 further includes a second pump 252, and the second pump 252 is arranged on the fifth pipeline 251. By providing power through the second pump 252, the liquid refrigerant remaining in the flash tank 14 is led to the hydrostatic bearing 15.

[0112] In some embodiments, the liquid supply assembly 2 further includes a fourth regulating valve 253. The fourth regulating valve 253 is disposed in the fifth pipeline 251 and is configured to regulate the on-off state and the flow area of the fifth pipeline 251.

[0113] When the fourth regulating valve 253 is closed, the fifth pipeline 251 is disconnected. By increasing the opening degree of the fourth regulating valve 253, the pressure of the liquid refrigerant flowing to the hydrostatic bearing 15 increases, and the liquid flow rate entering the hydrostatic bearing 15 increases; conversely, by decreasing the opening degree of the fourth regulating valve 253, the pressure of the liquid refrigerant flowing to the hydrostatic bearing 15 decreases, and the liquid flow rate entering the hydrostatic bearing 15 decreases.

[0114] The regulation of the opening degree of the fourth regulating valve 253 is based on: adjusting the opening degree of the fourth regulating valve 253 so that after subtracting the ambient pressure of the hydrostatic bearing 15 inside the compressor 11 from the pressure of the liquid refrigerant flowing to the hydrostatic bearing 15, it can still meet the bearing capacity required to support the rotating shaft 16.

[0115] Through the descriptions of the above various embodiments, the liquid storage parts of the refrigeration cycle circuit 1 can include not only the evaporator 12, the condenser 13 or the flash evaporator 14, but also the pipelines in the refrigeration cycle circuit 1. The liquid refrigerant retained in the pipelines in the refrigeration cycle circuit 1 can also be supplied to the hydrostatic bearing 15. No matter which liquid storage part in the refrigeration cycle circuit 1 the liquid is taken from, it is: △P = P1 - P0, where △P is the supply hydraulic pressure difference, and the purpose is to make △P equal to the bearing capacity required to support the rotating shaft 16, P1 is the pressure of the liquid refrigerant provided by the liquid supply assembly 2 to the hydrostatic bearing 15, and P0 is the ambient pressure of the hydrostatic bearing 15 inside the compressor 11.

[0116] In some embodiments, the liquid supply assembly 2 further includes a fourth one-way valve 254. The fourth one-way valve 254 is disposed in the fifth pipeline 251 and is used to prevent the liquid refrigerant in the hydrostatic bearing 15 from flowing back to the flash evaporator 14.

[0117] In some embodiments, the liquid supply assembly 2 further includes a third filter 255. The third filter 255 is disposed in the fifth pipeline 251 and is used to filter the liquid refrigerant flowing from the fifth pipeline 251 to the hydrostatic bearing 15, preventing impurities in the liquid refrigerant from clogging the micropores 151 on the hydrostatic bearing 15.

[0118] In some embodiments, the liquid supply assembly 2 includes a third pipeline 231. The output end of the fifth pipeline 251 is communicated with the hydrostatic bearing 15 through the third pipeline 231.

[0119] In some embodiments, the liquid supply assembly 2 further includes a fourth pipeline 241 and a third regulating valve 242. The input end of the fourth pipeline 241 communicates with the third pipeline 231, the output end of the fourth pipeline 241 communicates with the evaporator 12, the third regulating valve 242 is arranged on the fourth pipeline 241, and the third regulating valve 242 is configured to regulate the on-off and flow area of the fourth pipeline 241.

[0120] In some embodiments, the diameter range of the micropores 151 is 0.01 mm to 0.2 mm.

[0121] For heavy-duty and high-speed centrifugal compressors, in order to be more stable, the hydrostatic bearings inside them need to have a higher load-bearing capacity.

[0122] In the embodiments of the present disclosure, the hydrostatic bearings in the compressor adopt microporous hydrostatic gas bearings, and liquid refrigerant is used as the lubricant, which can effectively improve the load-bearing capacity, impact resistance and stability of the microporous hydrostatic gas bearings, and thus improve the operation reliability of the refrigeration centrifugal chiller. The micropores 151 on the hydrostatic bearing 15 are generally realized by laser drilling, with high precision, which is beneficial to ensuring the stability of liquid throttling at the micropores; on the premise of the same bearing capacity of the bearing, the smaller the aperture of the micropores, the more micropores are required, and the more uniform the bearing capacity distribution is.

[0123] Some embodiments also provide a liquid supply method for the hydrostatic bearing 15 of the above-mentioned refrigeration system, which includes:

[0124] Providing a refrigeration cycle loop 1, the refrigeration cycle loop 1 includes a compressor 11, the compressor 11 includes a hydrostatic bearing 15 and a rotating shaft 16, the hydrostatic bearing 15 supports the rotating shaft 16, and a plurality of micropores 151 are arranged on the outer periphery of the hydrostatic bearing 15; and

[0125] Providing a liquid supply assembly 2, guiding the liquid refrigerant at the liquid storage part of the refrigeration cycle loop 1 to the hydrostatic bearing 15 through the liquid supply assembly 2, and enabling the liquid refrigerant to enter between the hydrostatic bearing 15 and the rotating shaft 16 through the micropores 151 on the hydrostatic bearing 15.

[0126] In some embodiments, the refrigeration cycle loop 1 further includes an evaporator 12, the liquid storage part includes the bottom of the evaporator 12, the liquid supply assembly 2 includes a first pipeline 211, a first pump 212 and a first regulating valve 213, the input end of the first pipeline 211 communicates with the bottom of the evaporator 12, the output end of the first pipeline 211 communicates with the hydrostatic bearing 15, and the first pump 212 and the first regulating valve 213 are arranged on the first pipeline 211;

[0127] The step of guiding the liquid refrigerant at the liquid storage part of the refrigeration cycle loop 1 to the hydrostatic bearing 15 through the liquid supply assembly 2 includes:

[0128] During the startup, shutdown, or low-speed operation stage of the compressor 11, the first pump 212 and the first regulating valve 213 are opened. Under the action of the first pump 212, the liquid refrigerant at the bottom of the evaporator 12 flows towards the hydrostatic bearing 15 and enters the space between the hydrostatic bearing 15 and the rotating shaft 16 through the micropores 151 on the hydrostatic bearing 15. At the same time, the flow area of the first pipeline 211 is adjusted through the first regulating valve 213, thereby adjusting the pressure of the liquid refrigerant entering the space between the hydrostatic bearing 15 and the rotating shaft 16 to make △P equal to the bearing capacity required to support the rotating shaft 16.

[0129] In some embodiments, the refrigeration cycle loop 1 further includes a condenser 13, the liquid storage part includes the bottom of the condenser 13, the liquid supply assembly 2 further includes a second pipeline 221 and a second regulating valve 222. The input end of the second pipeline 221 is communicated with the bottom of the condenser 13, the output end of the second pipeline 221 is communicated with the hydrostatic bearing 15, and the second regulating valve 222 is arranged on the second pipeline 221;

[0130] The step of guiding the liquid refrigerant in the liquid storage part of the refrigeration cycle loop 1 to the hydrostatic bearing 15 through the liquid supply assembly 2 further includes:

[0131] After the pressure difference is established during the high-speed operation of the compressor 11, the second regulating valve 222 is opened, the first pump 212 and the first regulating valve 213 are gradually closed. The pressure in the condenser 13 causes the liquid refrigerant at the bottom of the condenser 13 to flow towards the hydrostatic bearing 15 and enter the space between the hydrostatic bearing 15 and the rotating shaft 16 through the micropores 151 on the hydrostatic bearing 15. At the same time, the flow area of the second pipeline 221 is adjusted through the second regulating valve 222, thereby adjusting the pressure of the liquid refrigerant entering between the hydrostatic bearing 15 and the shaft to make △P equal to the bearing capacity required to support the rotating shaft 16.

[0132] In some embodiments, the liquid supply assembly 2 includes a third pipeline 231, a fourth pipeline 241, and a third regulating valve 242. The output ends of the first pipeline 211 and the second pipeline 221 are both communicated with the hydrostatic bearing 15 through the third pipeline 231; the input end of the fourth pipeline 241 is communicated with the third pipeline 231, the output end of the fourth pipeline 241 is communicated with the evaporator 12, and the third regulating valve 242 is arranged on the fourth pipeline 241.

[0133] During the startup, shutdown, or low-speed operation stage of the compressor 11, after the first regulating valve 213 is adjusted (the opening of the first regulating valve 213 is small enough), if the pressure of the liquid refrigerant flowing from the first pipeline 211 to the space between the hydrostatic bearing 15 and the rotating shaft 16 is greater than the preset pressure value (the bearing capacity required to support the rotating shaft 16), then the third regulating valve 242 is opened. Through the cooperation of the third regulating valve 242 and the first regulating valve 213, the pressure of the liquid refrigerant flowing to the space between the hydrostatic bearing 15 and the shaft is adjusted to make the pressure equal to the preset pressure (the bearing capacity required to support the rotating shaft 16).

[0134] After the compressor 11 runs at high speed to establish a pressure difference, when the first pump 212 and the first regulating valve 213 are closed and the second regulating valve 222 is adjusted (the opening of the second regulating valve 222 is small enough), if the pressure of the liquid refrigerant flowing from the second pipeline 221 between the hydrostatic bearing 15 and the rotating shaft 16 is greater than the preset pressure value (the bearing capacity required to support the rotating shaft 16), the third regulating valve 242 is opened. By cooperating with the second regulating valve 222 through the third regulating valve 242, the pressure of the liquid refrigerant flowing between the hydrostatic bearing 15 and the rotating shaft 16 is adjusted to make the pressure equal to the preset pressure value (the bearing capacity required to support the rotating shaft 16).

[0135] The following will combine with the attached Figure 1 to describe in detail some specific embodiments of the refrigeration system.

[0136] As Figure 1 shown, in some specific embodiments, the refrigeration system includes a refrigeration cycle circuit 1 and a liquid supply assembly 2.

[0137] Among them, the refrigeration cycle circuit 1 includes a compressor 11, an evaporator 12, a condenser 13, a flash tank 14, a first throttle valve 111 and a second throttle valve 112.

[0138] The compressor 11 includes a hydrostatic bearing 15 and a rotating shaft 16. The hydrostatic bearing 15 supports the rotating shaft 16, and a plurality of micropores 151 are provided on the outer periphery of the hydrostatic bearing 15. The rotating shaft 16 is a motor shaft. The compressor 11 is a centrifugal compressor.

[0139] During operation, the centrifugal compressor is powered on and drives the motor shaft to rotate, so that the compressor impeller sucks in the low-pressure gaseous refrigerant from the evaporator 12. Through the work of the compressor impeller, the pressure of the gaseous refrigerant increases and flows to the condenser 13. Most of the high-pressure gaseous refrigerant exchanges heat inside the condenser 13 and becomes high-pressure liquid refrigerant. After passing through the first throttle valve 111, the high-pressure liquid refrigerant undergoes the first throttling and flows to the flash tank 14. The refrigerant gas flashed during the first throttling process flows to the compressor 11 as a makeup gas, while the refrigerant liquid flows to the second throttle valve 112. After the second throttling, a low-temperature and low-pressure liquid refrigerant is formed and flows to the evaporator 12. After the liquid refrigerant exchanges heat inside the evaporator 12, it evaporates into a gas and flows to the compressor 11, and this cycle continues.

[0140] The liquid supply assembly 2 includes a first pipeline 211. The input end of the first pipeline 211 is communicated with the bottom of the evaporator 12, and the output end of the first pipeline 211 is communicated with the hydrostatic bearing 15. A first pump 212, a first regulating valve 213, a first check valve 214 and a first filter 215 are provided on the first pipeline 211.

[0141] The liquid supply assembly 2 includes a second pipeline 221. The input end of the second pipeline 221 is communicated with the bottom of the condenser 13, and the output end of the second pipeline 221 is communicated with the hydrostatic bearing 15. A second regulating valve 222, a second check valve 223 and a second filter 224 are provided on the second pipeline 221.

[0142] The liquid supply assembly 2 includes a third pipeline 231. The output ends of the first pipeline 211 and the second pipeline 221 are both communicated with the hydrostatic bearing 15 through the third pipeline 231. A third check valve 232 and a fourth sensor 233 are provided on the third pipeline 231.

[0143] The liquid supply of the liquid supply assembly 2 may include the following two cases.

[0144] The first case: During stages such as when the unit is starting up, shutting down or running at a low speed, at this time the internal pressure of the condenser 13 is low and is not sufficient to supply enough liquid refrigerant to the hydrostatic bearing 15. Therefore, the second regulating valve 222 is closed at this time, the first pump 212 and the first regulating valve 213 are opened. Under the action of the first pump 212, the liquid refrigerant from the bottom of the evaporator 12 flows successively through the first filter 215, the first pump 212, the first check valve 214, the first regulating valve 213, the third check valve 232, the fourth pressure sensor 233, the liquid inlet hole 171 on the bearing seat 17, and enters the liquid storage cavity 18. The liquid refrigerant in the liquid storage cavity 18 enters the gap 110 between the hydrostatic bearing 15 and the rotating shaft 16 through the micropores 151 on the hydrostatic bearing 15.

[0145] Among them, the first pump 212 drives the liquid refrigerant to flow from the evaporator 12 to the compressor 11 and increases the pressure of the liquid refrigerant. The form of the first pump 212 can be divided into a fixed-frequency pump and a variable-frequency pump.

[0146] The first pump 212 can jointly control the pressure in the third pipeline 231 with the first regulating valve 213 and the third regulating valve 242.

[0147] Specifically, when the first pump 212 is a fixed-frequency pump, at this time the pressure in the third pipeline 231 is mainly adjusted by the opening degree of the first regulating valve 213, so as to control the liquid flow rate entering the hydrostatic bearing 15. For example: increasing the opening degree of the first regulating valve 213, the pressure in the third pipeline 231 increases, and the liquid flow rate entering the hydrostatic bearing 15 increases; conversely, decreasing the opening degree of the first regulating valve 213, the pressure in the third pipeline 231 decreases, and the liquid flow rate entering the hydrostatic bearing 15 decreases.

[0148] When the pressure in the third pipeline 231 is too high, and at this time the first regulating valve 213 is already small enough, since the first pump 212 is a fixed-frequency pump and cannot adjust the flow rate by itself, at this time the opening degree of the third regulating valve 242 will be increased to bypass part of the liquid refrigerant to the evaporator 12, thereby reducing the pressure in the third pipeline 231.

[0149] Similarly, when the pressure in the third pipeline 231 is too low and the opening of the first regulating valve 213 has been increased to the maximum at this time, the opening of the third regulating valve 242 will be reduced, or even the third regulating valve 242 will be closed, so as to increase the pressure in the third pipeline 231.

[0150] When the first pump 212 is a variable-frequency pump, it can adjust the flow rate by changing its rotational speed, and jointly control the pressure in the third pipeline 231 with the first regulating valve 213 and the third regulating valve 242. Compared with a fixed-frequency pump, a variable-frequency pump can further improve the pressure regulation ability.

[0151] Due to the liquid inlet hole 171 on the bearing housing 17 and the pressure in the liquid storage cavity 18 being greater than that of the evaporator 12, by setting the third one-way valve 232, it is possible to prevent the refrigerant from flowing back from the liquid inlet hole 171 and the liquid storage cavity 18 to the evaporator 12 when the third regulating valve 242 is opened.

[0152] Since there will be a pressure drop when the liquid refrigerant passes through the third one-way valve 232, in order to ensure the accuracy of the supply hydraulic pressure difference △P, the third one-way valve 232 is preferably placed upstream of the fourth pressure sensor 233.

[0153] In the above embodiment, it is preferably to take liquid from the bottom of the evaporator 12. According to the working principle of the refrigeration centrifugal unit, during operation, the pressure in the evaporator 12 is the lowest. Therefore, under the action of the system pressure difference, the liquid refrigerant stored inside the evaporator 12 is the most, and it is also the component with the most liquid refrigerant remaining even in the case of shutdown. Therefore, it is preferred to take liquid from the bottom of the evaporator 12, and the secondary option is to take liquid from the condenser 13 and the flash tank 14.

[0154] As Figure 2 shown, the working principle of taking liquid from the bottom of the flash tank 14 is similar to that of taking liquid from the bottom of the evaporator 12. Because the unit is in a state such as startup, shutdown, or low-speed operation at this time, the internal pressure of the flash tank 14 or the evaporator 12 is relatively low. Therefore, the liquid refrigerant in the flash tank 14 is pumped to the hydrostatic bearing 15 by the second pump 252.

[0155] The second case: After the pressure difference is established during the high-speed operation of the unit, when the internal pressure of the condenser 13 minus the internal environment pressure of the compressor is greater than the preset pressure value, the second regulating valve 222 is opened, and the first pump 212 and the first regulating valve 213 are gradually closed. Among them, the closing rates of the first pump 212 and the first regulating valve 213 are determined by the change of the feedback supply hydraulic pressure difference △P.

[0156] During the process of gradually closing the first pump 212 and the first regulating valve 213, if the supply hydraulic pressure difference △P is lower than the preset pressure value, it is necessary to increase the opening degree of the second regulating valve 222, reduce the closing rate of the first pump 212 and the first regulating valve 213 until the supply hydraulic pressure difference △P meets the preset pressure value, and finally completely close the first pump 212 and the first regulating valve 213. At this time, the system uses its own pressure difference to continuously supply liquid to the hydrostatic bearing 15 from the condenser 13, reducing the continuous working time of the first pump 212.

[0157] If the pressure in the condenser 13 is too high during operation, then by controlling the third regulating valve 242, a part of the liquid refrigerant is bypassed to the evaporator 12, so as to keep the supply hydraulic pressure difference △P equal to the preset pressure value.

[0158] In the second case described above, it is preferred to take liquid from the bottom of the condenser 13 because when the centrifuge is working, the internal pressure of the condenser 13 is the highest, and there is enough margin to meet the supply hydraulic pressure difference △P reaching the preset pressure value. The second choice is to take liquid from the bottom of the flash tank.

[0159] Based on the above embodiments of the present invention, in the case of no explicit negation, the technical features of one embodiment can be beneficially combined with one or more other embodiments.

[0160] Although some specific embodiments of the present invention have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present invention. Those skilled in the art should understand that the above embodiments can be modified or some technical features can be equivalently replaced without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A refrigeration system, characterized in that, Comprising: A refrigeration cycle circuit (1), the refrigeration cycle circuit (1) includes a compressor (11), the compressor (11) includes a hydrostatic bearing (15) and a rotating shaft (16), the hydrostatic bearing (15) supports the rotating shaft (16), and a plurality of micropores (151) are provided on the outer periphery of the hydrostatic bearing (15); A liquid supply assembly (2), which communicates with the liquid storage part of the refrigeration cycle circuit (1) and the hydrostatic bearing (15), the liquid storage part has liquid refrigerant, the liquid supply assembly (2) is configured to direct the liquid refrigerant in the liquid storage part to the hydrostatic bearing (15), and make the liquid refrigerant enter between the hydrostatic bearing (15) and the rotating shaft (16) through the micropores (151); The refrigeration cycle circuit (1) further includes an evaporator (12), the liquid storage part includes the bottom of the evaporator (12), the liquid supply assembly (2) includes a first pipeline (211), the input end of the first pipeline (211) communicates with the bottom of the evaporator (12), and the output end of the first pipeline (211) communicates with the hydrostatic bearing (15); the refrigeration cycle circuit (1) further includes a condenser (13), the liquid storage part includes the bottom of the condenser (13), the liquid supply assembly (2) further includes a second pipeline (221), the input end of the second pipeline (221) communicates with the bottom of the condenser (13), and the output end of the second pipeline (221) communicates with the hydrostatic bearing (15); and Wherein, during the startup, shutdown or low-speed operation stage of the unit, liquid refrigerant is taken from the evaporator (12) to achieve continuous and stable liquid supply to the hydrostatic bearing (15); When the pressure difference is established during the high-speed operation of the unit, high-pressure liquid refrigerant is taken from the condenser (13) to continue to achieve continuous and stable liquid supply to the hydrostatic bearing (15); The liquid supply assembly (2) further includes a third pipeline (231), a fourth pipeline (241), a first regulating valve (213), a second regulating valve (222) and a third regulating valve (242). The output ends of the first pipeline (211) and the second pipeline (221) are both connected to the hydrostatic bearing (15) through the third pipeline (231); the input end of the fourth pipeline (241) is connected to the third pipeline (231), the output end of the fourth pipeline (241) is connected to the evaporator (12), and the third regulating valve (242) is provided on the fourth pipeline (241); the first regulating valve (213) is provided on the first pipeline (221), and the second regulating valve (222) is provided on the second pipeline (221); During the startup, shutdown or low-speed operation stage of the compressor (11), if the pressure of the liquid refrigerant flowing from the first pipeline (211) between the hydrostatic bearing (15) and the rotating shaft (16) is greater than the preset pressure value, the third regulating valve (242) is opened, and through the cooperation of the third regulating valve (242) and the first regulating valve (213), the pressure of the liquid refrigerant flowing between the hydrostatic bearing (15) and the shaft is adjusted; After the compressor (11) operates at high speed to establish a pressure difference, in the state where the first pump (212) and the first regulating valve (213) are closed, if the pressure of the liquid refrigerant flowing in the second pipeline (221) between the hydrostatic bearing (15) and the rotating shaft (16) is greater than the preset pressure value, the third regulating valve (242) is opened, and in cooperation with the second regulating valve (222), the pressure of the liquid refrigerant flowing between the hydrostatic bearing (15) and the rotating shaft (16) is regulated.

2. The refrigeration system according to claim 1, characterized in that, The liquid supply assembly (2) further includes a first pump (212), and the first pump (212) is arranged in the first pipeline (211).

3. The refrigeration system according to claim 1, wherein, The input end of the fourth pipeline (241) is communicated with the output end of the first pipeline (211).

4. The refrigeration system according to claim 1, characterized in that, The input end of the fourth pipeline (241) is communicated with the output end of the second pipeline (221).

5. The refrigeration system according to claim 1 or 2, characterized in that, The refrigeration cycle circuit (1) further includes a flash tank (14), the liquid storage part includes the bottom of the flash tank (14), the liquid supply assembly (2) includes a fifth pipeline (251), the input end of the fifth pipeline (251) is communicated with the bottom of the flash tank (14), and the output end of the fifth pipeline (251) is communicated with the hydrostatic bearing (15).

6. The refrigeration system according to claim 5, characterized in that, The liquid supply assembly (2) further includes a second pump (252), and the second pump (252) is arranged in the fifth pipeline (251).

7. The refrigeration system according to claim 6, wherein The liquid supply assembly (2) further includes a fourth regulating valve (253), the fourth regulating valve (253) is arranged in the fifth pipeline (251), and the fourth regulating valve (253) is configured to regulate the on-off and flow area of the fifth pipeline (251).

8. The refrigeration system according to claim 1 or 2, characterized in that, The diameter range of the micropores (151) is 0.01 mm to 0.2 mm.

9. A liquid supply method for a hydrostatic bearing of a refrigeration system according to any one of claims 1 to 8, which includes: Providing a refrigeration cycle circuit (1), the refrigeration cycle circuit (1) includes a compressor (11), the compressor (11) includes a hydrostatic bearing (15) and a rotating shaft (16), the hydrostatic bearing (15) supports the rotating shaft (16), and a plurality of micropores (151) are arranged on the outer periphery of the hydrostatic bearing (15); and Providing a liquid supply assembly (2), guiding the liquid refrigerant in the liquid storage part of the refrigeration cycle circuit (1) to the hydrostatic bearing (15) through the liquid supply assembly (2), and enabling the liquid refrigerant to enter between the hydrostatic bearing (15) and the rotating shaft (16) through the micropores (151) on the hydrostatic bearing (15).

10. The liquid supply method for a hydrostatic bearing of a refrigeration system according to claim 9, wherein, The refrigeration cycle circuit (1) further includes an evaporator (12), the liquid storage part includes the bottom of the evaporator (12), the liquid supply assembly (2) includes a first pipeline (211), a first pump (212) and a first regulating valve (213), the input end of the first pipeline (211) is communicated with the bottom of the evaporator (12), the output end of the first pipeline (211) is communicated with the hydrostatic bearing (15), and the first pump (212) and the first regulating valve (213) are arranged in the first pipeline (211); The step of leading the liquid refrigerant at the liquid storage part of the refrigeration cycle circuit (1) to the hydrostatic bearing (15) through the liquid supply assembly (2) includes: During the startup, shutdown or low-speed operation stage of the compressor (11), the first pump (212) and the first regulating valve (213) are opened. Under the action of the first pump (212), the liquid refrigerant at the bottom of the evaporator (12) flows to the hydrostatic bearing (15), and enters between the hydrostatic bearing (15) and the rotating shaft (16) through the micropores (151) on the hydrostatic bearing (15). At the same time, the flow area of the first pipeline (211) is adjusted through the first regulating valve (213), and then the pressure of the liquid refrigerant entering between the hydrostatic bearing (15) and the rotating shaft (16) is adjusted.

11. The liquid supply method for the hydrostatic bearing of the refrigeration system according to claim 10, wherein, The refrigeration cycle circuit (1) further includes a condenser (13), the liquid storage part includes the bottom of the condenser (13), the liquid supply assembly (2) further includes a second pipeline (221) and a second regulating valve (222), the input end of the second pipeline (221) is communicated with the bottom of the condenser (13), the output end of the second pipeline (221) is communicated with the hydrostatic bearing (15), and the second regulating valve (222) is arranged on the second pipeline (221); The step of leading the liquid refrigerant at the liquid storage part of the refrigeration cycle circuit (1) to the hydrostatic bearing (15) through the liquid supply assembly (2) further includes: After the pressure difference is established during the high-speed operation of the compressor (11), the second regulating valve (222) is opened, the first pump (212) and the first regulating valve (213) are gradually closed, and the pressure in the condenser (13) causes the liquid refrigerant at the bottom of the condenser (13) to flow to the hydrostatic bearing (15), and enters between the hydrostatic bearing (15) and the rotating shaft (16) through the micropores (151) on the hydrostatic bearing (15). At the same time, the flow area of the second pipeline (221) is adjusted through the second regulating valve (222), and then the pressure of the liquid refrigerant entering between the hydrostatic bearing (15) and the shaft is adjusted.

12. The liquid supply method for the hydrostatic bearing of the refrigeration system according to claim 10, wherein, The liquid supply assembly (2) includes a third pipeline (231), a fourth pipeline (241) and a third regulating valve (242). The output ends of the first pipeline (211) and the second pipeline (221) are both communicated with the hydrostatic bearing (15) through the third pipeline (231); the input end of the fourth pipeline (241) is communicated with the third pipeline (231), the output end of the fourth pipeline (241) is communicated with the evaporator (12), and the third regulating valve (242) is arranged on the fourth pipeline (241); During the startup, shutdown or low-speed operation stage of the compressor (11), if the pressure of the liquid refrigerant flowing from the first pipeline (211) between the hydrostatic bearing (15) and the rotating shaft (16) is greater than the preset pressure value, the third regulating valve (242) is opened, and the pressure of the liquid refrigerant flowing between the hydrostatic bearing (15) and the shaft is adjusted through the cooperation of the third regulating valve (242) and the first regulating valve (213).

13. The liquid supply method of the hydrostatic bearing of the refrigeration system according to claim 11, wherein, The liquid supply assembly (2) includes a third pipeline (231), a fourth pipeline (241) and a third regulating valve (242). The output ends of the first pipeline (211) and the second pipeline (221) are both communicated with the hydrostatic bearing (15) through the third pipeline (231); the input end of the fourth pipeline (241) is communicated with the third pipeline (231), the output end of the fourth pipeline (241) is communicated with the evaporator (12), and the third regulating valve (242) is arranged on the fourth pipeline (241); After the compressor (11) operates at a high speed to establish a pressure difference, in the state where the first pump (212) and the first regulating valve (213) are closed, if the pressure of the liquid refrigerant flowing from the second pipeline (221) between the hydrostatic bearing (15) and the rotating shaft (16) is greater than the preset pressure value, the third regulating valve (242) is opened, and the pressure of the liquid refrigerant flowing between the hydrostatic bearing (15) and the rotating shaft (16) is adjusted by the cooperation of the third regulating valve (242) and the second regulating valve (222).

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