Fluid supply system for a compressor and method of supplying

Abstract

The present disclosure provides a fluid supply system for a compressor, which is applied to a refrigeration unit comprising at least a liquid storage device, the fluid supply system for the compressor comprising: a liquid supplement module receiving liquid refrigerant by gravity of refrigerant liquid in the liquid storage device; and a supply module receiving liquid refrigerant and / or gaseous refrigerant and / or liquid-gas refrigerant mixture provided by the liquid supplement module according to a pressure difference between a pressure of the supply module and a pressure of the liquid supplement module; and the supply module providing liquid refrigerant and / or gaseous refrigerant and / or liquid-gas refrigerant mixture to a hydrostatic gas bearing used in the compressor; wherein the liquid supplement module further comprises a first liquid supplement module and a second liquid supplement module, the first liquid supplement module and the second liquid supplement module being connected to different liquid storage devices. The present disclosure also provides a fluid supply method for a compressor.

Description

Technical Field

[0001] This disclosure relates to a fluid supply system and method for a compressor. Background Technology

[0002] Currently, refrigeration compressors commonly use oil-lubricated bearings and suspension bearings.

[0003] Compressors using oil-lubricated bearings require an additional lubrication oil supply system and a lubrication oil-refrigerant separation system to separate the lubricating oil that has entered the refrigerant. After a period of operation, lubricating oil will also deposit on the inner surface of the copper tubes in the condenser and evaporator, reducing the performance of the heat exchanger. Regular cleaning of the inner surface of the copper tubes in the condenser and evaporator, as well as regular replenishment of refrigerant and lubricating oil, are necessary. In short, the use of lubricating oil increases system complexity, reduces system reliability and performance, and increases maintenance costs.

[0004] Suspension bearings include magnetic suspension bearings and air suspension bearings, with air suspension bearings further divided into hydrostatic bearings and hydrodynamic bearings. Hydrostatic bearings require external pressurization, with a gas / liquid supply system continuously and stably supplying the bearing with a gas, liquid, or gas-liquid two-phase refrigerant medium to provide support and lubrication for the rotor. Nevertheless, due to the high rotational accuracy and low internal leakage of hydrostatic air bearings, compressor performance and lifespan are improved, leading to increased interest in the application of hydrostatic air bearing compressors in the refrigeration industry.

[0005] The storage tank (also known as the gas supply tank) provides lubricating medium to the bearings. In a refrigeration system, the lubricating medium is the refrigerant circulating in the system. Taking a static pressure air-bearing bearing with its exhaust connected to the evaporator as an example, the bearing pressure difference is the pressure difference between the storage tank and the evaporator. During unit start-up and shutdown, operating condition adjustments, and various operating states, the bearing pressure difference needs to remain constant, allowing only very small fluctuations. Therefore, a practically useful bearing medium supply system must possess the following characteristics:

[0006] 1. The storage tank must be able to obtain liquid or gaseous refrigerant under various operating conditions. For example, unit startup can be divided into cold start and hot start. During cold start, the evaporator and condenser temperatures are similar, and the location of refrigerant accumulation depends on the unit's structure. Horizontal units have liquid refrigerant accumulation at the bottom of both the evaporator and condenser, while vertical units only have liquid refrigerant in the condenser. During hot start, the evaporator temperature is significantly lower than the condenser temperature. Driven by saturation pressure, liquid refrigerant is driven to the evaporator, regardless of whether the unit is horizontal or vertical. Units using two-stage and multi-stage compression may sometimes have liquid refrigerant in the economizer. Therefore, the bearing gas supply system must first have the ability to determine the location of liquid refrigerant, and secondly, the ability to deliver refrigerant to the gas supply tank or storage tank with low power consumption.

[0007] 2. The bearing fluid supply pressure must be able to promptly adapt to changes in the evaporator pressure to maintain a stable bearing differential pressure. If the time lag is too long, pressure fluctuations will exceed the allowable range. One solution is to extend the unit start-up, shutdown, and condition adjustment processes; however, this results in poor unit adaptability and limits its application.

[0008] Figure 1 An existing gas supply system is shown, which draws liquid from the bottom of the evaporator / condenser / economizer, filters it, and then pressurizes it with an oil-free pump before feeding it into a gas supply tank. The gas supply tank then supplies fluid to the bearing, and the bearing vent is connected to the evaporator. To ensure stable supply pressure, the gas supply tank contains a heater, a pressure sensor, a level gauge, and other devices. Some systems do not have a gas supply tank and instead supply lubricating medium directly to the bearing via a pump.

[0009] A refrigerant pump is a power machine that pressurizes and transports liquids. Only a small amount of gas is allowed at its inlet and outlet. Otherwise, the refrigerant pump will run dry, the liquid will not be able to enter the refrigerant pump, and eventually the refrigerant pump will overheat and burn out.

[0010] However, in Figure 1 In the system shown, gas appears both upstream and downstream of the refrigerant pump. The upstream gas occurrence can be attributed to the following: 1. Piping losses upstream of the pump, leading to a decrease in saturated liquid pressure and partial vaporization; 2. Pressure loss from the filter; 3. Heat exchange between the upstream piping and the external environment. If the liquid temperature in the piping is lower than the ambient temperature, the environment heats the piping, causing internal liquid vaporization. This phenomenon is particularly noticeable when drawing liquid from the evaporator; 4. During refrigerant pump suction, the inlet pressure decreases, causing refrigerant vaporization. The degree of vaporization increases with the pump's rotational speed. This phenomenon is also particularly noticeable when drawing liquid from the evaporator, as the low evaporator liquid pressure necessitates a higher pump speed to obtain the required head. Downstream gas mainly occurs after the unit has been shut down for an extended period, causing liquid vaporization in the piping and making start-up difficult. It should be noted that after the unit starts operating, the fluid in the downstream piping is in a subcooled state, making gas generation highly unlikely.

[0011] Therefore, the disclosed technology can cause the refrigerant pump to malfunction due to multiple factors such as environmental heat exchange, filter loss, and high pressure head when liquid needs to be drawn from the evaporator. This leads to frequent start-stop of the unit, and when the unit is in a hot state, the refrigerant pump may be damaged and the unit may be unable to start again. Summary of the Invention

[0012] To address one of the aforementioned technical problems, this disclosure provides a fluid supply system and method for a compressor, characterized by the absence of a refrigerant pump and a liquid position sensor.

[0013] According to one aspect of this disclosure, a fluid supply system for a compressor is provided, which is applied to a refrigeration unit, the refrigeration unit including at least a liquid storage device, the fluid supply system for the compressor comprising:

[0014] A liquid replenishment module, wherein the liquid replenishment module receives liquid refrigerant by gravity in the liquid refrigerant storage device; and

[0015] The supply module receives liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant from the replenishment module based on the pressure difference between the supply module and the replenishment module; and the supply module provides liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant to the hydrostatic air bearing used in the compressor;

[0016] The replenishment module further includes a first replenishment module and a second replenishment module, which are connected to different liquid storage devices.

[0017] According to at least one embodiment of the fluid supply system for a compressor disclosed herein, a regulating valve is provided between the replenishment module and the supply module.

[0018] According to at least one embodiment of the fluid supply system for a compressor disclosed herein, the replenishment module includes a replenishment tank connected to the liquid storage device via a first pipeline. The connection between the first pipeline and the liquid storage device is located at the lower part of the liquid storage device. A first switching valve is provided on the first pipeline, and liquid refrigerant enters the replenishment tank through the first pipeline.

[0019] According to at least one embodiment of the fluid supply system for a compressor disclosed herein, the upper part of the replenishment tank is further connected to the upper part of the liquid storage device via a second pipeline, wherein the second pipeline is provided with a second switching valve so as to enable the flow of gas from the replenishment tank to the liquid storage device via the second pipeline.

[0020] According to at least one embodiment of the fluid supply system for a compressor disclosed herein, a first heating device is provided inside the replenishment tank.

[0021] According to at least one embodiment of the fluid supply system for a compressor disclosed herein, the replenishment tank is provided with a first pressure sensor.

[0022] According to at least one embodiment of the present disclosure, a fluid supply system for a compressor includes a supply tank connected to a replenishment module and a static pressure air bearing.

[0023] According to at least one embodiment of the fluid supply system for a compressor disclosed herein, a second heating device is provided inside the supply tank.

[0024] According to at least one embodiment of the fluid supply system for a compressor disclosed herein, the supply tank is provided with a second pressure sensor.

[0025] According to another aspect of this disclosure, a fluid supply method for a compressor is provided, comprising: a replenishment mode and a supply mode; wherein:

[0026] The fluid replacement modes include:

[0027] Control the second switching valve to make the pressure of the gaseous refrigerant in the liquid replenishment module and the liquid storage device the same;

[0028] Control the first switching valve so that the liquid refrigerant in the liquid storage device flows to the liquid replenishment module under the action of gravity;

[0029] Control the liquid replenishment module to increase the pressure of the gaseous refrigerant within it; and

[0030] Control the regulating valve to allow the liquid refrigerant and / or gaseous refrigerant in the replenishment module to flow to the supply module;

[0031] The supply modes include:

[0032] The control supply module enables the supply module to provide liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant to the hydrostatic air bearing.

[0033] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, the regulating valve remains closed while liquid refrigerant in the liquid storage device flows to the replenishment module.

[0034] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, during the flow of liquid refrigerant and / or gaseous refrigerant from the replenishment module to the supply module, the opening of a regulating valve is controlled so that pressure fluctuations within the supply module are within a set range.

[0035] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, during the flow of liquid refrigerant and / or gaseous refrigerant from the replenishment module to the supply module, the regulating valve is closed after the pressure difference between the replenishment module and the supply module decreases to a set value.

[0036] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, liquid refrigerant is supplied to the liquid replenishment module after the regulating valve is closed.

[0037] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, the pressure of the gaseous refrigerant in the replenishment module is increased by heating the liquid refrigerant in the replenishment module.

[0038] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, the content of residual liquid refrigerant in the replenishment module and / or supply module is determined based on the power consumption-liquid quantity relationship.

[0039] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, a liquid replenishment mode is executed at least once during the refrigeration unit start-up preparation phase.

[0040] According to at least one embodiment of the fluid supply method for a compressor of the present disclosure, when the compressor is started, the method includes the following steps:

[0041] a) Close the first switch valve of the liquid replenishment module, open the second switch valve, close the regulating valve connecting the liquid replenishment module and the supply module pipeline, briefly start the first heating device, and determine the liquid refrigerant content in the liquid replenishment tank according to the power consumption-liquid quantity relationship;

[0042] b) Start the second heating device briefly and determine the liquid refrigerant content in the supply tank based on the power consumption-liquid volume relationship;

[0043] c) If the liquid refrigerant content in both the first and second liquid replenishment modules is less than the set lower limit, an alarm will be triggered, and the compressor will be prohibited from starting; otherwise, the liquid replenishment tank with the higher liquid refrigerant content will be designated as the working tank; if the liquid refrigerant content in the working tank exceeds the set upper limit, the tank will be heated to the set temperature and then the second switch valve will be closed, and the tank will continue to be heated to the set pressure; if the liquid refrigerant content in the working tank is lower than the set upper limit, the second switch valve will be closed, and the tank will continue to be heated to the set pressure.

[0044] d) If the liquid refrigerant content in the supply tank of the supply module is less than the set lower limit, open the regulating valve between the supply tank and the working tank to supply liquid refrigerant to the supply tank; repeat steps a) to d) until the liquid refrigerant content in the supply tank reaches the set lower limit.

[0045] e) If the liquid refrigerant content in the supply module's liquid tank is greater than the set lower limit, then close the regulating valve, start the second heating device to the set pressure, and start the compressor.

[0046] According to at least one embodiment of the fluid supply method for a compressor of the present disclosure, when the compressor is in normal operation, supplying liquid refrigerant to the supply module includes the following steps:

[0047] f) Wait for the liquid dispensing request from the supply module. Upon receiving the request, execute steps g) to j).

[0048] g) For the working tank, the first heating device is started briefly, and the content of the remaining liquid refrigerant in the replenishment tank is determined according to the power consumption-liquid volume relationship; the filling time is obtained according to the content of the remaining liquid refrigerant; the second switch valve is opened, then the first switch valve is opened, and after a predetermined time, the first switch valve and the second switch valve are closed, and the electric heater is started briefly, and the content of the liquid refrigerant in the replenishment tank is determined according to the power consumption-liquid volume relationship.

[0049] h) For non-working tanks, obtain the filling time based on the previously measured liquid refrigerant content, open the first switch valve, or open the first switch valve and the second switch valve, and close the first switch valve and the second switch valve after a predetermined time; briefly start the electric heater, and determine the liquid refrigerant content in the replenishment tank based on the power consumption-liquid volume relationship;

[0050] i) If the liquid refrigerant content in the working tank exceeds the set upper limit, open the second switch valve of the working tank, continue heating to the set temperature, then close the second switch valve of the working tank, and continue heating to the set pressure; if the liquid refrigerant content in the working tank is lower than the set upper limit, close the second switch valve of the working tank, continue heating to the set pressure, and open the second switch valve of the non-working tank.

[0051] j) Open the regulating valve between the supply tank and the working tank to supply liquid refrigerant to the supply tank; close the regulating valve after the pressure of the working tank and the supply tank is balanced.

[0052] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, when the pressure of the liquid supply tank is lower than a set lower limit, a second heating device is activated to increase the pressure in the liquid supply tank, and the liquid refrigerant content in the liquid supply tank is calculated; when the liquid refrigerant content in the liquid supply tank is lower than a set lower limit, a liquid extraction request is issued.

[0053] According to at least one embodiment of the fluid supply method for a compressor disclosed herein, when the pressure in the supply tank exceeds a set upper limit, a regulating valve between the supply tank and the non-working tank is opened to reduce the pressure in the supply tank. Attached Figure Description

[0054] The accompanying drawings illustrate exemplary embodiments of the present disclosure and, together with the description thereof, serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0055] Figure 1 This is a schematic diagram of a fluid supply system for a compressor according to one embodiment of the present disclosure.

[0056] Figure 2 This is a schematic diagram of a fluid supply system for a compressor according to one embodiment of the present disclosure.

[0057] Figure 3 This is a schematic diagram of a fluid supply system for a compressor according to one embodiment of the present disclosure.

[0058] Figure 4 This is a schematic diagram illustrating the relationship between the electric heating power consumption per unit temperature rise of the refrigerant in the tank and the percentage of liquid refrigerant in the tank volume according to one embodiment of this disclosure.

[0059] The specific labels in the attached figures are as follows:

[0060] 100 replenishment tank

[0061] 120 First Heating Device

[0062] 140 First Pressure Sensor

[0063] 200 First switching valve (liquid enters valve body)

[0064] 300 Second Switch Valve (Gas Passage)

[0065] 400 regulating valve

[0066] 600 supply tanks

[0067] 620 Second Heating Device

[0068] 640 Second Pressure Sensor

[0069] 800 filter. Detailed Implementation

[0070] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the disclosure. Furthermore, it should be noted that, for ease of description, only the parts relevant to the present disclosure are shown in the accompanying drawings.

[0071] It should be noted that, where there is no conflict, the embodiments and features described in this disclosure can be combined with each other. The technical solutions of this disclosure will now be described in detail with reference to the accompanying drawings and embodiments.

[0072] Unless otherwise stated, the exemplary implementations / embodiments shown are to be understood as providing exemplary features of various details that provide ways in which the technical concepts of this disclosure can be implemented in practice. Therefore, unless otherwise stated, the features of various implementations / embodiments may be additionally combined, separated, interchanged and / or rearranged without departing from the technical concepts of this disclosure.

[0073] The use of crosshairs and / or shading in the accompanying drawings is generally used to clarify the boundaries between adjacent components. Thus, unless otherwise stated, the presence or absence of crosshairs or shading does not convey or indicate any preference or requirement for the specific material, material properties, dimensions, proportions, commonalities between the illustrated components, or any other characteristics, properties, etc., of the components. Furthermore, in the accompanying drawings, the dimensions and relative dimensions of components may be exaggerated for clarity and / or descriptive purposes. When exemplary embodiments can be implemented differently, a specific process sequence may be performed in a different order than that described. For example, two consecutively described processes may be performed substantially simultaneously or in the reverse order of their description. Furthermore, the same reference numerals denote the same components.

[0074] When a component is referred to as being "on" or "above" another component, "connected to," or "joined to" another component, the component may be directly on, directly connected to, or directly joined to the other component, or there may be intermediate components. However, when a component is referred to as being "directly on" another component, "directly connected to," or "directly joined to" another component, there are no intermediate components. Therefore, the term "connection" can refer to a physical connection, an electrical connection, etc., and may or may not have intermediate components.

[0075] For descriptive purposes, this disclosure may use spatial relative terms such as “below,” “under,” “below,” “down,” “above,” “above,” “higher,” and “side (e.g., in a “sidewall”)” to describe the relationship between one component and another component as shown in the accompanying drawings. In addition to the orientations depicted in the drawings, the spatial relative terms are also intended to encompass different orientations of the device during use, operation, and / or manufacture. For example, if the device in the drawings is flipped, a component described as “below” or “under” another component or feature would subsequently be positioned “above” said other component or feature. Thus, the exemplary term “below” can encompass both “above” and “below” orientations. Furthermore, the device may be otherwise positioned (e.g., rotated 90 degrees or in other orientations), thus interpreting the spatial relative descriptive terms used herein accordingly.

[0076] The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms “a” and “the” are intended to include the plural forms as well. Furthermore, when the terms “comprising” and / or “including” and variations thereof are used in this specification, it indicates the presence of the stated features, integrals, steps, operations, parts, components, and / or groups thereof, but does not exclude the presence or addition of one or more other features, integrals, steps, operations, parts, components, and / or groups thereof. It should also be noted that, as used herein, the terms “substantially,” “about,” and other similar terms are used as approximate terms rather than as terms of degree, thus explaining the inherent biases in measurements, calculated values, and / or provided values ​​that would be recognized by one of ordinary skill in the art.

[0077] Figure 2 This is a schematic diagram of a fluid supply system for a compressor according to one embodiment of the present disclosure. Figure 3 This is a schematic diagram of a fluid supply system for a compressor according to one embodiment of the present disclosure.

[0078] like Figure 2 and Figure 3 As shown, the fluid supply system for compressors provided in this disclosure can be applied to refrigeration units.

[0079] In a typical embodiment, the refrigeration unit includes a compressor unit, which includes a motor and a compressor driven by the motor. The compressor unit includes static pressure air bearings, which may include axial static pressure air bearings and radial static pressure air bearings. The fluid supply system for the compressor is capable of supplying air to the aforementioned axial and radial static pressure air bearings. The structure of the compressor unit is a common structure in the prior art and will not be described in detail here. Those skilled in the art should understand that the compressor unit can be a multi-stage compressor unit, which is also quite common in the art. The structure of such a multi-stage compressor unit will also not be described in detail here.

[0080] The compressor unit is connected to the condenser to cool the high-temperature, high-pressure gaseous refrigerant output by the compressor unit into a liquid refrigerant. That is, the condenser includes liquid refrigerant. In one embodiment, the liquid refrigerant is located in the lower middle part of the condenser.

[0081] The condenser is connected to the evaporator via an expansion valve. The expansion valve is used to reduce the pressure of the liquid refrigerant in the condenser to produce a mixture of low-temperature, low-pressure gaseous and liquid refrigerant. The liquid refrigerant, after being depressurized by the expansion valve, enters the evaporator, where it vaporizes and allows the evaporator to absorb a large amount of heat.

[0082] The low-temperature, low-pressure gaseous refrigerant produced by the evaporator is transported to the compressor unit, where it is compressed to produce a high-temperature, high-pressure gaseous refrigerant.

[0083] Those skilled in the art should know that when a refrigeration unit includes components such as an economizer (flash tank), the economizer is connected to the condenser and the evaporator.

[0084] In other words, in a refrigeration unit, the condenser, evaporator, and economizer all contain liquid refrigerant, and correspondingly, the liquid storage device disclosed herein includes at least one of the evaporator, condenser, and economizer.

[0085] The fluid supply system for the compressor includes at least a replenishment module and a supply module.

[0086] The liquid replenishment module receives liquid refrigerant by gravity in the liquid storage device; the supply module receives liquid refrigerant and / or gaseous refrigerant provided by the liquid replenishment module according to the pressure difference between the supply module and the liquid replenishment module; and the supply module provides liquid refrigerant and / or gaseous refrigerant to the hydrostatic air bearing.

[0087] In one embodiment, the number of the liquid replenishment module can be one, two, or three, etc. When there is only one liquid replenishment module, it can be connected to any one of the condenser, evaporator, and economizer. Preferably, considering that the temperature of the liquid refrigerant in the condenser is relatively high, the liquid replenishment module is preferentially connected to the condenser, and the condenser supplies liquid refrigerant to the liquid replenishment module.

[0088] In another embodiment, when there are two liquid replenishment modules, the two liquid replenishment modules can be connected to two of the condenser, evaporator and economizer respectively; preferably, the two liquid replenishment modules can be connected to the condenser and evaporator respectively, or connected to the condenser and economizer, so that the condenser, evaporator and economizer can supply liquid refrigerant to the liquid replenishment modules individually, or supply liquid refrigerant to different liquid replenishment modules simultaneously.

[0089] In the third embodiment, the number of liquid replenishment modules is three. In this case, the three liquid replenishment modules are respectively connected to the condenser, evaporator and economizer. Accordingly, the condenser, evaporator and economizer can supply liquid refrigerant to the liquid replenishment modules individually, or they can supply liquid refrigerant to different liquid replenishment modules at the same time.

[0090] In this disclosure, a regulating valve 400 is provided between the replenishment module and the supply module. In one embodiment, when there are multiple replenishment modules (e.g., two or more), all replenishment modules are connected to the same supply module. Of course, those skilled in the art should understand that the replenishment modules and supply modules can be configured in a one-to-one correspondence. Alternatively, one replenishment module can be connected to multiple supply modules. Or, multiple replenishment modules can be connected to the same supply module.

[0091] The following is a detailed description of the structure of the fluid replenishment module.

[0092] The liquid replenishment module includes a liquid replenishment tank 100, which is connected to the liquid storage device via a first pipeline. A first switching valve 200 is installed on the first pipeline, and liquid refrigerant enters the liquid replenishment tank 100 through the first pipeline. Positionally, the liquid replenishment tank 100 is located at the lower part of the liquid storage device, allowing the liquid refrigerant in the liquid storage device to flow into the liquid replenishment tank 100 under gravity.

[0093] Preferably, the connection between the first pipeline and the liquid storage device is located at the lower part or bottom of the liquid storage device, so that the first pipeline can conveniently output liquid refrigerant from the liquid storage device; correspondingly, the connection between the first pipeline and the replenishment tank 100 is located in the lower middle part of the replenishment tank 100.

[0094] The replenishment tank 100 is also connected to the liquid storage device via a second pipeline, wherein the second pipeline is equipped with a second switching valve 300 to facilitate fluid interaction between the liquid storage device and the replenishment tank 100. In this disclosure, the liquid storage device and the replenishment tank 100 exchange gaseous refrigerant via the second pipeline, thereby enabling the gas pressure between the liquid storage device and the replenishment tank 100 to be balanced. In other words, the second pipeline allows the gas in the replenishment tank to flow to the delivery device. Positionally, the connection point between the second pipeline and the liquid storage device is located at the upper or top of the liquid storage device; correspondingly, the connection point between the second pipeline and the replenishment tank 100 is also located at the upper / top of the replenishment tank 100.

[0095] In this disclosure, the liquid replenishment module includes a first heating device 120, which is disposed inside the liquid replenishment tank 100. The first heating device 120 provides heat to the liquid refrigerant inside the liquid replenishment tank 100, i.e., heats the liquid refrigerant, causing it to vaporize and generate gaseous refrigerant, thereby increasing the gas pressure inside the liquid replenishment tank 100. In a preferred embodiment, the first heating device 120 can be an electric heating device.

[0096] More preferably, the replenishment module further includes a first pressure sensor 140, which can be disposed in the replenishment tank 100 to obtain the pressure of the gaseous refrigerant in the replenishment tank 100. In this disclosure, the first switching valve 200, the second switching valve 300 and the regulating valve 400 can be controlled according to the pressure of the gaseous refrigerant detected by the first pressure sensor 140 to realize the operation of the fluid supply system for the compressor.

[0097] In a preferred embodiment, the number of liquid replenishment modules is two, or the liquid replenishment modules include a first liquid replenishment module and a second liquid replenishment module. The first liquid replenishment module is connected to the condenser to receive liquid refrigerant from the condenser, and thus the first liquid replenishment module can also be called the condenser liquid replenishment module. Correspondingly, the second liquid replenishment module is connected to the evaporator or economizer to receive liquid refrigerant from the evaporator or economizer, and thus the second liquid replenishment module can also be called the evaporator liquid replenishment module.

[0098] The connection methods between the first liquid replenishment module and the condenser, and between the second liquid replenishment module and the evaporator or economizer, have been explained in detail above and will not be repeated here.

[0099] The following provides a detailed explanation of the structure of the supply module.

[0100] The supply module includes a supply tank 600 connected to the replenishment module and the hydrostatic air bearing. For example, the supply tank 600 is connected to the replenishment tank 100, thereby enabling the receipt of liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant from the replenishment tank 100. Conversely, the supply tank 600 is also connected to the hydrostatic air bearing and is capable of supplying liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant to the hydrostatic air bearing, allowing the hydrostatic air bearing to support the shaft by the liquid and gaseous refrigerant. Positionally, the replenishment module is higher than the supply module.

[0101] In this disclosure, considering the low pressure of the liquid and / or gaseous refrigerant output from the hydrostatic air bearing, these liquid and / or gaseous refrigerants, mainly gaseous refrigerants, are delivered to the evaporator (inlet of the compressor unit).

[0102] In this disclosure, the supply module includes a second heating device 620 disposed within the supply tank 600. The second heating device 620 provides heat to the liquid refrigerant within the supply tank 600, heating the liquid refrigerant and causing it to vaporize, producing gaseous refrigerant and increasing the gas pressure within the supply tank 600. In a preferred embodiment, the second heating device 620 may be an electric heating device.

[0103] More preferably, the supply module further includes a second pressure sensor 640, which can be disposed in the supply tank 600 to obtain the pressure of the gaseous refrigerant in the supply tank 600. In this disclosure, the first switching valve 200, the second switching valve 300 and the regulating valve 400 can be controlled according to the pressure of the gaseous refrigerant detected by the second pressure sensor 640 to realize the operation of the fluid supply system for the compressor.

[0104] In this disclosure, the supply tank 600 is connected to a drain pipe (not shown in the figure), and the drain pipe is equipped with a pressure relief valve. The pressure relief valve can open or close the drain pipe, thereby preventing the gaseous refrigerant in the supply tank 600 from becoming too high and improving the safety of the fluid supply system used for the compressor.

[0105] In one embodiment, the drain pipe can be connected to either the evaporator (the inlet of the compressor unit) or the condenser (the outlet of the compressor unit).

[0106] In this disclosure, a supply pipeline is provided between the supply tank 600 and the static pressure air bearing, and a filter 800 is provided on the supply pipeline to prevent impurities in the liquid refrigerant and gaseous refrigerant from damaging components such as the static pressure air bearing.

[0107] Based on the above structural description of this disclosure, the fluid supply system for the compressor of this disclosure does not include a pump, or rather, does not include a pump body for conveying liquid refrigerant, thereby effectively solving the technical problem of refrigerant pump damage.

[0108] On the other hand, based on the above structural description of this disclosure, the fluid supply system for the compressor of this disclosure does not include a liquid level sensor. That is, since this disclosure has a first heating device 120 and a first pressure sensor 140, as well as a second heating device 620 and a second pressure sensor 640, the amount of liquid refrigerant in the replenishment tank 100 and the supply tank 600 can be calculated by the relationship between the heating time of the heater and the pressure detected by the pressure sensor. This avoids the use of expensive level gauges, and the fluid supply system for the compressor reduces the cost by 80% compared to the equipment in the prior art, and greatly improves the market competitiveness of the product.

[0109] According to another aspect of this disclosure, a fluid supply method for a compressor is provided, comprising a replenishment mode and a supply mode; wherein: the replenishment mode is a process of transferring liquid refrigerant from a liquid storage device to a fluid supply system for a hydrostatic air bearing, and the supply mode is a process of supplying liquid refrigerant and / or gaseous refrigerant to the hydrostatic air bearing.

[0110] Preferably, the fluid supply method for the hydrostatic air bearing can be implemented using the fluid supply device for the hydrostatic air bearing described above. The structure of this fluid supply device for the hydrostatic air bearing will not be detailed here.

[0111] In this disclosure, the replenishment mode includes: controlling the second switching valve 300 to make the pressure of the gaseous refrigerant in the replenishment module and the liquid storage device the same; controlling the first switching valve 200 to make the liquid refrigerant in the liquid storage device flow to the replenishment module under the action of gravity; controlling the replenishment module to increase the pressure of the gaseous refrigerant in the replenishment module; and controlling the regulating valve 400 to make the liquid refrigerant and / or gaseous refrigerant in the replenishment module flow to the supply module.

[0112] Accordingly, the supply mode includes: controlling the supply module to supply liquid refrigerant and / or gaseous refrigerant to the hydrostatic air bearing.

[0113] Specifically, when replenishing the liquid, the regulating valve 400 is first closed, meaning that the replenishment module and the supply module are not connected at this time.

[0114] Then, the second switch valve 300 is opened to allow gas communication between the replenishment module and the storage device. For example, the replenishment tank 100 and the storage device are connected by gas, and at this time, the pressure of the gaseous refrigerant in the replenishment tank 100 and the storage device is the same.

[0115] Next, the first switch valve 200 is opened. At this time, the liquid refrigerant in the liquid storage device will flow into the replenishment tank 100 under the action of gravity. After a set time, the first switch valve 200 and the second switch valve 300 are closed.

[0116] Then, heat is supplied to the replenishment tank 100, for example, to heat the liquid refrigerant inside the replenishment tank 100, causing some of the liquid refrigerant to vaporize and form gaseous refrigerant. At this time, the gas pressure inside the replenishment tank 100 will increase; the pressure of the gaseous refrigerant inside the replenishment tank 100 is detected by the first pressure sensor 140. When the pressure of the gaseous refrigerant inside the replenishment tank 100 is greater than or equal to a set value, the first heating device 120 is turned off.

[0117] Open the regulating valve 400 to allow the liquid refrigerant and / or gaseous refrigerant in the replenishment tank 100 to flow into the supply tank 600. In one embodiment, the replenishment tank 100 is connected to the supply tank 600 via a replenishment pipeline, in which case the regulating valve 400 is located in the replenishment pipeline; moreover, the connection point between the replenishment pipeline and the replenishment tank 100 is located in the lower middle part of the replenishment tank 100, thereby enabling the majority or all of the liquid refrigerant in the replenishment tank 100 to be forced into the supply tank 600.

[0118] In other words, while the liquid refrigerant in the storage device flows to the replenishment module, the regulating valve 400 remains closed; correspondingly, when the regulating valve 400 opens, the replenishment tank 100 replenishes the supply tank 600; furthermore, the pressure fluctuation in the supply tank 600 can be kept within a set range by controlling the opening degree of the regulating valve 400. When the pressure difference between the replenishment tank 100 and the supply tank 600 (pressure difference value) decreases to a set value, the regulating valve 400 is closed; the supply mode can then be executed again.

[0119] Accordingly, in the supply tank 600, the pressure of the gaseous refrigerant in the supply tank 600 can be increased by providing heat to the liquid refrigerant in the supply tank 600, for example by heating the liquid refrigerant through the second heating device 620. Correspondingly, the pressure of the gaseous refrigerant in the supply tank 600 is detected by the second pressure sensor 640. When the pressure of the gaseous refrigerant in the supply tank 600 is greater than or equal to a preset value, the supply tank 600 can supply liquid refrigerant and / or gaseous refrigerant to the hydrostatic air bearing.

[0120] That is, the regulating valve 400 is preferably in the closed state while the supply tank 600 supplies liquid refrigerant and / or gaseous refrigerant to the static pressure air bearing.

[0121] According to another key point of this disclosure, the amount of liquid refrigerant (the height of the liquid refrigerant or the liquid surface position of the liquid refrigerant) in the replenishment tank 100 or supply tank 600 is obtained by calculation, thereby eliminating the need for expensive level gauges.

[0122] In one embodiment, the volume of liquid refrigerant in the tank can be determined by the relationship between the electric heating power consumption per unit temperature rise of the refrigerant in the tank and the percentage of liquid refrigerant in the tank volume; this "relationship between the electric heating power consumption per unit temperature rise of the refrigerant in the tank and the percentage of liquid refrigerant in the tank volume (referred to as the power consumption-liquid volume relationship)" is as follows: Figure 4 As shown.

[0123] Specifically, before using the fluid supply system for the compressor, the time required for the replenishment tank to fill with liquid refrigerant under gravity, the electric heating power consumption per unit temperature rise when the liquid refrigerant fills the replenishment tank, and the electric heating power consumption per unit temperature rise when the liquid refrigerant fills the supply tank are measured and recorded in advance. Based on these measurements, the content of liquid refrigerant in the replenishment tank and / or supply tank is obtained and controlled.

[0124] Accordingly, if the liquid refrigerant level in the replenishment tank 100 is lower than the set value, the replenishment tank 100 will be marked as empty, and the replenishment module will be temporarily suspended. During the next replenishment cycle, the module will be replenished, and its operating status will be updated based on the liquid refrigerant level in the replenishment tank 100 being greater than or equal to the set value, at which point the replenishment module will be reused.

[0125] Similarly, when the liquid refrigerant level in all liquid replenishment tanks 100 is lower than the set value, all liquid replenishment tanks 100 are marked as empty, the compressor unit stops working and an alarm is triggered.

[0126] Furthermore, when the liquid refrigerant level in all the replenishment tanks 100 is greater than or equal to the set value, the replenishment module connected to the condenser is used first to supply liquid refrigerant and / or gaseous refrigerant to the supply module. At this time, since the saturation pressure of the condenser is higher than that of the evaporator, the power consumption for heating and pressurizing is lower.

[0127] Similarly, there is no level gauge in the supply tank 600. The relationship between the electric heating power consumption per unit temperature rise and the percentage of liquid refrigerant in the tank volume can be obtained by experimentation. The liquid level of the liquid refrigerant in the supply tank 600 can be obtained by looking up a table or by calculation.

[0128] In this disclosure, the volume of the supply tank 600 is larger than that of the replenishment tank 100. That is to say, the time required for the pressure in the supply tank 600 to drop to the lower limit is greater than the time required for the liquid refrigerant filling process and heating process of any replenishment module, thereby enabling the compressor unit to operate stably.

[0129] In an extreme case, when the pressure of the gaseous refrigerant in the supply tank 600 is less than the preset value, and all the replenishment tanks 100 are not in a liquid state, the second heating device 620 is activated to maintain the pressure in the supply tank 600 for a short time, and the compressor unit stops and alarms.

[0130] During the start-up preparation phase of the refrigeration unit, the liquid replenishment mode shall be executed at least once to ensure that the amount of liquid refrigerant in the liquid replenishment tank 100 and / or the supply tank 600 meets the requirements.

[0131] When the evaporator pressure drops, the pressure difference at the static pressure air bearing increases. This opens the regulating valve 400 and / or the second switching valve 300 to allow liquid and / or gaseous refrigerant in the supply tank 600 to flow to the supply tank 600, thus maintaining a constant pressure difference at the static pressure air bearing. Alternatively, the pressure relief valve 700 can be opened to release pressure and maintain a constant pressure difference at the static pressure air bearing.

[0132] When the pressure of the evaporator rises, the pressure difference at the static pressure air bearing decreases accordingly. Then, the first heating device 120 of the liquid replenishment module or the second heating device 620 of the supply module is activated to increase the pressure of the liquid replenishment tank 100 and / or the supply tank 600, so as to maintain a stable pressure difference at the static pressure air bearing.

[0133] Specifically, in the fluid supply method for a compressor disclosed herein, when the compressor is started (or the refrigeration unit is started), it includes the following steps:

[0134] a) Close the first switch valve 200 of the replenishment module, open the second switch valve 300, close the regulating valve 400 connecting the pipeline of the replenishment module and the supply module, briefly start the first heating device (electric heater), and determine the liquid refrigerant content in the replenishment tank according to the power consumption-liquid volume relationship;

[0135] b) Short-term start-up of the second heating device (electric heater), and determination of the liquid refrigerant content in the supply tank based on the power consumption-liquid volume relationship;

[0136] c) If the liquid refrigerant content in both the first and second liquid replenishment modules is less than the set lower limit, an alarm will be triggered, and the compressor will be prohibited from starting; otherwise, the liquid replenishment tank with the higher liquid refrigerant content will be designated as the working tank; if the liquid refrigerant content in the working tank exceeds the set upper limit, the tank will be heated to the set temperature and then the second switch valve will be closed, and the tank will continue to be heated to the set pressure; if the liquid refrigerant content in the working tank is lower than the set upper limit, the second switch valve will be closed, and the tank will continue to be heated to the set pressure.

[0137] d) If the liquid refrigerant content in the supply tank of the supply module is less than the set lower limit, open the regulating valve between the supply tank and the working tank to supply liquid refrigerant to the supply tank; repeat steps a) to d) until the liquid refrigerant content in the supply tank reaches the set lower limit.

[0138] e) If the liquid refrigerant content in the supply module's liquid tank is greater than the set lower limit, then close the regulating valve, start the second heating device (heater) to the set pressure, and start the compressor.

[0139] Furthermore, the fluid supply method for a compressor disclosed herein also includes: when the compressor is in normal operation, supplying liquid refrigerant to the supply module includes the following steps:

[0140] f) Wait for the liquid dispensing request from the supply module. Upon receiving the request, execute steps g) to j).

[0141] g) For the working tank, start the electric heater briefly, determine the remaining liquid refrigerant content in the replenishment tank based on the power consumption-liquid volume relationship; obtain the filling time based on the remaining liquid refrigerant content; open the second switch valve, then open the first switch valve, and after a predetermined time (less than or equal to the filling time), close the first and second switch valves, start the electric heater briefly, and determine the liquid refrigerant content in the replenishment tank based on the power consumption-liquid volume relationship.

[0142] h) For non-working tanks, based on the previously measured liquid content, determine the filling time, open the first switching valve, or open both the first and second switching valves, and close both valves after a predetermined time (less than or equal to the filling time). Briefly start the electric heater, and determine the liquid refrigerant content in the replenishment tank based on the power consumption-liquid volume relationship.

[0143] i) If the liquid refrigerant content in both the condenser and evaporator refrigerant supply modules is below the set lower limit, an alarm will sound, forcing the compressor to stop; otherwise, the supply tank with the higher liquid refrigerant content will be designated as the working tank. If the liquid content in the working tank exceeds the set upper limit, the second switch valve will be opened, and heating will continue until the set temperature is reached, then the second switch valve will be closed, and heating will continue until the set pressure is reached. If the liquid content in the working tank is below the set upper limit, the second switch valve will be closed, and heating will continue until the set pressure is reached. The second switch valve of the non-working tank will be opened.

[0144] j) Open the regulating valve between the supply tank and the working tank to supply liquid refrigerant to the supply tank; close the regulating valve after the pressure of the working tank and the supply tank is balanced.

[0145] In one specific embodiment, when the pressure in the supply tank is lower than the set lower limit, the electric heater is activated to increase the pressure inside the tank, and the liquid refrigerant content in the tank is calculated; when the liquid refrigerant content in the tank is lower than the set lower limit, a liquid extraction request is issued.

[0146] In a preferred embodiment, when the pressure in the supply tank exceeds a set upper limit, the regulating valve between the supply tank and the non-working tank is opened to reduce the pressure in the supply tank.

[0147] In the description of this specification, the references to terms such as "one embodiment / mode," "some embodiments / modes," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment / mode or example is included in at least one embodiment / mode or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment / mode or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments / modes or examples. Furthermore, without contradiction, those skilled in the art can combine and integrate the different embodiments / modes or examples described in this specification, as well as the features of different embodiments / modes or examples.

[0148] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0149] Those skilled in the art should understand that the above embodiments are merely for illustrating the present disclosure and are not intended to limit the scope of the disclosure. Those skilled in the art can make other changes or modifications based on the above disclosure, and these changes or modifications still fall within the scope of the present disclosure.

Claims

1. A fluid supply method for a fluid supply system of a compressor, characterized in that, The fluid supply system is applied to a refrigeration unit, which includes at least a liquid storage device. The fluid supply system includes a replenishment module and a supply module. The replenishment module receives liquid refrigerant by gravity in the liquid storage device. The supply module receives liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant from the replenishment module based on the pressure difference between the supply module and the replenishment module; and the supply module provides liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant to the hydrostatic air bearing used in the compressor; wherein, the replenishment module further includes a first replenishment module and a second replenishment module, the first replenishment module and the second replenishment module being connected to different liquid storage devices; The fluid supply method includes: a replenishment mode and a supply mode; wherein: The fluid replacement modes include: Control the second switching valve to make the pressure of the gaseous refrigerant in the liquid replenishment module and the liquid storage device the same; Control the first switching valve so that the liquid refrigerant in the liquid storage device flows to the liquid replenishment module under the action of gravity; Control the liquid replenishment module to increase the pressure of the gaseous refrigerant within it; and Control the regulating valve to allow the liquid refrigerant and / or gaseous refrigerant in the replenishment module to flow to the supply module; The supply modes include: Control the supply module so that it supplies liquid refrigerant and / or gaseous refrigerant and / or a mixture of liquid and gaseous refrigerant to the hydrostatic air bearing; The process of starting the compressor includes the following steps: a) Close the first switch valve of the liquid replenishment module, open the second switch valve, close the regulating valve connecting the liquid replenishment module and the supply module pipeline, briefly start the first heating device in the liquid replenishment tank of the liquid replenishment module, and determine the liquid refrigerant content in the liquid replenishment tank according to the power consumption-liquid quantity relationship; b) The second heating device in the liquid supply tank of the short-term start-up supply module determines the liquid refrigerant content in the liquid supply tank based on the power consumption-liquid quantity relationship; c) If the liquid refrigerant content in both the first and second liquid replenishment modules is less than the set lower limit, an alarm will be triggered, and the compressor will be prohibited from starting; otherwise, the liquid replenishment tank with the higher liquid refrigerant content will be designated as the working tank; if the liquid refrigerant content in the working tank exceeds the set upper limit, the tank will be continuously heated to the set temperature and then the second switch valve will be closed, and the tank will continue to be heated to the set pressure; if the liquid refrigerant content in the working tank is lower than the set upper limit, the second switch valve will be closed, and the tank will continue to be heated to the set pressure. d) If the liquid refrigerant content in the supply tank of the supply module is less than the set lower limit, open the regulating valve between the supply tank and the working tank to supply liquid refrigerant to the supply tank; repeat steps a) to d) until the liquid refrigerant content in the supply tank reaches the set lower limit. e) If the liquid refrigerant content in the supply module's liquid tank is greater than the set lower limit, close the regulating valve, start the second heating device to the set pressure, and start the compressor; When the compressor is in normal operation, supplying liquid refrigerant to the supply module includes the following steps: f) Wait for the supply module to request liquid intake; upon receiving the request, execute steps g) to j). g) For the working tank, the first heating device is started briefly, and the content of the remaining liquid refrigerant in the replenishment tank is determined according to the power consumption-liquid volume relationship; the filling time is obtained according to the content of the remaining liquid refrigerant; the second switch valve is opened, then the first switch valve is opened, and after a predetermined time, the first switch valve and the second switch valve are closed, the first heating device is started briefly, and the content of the liquid refrigerant in the replenishment tank is determined according to the power consumption-liquid volume relationship. h) For non-working tanks, obtain the filling time based on the previously measured liquid refrigerant content, open the first switch valve, or open the first switch valve and the second switch valve, and close the first switch valve and the second switch valve after a predetermined time; briefly start the first heating device, and determine the liquid refrigerant content in the replenishment tank based on the power consumption-liquid volume relationship; i) If the liquid refrigerant content in the working tank exceeds the set upper limit, open the second switch valve of the working tank, continue heating to the set temperature, then close the second switch valve of the working tank, and continue heating to the set pressure; if the liquid refrigerant content in the working tank is lower than the set upper limit, close the second switch valve of the working tank, continue heating to the set pressure, and open the second switch valve of the non-working tank. j) Open the regulating valve between the supply tank and the working tank to supply liquid refrigerant to the supply tank; close the regulating valve after the pressure of the working tank and the supply tank is balanced.

2. The fluid supply method for a compressor as described in claim 1, characterized in that, During the flow of liquid refrigerant and / or gaseous refrigerant from the replenishment module to the supply module, the opening of the regulating valve is controlled so that pressure fluctuations within the supply module remain within a set range.

3. The fluid supply method for a compressor as described in claim 1, characterized in that, During the flow of liquid refrigerant and / or gaseous refrigerant from the replenishment module to the supply module, the regulating valve is closed when the pressure difference between the replenishment module and the supply module decreases to a set value.

4. The fluid supply method for a compressor as described in claim 3, characterized in that, When the regulating valve is closed, liquid refrigerant is supplied to the liquid replenishment module.

5. The fluid supply method for a compressor as described in claim 1, characterized in that, By heating the liquid refrigerant in the replenishment module, the pressure of the gaseous refrigerant in the replenishment module is increased.

6. The fluid supply method for a compressor as described in claim 1, characterized in that, The amount of residual liquid refrigerant in the replenishment module and / or supply module is determined based on the power consumption-liquid volume relationship.

7. The fluid supply method for a compressor as described in claim 1, characterized in that, During the start-up preparation phase of the refrigeration unit, the liquid replenishment mode should be executed at least once.

8. The fluid supply method for a compressor as described in claim 1, characterized in that, The regulating valve remains closed while the liquid refrigerant in the storage device flows to the replenishment module.

9. The fluid supply method for a compressor as described in claim 1, characterized in that, When the pressure in the liquid supply tank is lower than the set lower limit, the second heating device is activated to increase the pressure in the liquid supply tank and the liquid refrigerant content in the liquid supply tank is calculated; when the liquid refrigerant content in the liquid supply tank is lower than the set lower limit, a liquid extraction request is issued.

10. The fluid supply method for a compressor as described in claim 1, characterized in that, When the pressure in the supply tank exceeds the set upper limit, the regulating valve between the supply tank and the non-working tank is opened to reduce the pressure in the supply tank.

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