Bearing gas supply system and bearing gas supply control method for an air bearing compressor

Abstract

The application discloses a bearing gas supply system and a bearing gas supply control method of an aerostatic compressor. The system comprises: a compressor gas supply circuit connected between an evaporator and the aerostatic compressor, and supplying gas to the bearing of the aerostatic compressor through a gas compressor; a condenser gas supply circuit connected between a condenser, the aerostatic compressor and the evaporator, and supplying gas to the bearing through the condenser; the compressor gas supply circuit and the condenser gas supply circuit have a common part, and the common part comprises a gas supply tank; a cooling circuit for heat exchange of the gas supplied to the bearing by the gas compressor or the condenser, so that the gas supply temperature is stabilized at a target gas supply temperature; and a gas supply pressure stabilizing pipeline connected between the gas supply tank and the evaporator, and used for adjusting the pressure of the gas supply tank, so that the gas supply pressure difference is stabilized at a target gas supply pressure difference. Through cooperation of the gas supply, pressure stabilizing and cooling circuits, the application provides a stable gas supply pressure difference, ensures appropriate gas supply temperature, and solves the problems of unstable gas supply pressure difference and high gas supply temperature of the aerostatic bearing.

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and more specifically, to a bearing air supply system and bearing air supply control method for an air-suspension compressor. Background Technology

[0002] Centrifugal chillers are commonly used in various building air conditioning systems. Currently, the compressor bearings of centrifugal chillers mainly use oil-lubricated bearings and magnetic levitation bearings. In recent years, gas bearings, also known as air suspension bearings, have also become popular.

[0003] Air bearings utilize gas force to support the rotating shaft, offering the following advantages: 1) Compared to compressors using oil-lubricated bearings, they eliminate the need for oil supply, return, and cooling systems, thus eliminating the risk of lubricant leakage and saving on lubrication maintenance. During operation, the bearing is suspended, resulting in no friction, reducing mechanical losses and improving unit performance; 2) Compared to compressors using magnetic bearings, they eliminate the need for complex electrical control systems and abnormal power failure protection systems, and the bearing size is relatively smaller.

[0004] Air bearings utilize gas force to support the rotating shaft. To ensure the normal operation of air bearings, a reliable and stable air supply system is required. Currently, common air supply methods include using refrigerant pumps, electric heating, air tanks, or air compressors.

[0005] The system employs a refrigerant pump, electric heating, and a gas storage tank. First, the refrigerant pump supplies liquid refrigerant to the gas storage tank. Then, the electric heating pressurizes the refrigerant in the tank to meet the required pressure before supplying it to the bearings. This solution has the following drawbacks: To ensure the supply pressure remains within the appropriate range, the electric heater needs to be periodically turned on and off. This periodic fluctuation in supply pressure is detrimental to stable bearing operation. Furthermore, frequent start-stop cycles shorten the electric heater's lifespan. To prevent the electric heater from dry-burning, a level sensor is needed to measure the refrigerant level in the gas storage tank, ensuring sufficient refrigerant before activating the electric heater, thus increasing unit costs.

[0006] The gas is supplied by a gas compressor, which has high gas pressure and high gas temperature. High temperature affects the reliability of the bearing and may even lead to bearing damage.

[0007] There is currently no effective solution to the problems of unstable bearing air supply pressure difference and high air supply temperature in existing air suspension compressors. Summary of the Invention

[0008] This invention provides a bearing air supply system and bearing air supply control method for an air-suspension compressor, which at least solves the problems of unstable bearing air supply pressure difference and high air supply temperature in the prior art.

[0009] To solve the above-mentioned technical problems, embodiments of the present invention provide a bearing air supply system for an air-suspension compressor, comprising:

[0010] The compressor supply circuit is connected between the evaporator and the air suspension compressor. The air supply compressor supplies air to the bearing of the air suspension compressor, and the gas flowing out of the bearing returns to the evaporator.

[0011] A condenser gas supply circuit is connected to the condenser, the air-suspended compressor, and the evaporator. Gas is supplied to the bearing through the condenser, and gas flowing out of the bearing returns to the evaporator. The compressor gas supply circuit and the condenser gas supply circuit share a common part, which includes a gas supply tank.

[0012] A cooling circuit is used to exchange heat with the gas supplied to the bearing by the gas compressor or the condenser, so as to stabilize the gas supply temperature at the target gas supply temperature.

[0013] A gas supply pressure stabilizing pipeline is connected between the gas supply tank and the evaporator to regulate the pressure of the gas supply tank so that the gas supply pressure difference is stabilized at the target gas supply pressure difference.

[0014] Optionally, the common part further includes: a heat exchanger and a bearing gas supply and return pipeline;

[0015] The heat exchanger includes a first heat exchange pipeline and a second heat exchange pipeline. The first heat exchange pipeline is connected between the gas supply outlet of the gas supply tank and the bearing inlet of the air suspension compressor, and the second heat exchange pipeline belongs to the cooling circuit.

[0016] The bearing air supply and return pipeline is connected between the bearing outlet of the air suspension compressor and the return port of the evaporator.

[0017] Optionally, a first check valve is provided between the first heat exchange pipeline and the air suspension compressor, and the first check valve is unidirectionally open from the first heat exchange pipeline to the air suspension compressor.

[0018] Optionally, the non-common part of the compressor gas supply circuit includes: a gas supply compressor, the inlet of which is connected to the gas outlet of the evaporator, and the outlet of which is connected to the first gas supply inlet of the gas supply tank.

[0019] Optionally, a second one-way valve is provided between the gas supply compressor and the gas supply tank, and the second one-way valve is unidirectionally open from the gas supply compressor to the gas supply tank.

[0020] Optionally, the first end of the non-common pipeline of the condenser gas supply circuit is connected between the exhaust port of the air suspension compressor and the condenser, and the second end is connected to the second gas supply inlet of the gas supply tank.

[0021] A third check valve is installed on the non-common pipeline of the condenser gas supply circuit, and the third check valve is unidirectionally open from the condenser to the gas supply tank.

[0022] Optionally, the cooling circuit includes: a refrigerant pump, a first valve, and a heat exchanger connected in sequence;

[0023] The inlet of the refrigerant pump is connected between the throttling component and the evaporator, and the outlet of the refrigerant pump is connected to the first end of the first valve;

[0024] The second end of the first valve is connected to the inlet of the second heat exchange pipeline of the heat exchanger, and the outlet of the second heat exchange pipeline is connected to the return gas port of the evaporator.

[0025] Optionally, the first end of the gas supply pressure stabilizing pipeline is connected to the pressure stabilizing outlet of the gas supply tank, and the second end is connected to the return gas port of the evaporator;

[0026] The gas supply and pressure stabilizing pipeline is equipped with a valve with an adjustable opening.

[0027] Optionally, the bearing air supply system further includes: an emergency refrigerant pump supply line, the inlet of which is connected to the outlet of the refrigerant pump, and the outlet of which is connected to the bearing inlet of the air suspension compressor.

[0028] The refrigerant pump emergency supply line is equipped with a second valve and a fourth check valve.

[0029] Optionally, the bearing air supply system further includes:

[0030] A first pressure sensor, located at the gas supply tank, is used to detect the pressure of the gas supply tank;

[0031] The second pressure sensor, located at the air-suspension compressor, is used to detect the motor cavity pressure of the air-suspension compressor;

[0032] A temperature sensor, located at the bearing inlet of the air-suspension compressor, is used to detect the supply air temperature.

[0033] Optionally, the bearing air supply system further includes:

[0034] The third pressure sensor, located at the bearing inlet of the air-suspension compressor, is used to detect the liquid supply pressure.

[0035] This invention also provides a bearing air supply control method for an air-suspension compressor, applied to the bearing air supply system of the air-suspension compressor described in this invention. The method includes:

[0036] Calculate the difference between the condensing pressure and the motor cavity pressure of the air-suspended compressor, and compare the difference with the target supply pressure difference;

[0037] The circuit for supplying air to the bearings of the air-suspension compressor is determined based on the comparison results;

[0038] The pressure of the gas supply tank is adjusted using the gas supply pressure stabilization pipeline to keep the gas supply pressure difference stable at the target gas supply pressure difference.

[0039] The supply air temperature is adjusted using a cooling circuit to stabilize it at the target supply air temperature.

[0040] Optionally, the circuit for supplying air to the bearings of the air-suspension compressor is determined based on the comparison results, including:

[0041] If the difference is less than the target gas supply pressure difference, the gas supply compressor, refrigerant pump and first valve are turned on and the second valve is turned off to supply gas to the bearing through the compressor gas supply circuit;

[0042] If the difference is greater than or equal to the target gas supply pressure difference, then the gas supply compressor is turned off, the refrigerant pump and the first valve are turned on, and the second valve is turned off, so as to supply gas to the bearing through the condenser gas supply circuit.

[0043] Optionally, the pressure of the gas supply tank can be adjusted using a gas supply pressure stabilizing pipeline to keep the gas supply pressure difference stable at the target gas supply pressure difference, including:

[0044] Calculate the difference between the pressure in the air supply tank and the pressure in the motor cavity to obtain the air supply pressure difference;

[0045] If the gas supply pressure difference is less than the difference between the target gas supply pressure difference and the first preset value, then reduce the opening of the valve in the gas supply pressure stabilizing pipeline;

[0046] If the gas supply pressure difference is greater than the sum of the target gas supply pressure difference and the first preset value, then the opening degree of the valve in the gas supply pressure stabilizing pipeline is increased.

[0047] Optionally, the supply air temperature can be adjusted using a cooling circuit to stabilize it at the target supply air temperature, including:

[0048] Monitor the gas supply temperature;

[0049] If the gas supply temperature is less than the difference between the target gas supply temperature and the second preset value, then reduce the speed of the refrigerant pump.

[0050] If the gas supply temperature is greater than the sum of the target gas supply temperature and the second preset value, then the speed of the refrigerant pump is increased.

[0051] Optionally, the method further includes:

[0052] If the compressor fails and stops during unit operation and the bearing is supplied with air through the compressor air supply circuit, the refrigerant pump and the second valve are opened and the first valve is closed to switch to the refrigerant pump emergency liquid supply line to supply liquid to the bearing.

[0053] The speed of the refrigerant pump is controlled according to the supply pressure differential to stabilize the supply pressure differential at the target supply pressure differential until the air suspension compressor stops operating.

[0054] Optionally, controlling the speed of the refrigerant pump based on the supply pressure differential includes:

[0055] The difference between the supply pressure and the motor cavity pressure is calculated to obtain the supply pressure difference;

[0056] If the pressure difference of the supply pressure is less than the difference between the target supply pressure difference and the first preset value, then the speed of the refrigerant pump is increased;

[0057] If the pressure difference of the supply pressure is greater than the sum of the target air supply pressure difference and the first preset value, then the speed of the refrigerant pump is reduced.

[0058] This invention also provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method described in this invention.

[0059] This invention also provides a non-volatile computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method described in this invention.

[0060] By applying the technical solution of this invention, and by setting up a compressor air supply circuit and a condenser air supply circuit, the air supply compressor or condenser can supply air to the bearings of the air-suspended compressor according to different operating states of the unit. This ensures the normal suspension operation of the air-suspended bearings. By setting up an air supply pressure stabilizing pipeline, a stable air supply pressure difference is ensured. By setting up a cooling circuit, a suitable air supply temperature is ensured. This solves the problems of unstable air supply pressure difference and high air supply temperature in the bearings of the air-suspended compressor. Through the coordination of the air supply, pressure stabilization, and cooling circuits, the stable operation of the air-suspended bearings is ensured, thereby ensuring the efficient, stable, and safe operation of the unit and effectively improving the reliability of the unit. Attached Figure Description

[0061] Figure 1 This is a schematic diagram of the bearing air supply system of the air suspension compressor provided in Embodiment 1 of the present invention;

[0062] Figure 2This is another schematic diagram of the bearing air supply system of the air suspension compressor provided in Embodiment 1 of the present invention;

[0063] Figure 3 This is a flowchart of the bearing air supply control method for an air-suspended compressor provided in Embodiment 2 of the present invention;

[0064] Explanation of reference numerals in the attached figures:

[0065] 1. Air-suspension compressor; 2. Condenser; 3. Throttling component; 4. Evaporator;

[0066] A. Gas supply and pressure stabilizing pipeline; B. Bearing gas supply and return pipeline; C. Cooling plate return pipeline; D. Refrigerant pump emergency liquid supply pipeline.

[0067] 5. Gas compressor, 6. Gas tank, 7. Heat exchanger (i.e., cooling plate heat exchanger), 8. Refrigerant pump, 81. First valve, 82. Second valve, 61. Adjustable valve opening.

[0068] First check valve 71, first filter 72, second check valve 51, second filter 52, third check valve 21, third filter 41, fourth check valve 83;

[0069] First pressure sensor 91, second pressure sensor 92, temperature sensor 93, third pressure sensor 94, condensation pressure sensor 95, evaporation pressure sensor 96, check valve 10. Detailed Implementation

[0070] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0071] It should be noted that the terms "first," "second," etc., used in the specification, claims, and drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0072] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0073] The optional embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0074] Example 1

[0075] This embodiment provides a bearing air supply system for an air-suspension compressor, which can provide a stable air supply to the bearing of the air-suspension compressor, and the air supply temperature is within an appropriate range, ensuring stable bearing suspension and effectively improving the reliability of the unit.

[0076] Figure 1 and Figure 2 This is a schematic diagram of the bearing air supply system of the air-suspension compressor provided in Embodiment 1 of the present invention, as shown below. Figure 1 and Figure 2 As shown, the unit containing the air-suspension compressor includes: air-suspension compressor 1, condenser 2, throttling component 3 and evaporator 4, which form a refrigerant circulation loop for refrigeration or heating.

[0077] The bearing air supply system of the air-suspension compressor includes: compressor air supply circuit, condenser air supply circuit, cooling circuit and air supply pressure stabilizing pipeline A.

[0078] The compressor gas supply circuit connects the evaporator 4 and the air-suspension compressor 1, supplying gas to the bearings of the air-suspension compressor 1 via the gas supply compressor 5. The gas flowing out of the bearings returns to the evaporator 4. The compressor gas supply circuit draws gas from the low-pressure side and supplies it via the gas supply compressor 5. This circuit is typically activated to supply gas to the bearings during unit startup, shutdown, or when the condenser pressure is low during operation.

[0079] The condenser gas supply circuit connects to condenser 2, air-suspended compressor 1, and evaporator 4. Gas is supplied to the bearings through condenser 2, and the gas flowing out of the bearings returns to evaporator 4. The condenser gas supply circuit draws gas from the high-pressure side. Generally, this circuit is opened to supply gas to the bearings after the unit has completed startup and is operating normally, and when the condenser pressure is high.

[0080] The compressor gas supply circuit and the condenser gas supply circuit share a common part, which includes a gas supply tank 6. Gas from the gas supply compressor 5 or gas from the condenser 2 first goes to the gas supply tank 6 and then to the bearing of the air suspension compressor 1.

[0081] The cooling circuit is used to exchange heat with the gas supplied to the bearing by the gas compressor 5 or condenser 2, so as to stabilize the gas supply temperature at the target gas supply temperature. The target gas supply temperature T0 can be set according to the actual situation. Stabilizing the gas supply temperature at the target gas supply temperature means that the actual gas supply temperature is within the range of [T0-x, T0+x], and as close to T0 as possible. x can be set according to the actual situation, generally taking a small value, and x can also be 0.

[0082] Gas supply pressure stabilization line A connects to gas supply tank 6 and evaporator 4 to regulate the pressure in the gas supply tank, stabilizing the gas supply pressure difference at the target gas supply pressure difference. The target gas supply pressure difference P0 can be set according to actual conditions. Stabilizing the gas supply pressure difference at the target gas supply pressure difference means that the actual gas supply pressure difference is within the range [P0-y, P0+y], and should approach P0 as much as possible. y can be set according to actual conditions, generally taking a small value, and y can also be 0.

[0083] This embodiment, by setting up a compressor air supply circuit and a condenser air supply circuit, uses the air supply compressor or condenser to supply air to the bearings of the air-suspended compressor according to different operating states of the unit. This ensures the normal suspension operation of the air-suspended bearings. By setting up an air supply pressure stabilizing pipeline, a stable air supply pressure difference is ensured. By setting up a cooling circuit, a suitable air supply temperature is ensured. This solves the problems of unstable air supply pressure difference and high air supply temperature of the bearings in the air-suspended compressor. Through the coordination of the air supply, pressure stabilization and cooling circuits, the stable operation of the air-suspended bearings is ensured, thereby ensuring the efficient, stable and safe operation of the unit and effectively improving the reliability of the unit.

[0084] The common portion of the compressor gas supply circuit and the condenser gas supply circuit also includes: a heat exchanger 7 (i.e., a cooling plate heat exchanger) and a bearing gas supply and return line B. The heat exchanger 7 includes a first heat exchange line and a second heat exchange line. The first heat exchange line connects the gas supply outlet of the gas supply tank 6 to the bearing inlet of the air-suspended compressor 1, and the second heat exchange line belongs to the cooling circuit. The bearing gas supply and return line B connects the bearing outlet of the air-suspended compressor 1 to the return port of the evaporator 4. In this embodiment, the heat exchanger 7 enables heat exchange of the gas supplied to the bearing by the gas supply compressor 5 or the condenser 2, thereby helping to ensure a suitable gas supply temperature.

[0085] Furthermore, such as Figure 2 As shown, a first one-way valve 71 is provided between the first heat exchange pipeline and the air suspension compressor 1. The first one-way valve 71 is unidirectionally open from the first heat exchange pipeline to the air suspension compressor 1. In this embodiment, the first one-way valve 71 can prevent the backflow of gas supplied to the bearing.

[0086] Preferably, a first filter 72 may be provided between the first one-way valve 71 and the air suspension compressor 1 to filter out impurities.

[0087] The non-common part of the compressor supply circuit includes: a supply compressor 5, the inlet of which is connected to the gas outlet of the evaporator 4, and the outlet of the supply compressor 5 connected to the first supply inlet of the supply tank 6. In this embodiment, the supply compressor 5 can process and pressurize the gas taken from the low-pressure side and supply it to the supply tank 6.

[0088] Furthermore, such as Figure 2 As shown, a second check valve 51 is provided between the gas compressor 5 and the gas tank 6. The second check valve 51 is unidirectionally open from the gas compressor 5 to the gas tank 6. In this embodiment, the second check valve 51 can prevent the backflow of gas output from the gas compressor.

[0089] Preferably, a second filter 52 can be provided between the evaporator 4 and the gas supply compressor 5 to filter out impurities.

[0090] The first end of the non-common pipeline of the condenser gas supply circuit is connected between the exhaust port of the air-suspended compressor 1 and the condenser 2, and the second end is connected to the second gas supply inlet of the gas supply tank 6. A third check valve 21 is installed in the non-common pipeline of the condenser gas supply circuit, which is unidirectionally open from the condenser 2 to the gas supply tank 6. In this embodiment, the third check valve 21 prevents gas backflow.

[0091] The cooling circuit includes a refrigerant pump 8, a first valve 81, and a heat exchanger 7 connected in sequence. The inlet of the refrigerant pump 8 is connected between the throttling device 3 and the evaporator 4, and the outlet of the refrigerant pump 8 is connected to the first end of the first valve 81. The second end of the first valve 81 is connected to the inlet of the second heat exchange pipe of the heat exchanger 7, and the outlet of the second heat exchange pipe is connected to the return gas port of the evaporator 4 (this section is the cooling plate return gas pipe C). In this embodiment, the cooling circuit uses the refrigerant pump 8 to draw liquid from between the throttling device 3 and the evaporator 4 to achieve heat exchange and cooling of the supplied gas. By controlling the speed of the refrigerant pump 8, the temperature of the supplied gas can be adjusted.

[0092] Preferred, Reference Figure 2 A third filter 41 can also be installed between the evaporator 4 and the refrigerant pump 8 to filter out impurities.

[0093] The first end of the gas supply pressure stabilizing line A is connected to the pressure stabilizing outlet of the gas supply tank 6, and the second end is connected to the return gas port of the evaporator 4. An adjustable valve 61, specifically an electronic expansion valve, is installed on the gas supply pressure stabilizing line A. By controlling the opening of valve 61, the pressure in the gas supply tank can be adjusted to ensure a stable gas supply pressure differential.

[0094] Considering that when using gas compressor 5 for gas supply, there is a possibility of abnormal shutdown of gas compressor 5, resulting in a sudden drop in gas supply pressure. This could cause the bearing to fall due to high-speed rotation, leading to bearing damage. To solve this problem, refer to... Figure 2 The bearing air supply system in this embodiment also includes: an emergency liquid supply line D for the refrigerant pump, the inlet of which is connected to the outlet of the refrigerant pump 8, and the outlet of which is connected to the bearing inlet of the air suspension compressor 1; a second valve 82 and a fourth check valve 83 are provided on the emergency liquid supply line D along the liquid supply direction.

[0095] Turning on the refrigerant pump 8 and the first valve 81 activates the cooling circuit, enabling cooling of the supplied gas. Turning on the refrigerant pump 8 and the second valve 82 allows for emergency liquid supply using the backup liquid supply system in case of an anomaly in the main gas supply system (i.e., a failure or shutdown of the gas compressor 5).

[0096] In this embodiment, when the conditions for supplying gas to the condenser 2 are not met and gas is supplied through the gas supply compressor 5, the refrigerant pump is used as an emergency backup liquid supply system. When the gas supply compressor 5 malfunctions, the system is switched to continue supplying liquid to the bearing, allowing the bearing to remain suspended for a period of time until the motor of the air suspension compressor 1 stops running. This avoids the situation where the bearing suddenly falls and wears down due to the lack of gas supply during the motor coasting phase, which would otherwise cause the bearing to be damaged.

[0097] The first valve 81 and the second valve 82 can be valves with on / off control functions, such as solenoid valves.

[0098] To monitor whether the supply pressure difference and supply temperature have reached the target, the above-mentioned bearing air supply system may also include:

[0099] The first pressure sensor 91 is located at the gas supply tank 6 and is used to detect the pressure of the gas supply tank.

[0100] The second pressure sensor 92 is located at the air suspension compressor 1 and is used to detect the pressure in the motor cavity of the air suspension compressor 1.

[0101] Temperature sensor 93 is located at the bearing inlet of air suspension compressor 1 and is used to detect the supply air temperature.

[0102] The air supply pressure difference equals the bearing inlet pressure minus the bearing outlet pressure. The air supply tank pressure can be understood as the inlet pressure of the air bearing, and the motor cavity pressure can be understood as the bearing outlet pressure. Therefore, the actual air supply pressure difference can be obtained by calculating the difference between the air supply tank pressure and the motor cavity pressure.

[0103] The aforementioned bearing air supply system may further include a third pressure sensor 94, located at the bearing inlet of the air-suspension compressor 1, used to detect the liquid supply pressure. The difference between the liquid supply pressure and the motor cavity pressure is the actual liquid supply differential. In case of emergency liquid supply, the liquid supply differential can be stabilized at the target air supply differential by controlling the speed of the refrigerant pump 8.

[0104] refer to Figure 2The bearing air supply system of the air-suspension compressor includes the following paths:

[0105] (1) Compressor air supply circuit, circuit composition: evaporator 4 → second filter 52 → air supply compressor 5 → second check valve 51 → air supply tank 6 → cooling plate heat exchanger 7 → first check valve 71 → first filter 72 → temperature sensor 93 → third pressure sensor 94 → air suspension compressor 1 (air bearing) → bearing air supply and return pipeline B → evaporator 4.

[0106] The function of this circuit is to provide a stable air supply to the air bearing. This circuit is generally activated when the condenser pressure is low during unit startup, shutdown, or operation and cannot serve as an air source for the bearing.

[0107] (2) Condenser gas supply circuit, circuit composition: condenser 2 → third check valve 21 → gas supply tank 6 → cooling plate heat exchanger 7 → first check valve 71 → first filter 72 → temperature sensor 93 → third pressure sensor 94 → air suspension compressor 1 (air bearing) → bearing gas supply and return pipeline B → evaporator 4.

[0108] The function of this circuit is to provide a stable air supply to the air bearing. Generally, this circuit is turned on after the unit has completed startup and normal operation, and when the condenser pressure is high enough to serve as the air source for the bearing.

[0109] (3) Cooling circuit, circuit composition: evaporator 4 → third filter 41 → refrigerant pump 8 → first valve 81 → cooling plate heat exchanger 7 → cooling plate heat exchanger return gas pipeline C → evaporator 4.

[0110] The function of this circuit is to provide a stable supply of air to the air bearing for cooling. Through heat exchange between the cooling plate and the supply air refrigerant, the supply air temperature is reduced, ensuring the safety of the bearing. Generally, when the above-mentioned air supply circuits (1) and (2) are opened, the cooling circuit is also opened.

[0111] (4) Emergency liquid supply circuit for refrigerant pump, circuit composition: evaporator 4 → third filter 41 → refrigerant pump 8 → second valve 82 → fourth check valve 83 → first filter 72 → temperature sensor 93 → third pressure sensor 94 → air suspension compressor 1 (air bearing) → bearing air supply and return pipeline B → evaporator 4.

[0112] The function of this circuit is to provide emergency liquid supply to the air bearing. The refrigerant pump 8 draws liquid refrigerant from the bottom of the evaporator 4 and supplies it directly to the air bearing of the compressor. This circuit is activated when the air compressor 5 stops abnormally during unit operation to ensure that the bearing is suspended by liquid supply during coasting and to avoid damage to the bearing.

[0113] (5) Gas supply and pressure stabilization circuit, circuit composition: gas supply tank 6 → adjustable valve 61 → evaporator 4.

[0114] The function of this circuit is to adjust the opening of valve 61 to bypass the pressure of the air supply tank, so that the air supply pressure difference is within an appropriate range, thereby ensuring stable operation of the bearing.

[0115] Figure 2 The various ports of the evaporator 4 shown can be combined according to the actual situation. For example, the bearing gas supply and return line B, the cooling plate gas exchange line C, and the gas supply and pressure stabilizing line A all return to the same port of the evaporator 4.

[0116] Example 2

[0117] This embodiment provides a bearing air supply control method for an air-suspension compressor, which is applied to the bearing air supply system of the air-suspension compressor described in the above embodiment.

[0118] Figure 3 This is a flowchart of the bearing air supply control method for the air suspension compressor provided in Embodiment 2 of the present invention, as shown below. Figure 3 As shown, the method includes the following steps:

[0119] S301, calculate the difference between the condensing pressure and the motor cavity pressure of the air suspension compressor, and compare the difference with the target supply pressure difference.

[0120] S302, Determine the circuit for supplying air to the bearings of the air suspension compressor based on the comparison results.

[0121] S303 uses the gas supply pressure stabilization pipeline to adjust the pressure of the gas supply tank so that the gas supply pressure difference is stabilized at the target gas supply pressure difference.

[0122] S304 uses a cooling circuit to adjust the gas supply temperature so that the gas supply temperature is stabilized at the target gas supply temperature.

[0123] By comparing the above difference with the target supply pressure difference, the level of the condensing pressure can be determined. If the condensing pressure is high enough to meet the supply pressure difference requirement, the condenser supply circuit can be used to supply gas to the bearing. If the condensing pressure is too low, the compressor supply circuit should be used. Regardless of whether the condenser or compressor supply circuit is used to supply gas to the bearing, real-time adjustment of the supply pressure difference and supply temperature is necessary during the supply process to ensure a stable supply pressure difference and suitable supply temperature. The execution order of steps S303 and S304 is not important.

[0124] This embodiment switches different air supply circuits to supply air to the bearings of the air-suspended compressor according to the actual operating conditions of the unit. This ensures that the air-suspended bearings can operate normally. The air supply pressure stabilization pipeline ensures a stable air supply pressure difference, and the cooling circuit ensures a suitable air supply temperature. This solves the problems of unstable air supply pressure difference and high air supply temperature in the bearings of the air-suspended compressor. Through the coordinated control of the air supply, pressure stabilization, and cooling circuits, the stable operation of the air-suspended bearings is ensured, thereby ensuring the efficient, stable, and safe operation of the unit and effectively improving the reliability of the unit.

[0125] In one embodiment, determining the circuit for supplying air to the bearings of the air-suspended compressor based on the comparison results includes:

[0126] If the difference is less than the target gas supply pressure difference, the gas supply compressor 5, refrigerant pump 8 and first valve 81 are turned on, and the second valve 82 is turned off, so as to supply gas to the bearing through the compressor gas supply circuit.

[0127] If the difference is greater than or equal to the target gas supply pressure difference, then shut down the gas supply compressor 5, turn on the refrigerant pump 8 and the first valve 81, and close the second valve 82 to supply gas to the bearing through the condenser gas supply circuit.

[0128] This implementation method, based on the difference between the condensing pressure and the motor cavity pressure of the air-suspended compressor, as well as the target air supply pressure difference, can switch the bearing air supply circuit, thereby ensuring the normal suspension operation of the air-suspended bearing during the unit start-up, shutdown, and operation phases.

[0129] In one embodiment, the pressure of the gas supply tank is adjusted using a gas supply pressure stabilization pipeline to stabilize the gas supply pressure difference at a target gas supply pressure difference. This includes: calculating the difference between the gas supply tank pressure and the motor cavity pressure to obtain the gas supply pressure difference; if the gas supply pressure difference is less than the difference between the target gas supply pressure difference and a first preset value, then reducing the opening of valve 61 in the gas supply pressure stabilization pipeline; if the gas supply pressure difference is greater than the sum of the target gas supply pressure difference and the first preset value, then increasing the opening of valve 61 in the gas supply pressure stabilization pipeline.

[0130] The first preset value y is the allowable deviation of the target gas supply pressure difference P0. The first preset value can be set according to the actual situation. The value of the first preset value is generally small, or it can be 0.

[0131] This embodiment adjusts the opening of valve 61 on the gas supply pressure stabilizing pipeline according to the actual gas supply pressure difference, so that the actual gas supply pressure difference tends to the target gas supply pressure difference P0, thus ensuring the stability of the gas supply pressure difference.

[0132] In one embodiment, adjusting the supply gas temperature using a cooling circuit to stabilize the supply gas temperature at a target supply gas temperature includes: monitoring the supply gas temperature; if the supply gas temperature is less than the difference between the target supply gas temperature and a second preset value, reducing the speed of the refrigerant pump 8 to reduce the cooling capacity; if the supply gas temperature is greater than the sum of the target supply gas temperature and the second preset value, increasing the speed of the refrigerant pump 8 to increase the cooling capacity.

[0133] The second preset value x is the allowable deviation of the target gas supply temperature T0. The second preset value can be set according to the actual situation. The value of the second preset value is generally small, or it can be 0.

[0134] This embodiment adjusts the speed of the refrigerant pump 8 according to the actual gas supply temperature so that the actual gas supply temperature is within the range of T0±x, ensuring a suitable gas supply temperature.

[0135] Considering that when using the gas supply compressor 5 for gas supply, the gas supply compressor 5 may stop abnormally, the gas supply pressure may drop suddenly, and the bearing may fall due to high-speed rotation, which will lead to bearing damage.

[0136] To address this issue, the above method may further include: during unit operation and while the bearing is being supplied with air through the compressor air supply circuit, if a fault shutdown of the air supply compressor 5 is detected, the refrigerant pump 8 and the second valve 82 are opened, and the first valve 81 is closed to switch to the refrigerant pump emergency liquid supply line to supply liquid to the bearing; the speed of the refrigerant pump 8 is controlled according to the supply pressure differential to stabilize the supply pressure differential at the target supply pressure differential until the air suspension compressor 1 stops operating.

[0137] This embodiment utilizes a refrigerant pump as an emergency backup refrigerant supply system. In the event of an malfunction in the gas compressor 5, the system immediately switches to supplying refrigerant to the bearing, allowing it to remain suspended for a period until the motor of the air-suspended compressor 1 stops operating. This prevents the bearing from suddenly falling and damaging itself due to a lack of air supply during the motor's coasting phase, which could lead to bearing wear. Furthermore, controlling the speed of the refrigerant pump 8 based on the pressure difference ensures a stable pressure difference.

[0138] Furthermore, the speed of the refrigerant pump 8 is controlled based on the supply pressure difference, including: calculating the difference between the supply liquid pressure and the motor cavity pressure to obtain the supply pressure difference; if the supply pressure difference is less than the difference between the target supply air pressure difference and the first preset value, the speed of the refrigerant pump 8 is increased; if the supply pressure difference is greater than the sum of the target supply air pressure difference and the first preset value, the speed of the refrigerant pump 8 is decreased.

[0139] This embodiment adjusts the speed of the refrigerant pump 8 according to the actual supply pressure difference, so that the actual supply pressure difference tends to the target supply pressure difference P0, thus ensuring the stability of the supply pressure difference.

[0140] Example 3

[0141] This embodiment combines Figure 2 The air supply system for the bearing of the air-suspended compressor shown illustrates the above-mentioned bearing air supply control method. However, it is worth noting that this specific embodiment is only for better illustration of this application and does not constitute an improper limitation of this application.

[0142] based on Figure 2 The bearing air supply system of the air suspension compressor shown requires that the bearing air supply pressure difference (bearing inlet pressure - bearing outlet pressure) be within a certain range in order to ensure the normal suspension operation of the air suspension bearing. The air supply pressure difference and the air supply pressure difference are used as the basis for judging whether the bearing air supply is stable.

[0143] The air supply pressure difference = air supply tank pressure - motor cavity pressure. The air supply tank pressure is measured by the first pressure sensor 91, and the motor cavity pressure is measured by the second pressure sensor 92.

[0144] Hydraulic pressure difference = hydraulic supply pressure - motor cavity pressure. The hydraulic supply pressure is measured by the third pressure sensor 94.

[0145] The condensing pressure is measured using a condensing pressure sensor 95, and the gas supply temperature is measured using a temperature sensor 93.

[0146] Let the target gas supply pressure difference be P0, the liquid supply pressure be P1, the motor cavity pressure be P2, the gas supply tank pressure be P3, the condensation pressure be P4, the target gas supply temperature be T0, the gas supply pressure difference be P3-P2, and the liquid supply pressure difference be P1-P2.

[0147] Different gas supply circuits are switched according to different stages and states of unit operation. The specific operation control of each circuit is as follows:

[0148] (1) When the unit is in the start-up phase, P4-P2 < P0. The running compressor supply circuit supplies air to the bearings. The air supply compressor 5 is turned on. The opening of valve 61 on the air supply pressure stabilizing pipeline A is adjusted according to the air supply pressure difference (P3-P2) to make the air supply pressure difference approach the target air supply pressure difference P0. Specifically, when the air supply pressure difference is too high, valve 61 is opened wider, and when the air supply pressure difference is too low, valve 61 is closed smaller. The refrigerant pump 8 is turned on, the first valve 81 is opened, and the second valve 82 is closed. The operating speed of the refrigerant pump 8 is controlled according to the air supply temperature to make the air supply temperature within the range of the target air supply temperature T0 ± 5℃. Specifically, when the air supply temperature is too high, the operating speed of the refrigerant pump 8 is increased to increase the cooling capacity, and when the air supply temperature is too low, the operating speed of the refrigerant pump 8 is decreased to reduce the cooling capacity.

[0149] (2) When the unit completes the startup and enters the operation phase, when P4-P2<P0, the control operation of the above situation (1) is maintained.

[0150] (3) After the unit completes startup and enters the operation phase, when P4-P2≥P0, the condenser gas supply circuit is switched to supply gas to the bearing, and the gas supply compressor 5 is shut down. The opening of valve 61 on the gas supply pressure stabilizing pipeline A is adjusted according to the gas supply pressure difference (P3-P2) to make the gas supply pressure difference approach the target gas supply pressure difference P0. Specifically, when the gas supply pressure difference is too high, valve 61 is opened wider, and when the gas supply pressure difference is too low, valve 61 is closed smaller. The refrigerant pump 8 is turned on, the first valve 81 is opened, and the second valve 82 is closed. The operating speed of the refrigerant pump 8 is controlled according to the gas supply temperature to make the gas supply temperature within the range of the target gas supply temperature T0±5℃. Specifically, when the gas supply temperature is too high, the operating speed of the refrigerant pump 8 is increased to increase the cooling capacity, and when the gas supply temperature is too low, the operating speed of the refrigerant pump 8 is decreased to reduce the cooling capacity.

[0151] (4) When the unit is in operation and the bearing is supplied with air through the compressor air supply circuit, if the air supply compressor 5 fails and stops, at the moment of shutdown, the emergency liquid supply circuit of the refrigerant pump is switched to supply liquid to the bearing. The refrigerant pump 8 is turned on, the first valve 81 is closed, and the second valve 82 is opened. The operating speed of the refrigerant pump 8 is controlled according to the supply pressure difference to make the supply pressure difference (P1-P2) approach the target supply pressure difference P0. Specifically, when the supply pressure difference is too high, the operating speed of the refrigerant pump 8 is reduced; when the supply pressure difference is too low, the operating speed of the refrigerant pump 8 is increased. The refrigerant pump liquid supply is used as an emergency backup system. When the air supply is abnormal, the system is switched to continue supplying liquid to the bearing until the motor of the air suspension compressor stops running. This avoids the situation where the bearing cannot work properly due to the lack of air supply during the motor's coasting operation, which could lead to shaft wear and bearing damage.

[0152] Through the above controls, the gas supply, liquid supply, pressure stabilization, and cooling circuits are adjusted and coordinated according to different operating states of the unit to ensure efficient, stable, and safe operation of the unit.

[0153] This embodiment provides a stable air supply to the air-bearing compressor by coordinating the air supply, pressure stabilization, and cooling circuits, and controls the air supply temperature within an appropriate range to ensure stable operation of the air-bearing bearing. This, in turn, ensures efficient, stable, and safe operation of the unit, effectively improving its reliability. By combining the air supply system and the liquid supply system, as well as the air supply cooling and emergency liquid supply systems, the structure is simplified, resulting in more stable and safer bearing suspension.

[0154] Example 4

[0155] This embodiment provides a computer device, including: a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the method described in this embodiment of the invention.

[0156] Example 5

[0157] This embodiment provides a non-volatile computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method described in this embodiment of the invention.

[0158] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0159] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0160] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bearing air supply system for an air-suspension compressor, characterized in that, include: The compressor supply circuit is connected between the evaporator and the air suspension compressor. The air supply compressor supplies air to the bearing of the air suspension compressor, and the gas flowing out of the bearing returns to the evaporator. A condenser gas supply circuit is connected to the condenser, the air-suspended compressor, and the evaporator. Gas is supplied to the bearing through the condenser, and gas flowing out of the bearing returns to the evaporator. The compressor gas supply circuit and the condenser gas supply circuit share a common part, which includes a gas supply tank. A cooling circuit is used to exchange heat with the gas supplied to the bearing by the gas compressor or the condenser, so as to stabilize the gas supply temperature at the target gas supply temperature. A gas supply pressure stabilizing pipeline is connected between the gas supply tank and the evaporator to regulate the pressure of the gas supply tank so that the gas supply pressure difference is stabilized at the target gas supply pressure difference; The common part also includes: heat exchanger and bearing gas supply and return pipeline; The heat exchanger includes a first heat exchange pipeline and a second heat exchange pipeline. The first heat exchange pipeline is connected between the gas supply outlet of the gas supply tank and the bearing inlet of the air suspension compressor, and the second heat exchange pipeline belongs to the cooling circuit. The bearing air supply and return pipeline is connected between the bearing outlet of the air suspension compressor and the return port of the evaporator.

2. The bearing air supply system of the air-suspension compressor according to claim 1, characterized in that, A first check valve is provided between the first heat exchange pipeline and the air suspension compressor, and the first check valve is unidirectionally open from the first heat exchange pipeline to the air suspension compressor.

3. The bearing air supply system of the air-suspension compressor according to claim 1, characterized in that, The non-common part of the compressor gas supply circuit includes: a gas supply compressor, the inlet of which is connected to the gas outlet of the evaporator, and the outlet of which is connected to the first gas supply inlet of the gas supply tank.

4. The bearing air supply system of the air-suspension compressor according to claim 3, characterized in that, A second one-way valve is provided between the gas supply compressor and the gas supply tank, and the second one-way valve is open in one direction from the gas supply compressor to the gas supply tank.

5. The bearing air supply system of the air-suspension compressor according to claim 1, characterized in that, The first end of the non-common pipeline of the condenser air supply circuit is connected between the exhaust port of the air suspension compressor and the condenser, and the second end is connected to the second air supply inlet of the air supply tank. A third check valve is installed on the non-common pipeline of the condenser gas supply circuit, and the third check valve is unidirectionally open from the condenser to the gas supply tank.

6. The bearing air supply system of the air-suspension compressor according to claim 1, characterized in that, The cooling circuit includes: a refrigerant pump, a first valve, and a heat exchanger connected in sequence; The inlet of the refrigerant pump is connected between the throttling component and the evaporator, and the outlet of the refrigerant pump is connected to the first end of the first valve; The second end of the first valve is connected to the inlet of the second heat exchange pipeline of the heat exchanger, and the outlet of the second heat exchange pipeline is connected to the return gas port of the evaporator.

7. The bearing air supply system of the air-suspension compressor according to claim 1, characterized in that, The first end of the gas supply and pressure stabilizing pipeline is connected to the pressure stabilizing outlet of the gas supply tank, and the second end is connected to the return gas port of the evaporator. The gas supply and pressure stabilizing pipeline is equipped with a valve with an adjustable opening.

8. The bearing air supply system of the air-suspension compressor according to any one of claims 1 to 7, characterized in that, Also includes: An emergency refrigerant pump supply line is provided, with its inlet connected to the outlet of the refrigerant pump and its outlet connected to the bearing inlet of the air-suspension compressor. The refrigerant pump emergency supply line is equipped with a second valve and a fourth check valve.

9. The bearing air supply system of the air-suspension compressor according to any one of claims 1 to 7, characterized in that, Also includes: A first pressure sensor, located at the gas supply tank, is used to detect the pressure of the gas supply tank; The second pressure sensor, located at the air-suspension compressor, is used to detect the motor cavity pressure of the air-suspension compressor; A temperature sensor, located at the bearing inlet of the air-suspension compressor, is used to detect the supply air temperature.

10. The bearing air supply system of the air-suspension compressor according to claim 8, characterized in that, Also includes: The third pressure sensor, located at the bearing inlet of the air-suspension compressor, is used to detect the liquid supply pressure.

11. A bearing air supply control method for an air-suspension compressor, characterized in that, The method, applied to the bearing air supply system of the air-suspended compressor according to any one of claims 1 to 10, comprises: Calculate the difference between the condensing pressure and the motor cavity pressure of the air-suspended compressor, and compare the difference with the target supply pressure difference; The circuit for supplying air to the bearings of the air-suspension compressor is determined based on the comparison results; The pressure of the gas supply tank is adjusted using the gas supply pressure stabilization pipeline to keep the gas supply pressure difference stable at the target gas supply pressure difference. The supply air temperature is adjusted using a cooling circuit to stabilize it at the target supply air temperature.

12. The method according to claim 11, characterized in that, The circuit for supplying air to the bearings of the air-suspension compressor is determined based on the comparison results, including: If the difference is less than the target gas supply pressure difference, the gas supply compressor, refrigerant pump and first valve are turned on and the second valve is turned off to supply gas to the bearing through the compressor gas supply circuit; If the difference is greater than or equal to the target gas supply pressure difference, then the gas supply compressor is turned off, the refrigerant pump and the first valve are turned on, and the second valve is turned off, so as to supply gas to the bearing through the condenser gas supply circuit.

13. The method according to claim 11, characterized in that, Regulating the pressure of the gas supply tank using a gas supply pressure stabilizing pipeline to keep the gas supply pressure differential stable at the target gas supply pressure differential includes: Calculate the difference between the pressure in the air supply tank and the pressure in the motor cavity to obtain the air supply pressure difference; If the gas supply pressure difference is less than the difference between the target gas supply pressure difference and the first preset value, then reduce the opening of the valve in the gas supply pressure stabilizing pipeline; If the gas supply pressure difference is greater than the sum of the target gas supply pressure difference and the first preset value, then the opening degree of the valve in the gas supply pressure stabilizing pipeline is increased.

14. The method according to claim 11, characterized in that, Adjusting the supply air temperature using a cooling circuit to stabilize it at the target supply air temperature includes: Monitor the gas supply temperature; If the gas supply temperature is less than the difference between the target gas supply temperature and the second preset value, then reduce the speed of the refrigerant pump. If the gas supply temperature is greater than the sum of the target gas supply temperature and the second preset value, then the speed of the refrigerant pump is increased.

15. The method according to any one of claims 11 to 14, characterized in that, Also includes: If the compressor fails and stops during unit operation and the bearing is supplied with air through the compressor air supply circuit, the refrigerant pump and the second valve are opened and the first valve is closed to switch to the refrigerant pump emergency liquid supply line to supply liquid to the bearing. The speed of the refrigerant pump is controlled according to the supply pressure differential to stabilize the supply pressure differential at the target supply pressure differential until the air suspension compressor stops operating.

16. The method according to claim 15, characterized in that, Controlling the speed of the refrigerant pump based on the supply pressure differential includes: The difference between the supply pressure and the motor cavity pressure is calculated to obtain the supply pressure difference; If the pressure difference of the supply pressure is less than the difference between the target supply pressure difference and the first preset value, then the speed of the refrigerant pump is increased; If the pressure difference of the supply pressure is greater than the sum of the target air supply pressure difference and the first preset value, then the speed of the refrigerant pump is reduced.

17. A computer device, comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that the processor, when executing the computer program, implements the steps of the method according to any one of claims 11 to 16.

18. A non-volatile computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 11 to 16.

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