Magnetic Levitation Centrifugal Compression System and its Control Method

Abstract

This invention belongs to the field of compressor technology and discloses a magnetic levitation centrifugal compression system and its control method. The system includes a centrifugal compressor, a magnetic levitation motor, a main regulating valve, a bypass regulating valve, a turbine, a generator, and an energy storage device. The magnetic levitation motor and the centrifugal compressor are driven together; the main regulating valve is connected to the centrifugal compressor and is used to output the working fluid; the bypass regulating valve is connected to the centrifugal compressor; the turbine is connected to the bypass regulating valve; the generator is driven together with the turbine; and the energy storage device is electrically connected to the generator and the magnetic levitation motor. By opening the bypass regulating valve to input the working fluid into the turbine, a sharp increase in pressure at the output of the centrifugal compressor can be avoided. Simultaneously, the turbine and generator can convert the energy of the working fluid into electrical energy, which can be stored in the energy storage device or supplied to the magnetic levitation motor, achieving energy recovery and utilization. This also prevents sudden power outages of the magnetic levitation motor, thereby improving economy and safety.

Description

Technical Field

[0001] This invention relates to the field of compressor technology, and in particular to a magnetic levitation centrifugal compression system and its control method. Background Technology

[0002] In compressor systems, using a magnetic levitation motor to drive the compressor reduces internal contact friction and mechanical losses, enabling high speeds of tens of thousands of revolutions per minute at a lower cost, thereby achieving a higher compression ratio and higher work efficiency. Simultaneously, eliminating the lubrication system results in a very clean working fluid, reducing maintenance costs.

[0003] However, due to the significant increase in rotational speed, the rotating and magnetically levitated components in the system are subjected to substantial impacts and concentrated local loads when sudden changes in operating conditions occur, leading to safety risks and hindering the widespread application of magnetically levitated centrifugal compression systems. Furthermore, centrifugal compressors also suffer from the problem of being unable to operate stably and economically at low loads for extended periods.

[0004] Therefore, there is an urgent need for a magnetic levitation centrifugal compression system and its control method to solve the above-mentioned technical problems. Summary of the Invention

[0005] One objective of this invention is to provide a magnetic levitation centrifugal compression system that can reduce safety risks during sudden changes in operating conditions and improve the economy and safety of the magnetic levitation centrifugal compression system during low-load operation.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A magnetic levitation centrifugal compression system includes:

[0008] A centrifugal compressor, which is capable of compressing a low-pressure working fluid into a high-pressure working fluid and outputting it;

[0009] A magnetic levitation motor, wherein the magnetic levitation motor is connected to the centrifugal compressor in a transmission connection;

[0010] A main regulating valve is provided, with its input end connected to the output end of the centrifugal compressor. The output end of the main regulating valve is used to output the high-pressure working fluid from the magnetic levitation centrifugal compression system.

[0011] A bypass regulating valve is provided, wherein the input end of the bypass regulating valve is connected to the output end of the centrifugal compressor;

[0012] The turbine, wherein the input end of the turbine is connected to the output end of the bypass regulating valve;

[0013] A generator, wherein the generator is connected to the turbine drive;

[0014] An energy storage device is electrically connected between the generator and the magnetic levitation motor. The high-voltage working fluid can drive the generator through the turbine to selectively supply power to at least one of the energy storage device and the magnetic levitation motor. The energy storage device can supply power to the magnetic levitation motor.

[0015] In some embodiments, the magnetic levitation centrifugal compression system further includes:

[0016] A hybrid buffer, the output of which is connected to the input of the centrifugal compressor, and the hybrid buffer having a first input and a second input, the first input being connected to the output of the turbine, and the second input being used to input the low-pressure working fluid into the magnetic levitation centrifugal compression system.

[0017] In some embodiments, the magnetic levitation centrifugal compression system further includes:

[0018] A check valve is connected between the turbine and the mixing buffer.

[0019] In some embodiments, the magnetic levitation centrifugal compression system further includes:

[0020] A temperature transmitter, wherein the temperature transmitter is connected between the main regulating valve and the centrifugal compressor; and / or,

[0021] A pressure transmitter, wherein the pressure transmitter is connected between the main control valve and the centrifugal compressor; and / or,

[0022] A flow transmitter, wherein the flow transmitter is connected between the main regulating valve and the centrifugal compressor; and / or,

[0023] A gearbox, which is drive-connected between the turbine and the generator.

[0024] In some embodiments, the rotor of the centrifugal compressor and the output end of the magnetic levitation motor are rigidly connected coaxially.

[0025] In some embodiments, the energy storage device includes a supercapacitor bank, a first current converter, and a second current converter. The first current converter, the supercapacitor bank, and the second current converter are sequentially connected between the generator and the magnetic levitation motor. A first circuit breaker is connected between the first current converter and the generator, and a second circuit breaker is connected between the second current converter and the magnetic levitation motor.

[0026] A third circuit breaker is connected between the generator and the magnetic levitation motor.

[0027] Another objective of this invention is to provide a control method for a magnetic levitation centrifugal compression system that can reduce safety risks during sudden changes in operating conditions.

[0028] To achieve this objective, the present invention adopts the following technical solution:

[0029] A control method for a magnetic levitation centrifugal compression system, implemented in the aforementioned magnetic levitation centrifugal compression system, the control method comprising:

[0030] Power generation steps: Open the bypass regulating valve to input the high-pressure working fluid into the turbine to drive the generator to generate electricity;

[0031] Energy storage step: Input the electrical energy generated by the generator into the energy storage device for storage;

[0032] Power supply step: The electrical energy generated by the generator and / or the electrical energy stored in the energy storage device is supplied to the magnetic levitation motor.

[0033] In some embodiments, when the magnetic levitation centrifugal compression system is started...

[0034] Close the main regulating valve, start the magnetic levitation motor, and implement the power generation step, the energy storage step, and the power supply step;

[0035] Once the high-pressure working fluid reaches the preset pressure and preset flow rate, the main regulating valve is gradually opened, and the bypass regulating valve is gradually closed.

[0036] In some embodiments, when the magnetic levitation centrifugal compression system is powered off and shut down...

[0037] The main regulating valve is gradually closed, and the bypass regulating valve is simultaneously gradually opened to implement the power generation step, followed by the energy storage step, the power supply step, or the energy storage step and the power supply step.

[0038] In some embodiments, when the real-time frequency of the magnetic levitation motor drops to a safe frequency, and it is necessary to further reduce the flow rate of the high-pressure working fluid output by the magnetic levitation centrifugal compression system,

[0039] Open the bypass regulating valve to input a portion of the high-pressure working fluid into the turbine to drive the generator to generate electricity and supply power to the magnetic levitation motor.

[0040] The above technical solution has the following advantages or beneficial effects:

[0041] In this system, when sudden changes occur in operating conditions, such as blockage at the output of the magnetic levitation centrifugal compressor or a sudden power outage, the bypass regulating valve is opened to input the high-pressure working fluid into the turbine, thus preventing a sharp increase in pressure at the output of the centrifugal compressor. Simultaneously, the turbine and generator can convert the energy of the high-pressure working fluid into electrical energy, which can be stored in an energy storage device or supplied to the magnetic levitation motor. This achieves energy recovery and utilization, and also prevents sudden power outages to the magnetic levitation motor, thereby improving the economy and safety of the magnetic levitation centrifugal compressor system.

[0042] Through the aforementioned power generation, energy storage, and power supply steps, the high-pressure working fluid can be input into the turbine, preventing a sharp increase in pressure at the centrifugal compressor's output. Furthermore, the combination of these steps converts the high-pressure working fluid's energy into electrical energy, which can be stored in an energy storage device or supplied to the magnetic levitation motor. This achieves energy recovery and utilization, improving the economy and safety during low-load operation. It also prevents sudden power outages to the magnetic levitation motor, thereby enhancing the economy and safety of the magnetic levitation centrifugal compression system. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the structure of the end-effector magnetic levitation centrifugal compression system in an embodiment of the present invention.

[0044] In the picture:

[0045] 1. Magnetic levitation motor; 2. Centrifugal compressor; 3. Main regulating valve; 4. Bypass regulating valve; 5. Turbine; 6. Gearbox; 7. Generator; 8. First circuit breaker; 9. First current converter; 10. Supercapacitor bank; 11. Second current converter; 12. Second circuit breaker; 13. Third circuit breaker; 14. Mixing buffer; 15. Check valve; 16. Temperature transmitter; 17. Pressure transmitter; 18. Flow transmitter. Detailed Implementation

[0046] The present invention 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 merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0047] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," "fixed," and "abutting" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0048] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0049] In the description of this embodiment, the terms "upper," "lower," "right," and "left," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0050] The following is based on Figure 1 This invention introduces the magnetic levitation centrifugal compression system and its control method.

[0051] Specifically, such as Figure 1As shown, the magnetic levitation centrifugal compression system mainly includes a centrifugal compressor 2, a magnetic levitation motor 1, a main regulating valve 3, a bypass regulating valve 4, a turbine 5, a generator 7, and an energy storage device. The centrifugal compressor 2 is a functional component that compresses a low-pressure working fluid into a high-pressure working fluid. The low-pressure working fluid enters the centrifugal compressor 2 from its input end and, under the compression work of the centrifugal compressor 2, is transformed into a high-pressure working fluid, which is then output from the output end of the centrifugal compressor 2. The magnetic levitation motor 1 is driven by the centrifugal compressor 2, enabling the rotor of the centrifugal compressor 2 to rotate at high speed, thereby compressing the low-pressure working fluid. The input end of the main regulating valve 3 and the output end of the centrifugal compressor 2 are connected by a pipeline. When the main regulating valve 3 is open, the high-pressure working fluid can be output to the magnetic levitation centrifugal compression system through the output end of the main regulating valve 3. The input end of the bypass regulating valve 4 and the output end of the centrifugal compressor 2 are also connected by a pipeline. When the bypass regulating valve 4 is open, the high-pressure working fluid can be input to the turbine 5 through the output end of the bypass regulating valve 4.

[0052] Turbine 5 and generator 7 are connected by a drive system. When high-pressure working fluid is input into turbine 5, the energy of the high-pressure working fluid can be converted into electrical energy and output through turbine 5 and generator 7. Generator 7 is electrically connected to energy storage device and magnetic levitation motor 1. The electrical energy generated by generator 7 can be input into energy storage device for storage or directly input into magnetic levitation motor 1 for power supply. Furthermore, the electrical connection between energy storage device and magnetic levitation motor 1 allows the electrical energy stored in energy storage device to also be input into magnetic levitation motor 1 for power supply.

[0053] In this system, when sudden changes occur in operating conditions, such as blockage at the output of the magnetic levitation centrifugal compressor system or a sudden power outage, the bypass regulating valve 4 is opened to input the high-pressure working fluid into the turbine 5, thus preventing a sharp increase in pressure at the output of the centrifugal compressor 2. Simultaneously, the turbine 5 and generator 7 can convert the energy of the high-pressure working fluid into electrical energy, which can be stored in an energy storage device or supplied to the magnetic levitation motor 1. This achieves energy recovery and utilization while preventing sudden power outages to the magnetic levitation motor 1, thereby improving the safety of the magnetic levitation centrifugal compressor system.

[0054] Optionally, in this embodiment, the magnetic levitation centrifugal compression system further includes a mixing buffer 14, which is connected between the output of the turbine 5 and the input of the centrifugal compressor 2. Specifically, the output of the mixing buffer 14 is connected to the input of the centrifugal compressor 2, and the mixing buffer 14 has a first input and a second input. The first input is connected to the output of the turbine 5, and the second input is used to input a low-pressure working fluid into the magnetic levitation centrifugal compression system. The high-pressure working fluid becomes a low-pressure working fluid after doing work in the turbine 5 and is then input into the mixing buffer 14. The externally provided low-pressure working fluid is mixed with the low-pressure working fluid after it has done work in the mixing buffer 14 and then input back into the centrifugal compressor 2, thereby realizing the recycling of the working fluid.

[0055] Furthermore, a check valve 15 is connected between the turbine 5 and the mixing buffer 14. The check valve 15 can constrain the working fluid, so that the working fluid can only flow in the direction from the turbine 5 to the mixing buffer 14, thus avoiding damage to the turbine 5 and the generator 7 caused by reverse flow.

[0056] Optionally, the magnetic levitation centrifugal compression system also includes a temperature transmitter 16. The temperature transmitter 16 is connected between the main regulating valve 3 and the centrifugal compressor 2, and can measure the temperature of the output high-pressure working fluid to facilitate monitoring of the system's operating status. Similarly, other measuring instruments such as a pressure transmitter 17 and a flow transmitter 18 can also be installed between the main regulating valve 3 and the centrifugal compressor 2, thereby achieving precise control of the system's operating status through multiple different parameters.

[0057] Preferably, a gearbox 6 is also connected between the turbine 5 and the generator 7, so that the generator 7 can generate electricity at a suitable speed and improve the energy recovery and utilization rate.

[0058] It is understandable that the higher the rotational speed of the centrifugal compressor 2, the greater its compression ratio and the higher its energy utilization rate. Therefore, in this embodiment, the rotor of the centrifugal compressor 2 and the output end of the magnetic levitation motor 1 are preferably connected by a coaxial rigid connection, such as by a flange connection or a welded connection, to maximize transmission efficiency. For example, in this embodiment, the rated frequency of the magnetic levitation motor 1 is 500 Hz, and the rated flow rate of the centrifugal compressor 2 is 100 m³ / s. 3 / h.

[0059] Furthermore, such as Figure 1As shown, the energy storage device includes a supercapacitor bank 10, a first current converter 9, and a second current converter 11. The first current converter 9, supercapacitor bank 10, and second current converter 11 are sequentially connected between the generator 7 and the magnetic levitation motor 1. A first circuit breaker 8 connects the first current converter 9 and the generator 7, and a second circuit breaker 12 connects the second current converter 11 and the magnetic levitation motor 1. When the first circuit breaker 8 is closed and the second circuit breaker 12 is open, the alternating current generated by the generator 7 can be converted into direct current by the first current converter 9 and the electrical energy is input into the supercapacitor bank 10 for storage. When the second circuit breaker 12 is closed, the electrical energy stored in the supercapacitor bank 10 can be output to the magnetic levitation motor 1, ensuring the short-term operation of the magnetic levitation motor 1 and thus preventing the magnetic levitation motor 1 from stopping suddenly and being damaged in the event of a power outage.

[0060] Of course, in some other embodiments, the energy storage device can also use other types of energy storage components such as batteries to achieve the storage and output of electrical energy. Compared with batteries, the supercapacitor pack 10 can achieve extremely fast charging and discharging speeds and efficiency, and has an extremely long cycle life, making it suitable for applications requiring instantaneous high power, fast charging and discharging, and long lifespan.

[0061] Furthermore, a third circuit breaker 13 is connected between the generator 7 and the magnetic levitation motor 1. When the third circuit breaker 13 is closed, the electrical energy generated by the generator 7 can be directly supplied to the magnetic levitation motor 1, and can also ensure the short-term operation of the magnetic levitation motor 1 in the event of a power outage. At the same time, the closing of the third circuit breaker 13 can also prevent overcharging of the energy storage device, thereby protecting the energy storage device.

[0062] This invention also provides a control method for a magnetic levitation centrifugal compression system, capable of controlling the aforementioned magnetic levitation centrifugal compression system to reduce safety risks during sudden changes in operating conditions and improve safety. Specifically, the control method for the magnetic levitation centrifugal compression system includes:

[0063] Power generation steps: Open the bypass regulating valve 4 to input the high-pressure working fluid into the turbine 5 to drive the generator 7 to generate electricity.

[0064] Specifically, when the power generation step is implemented, the high-pressure working fluid will not remain continuously between the main regulating valve 3 and the centrifugal compressor 2, thus avoiding the phenomenon of a sharp increase in pressure or a sharp increase in rotor rotation resistance at the output end of the centrifugal compressor 2, which helps to avoid explosion or mechanical damage.

[0065] Energy storage step: Input the electrical energy generated by generator 7 into the energy storage device for storage.

[0066] Specifically, when implementing the energy storage step, closing the first circuit breaker 8 allows electrical energy to be input into the energy storage device for storage, thereby achieving the effect of energy recovery.

[0067] Power supply step: The electrical energy generated by the generator 7 and / or the electrical energy stored in the energy storage device is supplied to the magnetic levitation motor 1.

[0068] Specifically, in the power supply step, it is possible to either close only the second circuit breaker 12 to supply the stored electrical energy to the magnetic levitation motor 1, or close only the first circuit breaker 8 and the second circuit breaker 12 to supply the generated electrical energy (and the stored electrical energy) to the magnetic levitation motor 1 through the storage device, or close only the third circuit breaker 13 to directly supply the electrical energy generated by the generator 7 to the magnetic levitation motor 1. This invention does not limit the specific states of the first circuit breaker 8, the second circuit breaker 12, and the third circuit breaker 13; as long as the electrical energy supply to the magnetic levitation motor 1 is achieved under specific states, it falls within the scope of the power supply step protected by this invention.

[0069] Through the aforementioned power generation, energy storage, and power supply steps, the high-pressure working fluid can be input into turbine 5, preventing a sharp increase in pressure at the output of centrifugal compressor 2. Simultaneously, the combination of these steps converts the energy of the high-pressure working fluid into electrical energy, which can be stored in an energy storage device or supplied to the magnetic levitation motor 1. This achieves energy recovery and utilization while preventing sudden power outages of the magnetic levitation motor 1, thereby improving the safety of the magnetic levitation centrifugal compression system.

[0070] For example, when the magnetic levitation centrifugal compression system is started, the magnetic levitation motor 1 is started by an external power supply, and the main regulating valve 3 is closed while the bypass regulating valve 4 is opened to implement the above-mentioned power generation, energy storage, and power supply steps. At this time, the magnetic levitation motor 1 drives the centrifugal compressor 2 to work, and all the high-pressure gas enters the turbine 5 to do work, driving the generator 7 to generate electricity. Part of the electrical energy generated by the generator 7 supplies power to the magnetic levitation motor 1, and the other part charges the energy storage device. The centrifugal compressor 2 can gradually increase the output pressure and flow rate of the high-pressure working fluid, and can also realize the recovery and utilization of energy, thereby reducing energy waste. Optionally, when the energy storage device is fully charged, the first circuit breaker 8 (and the second circuit breaker 12) can be disconnected, and only the third circuit breaker 13 can be closed, so that only electrical energy is output to the magnetic levitation motor 1, avoiding overcharging.

[0071] More specifically, when the magnetic levitation centrifugal compression system is started, the main regulating valve 3 is first adjusted to the closed state, then the bypass regulating valve 4 is opened to the fully open state, and then the magnetic levitation motor 1 is started by external power supply, so that the centrifugal compressor 2 can operate. After the high-pressure working fluid leaves the centrifugal compressor 2, it flows into the turbine 5 through the bypass regulating valve 4 to do work. The exhaust gas after doing work enters the mixing buffer 14 and mixes with the new low-pressure working fluid entering the mixing buffer 14 before entering the centrifugal compressor 2 for compression.

[0072] The high-voltage power output drives the generator 7 via turbine 5 and gearbox 6 to generate electricity. At this time, the first circuit breaker 8 and the third circuit breaker 13 are closed, while the second circuit breaker 12 is open. The current splits into two paths: one flows into the magnetic levitation motor 1 to supply power, and the other flows into the energy storage device to charge it. When the energy storage device is fully charged, the first circuit breaker 8 is opened, leaving only the third circuit breaker 13 closed.

[0073] By detecting the parameters of the high-pressure working fluid using the pressure transmitter 17 and flow transmitter 18, once the high-pressure working fluid reaches the preset pressure and preset flow rate, the main regulating valve 3 can be gradually opened to output the high-pressure working fluid from the main regulating valve 3 to the outside of the system. Simultaneously, based on the flow or pressure requirements of the high-pressure working fluid, the bypass regulating valve 4 can be gradually closed to stop the power generation process until the high-pressure working fluid is completely output from the main regulating valve 3 to the outside of the system.

[0074] Through the above control process, the system can be started smoothly while the high-pressure working fluid is kept flowing, avoiding the phenomenon of rapid pressure changes during the opening of the main regulating valve 3, and avoiding energy waste during the start-up process, thus achieving both smooth start-up and energy recovery.

[0075] Similarly, when the magnetic levitation centrifugal compression system needs to be shut down normally, the main regulating valve 3 is gradually closed, and the bypass regulating valve 4 is gradually opened to implement the power generation, energy storage, and power supply steps. When the main regulating valve 3 is fully closed, the working fluid flows completely within the system. At this point, the operating frequency of the magnetic levitation motor 1 is gradually reduced until it stops. The power generation step continuously consumes energy within the system to gradually reduce the working fluid flow rate, achieving a smooth decrease in the speed of the centrifugal compressor 2 and the magnetic levitation motor 1. Finally, disconnecting the first circuit breaker 8 and closing the bypass regulating valve 4 smoothly completes the normal shutdown process of the magnetic levitation centrifugal compression system, avoiding rapid changes in pressure or stress during shutdown and reducing energy waste during shutdown.

[0076] Furthermore, when the magnetic levitation centrifugal compression system encounters an emergency, such as a sudden power outage, the main regulating valve 3 is gradually closed, the bypass regulating valve 4 is gradually opened, and the aforementioned power generation, energy storage, and power supply steps are implemented. At this time, the energy storage device supplies power to the magnetic levitation motor 1, maintaining its normal operation for a short period and preventing sudden shutdown due to loss of power supply. The power generation step also continuously consumes energy within the system to gradually reduce the working fluid flow rate, achieving a smooth decrease in the speed of the centrifugal compressor 2 and the magnetic levitation motor 1. Finally, when the main regulating valve 3 is fully closed, the operating frequency of the magnetic levitation motor 1 can be further gradually reduced until it completely stops. After the magnetic levitation motor 1 completely stops, the first circuit breaker 8, the second circuit breaker 12, and the third circuit breaker 13 are disconnected to complete the power outage shutdown procedure.

[0077] Compared to normal shutdown, during power outage shutdown, through the power generation and power supply steps, the magnetic levitation motor 1 can maintain normal operation while picking up external power supply, thereby controlling and gradually reducing its operating frequency, avoiding mechanical damage caused by sudden changes, and improving the safety of the entire system.

[0078] In some embodiments, when it is necessary to increase the output flow rate of the high-pressure working fluid, if the power generation step is still in progress, i.e., the bypass regulating valve 4 is still open, then without changing the operating frequency of the magnetic levitation motor 1, the output flow rate of the high-pressure working fluid can be increased by reducing the opening of the bypass regulating valve 4. This allows the magnetic levitation motor 1 to output high-pressure working fluid at different flow rates at a fixed operating frequency, which is beneficial for maintaining the magnetic levitation motor 1 at its optimal operating frequency. Of course, if the bypass regulating valve 4 is already closed, then the operating frequency of the magnetic levitation motor 1 needs to be further increased until the output flow rate of the high-pressure working fluid meets the requirements.

[0079] When the system needs to reduce the flow rate of the high-pressure working fluid, if the operating frequency of the magnetic levitation motor 1 is higher than its safe frequency (e.g., 425 Hz), the flow rate can be regulated by gradually reducing the operating frequency of the magnetic levitation motor 1. If the operating frequency of the magnetic levitation motor 1 has already been reduced to the safe frequency, and further reduction of the system's output high-pressure working fluid flow rate is still required, the flow rate of the high-pressure working fluid output from the main regulating valve 3 can be further reduced by gradually opening the bypass regulating valve 4. At this time, a portion of the high-pressure working fluid will pass through the bypass regulating valve 4, through the turbine 5 and the mixing buffer 14, and re-enter the centrifugal compressor 2. Furthermore, the high-pressure working fluid can also drive the generator 7 to perform work, thereby selectively achieving the aforementioned energy storage and power supply steps.

[0080] Optionally, in this embodiment, when the amount of electricity in the energy storage device is higher than 80% of its rated capacity, the first circuit breaker 8 remains open, allowing the generator 7 to directly supply power to the magnetic levitation motor 1, thus avoiding problems such as overcharging and breakdown. When the amount of electricity in the energy storage device is lower than 80% of its rated capacity, the energy storage step and the power supply step can be performed simultaneously during the power generation step, that is, a portion of the electricity is input into the energy storage device for storage, and a portion of the electricity is supplied to the magnetic levitation motor 1.

[0081] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0082] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A magnetic levitation centrifugal compression system, characterized in that, include: Centrifugal compressor (2), which is capable of compressing low-pressure working fluid into high-pressure working fluid and outputting it; A magnetic levitation motor (1) is connected to the centrifugal compressor (2) in a transmission manner; The main regulating valve (3) is connected to the output end of the centrifugal compressor (2). The output end of the main regulating valve (3) is used to output the high-pressure working fluid to the magnetic levitation centrifugal compression system. A bypass regulating valve (4) is provided, with its input end connected to the output end of the centrifugal compressor (2); Turbine (5), the input end of the turbine (5) and the output end of the bypass regulating valve (4) are connected; A generator (7) is connected to the turbine (5) in a transmission manner; An energy storage device is electrically connected between the generator (7) and the magnetic levitation motor (1). The high-pressure working fluid can drive the generator (7) through the turbine (5) to selectively supply power to at least one of the energy storage device and the magnetic levitation motor (1). The energy storage device can supply power to the magnetic levitation motor (1).

2. The magnetic levitation centrifugal compression system according to claim 1, characterized in that, Also includes: A mixing buffer (14) is provided, the output of which is connected to the input of the centrifugal compressor (2). The mixing buffer (14) has a first input and a second input. The first input is connected to the output of the turbine (5), and the second input is used to input the low-pressure working fluid into the magnetic levitation centrifugal compression system.

3. The magnetic levitation centrifugal compression system according to claim 2, characterized in that, Also includes: Check valve (15) is connected between the turbine (5) and the mixing buffer (14).

4. The magnetic levitation centrifugal compression system according to claim 1, characterized in that, Also includes: Temperature transmitter (16), the temperature transmitter (16) is connected between the main regulating valve (3) and the centrifugal compressor (2); And / or, A pressure transmitter (17) is connected between the main regulating valve (3) and the centrifugal compressor (2); and / or, A flow transmitter (18) is connected between the main regulating valve (3) and the centrifugal compressor (2); and / or, The gearbox (6) is drive-connected between the turbine (5) and the generator (7).

5. The magnetic levitation centrifugal compression system according to claim 1, characterized in that, The rotor of the centrifugal compressor (2) and the output end of the magnetic levitation motor (1) are rigidly connected coaxially.

6. The magnetic levitation centrifugal compression system according to claim 1, characterized in that, The energy storage device includes a supercapacitor bank (10), a first current converter (9), and a second current converter (11). The first current converter (9), the supercapacitor bank (10), and the second current converter (11) are connected sequentially between the generator (7) and the magnetic levitation motor (1). A first circuit breaker (8) is connected between the first current converter (9) and the generator (7). A second circuit breaker (12) is connected between the second current converter (11) and the magnetic levitation motor (1). A third circuit breaker (13) is connected between the generator (7) and the magnetic levitation motor (1).

7. A control method for a magnetic levitation centrifugal compression system, implemented in any one of claims 1-6, characterized in that, The control method for the magnetic levitation centrifugal compression system includes: Power generation steps: Open the bypass regulating valve (4) and input the high-pressure working fluid into the turbine (5) to drive the generator (7) to generate electricity; Energy storage step: Input the electrical energy generated by the generator (7) into the energy storage device for storage; Power supply steps: The electrical energy generated by the generator (7) and / or the electrical energy stored in the energy storage device are supplied to the magnetic levitation motor (1).

8. The control method for the magnetic levitation centrifugal compression system according to claim 7, characterized in that, When the magnetic levitation centrifugal compression system is started, the main regulating valve (3) is closed, the magnetic levitation motor (1) is started, and the power generation step, the energy storage step and the power supply step are implemented; when the high-pressure working fluid reaches the preset pressure and preset flow rate, the main regulating valve (3) is gradually opened, and the bypass regulating valve (4) is gradually closed.

9. The control method for the magnetic levitation centrifugal compression system according to claim 7, characterized in that, When the magnetic levitation centrifugal compression system is powered off and shut down, the main regulating valve (3) is gradually closed, and the bypass regulating valve (4) is gradually opened simultaneously to implement the power generation step, and then the energy storage step, the power supply step, or the energy storage step and the power supply step are implemented.

10. The control method for the magnetic levitation centrifugal compression system according to claim 7, characterized in that, When the real-time frequency of the magnetic levitation motor (1) drops to a safe frequency and it is necessary to reduce the flow rate of the high-pressure working fluid output by the magnetic levitation centrifugal compression system, the bypass regulating valve (4) is opened to input a portion of the high-pressure working fluid into the turbine (5) to drive the generator (7) to generate electricity and supply power to the magnetic levitation motor (1).

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