Anti-surge backflow control method and system of a magnetic levitation air compressor

Abstract

The application provides a method and system for preventing surge and reflux control of a magnetic suspension air compressor, comprising: a two-stage outlet pipeline of the magnetic suspension air compressor is connected with a one-stage inlet pipeline through a multi-path bypass pipeline, at least a first vent valve, at least one second vent valve and a butterfly valve are arranged in parallel on the multi-path bypass pipeline, comprising: obtaining an operating state parameter of the magnetic suspension air compressor, the operating state parameter is used to represent the pressure of the pipeline of the magnetic suspension air compressor; determining an operating condition point according to the operating state parameter; the operating condition point is used to represent the inlet gas volume flow of the one-stage inlet pipeline and the pressure of the two-stage outlet pipeline; and controlling the opening and closing of the first vent valve, the at least one second vent valve and the butterfly valve based on the comparison result of the operating condition point and at least two surge early warning lines. Therefore, the device efficiency can be improved and the energy consumption can be reduced on the basis of preventing the magnetic suspension air compressor from surging.

Description

Technical Field

[0001] This application relates to the field of magnetic levitation air compressor technology, and in particular to a method and system for anti-surge backflow control of magnetic levitation air compressors. Background Technology

[0002] Surge is a common system phenomenon in magnetic levitation centrifugal air compressors. When the compressor flow rate is less than its limit flow rate, the operating point appears in the unstable region, resulting in strong, periodic back-and-forth airflow. This leads to increased noise and blade stress, generating significant impact forces on the impeller and its connecting components. When these forces increase to a certain level, they can cause the rotating and stationary parts of the air compressor to break, or even destroy the entire air compressor and piping system. Therefore, preventing air compressor surge and ensuring its safe and reliable operation is of paramount importance.

[0003] Anti-surge venting valve is a widely used device in magnetic levitation centrifugal air compressors to prevent air compressor surge. By installing a venting valve on the machine's outlet pipeline, when the air compressor flow rate decreases to close to the surge flow rate, the venting valve is opened automatically or manually, causing the air compressor outlet pressure to drop immediately and the air compressor flow rate to increase.

[0004] Current anti-surge venting valve devices are generally quite simple. When the fan outlet flow rate is lower than the limit flow rate, the valve is fully opened manually or automatically. Although this can prevent surge from occurring, it also releases the gas that has gained energy through the impeller, which reduces the efficiency of the entire device and increases energy consumption. Summary of the Invention

[0005] This application provides a surge prevention and backflow control method and system for a magnetic levitation air compressor, in order to solve the technical problem that current surge prevention methods reduce the efficiency of the device and increase energy consumption.

[0006] To solve the above-mentioned technical problems, this application is implemented as follows:

[0007] In a first aspect, embodiments of this application provide a method for preventing surge and backflow control of a magnetic levitation air compressor. The secondary outlet pipeline and the primary inlet pipeline of the magnetic levitation air compressor are connected by multiple bypass pipelines. Each of the multiple bypass pipelines is equipped with at least one first vent valve, at least one second vent valve, and a butterfly valve connected in parallel. The method for preventing surge and backflow control of the magnetic levitation air compressor includes:

[0008] The operating status parameters of the magnetic levitation air compressor are obtained, and the operating status parameters are used to characterize the pressure of the pipeline of the magnetic levitation air compressor.

[0009] The operating condition point is determined based on the operating status parameters; wherein, the operating condition point is used to characterize the inlet gas volume flow rate of the first-stage intake pipeline and the pressure of the second-stage outlet pipeline;

[0010] The opening and closing of the first vent valve, the at least one second vent valve, and the butterfly valve are controlled based on the comparison results between the operating condition point and at least two surge warning lines; wherein the at least two surge warning lines are surge warning lines with different safety margins established based on the surge shutdown line of the magnetic levitation air compressor.

[0011] Optionally, the operating status parameters include: the pressure of the primary intake pipeline and the pressure of the secondary exhaust pipeline. Determining the operating condition point based on the operating status parameters includes:

[0012] Obtain the differential pressure measured by the differential pressure transmitter in the air inlet section of the magnetic levitation air compressor;

[0013] The mass flow rate of the inlet gas in the first-stage intake pipeline is determined based on the pressure of the first-stage intake pipeline and the pressure difference.

[0014] Calculate the volumetric flow rate of the inlet gas based on the mass flow rate and density of the inlet gas in the first-stage intake pipeline;

[0015] The operating condition point is determined based on the inlet gas volumetric flow rate and the pressure of the secondary outlet pipeline.

[0016] Optionally, the mass flow rate of the inlet gas in the first-stage intake pipeline is determined by the following formula:

[0017]

[0018] The volumetric flow rate of the inlet gas is determined by the following formula based on the mass flow rate and density of the inlet gas in the primary intake pipeline:

[0019]

[0020] in, The mass flow rate of the inlet gas in the first-stage intake pipeline; Here is the boundary layer correction factor; A is the inlet cross-sectional area; The pressure of the first-stage intake pipe; The pressure difference; The adiabatic coefficient; The inlet gas volumetric flow rate; The constant of the medium gas; This refers to the first-stage intake pressure under standard operating conditions. This refers to the temperature of the first-stage intake manifold under standard operating conditions. The density of the imported gas is given.

[0021] Optionally, before the step of controlling the opening and closing of the first vent valve, the at least one second vent valve, and the butterfly valve based on the comparison result between the operating condition point and at least two surge warning lines, the following may be included:

[0022] Obtain at least two reference surge points for the magnetic levitation air compressor;

[0023] The surge stop line is determined using at least two of the aforementioned reference surge points;

[0024] The coordinate points on the surge stop line are transformed according to different safety margins to generate corresponding early warning point sets, wherein each safety margin corresponds to one early warning point set.

[0025] The set of warning points is fitted to obtain multiple surge warning lines, which include a first surge warning line, a second surge warning line, and a third surge warning line. The margin of the first surge warning line is greater than the margin of the second surge warning line, and the margin of the second surge warning line is greater than the margin of the third surge warning line.

[0026] Optionally, controlling the opening and closing of the first vent valve, the at least one second vent valve, and the butterfly valve based on the comparison results between the operating point and at least two surge warning lines includes at least one of the following:

[0027] When the operating condition point is located to the right of the first surge warning line, the butterfly valve is controlled to close.

[0028] When the operating condition point is located to the left of the first surge warning line and to the right of the third surge warning line, the opening of the butterfly valve is adjusted so that the operating pressure of the magnetic levitation air compressor remains unchanged at the target value during the process of the operating condition point moving from the first surge warning line to the third surge warning line.

[0029] When the operating condition point is located to the left of the third surge warning line, the butterfly valve is fully opened.

[0030] When the operating condition point is located to the right of the second surge warning line, the second vent valve and the first vent valve are not opened.

[0031] When the operating condition point is located to the left of the second surge warning line and to the right of the third pressure surge warning line, the second vent valve is controlled to open; when the operating condition point is located to the left of the third surge warning line and to the right of the surge shutdown line, the first vent valve is controlled to open.

[0032] Optionally, controlling the opening and closing of the butterfly valve based on the comparison results between the operating condition point and at least two surge warning lines includes:

[0033] When the operating condition point is located to the right of the first surge warning line, the butterfly valve is controlled to close.

[0034] When the operating condition point is located to the left of the first surge warning line and to the right of the third surge warning line, the opening of the butterfly valve is adjusted so that the operating pressure of the magnetic levitation air compressor remains unchanged at the target value during the process of the operating condition point moving from the first surge warning line to the third surge warning line.

[0035] When the operating condition point is located to the left of the third surge warning line, the opening degree of the butterfly valve is controlled to be fully open.

[0036] Optionally, controlling the opening and closing of the first vent valve and the at least one second vent valve based on the comparison result between the operating condition point and at least two surge warning lines includes:

[0037] When the operating condition point is located to the right of the second surge warning line, control the second vent valve and the first vent valve to close.

[0038] When the operating condition point is located to the left of the second surge warning line and to the right of the third pressure surge warning line, the second vent valve is controlled to open.

[0039] When the operating condition point is located to the left of the third surge warning line and to the right of the surge shutdown line, the first vent valve is controlled to open, wherein the flow rate of the first vent valve is greater than that of the second vent valve.

[0040] Optionally, after controlling the first vent valve to open, the method further includes:

[0041] If the pressure in the secondary air outlet pipeline increases and the operating point moves to the left of the surge stop line, the magnetic levitation air compressor is controlled to stop.

[0042] Optionally, after the step of obtaining the operating status parameters of the magnetic levitation air compressor, the method further includes:

[0043] Obtain the pressure of the secondary outlet pipeline at two sampling times;

[0044] Based on the pressure of the secondary outlet pipeline at two sampling times, the pressure change rate of the secondary outlet pipeline is determined.

[0045] When the rate of pressure change exceeds the preset rate threshold, the first vent valve is opened, wherein the flow rate of the first vent valve is greater than that of the second vent valve.

[0046] Secondly, embodiments of this application provide a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the method described in the first aspect.

[0047] Thirdly, embodiments of this application provide an anti-surge backflow control system for a magnetic levitation air compressor, the anti-surge backflow control system for the magnetic levitation air compressor comprising:

[0048] The magnetic levitation air compressor body is equipped with a primary air inlet pipe and a secondary air outlet pipe.

[0049] A multi-bypass pipeline, wherein the multi-bypass pipeline is connected between the secondary air outlet pipeline and the primary air inlet pipeline;

[0050] A valve assembly disposed on the multi-bypass pipeline, the valve assembly comprising a first vent valve, at least one second vent valve, and a butterfly valve connected in parallel;

[0051] A detection component is used to detect the operating status parameters of the magnetic levitation air compressor, and the operating status parameters are used to characterize the pressure of the pipeline of the magnetic levitation air compressor.

[0052] The controller is used to determine the operating condition point according to the operating status parameters, and to control the opening and closing of the first vent valve, the at least one second vent valve and the butterfly valve in the valve assembly based on the comparison result of the operating condition point and at least two surge warning lines; wherein, the operating condition point is used to characterize the inlet gas volume flow rate of the first-stage intake pipeline and the pressure of the second-stage outlet pipeline, and the at least two surge warning lines are surge warning lines with different safety margins established based on the surge shutdown line of the magnetic levitation air compressor.

[0053] Optionally, the detection component includes a first pressure sensor disposed on the first-stage intake pipe and a second pressure sensor disposed on the second-stage exhaust pipe.

[0054] Optionally, the diameter of the multi-bypass pipeline is smaller than the diameter of the secondary outlet pipeline; the diameter of the first vent valve is larger than the first preset threshold, the diameter of the second vent valve is smaller than the second preset threshold, and the second preset threshold is smaller than the first preset threshold; at least one second vent valve is connected in parallel at both ends of the butterfly valve.

[0055] Optionally, the controller is also configured to perform the anti-surge backflow control method for a magnetically levitated air compressor as described in the first aspect.

[0056] In this embodiment, by acquiring the pressure of the magnetic levitation air compressor pipeline and determining the operating point that simultaneously characterizes the inlet gas volumetric flow rate and the secondary outlet pressure, the actual operating status of the magnetic levitation air compressor can be more accurately reflected. The operating point is compared with at least two surge warning lines with different safety margins established based on the surge shutdown line, and the opening and closing of the first vent valve, the second vent valve, and the butterfly valve are controlled accordingly. This allows for graded adjustment and early intervention at different stages when the air compressor approaches surge, avoiding delayed control or over-adjustment, and balancing surge protection with operating efficiency. This significantly improves the real-time performance and reliability of anti-surge control, effectively avoids unexpected shutdowns caused by surge, enhances the stability of the magnetic levitation air compressor operation, extends equipment lifespan, and improves operating efficiency while reducing energy consumption. Attached Figure Description

[0057] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings:

[0058] Figure 1 A flowchart of an anti-surge backflow control method for a magnetic levitation air compressor provided in this application embodiment;

[0059] Figure 2 A schematic diagram showing the relationship between the inlet gas volume flow rate of the primary intake pipeline and the pressure of the secondary outlet pipeline of a magnetic levitation air compressor provided in this application embodiment;

[0060] Figure 3 This is a schematic diagram of an anti-surge backflow control system for a magnetic levitation air compressor provided in an embodiment of this application. Detailed Implementation

[0061] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0062] Figure 1 This application illustrates a method for preventing surge and backflow control in a magnetic levitation air compressor, as provided in an embodiment of the present application. Figure 1 As shown, the method includes:

[0063] Step S101: Obtain the operating status parameters of the magnetic levitation air compressor;

[0064] Operating status parameters are used to characterize the pressure in the pipeline of the magnetic levitation air compressor;

[0065] Step S102: Determine the operating condition point based on the operating status parameters;

[0066] Among them, the operating condition point is used to characterize the inlet gas volume flow rate of the first-stage intake pipeline and the pressure of the second-stage outlet pipeline;

[0067] Step S103: Based on the comparison results between the operating condition point and at least two surge warning lines, control the opening and closing of the first vent valve, at least one second vent valve and the butterfly valve.

[0068] Among them, at least two surge warning lines are established based on the surge shutdown line of the magnetic levitation air compressor, each with a different safety margin. The secondary outlet pipeline and the primary inlet pipeline of the magnetic levitation air compressor are connected via multiple bypass pipelines. Each bypass pipeline is equipped with at least one parallel first vent valve, at least one second vent valve, and a butterfly valve.

[0069] In this embodiment, by constructing a multi-bypass pipeline connecting the secondary outlet pipeline and the primary inlet pipeline of the magnetic levitation air compressor, the gas from the secondary outlet pipeline can flow back to the primary inlet pipeline through the multi-bypass pipeline, thereby forming a controllable return channel in structure.

[0070] In this embodiment, the flow rates of the first vent valve and the second vent valve can be different, thus achieving precise regulation at both low and high flow rates. Of course, the flow rates of the first vent valve and the second vent valve can also be the same, for time-sharing or range-sharing control, or for simultaneous opening to increase venting efficiency. The specific method can be determined based on actual conditions, and this embodiment does not limit this.

[0071] In this embodiment, the butterfly valve can be used to precisely control the opening degree and adjust the flow rate with high precision according to the linear characteristics; the vent valve can be a quick-opening valve, which can be opened and closed quickly, and can be opened in time to vent during surge warning.

[0072] In this embodiment, the first vent valve, at least one second vent valve, and the butterfly valve can be connected in parallel. It is understood that multiple valves can be connected in series on a single bypass return line, or more bypass return lines can be connected in parallel. The specific configuration can be determined based on the actual situation, and this embodiment does not limit this.

[0073] In this embodiment, the operating status parameters of the magnetic levitation air compressor can be measured in real time and stored at a preset location, and retrieved from the preset location when needed. Alternatively, they can be directly transmitted to the controller for processing and judgment after real-time measurement. The specific method can be determined according to the actual situation, and this embodiment does not limit this.

[0074] In this embodiment, the operating status parameters of the magnetic levitation air compressor can be used to characterize the pressure of the magnetic levitation air compressor pipeline. The operating status parameters of the magnetic levitation air compressor may include at least one of the following: pipeline pressure, inlet gas volumetric flow rate, gas temperature, and the rotational speed of the magnetic levitation air compressor. In some embodiments, this may include the pressure of a primary intake pipeline and the pressure of a secondary outlet pipeline. The pressure of the primary intake pipeline and the pressure of the secondary outlet pipeline can be obtained by measuring with a pressure sensor or calculated based on other operating parameters such as flow rate. The specific parameters can be determined according to actual conditions, and this embodiment does not limit this.

[0075] In this embodiment, the operating point refers to a characteristic point used to characterize the current operating position of the air compressor. The operating point at least reflects the correspondence between the primary inlet gas volume flow rate and the secondary outlet pressure. The method for determining the operating point will differ depending on the operating state parameters of the magnetic levitation air compressor. For example, the operating state parameters of the magnetic levitation air compressor can be directly converted into a two-dimensional coordinate point, or the primary inlet gas volume flow rate and the secondary outlet pressure can be calculated based on the operating state parameters of the magnetic levitation air compressor to obtain the operating point. Of course, it is understood that other possible methods can also be used to determine the operating point; the specific method can be determined according to the actual situation, and this specification does not limit this aspect.

[0076] In this embodiment, the surge shutdown line refers to the boundary line at which the compressor needs to enter shutdown protection when it is close to the instability boundary and continues to deteriorate; the surge warning line refers to the warning boundary formed by shifting the surge shutdown line outward to the safe side according to a pre-set safety margin. The safety margin refers to the control margin reserved in advance relative to the surge shutdown boundary. Its purpose is to enable the controller to start adjustment and protection at a more forward position, rather than waiting until the operating point is actually close to the instability boundary.

[0077] In this embodiment, while the unit is operating normally, its current operating status is continuously monitored. When a change in the operating status towards surge risk is detected, timely intervention is implemented through backflow control. Specifically, the controller first receives the pressure of the magnetic levitation air compressor pipeline collected by the detection component, determines the current operating point based on this, and then compares this operating point with at least two surge warning lines. Based on the comparison results, the controller controls the opening and closing or changes in the opening degree of the first vent valve, the second vent valve, and the butterfly valve, thereby adjusting the amount of air flowing back from the secondary outlet side to the primary inlet side. By setting at least two surge warning lines with different safety margins, and controlling the opening and closing of the first vent valve, at least one second vent valve, and the butterfly valve connected in parallel on multiple bypass pipelines accordingly, graded adjustment and early intervention can be implemented at different stages when the air compressor approaches surge, avoiding delayed control or over-adjustment, and balancing surge protection and operating efficiency.

[0078] In one possible implementation, the operating status parameters include: the pressure of the primary intake pipeline and the pressure of the secondary exhaust pipeline. Determining the operating point based on the operating status parameters may include:

[0079] Obtain the differential pressure measured by the differential pressure transmitter at the air inlet section of the magnetic levitation air compressor;

[0080] Determine the mass flow rate of the inlet gas in the first-stage intake pipeline based on the pressure and pressure difference of the first-stage intake pipeline;

[0081] Calculate the volumetric flow rate of the inlet gas based on the mass flow rate and density of the inlet gas in the primary intake pipeline.

[0082] The operating point is determined based on the inlet gas volumetric flow rate and the pressure of the secondary outlet pipeline.

[0083] The mass flow rate of the inlet gas in the first-stage intake pipeline can be determined by the following formula:

[0084]

[0085] The inlet gas volumetric flow rate is determined using the following formula, based on the mass flow rate and density of the inlet gas in the primary intake pipeline:

[0086]

[0087] in, This refers to the mass flow rate of the inlet gas in the primary intake pipeline. Here is the boundary layer correction factor; A is the inlet cross-sectional area; The pressure of the primary intake pipe; It is the pressure difference; The adiabatic coefficient; This refers to the volumetric flow rate of the inlet gas. The constant of the medium gas; This refers to the first-stage intake pressure under standard operating conditions. This refers to the temperature of the first-stage intake manifold under standard operating conditions. This represents the density of the imported gas.

[0088] In this embodiment, , It can be the theoretical value under standard operating conditions. In some implementations, if the pipeline is equipped with measuring elements such as pressure sensors or temperature sensors, the actual measured value can also be used. The specific value can be determined according to the actual situation. This specification does not limit this.

[0089] In this possible implementation, the differential pressure measured by the inlet section differential pressure transmitter can refer to the pressure difference formed before and after the gas flows through the inlet section measurement structure. This pressure difference corresponds to the gas flow rate through this location and can be used as a basic parameter for gas flow rate calculation. The mass flow rate of the inlet gas in the primary intake pipeline refers to the mass of gas entering the primary intake pipeline per unit time, used to reflect the compressor's current actual suction capacity. The volumetric flow rate of the inlet gas refers to the volumetric flow rate of the inlet gas entering the primary intake pipeline per unit time. The combination of the inlet gas volumetric flow rate and the secondary outlet pressure is more suitable for characterizing the compressor's operating status.

[0090] The boundary layer correction factor, inlet cross-sectional area, thermal insulation coefficient, medium gas constant, and parameters such as temperature and pressure under standard operating conditions mentioned in this application can all be preset in conjunction with the equipment structure, medium type, and test calibration results.

[0091] The operating point needs to be established based on parameters that accurately reflect the current operating status of the unit. First, the differential pressure transmitter installed in the inlet section can measure the pressure difference. Then, combined with the pressure of the first-stage inlet pipeline, the mass flow rate of the inlet gas in the first-stage inlet pipeline is determined according to a preset flow conversion relationship. Subsequently, the mass flow rate of the inlet gas in the first-stage inlet pipeline is converted into the volumetric flow rate of the inlet gas based on the inlet gas density. Finally, the operating point is determined together with the pressure of the second-stage outlet pipeline.

[0092] It should be noted that the surge characteristics of magnetic levitation air compressors typically need to be determined based on the combined relationship between flow rate and pressure. By first calculating the mass flow rate of the inlet gas in the primary intake pipeline and then converting it to the volumetric flow rate, the subsequently determined operating point can more closely approximate the actual operating state of the equipment. For example, during the equipment's factory calibration phase, relevant coefficients can be pre-determined based on the established inlet section structure, medium type, and standard operating parameters. During unit operation, the controller only needs to read the primary inlet pressure, differential pressure, and relevant temperature data in real time to dynamically calculate the inlet gas volumetric flow rate and jointly determine the operating point with the secondary outlet pressure. This provides a more reliable basis for subsequent early warning line comparisons and valve control, improving the targeting and accuracy of anti-surge control.

[0093] The following explanation uses a formula. When using surge warning line control, the magnetic levitation air compressor operates at a constant speed. As the pressure in the secondary outlet line increases, the air intake volume in the primary inlet line decreases. The system monitors the pressure in the secondary outlet line. Simultaneously calculate the inlet gas volumetric flow rate. .

[0094]

[0095]

[0096] in, The mass flow rate of the inlet gas in the primary intake pipeline is kg / s; Here, A is the boundary layer correction factor; A is the inlet cross-sectional area in m². 2 ; The pressure of the first-stage intake pipe is Pa; The differential pressure (Pa) measured by the differential pressure transmitter in the air inlet section; The adiabatic coefficient; The inlet gas volumetric flow rate is m³ / min; The constant of the medium is J / (kg*K); The first-stage intake pressure under standard operating conditions is kPa. The temperature K of the first-stage intake manifold under standard operating conditions. This represents the density of the imported gas.

[0097] Therefore, it can more accurately reflect the actual operating status between the inlet gas volume flow rate and the secondary outlet pipeline pressure of the magnetic levitation air compressor, thus providing a reliable data basis for subsequent comparison with the operating condition point, surge shutdown line and various surge warning lines, making the anti-surge backflow control method more feasible and accurate.

[0098] In one possible implementation, before controlling the opening and closing of the first vent valve, at least one second vent valve, and the butterfly valve based on the comparison results between the operating point and at least two surge warning lines, the method may further include: acquiring at least two reference surge operating points of the magnetic levitation air compressor; determining a surge shutdown line using the at least two reference surge operating points; performing coordinate transformation processing on the coordinate points on the surge shutdown line according to different safety margins to generate corresponding warning point sets, wherein each safety margin corresponds to a warning point set; and performing fitting processing on the warning point sets, wherein the surge warning line obtained by fitting can be a straight line, a curve, or other irregular curves, depending on the distribution of the warning point sets, and the specific type can be determined according to the actual situation, which is not limited in this embodiment.

[0099] Optionally, the multiple surge warning lines may include: a first surge warning line, a second surge warning line, and a third surge warning line, wherein the margin of the first surge warning line is greater than the margin of the second surge warning line, and the margin of the second surge warning line is greater than the margin of the third surge warning line. In some embodiments, more surge warning lines may be included, which can be determined according to the actual situation, and this specification does not limit this.

[0100] In other embodiments, multiple surge warning lines may include two, such as a first surge warning line and a third surge warning line. In this case, when the operating point exceeds the first surge warning line, adjustment is made via a butterfly valve; when the operating point further exceeds the third surge warning line, rapid venting is performed directly via a first vent valve, thereby achieving surge protection with a relatively simplified control logic. Of course, the specific number of surge warning lines can be determined according to the actual control accuracy requirements and unit operating characteristics; this embodiment does not limit this.

[0101] The operating condition point needs to be compared with multiple surge warning lines, so these warning lines can be established in advance. To this end, in this possible implementation, at least two benchmark surge condition points can be obtained during equipment factory testing, commissioning, or historical operating data analysis, and these benchmark surge condition points can be used to determine the surge shutdown line. Subsequently, the coordinate points on the surge shutdown line are transformed according to different safety margins to form different sets of warning points, and these sets are fitted to obtain the first surge warning line, the second surge warning line, and the third surge warning line. Multiple warning lines formed in this way better reflect the actual risk changes of the unit under different operating conditions. Alternatively, the surge warning line can be determined during the initial power-on after delivery and stored in a preset location; the specific method can be determined according to the actual situation, and this manual does not impose any limitations on this.

[0102] In one possible implementation, the opening and closing of a first vent valve, at least one second vent valve, and a butterfly valve are controlled based on the comparison results between the operating point and at least two surge warning lines, including at least one of the following:

[0103] When the operating condition point is located to the right of the first surge warning line, it indicates that the current operating state is still far from the surge boundary and the unit is in the safe operating range. At this time, there is no need to adjust the backflow through the bypass pipeline. Therefore, the butterfly valve is closed to avoid unnecessary gas backflow and energy loss.

[0104] When the operating condition point is located to the left of the first surge warning line and to the right of the third surge warning line, it indicates that the operating state has begun to shift towards the surge direction but has not yet entered the high-risk area. At this time, the opening of the butterfly valve can be adjusted so that the operating pressure of the magnetic levitation air compressor remains unchanged at the target value during the process of the operating condition point moving from the first surge warning line to the third surge warning line.

[0105] When the operating condition point is located to the left of the third surge warning line, it indicates that the operating state is close to the surge boundary, and the regulating capacity of the butterfly valve may not be sufficient to meet the anti-surge requirements. Therefore, the butterfly valve should be fully opened.

[0106] When the operating condition point is located to the right of the second surge warning line, it indicates that the operating state has not yet entered the area where rapid venting is required through the vent valve. At this time, the second vent valve and the first vent valve should not be opened.

[0107] When the operating point is to the left of the second surge warning line and to the right of the third pressure surge warning line, it indicates that the operating condition has entered a medium-risk area. Relying solely on butterfly valve adjustment may not be sufficient to suppress the surge trend. Therefore, the second vent valve is opened. When the operating point is to the left of the third surge warning line and to the right of the surge shutdown line, it indicates that the operating condition is very close to the surge limit. Greater venting capacity is required for emergency intervention. Therefore, the first vent valve is opened, and the large-diameter vent valve is used to quickly vent the air to bring the operating point back to a safe area as soon as possible.

[0108] In one possible implementation, controlling the opening and closing of the butterfly valve based on the comparison result between the operating point and at least two surge warning lines may include:

[0109] When the operating point is located to the right of the first surge warning line, the control butterfly valve is closed. At this time, the unit is operating in the safe zone. Keeping the butterfly valve closed can reduce unnecessary gas backflow and help maintain the system's operating efficiency.

[0110] When the operating point is located to the left of the first surge warning line and to the right of the third surge warning line, adjust the opening of the butterfly valve so that the operating pressure of the magnetic levitation air compressor remains unchanged at the target value during the process of the operating point moving from the first surge warning line to the third surge warning line.

[0111] When the operating condition point is located to the left of the third surge warning line, the control butterfly valve is fully open. At this time, the butterfly valve has reached its maximum regulating capacity. If the operating condition continues to deteriorate, the vent valve needs to intervene further.

[0112] In one possible implementation, controlling the opening and closing of the first vent valve and at least one second vent valve based on the comparison results between the operating point and at least two surge warning lines may include:

[0113] When the operating point is located to the right of the second surge warning line, the second vent valve and the first vent valve are closed. Within this range, the adjustment capacity of the butterfly valve is sufficient to cope with the current surge risk, and there is no need to start the vent valve for additional venting operations.

[0114] When the operating condition point is located to the left of the second surge warning line and to the right of the third pressure surge warning line, the second vent valve is opened. The second vent valve has a relatively small diameter, and its opening can provide additional moderate venting on the basis of butterfly valve regulation, thereby further increasing the return flow and strengthening the suppression of the operating state shifting towards surge.

[0115] When the operating condition point is located to the left of the third surge warning line and to the right of the surge shutdown line, the first vent valve is opened, wherein the flow rate of the first vent valve is greater than that of the second vent valve.

[0116] It should be noted that this possible implementation provides detailed control logic for comparing the operating point with the surge warning line and controlling the valves on the multi-bypass return pipeline based on the comparison results. This can be categorized into the following cases:

[0117] The operating point is compared with the first and third surge warning lines in a preset coordinate system: when the operating point is to the right of the first surge warning line, the control butterfly valve is not opened; when the operating point is to the left of the first surge warning line and to the right of the third surge warning line, the target value of the operating pressure of the magnetic levitation air compressor is set, and the opening of the butterfly valve is adjusted so that the operating pressure remains unchanged at the target value as the operating point moves from the first surge warning line to the third surge warning line; when the operating point is to the left of the third surge warning line, the control butterfly valve is fully opened to maximize the backflow regulation capability.

[0118] The operating point is compared with the second and third surge warning lines: when the operating point is to the right of the second surge warning line, the second and first vent valves are kept closed; when the operating point is to the left of the second surge warning line and to the right of the third pressure surge warning line, the second vent valve is opened for moderate venting and backflow regulation; when the operating point is to the left of the third surge warning line and to the right of the surge shutdown line, the first vent valve is opened to intervene in the region closest to the surge limit through large-diameter rapid venting. These two parts of control logic constitute the coordinated hierarchical control relationship between the butterfly valve, the second vent valve, and the first vent valve.

[0119] Therefore, multiple surge warning lines with different safety margins are introduced on top of a single surge shutdown line. This means that anti-surge control no longer relies solely on single-point shutdown protection when approaching the surge limit, but can trigger different levels of control actions at different stages before approaching the surge region. In this way, the operating points of the magnetic levitation air compressor can be managed hierarchically between the first, second, and third surge warning lines. Through a progressively enhanced warning and control strategy, anti-surge control becomes smoother, more controllable, and safer.

[0120] In this embodiment, the gas volume can be adjusted by a butterfly valve when the surge warning is not obvious. When the gas volume is close to the surge condition, it can be vented quickly by a large-diameter vent valve. When the unit is already close to the surge condition, it can be vented quickly by a large-diameter first vent valve in order to bring the operating point back to the safe area as soon as possible. If the above measures are still insufficient to prevent the operating condition from deteriorating further, then the shutdown protection will be further implemented.

[0121] For example, if downstream gas consumption suddenly decreases or system resistance increases, the compressor outlet pressure may rise, while the effective flow rate on the inlet side decreases accordingly. In this case, the operating point will move towards the surge boundary. Based on the change in the operating point's position relative to each warning line, the controller gradually changes the valve status on the bypass return path, allowing some compressed gas to flow back from the secondary outlet side to the primary inlet side, thereby readjusting the flow and pressure matching relationship of the unit. Using this method, anti-surge control no longer relies on a single fixed threshold for coarse judgment, but can perform more targeted, tiered adjustments based on the actual operating status of the unit, thus improving the timeliness, stability, and reliability of control.

[0122] The following explanation is based on the formula: The surge pressure operating point is determined according to the air compressor surge test. , and , Based on a certain margin B%, determine the surge pressure warning point. , and , Control the opening of the large-diameter vent valve; determine the surge pressure warning point based on a certain margin C%. , and , Controlling the opening of small-diameter vent valves allows for setting multiple pressure warning points based on the number of small vent valves connected in parallel; the surge pressure warning point is determined based on a certain margin D%. , and , To control the opening degree of the butterfly valve; B is less than C, and C is less than D, which can generally be set to 1%-10%.

[0123]

[0124]

[0125]

[0126]

[0127]

[0128]

[0129] according to , and , Confirm the pressure surge shutdown line:

[0130]

[0131] according to , and , Confirm the B-pressure surge warning line:

[0132]

[0133] according to , and , Confirm C-pressure surge warning line:

[0134]

[0135] according to , and , Confirm the D-pressure surge warning line:

[0136]

[0137] B (Third Surge Warning Line), C (Second Surge Warning Line), and D (First Surge Warning Line) are pressure surge warning lines and pressure surge shutdown lines, as shown below. Figure 2 As shown.

[0138] In specific application scenarios, as the butterfly valve opening degree increases, the flow rate increases, and the magnetic levitation air compressor moves away from surge conditions. The butterfly valve opening strategy is as follows: when the air compressor's operating point inlet gas volume flow rate... , When operating to the right of the D pressure surge warning line, the butterfly valve does not open; when the air compressor's operating point inlet gas volume flow rate... , When operating between the left side of the pressure surge warning line D and the right side of the pressure surge warning line B, set the operating pressure to k, and increase the opening of the regulating butterfly valve from D to B to maintain the operating pressure k constant; when the air compressor's operating point inlet gas volume flow rate... , When operating to the left of the B-pressure surge warning line, the butterfly valve is 100% open. Opening the vent valve increases the flow rate, moving the magnetic levitation air compressor away from the surge condition. The vent valve opening strategy is: when the inlet gas volumetric flow rate at the air compressor's operating point... , When operating to the right of the C-pressure surge warning line, the vent valve does not open; when the inlet gas volume flow rate at the air compressor operating point... , When the compressor is operating to the left of the C pressure surge warning line and to the right of the B pressure surge warning line, open the small-diameter vent valve; when the air compressor's operating point inlet gas volume flow rate... , When operating to the left of the pressure surge warning line and to the right of the pressure surge shutdown line, open the large-diameter vent valve; even with the large-diameter vent valve open, the pressure in the secondary outlet pipeline still increases, and the inlet gas volumetric flow rate at the air compressor operating point... , When the unit reaches the left side of the pressure surge shutdown line, it will shut down.

[0139] This enables coordinated control based on the different positions of the operating point relative to the first surge warning line, the second surge warning line, the third surge warning line, and the surge shutdown line: when far from the surge area, the valves are kept closed to maintain normal efficiency; when approaching the surge area at different levels, the butterfly valve, the second vent valve, and the first vent valve are gradually opened, so that the return flow and venting volume in the multi-bypass return pipeline are gradually increased. This allows for smooth adjustment through the butterfly valve at an earlier stage, and rapid unloading and forced protection through the second vent valve and the first vent valve when approaching the dangerous operating condition, making the anti-surge control both precise and reliable.

[0140] In one possible implementation, after controlling the opening of the first vent valve, the method further includes: if the pressure of the secondary outlet pipeline increases and the operating point moves to the left of the surge stop line, controlling the magnetic levitation air compressor to stop.

[0141] The opening of the first vent valve does not automatically mean the risk has been eliminated. The controller must continue to monitor the pressure in the secondary outlet pipeline and changes in the operating point. If the pressure in the secondary outlet pipeline continues to increase after the first vent valve has opened, and the operating point has moved to the left of the surge shutdown line, it indicates that even with strong vent protection, the unit has not escaped the trend towards instability. In this case, continuing operation may lead to significant vibration, rapid performance deterioration, or even equipment damage. Therefore, the controller can issue a shutdown command to stop the magnetic levitation air compressor.

[0142] Therefore, when neither butterfly valve regulation nor vent valve protection is sufficient to prevent the risk from escalating further, this embodiment does not forcibly maintain operation but prioritizes equipment safety by shutting down the unit. This helps avoid prolonged operation of the unit on the verge of instability, improving the overall safety and reliability of the unit.

[0143] In one possible implementation, after obtaining the operating status parameters of the magnetic levitation air compressor, the method further includes: obtaining the pressure of the secondary outlet pipeline at two sampling times; determining the pressure change rate of the secondary outlet pipeline based on the pressure at the two sampling times; and controlling the opening of the first vent valve when the pressure change rate exceeds a preset rate threshold, wherein the flow rate of the first vent valve is greater than that of the second vent valve. After obtaining the operating status parameters, the pressure of the secondary outlet pipeline at two sampling times can also be obtained, and the pressure change rate can be determined accordingly. When the pressure change rate exceeds the preset rate threshold, the first vent valve can be directly controlled to open.

[0144] In some real-world operating conditions, surge risk may not evolve slowly but escalate rapidly within a short period. If the conventional process of comparing operating points with warning thresholds is still relied upon for step-by-step processing, the response may be too slow. Therefore, by introducing the rate of pressure change as an auxiliary criterion, the controller can identify the deteriorating trend of the operating condition earlier and activate the first vent valve for rapid protection, thereby enhancing the system's ability to respond to sudden surge risks.

[0145] When using the secondary outlet gas line pressure change rate control, the system monitors the pressure sensor signal in real time and calculates the pressure change rate of the secondary outlet gas line. :

[0146]

[0147] in, The pressure change rate of the secondary outlet pipeline is Pa / s; The pressure of the secondary exhaust pipeline; Let the time be s. During the operation of the magnetic levitation air compressor, when the pressure change rate is... Exceeding the set value The large-diameter vent valve is opened, and some of the high-pressure gas is recovered to the primary intake pipeline through the vent return pipeline, increasing the flow rate and keeping the magnetic levitation air compressor away from surge conditions. It should also be noted that the system simultaneously controls the opening of the vent valve based on the pressure warning line and the pressure change rate of the secondary outlet pipeline, with both strategies executed in parallel.

[0148] By introducing the pressure change rate of the secondary vent pipeline as a dynamic criterion, the anti-surge backflow control method is made sensitive and responsive to rapid changes in operating conditions. In the event of a sudden pressure rise that may rapidly approach surge, the first vent valve can be activated in advance based on the pressure change rate. Thus, in addition to operating in parallel with the graded control strategy based on the early warning line, an independent rapid response path is provided, further improving the timeliness and reliability of anti-surge control.

[0149] In this embodiment, by acquiring operating status parameters such as the pressure of the primary intake pipeline and the pressure of the secondary outlet pipeline, and determining the operating condition point that simultaneously characterizes the inlet gas volumetric flow rate and the secondary outlet pressure, the actual operating status of the magnetic levitation air compressor can be more accurately reflected. The operating condition point is compared with at least two surge warning lines established based on surge shutdown lines and with different safety margins. Based on this comparison, the opening and closing of the first vent valve, the second vent valve, and the butterfly valve are controlled. This allows for graded adjustment and early intervention at different stages when the air compressor approaches surge, avoiding delayed control or over-adjustment, and balancing surge protection with operating efficiency. This significantly improves the real-time performance and reliability of anti-surge control, effectively avoids unexpected shutdowns caused by surge, enhances the stability of the magnetic levitation air compressor operation, extends equipment lifespan, and improves operating efficiency while reducing energy consumption.

[0150] Specifically, the anti-surge backflow control method for a magnetic levitation air compressor shown in the embodiments of this application has the following technical effects:

[0151] 1. By using multiple bypass pipelines to return the high-pressure gas from the compressor outlet to the inlet, the main flow rate of the compressor is kept above the surge threshold, thus avoiding surge caused by excessively low flow rate;

[0152] 2. Direct venting of high-temperature and high-pressure gas will result in energy loss. Recovering high-pressure gas through multiple bypass pipelines can significantly improve system energy efficiency.

[0153] 3. Multiple bypass pipelines enable complete recovery of vented gas, preventing direct discharge of vented gas into the atmosphere. It can be used to treat toxic, flammable, explosive, or economically valuable gases.

[0154] 4. Multiple bypass pipelines can be selected from stainless steel, carbon steel, or composite materials according to the customer's compressed gas (temperature, corrosiveness).

[0155] 5. Direct venting of high-pressure gas will generate high-decibel noise. Multi-bypass pipelines recover high-pressure gas, which significantly reduces the impact of noise on the working environment.

[0156] 6. Venting can cause a sudden drop or fluctuation in system pressure. By connecting multiple bypass pipelines with vent valves and butterfly valves in parallel, the pressure can be smoothly regulated to maintain the stability of venting in the ultra-high-speed magnetic levitation control system.

[0157] Figure 3 This invention illustrates an anti-surge backflow control system for a magnetic levitation air compressor according to an embodiment of this application, such as... Figure 3 As shown, the anti-surge backflow control system of the magnetic levitation air compressor includes:

[0158] The magnetic levitation air compressor body is equipped with a primary air inlet pipe and a secondary air outlet pipe.

[0159] Multiple bypass lines are connected between the secondary exhaust line and the primary intake line;

[0160] A valve assembly is installed on a multi-bypass pipeline. The valve assembly includes a first vent valve, at least one second vent valve, and a butterfly valve connected in parallel.

[0161] The detection component is used to detect the operating status parameters of the magnetic levitation air compressor, and the operating status parameters are used to characterize the pressure of the magnetic levitation air compressor pipeline;

[0162] The controller is used to determine the operating condition point based on the operating status parameters, and to control the opening and closing of the first vent valve, at least one second vent valve and butterfly valve in the valve assembly based on the comparison result of the operating condition point and at least two surge warning lines; wherein, the operating condition point is used to characterize the inlet gas volume flow rate of the first-stage intake pipeline and the pressure of the second-stage outlet pipeline, and the at least two surge warning lines are surge warning lines with different safety margins established based on the surge shutdown line of the magnetic levitation air compressor.

[0163] In one possible implementation, the detection component includes a first pressure sensor disposed on the first-stage intake line and a second pressure sensor disposed on the second-stage exhaust line.

[0164] In one possible implementation, the diameter of the multi-bypass pipeline is smaller than the diameter of the secondary outlet pipeline; the diameter of the first vent valve is larger than the first preset threshold, the diameter of the second vent valve is smaller than the second preset threshold, and the second preset threshold is smaller than the first preset threshold; at least one second vent valve is connected in parallel at both ends of the butterfly valve.

[0165] In one possible implementation, the controller is also used to perform the above-described anti-surge backflow control method for a magnetic levitation air compressor.

[0166] This application also provides a computer-readable storage medium storing a computer program. When executed by a processor, the computer program implements the steps of the anti-surge and backflow control method for a magnetic levitation air compressor as shown in the above embodiments, and achieves the same technical effect. To avoid repetition, it will not be described again here. The computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc.

[0167] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0168] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, 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 is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0169] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A method for preventing surge and backflow control in a magnetic levitation air compressor, characterized in that, The secondary outlet pipeline of the magnetic levitation air compressor is connected to the primary inlet pipeline via a multi-bypass pipeline. Each multi-bypass pipeline is equipped with at least one first vent valve, at least one second vent valve, and a butterfly valve connected in parallel. The anti-surge backflow control method for the magnetic levitation air compressor includes: The operating status parameters of the magnetic levitation air compressor are obtained, and the operating status parameters are used to characterize the pressure of the pipeline of the magnetic levitation air compressor. The operating condition point is determined based on the operating status parameters; wherein, the operating condition point is used to characterize the inlet gas volume flow rate of the first-stage intake pipeline and the pressure of the second-stage outlet pipeline; The opening and closing of the first vent valve, the at least one second vent valve, and the butterfly valve are controlled based on the comparison results between the operating condition point and at least two surge warning lines; wherein the at least two surge warning lines are surge warning lines with different safety margins established based on the surge shutdown line of the magnetic levitation air compressor.

2. The method according to claim 1, characterized in that, The operating status parameters include: the pressure of the primary intake pipeline and the pressure of the secondary exhaust pipeline. Determining the operating condition point based on these operating status parameters includes: Obtain the differential pressure measured by the differential pressure transmitter in the air inlet section of the magnetic levitation air compressor; The mass flow rate of the inlet gas in the first-stage intake pipeline is determined based on the pressure of the first-stage intake pipeline and the pressure difference. Calculate the volumetric flow rate of the inlet gas based on the mass flow rate and density of the inlet gas in the first-stage inlet pipeline; The operating condition point is determined based on the inlet gas volumetric flow rate and the pressure of the secondary outlet pipeline.

3. The method according to claim 2, characterized in that, The mass flow rate of the inlet gas in the primary intake pipeline is determined by the following formula: ； The volumetric flow rate of the inlet gas is determined by the following formula based on the mass flow rate and density of the inlet gas in the primary intake pipeline: ； in, The mass flow rate of the inlet gas in the first-stage intake pipeline; Here is the boundary layer correction factor; A is the inlet cross-sectional area; The pressure of the first-stage intake pipe; The pressure difference; The adiabatic coefficient; The inlet gas volumetric flow rate; The constant of the medium gas; This refers to the first-stage intake pressure under standard operating conditions. This refers to the temperature of the first-stage intake manifold under standard operating conditions. The density of the imported gas is given.

4. The method according to claim 1, characterized in that, Before the step of controlling the opening and closing of the first vent valve, the at least one second vent valve, and the butterfly valve based on the comparison result between the operating condition point and at least two surge warning lines, the method further includes: Obtain at least two reference surge points for the magnetic levitation air compressor; The surge stop line is determined using at least two of the aforementioned reference surge points; The coordinate points on the surge stop line are transformed according to different safety margins to generate corresponding early warning point sets, wherein each safety margin corresponds to one early warning point set. The set of warning points is fitted to obtain multiple surge warning lines, which include a first surge warning line, a second surge warning line, and a third surge warning line. The margin of the first surge warning line is greater than the margin of the second surge warning line, and the margin of the second surge warning line is greater than the margin of the third surge warning line.

5. The method according to claim 4, characterized in that, Controlling the opening and closing of the first vent valve, the at least one second vent valve, and the butterfly valve based on the comparison results between the operating point and at least two surge warning lines includes at least one of the following: When the operating condition point is located to the right of the first surge warning line, the butterfly valve is controlled to close. When the operating condition point is located to the left of the first surge warning line and to the right of the third surge warning line, the opening of the butterfly valve is adjusted so that the operating pressure of the magnetic levitation air compressor remains unchanged at the target value during the process of the operating condition point moving from the first surge warning line to the third surge warning line. When the operating condition point is located to the left of the third surge warning line, the butterfly valve is fully opened. When the operating condition point is located to the right of the second surge warning line, the second vent valve and the first vent valve are not opened. When the operating condition point is located to the left of the second surge warning line and to the right of the third pressure surge warning line, the second vent valve is controlled to open; when the operating condition point is located to the left of the third surge warning line and to the right of the surge shutdown line, the first vent valve is controlled to open.

6. The method according to claim 5, characterized in that, Controlling the opening and closing of the butterfly valve based on the comparison results between the operating condition point and at least two surge warning lines includes: When the operating condition point is located to the right of the first surge warning line, the butterfly valve is controlled to close. When the operating condition point is located to the left of the first surge warning line and to the right of the third surge warning line, the opening of the butterfly valve is adjusted so that the operating pressure of the magnetic levitation air compressor remains unchanged at the target value during the process of the operating condition point moving from the first surge warning line to the third surge warning line. When the operating condition point is located to the left of the third surge warning line, the opening degree of the butterfly valve is controlled to be fully open.

7. The method according to claim 5, characterized in that, Controlling the opening and closing of the first vent valve and the at least one second vent valve based on the comparison results between the operating condition point and at least two surge warning lines includes: When the operating condition point is located to the right of the second surge warning line, control the second vent valve and the first vent valve to close. When the operating condition point is located to the left of the second surge warning line and to the right of the third pressure surge warning line, the second vent valve is controlled to open. When the operating condition point is located to the left of the third surge warning line and to the right of the surge shutdown line, the first vent valve is controlled to open, wherein the flow rate of the first vent valve is greater than that of the second vent valve.

8. The method according to claim 7, characterized in that, After controlling the opening of the first vent valve, the following is also included: If the pressure in the secondary air outlet pipeline increases and the operating point moves to the left of the surge stop line, the magnetic levitation air compressor is controlled to stop.

9. The method according to any one of claims 1-8, characterized in that, After the step of obtaining the operating status parameters of the magnetic levitation air compressor, the method further includes: Obtain the pressure of the secondary outlet pipeline at two sampling times; Based on the pressure of the secondary outlet pipeline at two sampling times, the pressure change rate of the secondary outlet pipeline is determined. When the rate of pressure change exceeds the preset rate threshold, the first vent valve is opened, wherein the flow rate of the first vent valve is greater than that of the second vent valve.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the method as described in any one of claims 1 to 9.

11. A surge-resistant backflow control system for a magnetic levitation air compressor, characterized in that, The anti-surge backflow control system of the magnetic levitation air compressor includes: The magnetic levitation air compressor body is equipped with a primary air inlet pipe and a secondary air outlet pipe. A multi-bypass pipeline, wherein the multi-bypass pipeline is connected between the secondary air outlet pipeline and the primary air inlet pipeline; A valve assembly disposed on the multi-bypass pipeline, the valve assembly comprising a first vent valve, at least one second vent valve, and a butterfly valve connected in parallel; A detection component is used to detect the operating status parameters of the magnetic levitation air compressor, and the operating status parameters are used to characterize the pressure of the pipeline of the magnetic levitation air compressor. The controller is used to determine the operating condition point according to the operating status parameters, and to control the opening and closing of the first vent valve, the at least one second vent valve and the butterfly valve in the valve assembly based on the comparison result of the operating condition point and at least two surge warning lines; wherein, the operating condition point is used to characterize the inlet gas volume flow rate of the first-stage intake pipeline and the pressure of the second-stage outlet pipeline, and the at least two surge warning lines are surge warning lines with different safety margins established based on the surge shutdown line of the magnetic levitation air compressor.

12. The system according to claim 11, characterized in that, The detection component includes a first pressure sensor disposed on the first-stage intake pipe and a second pressure sensor disposed on the second-stage exhaust pipe.

13. The system according to claim 11, characterized in that, The diameter of the multi-bypass pipeline is smaller than the diameter of the secondary outlet pipeline; the diameter of the first vent valve is larger than the first preset threshold, the diameter of the second vent valve is smaller than the second preset threshold, and the second preset threshold is smaller than the first preset threshold; at least one second vent valve is connected in parallel at both ends of the butterfly valve.

14. The system according to claim 11, characterized in that, The controller is also used to execute the anti-surge backflow control method for a magnetic levitation air compressor as described in any one of claims 1-9.

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