Coupling surge early warning and partition suppression method and system for double-head magnetic suspension air compressor

Abstract

The application discloses a double-head magnetic suspension air compressor coupling surge early warning and partition suppression method and system, the application collects the pressure signals of the exhaust ends of two parallel air compressors, and obtains actual pressure pulsation after denoising; correlation coupling is carried out based on the pressure pulsation of the two units, and an airflow coupling coefficient for quantifying the airflow coupling strength of the double-head is constructed; according to the coefficient and the allowed pressure pulsation amplitude, the operation interval is divided into a stable zone, a low-frequency disturbance zone and a malignant surge zone; and differentiated suppression strategies are executed for different zones, including flexible decoupling by speed difference and loading rate damping correction in the disturbance zone, and three-level protection in the malignant zone; the application can identify the hidden surge precursor that the system coupling is unstable although the single-machine parameters are normal, is suitable for all working conditions, and realizes precise early warning and partition suppression of surge.

Description

Technical Field

[0001] This invention relates to the field of surge control technology for magnetic levitation centrifugal air compressors, specifically to a method and system for coupled surge warning and zoned suppression of dual-head magnetic levitation air compressors. Background Technology

[0002] Current mainstream surge control solutions all use "independent pressure and flow thresholds for each compressor to determine surge," which can only protect the operating conditions of a single unit. However, dual-compressor parallel air compressors share the same intake manifold, exhaust manifold, and pressure stabilizing pipeline. The airflow pulsations generated by the high-speed operation of the two high-speed rotors will be mutually transmitted, superimposed, and coupled. In actual operation, it often happens that: the operating parameters of a single compressor head are completely normal and there are no surge characteristics, but the airflow of the two compressor heads interferes with each other, causing low-frequency pressure oscillations in the system, which ultimately induces surge in the whole machine. Traditional single-unit monitoring solutions cannot identify this type of coupled fault at all.

[0003] Meanwhile, the industry generally uses fixed pressure fluctuation rate and fixed pressure ratio threshold as surge judgment conditions. Magnetic levitation air compressors have a large speed range and a wide dynamic load adjustment range, with weak coupling disturbances under low loads and extremely strong coupling disturbances under high loads. Fixed thresholds cannot adapt to all operating conditions: if the threshold is too sensitive, it will lead to frequent unloading and de-loading during normal variable load operation, reducing the stability and energy efficiency of the system air supply; if the threshold is too insensitive, it will not be able to identify coupled oscillations in advance. By the time a single machine shows surge characteristics, the magnetic bearing rotor has already experienced significant eccentricity and excessive vibration, causing equipment damage, and failing to achieve surge warning and suppression for magnetic levitation air compressors. Summary of the Invention

[0004] Technical Objective: To address the shortcomings of existing surge control methods for magnetic levitation air compressors, this invention discloses a method and system for coupled surge warning and zoned suppression of dual-head magnetic levitation air compressors, which can quantify the disturbance coupling degree between compressor heads and effectively control surge.

[0005] Technical solution: To achieve the above technical objectives, the present invention adopts the following technical solution: This invention discloses a method for coupled surge warning and zone suppression of a dual-head magnetic levitation air compressor, comprising the following steps: S01. Collect the exhaust pressure signals of the two parallel magnetic levitation air compressors at the exhaust end respectively, and obtain the actual pressure pulsation of the corresponding magnetic levitation air compressor after denoising the exhaust pressure signals. Subtract the actual pressure pulsation from the exhaust pressure signal to obtain the pressure pulsation offset of each magnetic levitation air compressor. S02. Based on the actual pressure pulsation of the two magnetic levitation air compressors, correlation coupling is performed to construct the airflow coupling coefficient; S03. The operating range of the dual-head parallel magnetic levitation air compressor is divided according to the set coupling coefficient threshold and the pressure pulsation amplitude of the unit composed of two magnetic levitation air compressors connected in parallel. The pressure pulsation amplitude is the sum of the pressure pulsation offsets of the two magnetic levitation air compressors. The operating range includes the stable operating range, the low-frequency coupling disturbance range, and the malignant coupling surge range. S04. In different operating ranges, control the dual-head parallel magnetic levitation air compressor to execute the corresponding surge suppression strategy.

[0006] Preferably, in step S04 of the present invention, within the low-frequency coupling disturbance region, a small speed difference Δn is first set between the two magnetic levitation air compressors, the range of Δn being (0.2%-0.5%)×n, where n is the current speed of the magnetic levitation air compressor. This speed difference breaks the resonance condition of the airflow pulsation between the two compressors. Then, by adjusting the loading rate damping correction in conjunction with the decoupling of the small speed difference between the two compressors, the airflow coupling synchronization is broken. The corrected loading rate... ,in As the baseline loading rate, This is the loading rate after real-time correction; This represents the airflow coupling coefficient between the two magnetic levitation air compressors at the current moment.

[0007] Preferably, in step S04 of the present invention, surge suppression is performed through a three-level protection logic within the malignant coupling surge region; Level 1: Simultaneously limit and reduce the load on both magnetic levitation air compressors, reduce the output load, limit the increase in pressure ratio, and open the vent valve to leave the surge condition range; Level 2: Eliminate the load deviation and speed deviation accumulated during the operation of the two magnetic levitation air compressors, and restore the operating conditions of the two magnetic levitation air compressors to be consistent; Level 3: Coupling coefficient of the airflow to be processed After the pressure drops back to the stable operating range and the actual pressure pulsation recovers to below the allowable pressure pulsation amplitude, the load is gradually restored using a loading rate damping correction method based on the airflow coupling coefficient. The loading rate is calculated according to the formula... Adjustments will be made gradually, including As the baseline loading rate, This is the loading rate after real-time correction; is the airflow coupling coefficient of the two magnetic levitation air compressors at the current moment.

[0008] Preferably, in step S03 of the present invention, the coupling coefficient threshold includes two levels of thresholds. , , < The allowable pressure pulsation amplitude is calibrated and set according to the unit model and operating conditions. Calibration is performed based on the rated operating conditions of the unit; < And |ΔP| < It is currently in a stable operating range; ≤ < And |ΔP| < In the low-frequency coupling disturbance region, ≥ And |ΔP|≥ In the malignant coupling surge region, ΔP is the amplitude of pressure pulsation.

[0009] Preferably, the threshold of the present invention The value is dynamically adjusted based on the unit's real-time load rate, and the adjusted actual threshold is... ,in, The threshold value is set as the baseline surge coupling threshold, β is the load correction factor, and L is the real-time load rate of the unit; the threshold value is used to determine the surge coupling threshold. Dynamic correction is used to automatically lower the threshold under high load conditions to trigger protection in advance, and relax the threshold under low load conditions to avoid false protection.

[0010] Preferably, in step S01, when the actual pressure pulsation of the two magnetic levitation air compressors is obtained, the original exhaust pressure signal is collected in real time by a high-frequency pressure sensor preset at the exhaust end of the magnetic levitation air compressor. , t represents the signal acquisition time. A sliding window mean filter is used to remove equipment vibration and circuit interference noise, extracting the effective pressure pulsation component. The sliding window length is defined as N. The real-time pressure value after filtering is: This refers to the actual pressure pulsation of the two magnetic levitation air compressors. Based on the actual pressure pulsation, the pressure pulsation offset of the two magnetic levitation air compressors is calculated. .

[0011] Preferably, the airflow coupling coefficient of the present invention ,in, , representing the covariance of the pressure pulsation offset between the two magnetic levitation air compressors; , This represents the standard deviation of pulsation for the corresponding magnetic levitation air compressor. , .

[0012] This invention also discloses a surge warning and zone suppression system for a dual-head magnetic levitation air compressor. Using the above method, the system includes: The signal acquisition and processing module is configured to acquire the exhaust pressure signals from the exhaust ends of two parallel magnetic levitation air compressors respectively, and to perform noise reduction processing on the exhaust pressure signals to obtain the actual pressure pulsation of the corresponding magnetic levitation air compressor. The coupling analysis module is configured to perform correlation coupling based on the actual pressure pulsations of the two magnetic levitation air compressors, construct the airflow coupling coefficient, and analyze the coupling situation of the two magnetic levitation air compressors. The early warning and control module is configured to identify the operating range of the two magnetic levitation air compressors and control the magnetic levitation air compressors to execute the corresponding surge suppression strategy.

[0013] Beneficial Effects: The dual-head magnetic levitation air compressor coupled surge warning and zone suppression method and system disclosed in this invention have the following beneficial effects: 1. This invention establishes a dual-head parallel airflow coupling dynamic model, which can accurately quantify the airflow coupling intensity of the two magnetic levitation air compressors. It can identify in advance the hidden surge precursors of normal single-machine parameters and system coupling instability, and provide timely warning and suppression, thereby ensuring the stable operation of the unit.

[0014] 2. The coupling coefficient threshold set by this invention for dividing the unit operating range adopts a dynamic correction method based on the unit operating conditions. The surge judgment boundary is dynamically corrected according to the real-time dual-machine coupling coefficient to adapt to full load and full speed conditions. This enables the threshold to be automatically reduced under high load conditions to trigger protection in advance, and the threshold to be relaxed under low load conditions to avoid false protection.

[0015] 3. This invention divides the unit operation into three operating intervals by using a coupling coefficient threshold, and sets corresponding control strategies for each operating interval. It can match different decoupling, vibration suppression, and protection logic for different fault levels, avoiding over-protection and protection lag.

[0016] 4. This invention employs flexible decoupling adjustment in the low-frequency coupling disturbance zone. By setting a small speed difference between the two magnetic levitation air compressors, the resonance condition of the airflow pulsation between the two machines is broken, and the loading rate is damped and corrected. Surge suppression is achieved without affecting the unit's air supply pressure and flow rate. Compared with the traditional load reduction and shutdown protection methods, this invention can maintain the stable operation of the magnetic levitation air compressor in this operating range.

[0017] 5. The unique loading rate correction method of this invention can adaptively adjust the loading process according to the operating conditions of the unit, suppress the superposition of airflow pulsations, and thus reduce the risk of surge in the unit. Detailed Implementation

[0018] Reference will now be made in detail to embodiments of the present disclosure, one or more of which are set forth herein. Each embodiment and example is provided by way of explanation of the apparatus, composition, and materials of the present disclosure, and not by way of limitation. Rather, the following description provides convenient illustrations for implementing exemplary embodiments of the present disclosure. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made to the teachings of the present disclosure without departing from the scope or spirit of the present disclosure.

[0019] This invention discloses a method for coupled surge warning and zone suppression of a dual-head magnetic levitation air compressor, comprising the following steps: S01. Collect the exhaust pressure signals from the exhaust ends of the two parallel magnetic levitation air compressors respectively, and obtain the actual pressure pulsation of the corresponding magnetic levitation air compressor after noise reduction processing based on the exhaust pressure signals. In step S01, when the actual pressure pulsation of the two magnetic levitation air compressors is obtained, the invention uses a high-frequency pressure sensor pre-installed at the exhaust end of the magnetic levitation air compressor to collect the raw exhaust pressure signal in real time. , , This is the exhaust pressure of the first magnetic levitation air compressor. The discharge pressure of the second magnetic levitation air compressor is given by t, which represents the signal acquisition time. A sliding window mean filter is used to remove equipment vibration and circuit interference noise, extracting the effective pressure pulsation component. The sliding window length is defined as N. The filtered real-time pressure value is: This corresponds to the actual pressure pulsation of the magnetic levitation air compressor, and then the pressure pulsation offset is calculated. , This represents the pressure pulsation offset of the first magnetic levitation air compressor. This represents the pressure pulsation offset of the second magnetic levitation air compressor. The pressure pulsation offset can directly reflect the airflow stability of a single magnetic levitation air compressor.

[0020] The pressure pulsation amplitude ΔP of a unit consisting of two magnetic levitation air compressors connected in parallel is = .

[0021] S02. Based on the actual pressure pulsation of the two magnetic levitation air compressors, correlation coupling is performed to construct the airflow coupling coefficient; The core cause of surge in parallel operation of two air compressors is the correlation and coupling of pressure pulsations between the two magnetic levitation air compressors. While the pulsation of a single compressor may not be abnormal, when the pulsation trends of both compressors are superimposed synchronously, it can cause pipeline resonance and system instability. To address this, this invention analyzes the pressure pulsation of a single compressor head to construct a real-time airflow coupling coefficient and quantifies the correlation strength of disturbances between the two compressor heads, so as to provide surge warning and control and ensure the safe operation of the unit.

[0022] The airflow coupling coefficient of the present invention ,in, , representing the covariance of the pressure pulsation offset between the two magnetic levitation air compressors, characterizing the degree of coupling between the two magnetic levitation air compressors. This is the arithmetic mean of the pressure pulsation deviation of the first magnetic levitation air compressor within the length of the sliding window. The arithmetic mean of the pressure pulsation deviation of the second magnetic levitation air compressor within the length of the sliding window; , This represents the standard deviation of the pulsation for the corresponding magnetic levitation air compressor, characterizing the intensity of pressure pulsation fluctuations. , .

[0023] at this time A value less than zero indicates that the coupling phases are opposite, so that the pressure pulsation does not exceed the limit and the protection is not triggered. The closer the value is to 1, the stronger the synchronization of the heating pressure pulsation of the two magnetic levitation air compressors and the more serious the airflow coupling, and the higher the risk of system resonance and coupling surge. The closer the absolute value is to 0, the more independent the disturbance of the two machines is, the no coupling interference, and the stable operation of the system.

[0024] S03. The operating range of the dual-head parallel magnetic levitation air compressor is divided according to the set coupling coefficient threshold and the pressure pulsation amplitude of the unit composed of two magnetic levitation air compressors connected in parallel. The pressure pulsation amplitude is the sum of the pressure pulsation offsets of the two magnetic levitation air compressors. The operating range includes the stable operating range, the low-frequency coupling disturbance range, and the malignant coupling surge range. This invention sets a coupling coefficient threshold and divides the operating range based on the pressure pulsation amplitude of a unit composed of two magnetically levitated air compressors. The coupling coefficient threshold includes two levels of thresholds. , , < The calibration and settings are performed according to the unit's model and operating conditions.

[0025] Specifically: Threshold It is the critical point between no obvious system disturbance and perceptible coupled oscillation. The calibration goal is to identify the implicit coupling trend in advance without affecting the stability of the air supply: two magnetic levitation air compressors are running synchronously, and the total load is gradually increased from 30% to 100%, with each 5% load as a test point; the system runs stably for 5 minutes at each load point, and the pressure pulsation signals of the two magnetic levitation compressors are collected in real time and the airflow coupling coefficient is calculated.

[0026] When any of the following phenomena are observed, record the airflow coupling coefficient at that moment as a threshold. Initial value: 1. The exhaust manifold pressure exhibits low-frequency fluctuations with a period of 1~5Hz; a pressure transmitter with a sampling accuracy greater than 1kHz can be selected, and the data can be connected to an oscilloscope for fluctuation detection. 2. The radial vibration amplitude of the magnetic bearing increases by ≥20% compared to stable operation; 3. The motor currents of the two magnetic levitation air compressors exhibit synchronous small fluctuations (fluctuation amplitude ≥ 3%). Threshold for all load points The initial value is taken as the arithmetic mean, and then multiplied by a safety factor of 0.8 to 0.9 to obtain the threshold. The baseline value.

[0027] threshold It is the critical point that can suppress coupled disturbances and irreversible coupled surge. Calibration must be carried out under the condition that the test bench safety protection measures are complete: two magnetic levitation air compressors are running synchronously, and the total load is kept stable at 100% of the rated load; by manually adjusting the load and the speed difference between the two machines, for example, by reducing the opening of the valve at the end of the pipeline of one of the magnetic levitation air compressors, the surge margin of a single machine is reduced. Then, the speed difference between the two compressors is further reduced, and it can be seen that the coupling degree between the two machines increases until surge occurs. At this time, the surge flow rate is greater than the surge flow rate when a single machine is working alone, thereby forcibly increasing the airflow coupling strength between the two machines.

[0028] Real-time monitoring of airflow coupling coefficient, pressure pulsation amplitude, and magnetic bearing vibration; when any of the following surge precursors appear, the airflow coupling coefficient at that moment is immediately recorded as a threshold. Initial value: 1. The pressure pulsation amplitude ΔP of the unit reaches or exceeds ; 2. The vibration amplitude of the magnetic bearing exceeds 0.7µm; 3. The speeds of both machines exhibit synchronous oscillation (oscillation frequency 0.5~2Hz); Record threshold The initial value is taken as the arithmetic mean, multiplied by a safety factor of 0.7 to 0.8 to obtain the threshold. Benchmark value.

[0029] Permissible pressure pulsation amplitude The unit is calibrated according to its rated operating conditions. The magnetic levitation air compressor is operated to reach its nameplate flow rate and pressure. The pressure pulsation amplitude of the unit under the current operating conditions is recorded and then multiplied by a coefficient of 1.2 to obtain the maximum allowable pressure pulsation amplitude.

[0030] < And |ΔP| < It is currently in a stable operating range; ≤ < And |ΔP| < In the low-frequency coupling disturbance region, ≥ And |ΔP|≥ In the malignant coupling surge region, ΔP is the amplitude of pressure pulsation.

[0031] S04. In different operating ranges, control the dual-head parallel magnetic levitation air compressor to execute the corresponding surge suppression strategy.

[0032] Within the stable operating range, the original load distribution and speed regulation logic are maintained without interfering with the operation of the magnetic levitation air compressor. The two magnetic levitation air compressors are loaded synchronously at the reference rate, maintaining the rated synchronous speed without speed difference. The output power is increased synchronously according to the preset load balancing strategy, keeping the load deviation between the two magnetic levitation air compressors ≤2%. The airflow coupling coefficient and pressure pulsation amplitude are tracked in real time. If the airflow coupling coefficient exceeds the threshold, the control strategy for the low-frequency coupling disturbance zone is immediately switched.

[0033] Within the low-frequency coupled disturbance region, there are no single-machine surge characteristics, but the airflow of the two machines shows a clear tendency for coupled resonance, which is a sub-healthy and unstable state.

[0034] First, set a small speed difference Δn between the two magnetic levitation air compressors. The range of Δn is (0.2%-0.5%)×n, where n is the current speed of the magnetic levitation air compressor. The speed difference breaks the resonance condition of the airflow pulsation between the two machines. For example, one magnetic levitation air compressor maintains its current speed, while the other magnetic levitation air compressor increases its speed by 80 rpm.

[0035] Then, by adjusting the loading rate damping correction and decoupling the two-machine speed differential, the airflow coupling synchronization is broken; the corrected loading rate ,in As the baseline loading rate, This is the loading rate after real-time correction; This represents the airflow coupling coefficient between the two magnetic levitation air compressors at the current moment. The loading rate is the rate at which the load of the magnetic levitation air compressor increases per unit time; in practical applications, it is the rate of increase in motor speed. For example, if the rated motor speed is 30,000 RPM and the loading rate is 1%, then the rate of increase / decrease in motor speed is 300 RPM / s. Both magnetic levitation air compressors adjust their loading rates according to load requirements, gradually completing the loading operation. The stronger the coupling, the more significant the change in loading rate adjustment. For example, when the airflow coupling coefficient is 0.5, the adjusted loading rate drops to 50% of the baseline loading rate.

[0036] Surge suppression is achieved through a three-level protection logic within the malignant coupling surge region. Level 1: Simultaneously limit and reduce the load on both magnetic levitation air compressors, reduce the output load, limit the increase in pressure ratio, and open the vent valve to leave the surge condition range; Unloading is performed at the maximum deceleration rate specified by the manufacturer, reducing output power while opening the vent valve. Both magnetic levitation air compressors maintain the same deceleration rate to prevent increased airflow coupling.

[0037] Level 2: Eliminate the load and speed deviations accumulated during the operation of the two magnetic levitation air compressors, and restore the operating conditions of the two magnetic levitation air compressors to be consistent.

[0038] The speed deviation and load deviation caused by the slight speed difference adjustment in the low-frequency coupling disturbance zone of the two magnetic levitation air compressors are reset, and the state of the two magnetic levitation air compressors is restored to the same before they are reloaded and put into the pipeline network for operation.

[0039] Level 3: After the airflow coupling coefficient returns to the stable operating range and the actual pressure pulsation recovers to below the allowable pressure pulsation amplitude, the two magnetic levitation air compressors are synchronously loaded using a loading rate damping correction method based on the airflow coupling coefficient, gradually restoring the load. The loading rate is determined according to the formula... Adjustments will be made gradually, where R0 is the baseline loading rate. This is the loading rate after real-time correction; This represents the airflow coupling coefficient between the two magnetic levitation air compressors at the current moment.

[0040] To address the limitation of fixed thresholds in adapting to varying operating conditions, this invention employs a method of dynamically adjusting the coupling judgment threshold based on the unit load rate. This primarily targets operating conditions in the severe coupling surge zone. The size is dynamically adjusted based on the unit's real-time load rate. ,in, The threshold value is set as the baseline surge coupling threshold, β is the load correction factor, and L is the real-time load rate of the unit; the threshold value is used to determine the surge coupling threshold. Dynamic correction is implemented to automatically lower the threshold and trigger protection in advance under high load conditions, and relax the threshold under low load conditions to avoid false protection. The calibration steps for the load correction coefficient β are as follows: gradually increase the total load rate of the unit from 30% to 100%, with each 10% load as a test point. At each load point, the operation is adjusted to the critical coupling state, and the actual coupling threshold at this time is recorded. , The calculated β is averaged and multiplied by a safety factor of 0.9 to obtain the factory calibration value. In this embodiment of the invention, the load correction factor β is 0.2-0.4.

[0041] This invention also discloses a surge warning and zone suppression system for a dual-head magnetic levitation air compressor. Using the above method, the system includes: The signal acquisition and processing module is configured to acquire the exhaust pressure signals from the exhaust ends of two parallel magnetic levitation air compressors respectively, and to perform noise reduction processing on the exhaust pressure signals to obtain the actual pressure pulsation of the corresponding magnetic levitation air compressor. The coupling analysis module is configured to perform correlation coupling based on the actual pressure pulsations of the two magnetic levitation air compressors, construct the airflow coupling coefficient, and analyze the coupling situation of the two magnetic levitation air compressors. The early warning and control module is configured to identify the operating range of the two magnetic levitation air compressors and control the magnetic levitation air compressors to execute the corresponding surge suppression strategy.

[0042] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for coupled surge warning and zoned suppression of a dual-head magnetic levitation air compressor, characterized in that, Including the following steps: S01. Collect the exhaust pressure signals of the two parallel magnetic levitation air compressors at the exhaust end respectively, and obtain the actual pressure pulsation of the corresponding magnetic levitation air compressor after denoising the exhaust pressure signals. Subtract the actual pressure pulsation from the exhaust pressure signal to obtain the pressure pulsation offset of each magnetic levitation air compressor. In step S01, when the actual pressure pulsation of the two magnetic levitation air compressors is obtained, the raw exhaust pressure signal is collected in real time by a high-frequency pressure sensor preset at the exhaust end of the magnetic levitation air compressor. , t represents the signal acquisition time. A sliding window mean filter is used to remove equipment vibration and circuit interference noise, extracting the effective pressure pulsation component. The sliding window length is defined as N. The real-time pressure value after filtering is: This refers to the actual pressure pulsation of the two magnetic levitation air compressors. Based on the actual pressure pulsation, the pressure pulsation offset of the two magnetic levitation air compressors is calculated. ; S02. Based on the actual pressure pulsation of the two magnetic levitation air compressors, correlation coupling is performed to construct the airflow coupling coefficient; S03. The operating range of the dual-head parallel magnetic levitation air compressor is divided according to the set coupling coefficient threshold and the pressure pulsation amplitude of the unit composed of two magnetic levitation air compressors connected in parallel. The pressure pulsation amplitude is the sum of the pressure pulsation offsets of the two magnetic levitation air compressors. The operating range includes the stable operating range, the low-frequency coupling disturbance range, and the malignant coupling surge range. In step S03, the coupling coefficient threshold includes two levels of thresholds. , , < The allowable pressure pulsation amplitude is calibrated and set according to the unit model and operating conditions. Calibration is performed based on the rated operating conditions of the unit; < And |ΔP| < It is currently in a stable operating range; ≤ < And |ΔP| < In the low-frequency coupling disturbance region, ≥ And |ΔP|≥ In the malignant coupling surge region, ΔP is the amplitude of pressure pulsation; S04. In different operating ranges, control the dual-head parallel magnetic levitation air compressor to execute the corresponding surge suppression strategy; In step S04, within the low-frequency coupling disturbance region, a small speed difference Δn is first set between the two magnetic levitation air compressors. Δn ranges from (0.2% to 0.5%) × n, where n is the current speed of the magnetic levitation air compressor. This speed difference breaks the resonance condition of the airflow pulsation between the two compressors. Then, by adjusting the loading rate damping correction in conjunction with the decoupling of the small speed difference between the two compressors, the airflow coupling synchronization is broken. The corrected loading rate... ,in As the baseline loading rate, This is the loading rate after real-time correction; This represents the airflow coupling coefficient between the two magnetic levitation air compressors at the current moment.

2. The method for coupled surge warning and zoned suppression of a dual-head magnetic levitation air compressor according to claim 1, characterized in that, In step S04, surge suppression is performed through a three-level protection logic within the malignant coupling surge zone. Level 1: Simultaneously limit and reduce the load on both magnetic levitation air compressors, reduce the output load, limit the increase in pressure ratio, and open the vent valve to leave the surge condition range; Level 2: Eliminate the load deviation and speed deviation accumulated during the operation of the two magnetic levitation air compressors, and restore the operating conditions of the two magnetic levitation air compressors to be consistent; Level 3: Coupling coefficient of the airflow to be processed After the pressure drops back to the stable operating range and the actual pressure pulsation recovers to below the allowable pressure pulsation amplitude, the load is gradually restored using a loading rate damping correction method based on the airflow coupling coefficient. The loading rate is calculated according to the formula... Adjustments will be made gradually, including As the baseline loading rate, This is the loading rate after real-time correction; is the airflow coupling coefficient of the two magnetic levitation air compressors at the current moment.

3. The method for coupled surge warning and zoned suppression of a dual-head magnetic levitation air compressor according to claim 1, characterized in that, threshold The value is dynamically adjusted based on the unit's real-time load rate, and the adjusted actual threshold is... ,in, The threshold value is set as the baseline surge coupling threshold, β is the load correction factor, and L is the real-time load rate of the unit; the threshold value is used to determine the surge coupling threshold. Dynamic correction is used to automatically lower the threshold under high load conditions to trigger protection in advance, and relax the threshold under low load conditions to avoid false protection.

4. The method for coupled surge warning and zoned suppression of a dual-head magnetic levitation air compressor according to claim 1, characterized in that, airflow coupling coefficient ,in, , representing the covariance of the pressure pulsation offset between the two magnetic levitation air compressors; , This represents the standard deviation of pulsation for the corresponding magnetic levitation air compressor. , .

5. A surge warning and zone suppression system for a dual-head magnetic levitation air compressor, using the method described in any one of claims 1-4, characterized in that, include: The signal acquisition and processing module is configured to acquire the exhaust pressure signals from the exhaust ends of two parallel magnetic levitation air compressors respectively, and to perform noise reduction processing on the exhaust pressure signals to obtain the actual pressure pulsation of the corresponding magnetic levitation air compressor. The coupling analysis module is configured to perform correlation coupling based on the actual pressure pulsations of the two magnetic levitation air compressors, construct the airflow coupling coefficient, and analyze the coupling situation of the two magnetic levitation air compressors. The early warning and control module is configured to identify the operating range of the two magnetic levitation air compressors and control the magnetic levitation air compressors to execute the corresponding surge suppression strategy.

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