Magnetic suspension molecular pump operation analysis system and method based on digital twinning

Abstract

The invention provides a magnetic suspension molecular pump operation analysis system and method based on digital twinning. The magnetic suspension molecular pump operation analysis system comprises a molecular pump physical system, a digital twinning model mapping system and a digital twinning information processing system. The molecular pump physical system comprises a magnetic suspension molecular pump and various arranged sensors; the digital twin model mapping system comprises an established magnetic suspension molecular pump three-dimensional model and a human-computer interaction interface, and presents real-time molecular pump state change; the digital twinborn information processing system comprises a data storage module, a control module and a data processing module, and the data processing module calculates the obtained real-time parameters, generates a state result and updates the three-dimensional model. The digital twinborn technology is applied to the field of the magnetic suspension molecular pump through ingenious design, the running state parameters of the molecular pump are obtained in real time and visually presented through reasonable arrangement of various sensors, and a technician can conduct accurate monitoring, analysis and the like according to obtained real-time data and periodic data.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic levitation molecular pump operation monitoring, and in particular relates to a magnetic levitation molecular pump operation analysis system and method based on digital twin. Background Art

[0002] The magnetic levitation molecular pump is a molecular pump technology that uses the frictionless magnetic levitation principle to achieve long-term safe, reliable, energy-saving and stable flow control. Because the magnetic levitation molecular pump adopts frictionless magnetic levitation technology, it reduces vibration and noise compared to traditional mechanical bearing turbomolecular pumps, and can work stably for a long time and achieve more precise control and regulation. In view of the excellent performance of the magnetic levitation molecular pump, the magnetic levitation molecular pump is widely used in the semiconductor industry and other fields, such as gas extraction in etching, ion implantation and photolithography to obtain a vacuum environment.

[0003] The existing monitoring of magnetic levitation molecular pumps is often to monitor a single state, and cannot be displayed intuitively. The technicians cannot obtain the operating status of each part of the molecular pump in real time, so as to make an accurate judgment on the operating failure; at the same time, the technicians cannot analyze the overall periodic operation process of the magnetic levitation molecular pump, so as to conduct early fault warning analysis or life analysis. The existing magnetic levitation molecular pump control technology is not yet mature in China, and there is currently a lack of an overall operating status intuitive display system to further assist research and development. Summary of the invention

[0004] In order to solve the problems in the background technology, the present invention is based on the concept of digital twins. In the first aspect, a magnetic levitation molecular pump operation analysis system based on digital twins is proposed, including a molecular pump physical system, a digital twin model mapping system and a digital twin information processing system; the molecular pump physical system includes a magnetic levitation molecular pump and a temperature sensor, a current sensor, a displacement sensor, a molecular pump speed sensor, a vibration sensor and a vacuum gauge, and the temperature sensor, the current sensor and the displacement sensor are integrated on the axial magnetic bearing and the radial magnetic bearing; the digital twin model mapping system includes a three-dimensional model of a magnetic levitation molecular pump established by three-dimensional modeling software and a human-computer interaction interface, which is used to present real-time molecular pump state changes; the digital twin information processing system includes a data storage module, a control module and a data processing module, the data storage module is used to store the original parameters and real-time change parameters of the molecular pump, the control module obtains real-time sensor data through the molecular pump controller and sends it to the data processing module, the data processing module calculates the acquired real-time parameters and generates a state result, and the control module updates and presents the three-dimensional model of the magnetic levitation molecular pump in real time according to the generated state result.

[0005] Preferably, the three-dimensional model of the magnetic levitation molecular pump established by the three-dimensional modeling software is to model the magnetic levitation molecular pump by solidworks software; wherein the rotor blade disk rotates at high speed, the root of the blade will be affected by a strong centrifugal force, and the centrifugal force on the blade row increases successively from the inner ring to the outer ring. In order to monitor whether the blade will be damaged during operation, the blade row structure is simulated and analyzed; the three-dimensional model of the rotor disk is drawn by SolidWorks software and saved in x_t format, and the Static Structural module in ANSYS WorkBench software is used to import the rotor three-dimensional model, set the rotor material properties and rated speed, and select the bearing support point at the design position, simulate and analyze the stress, strain and displacement of the blade, and it can be presented in the digital twin model mapping system.

[0006] Preferably, an early warning module is integrated in the digital twin model mapping system, and the temperature setting range is 5°C to 35°C. When the temperature obtained by the temperature sensor exceeds 35°C, an early warning is issued.

[0007] Preferably, 9 groups of displacement sensors are provided; the magnetic levitation molecular pump includes a first radial magnetic bearing, a second radial magnetic bearing and an axial magnetic bearing, the first radial magnetic bearing constructs the XY axis coordinates of a two-dimensional plane, wherein 4 groups of displacement sensors are relatively arranged on the XY axis coordinates; the second radial magnetic bearing constructs the AB axis coordinates of a two-dimensional plane, wherein 4 groups of displacement sensors are relatively arranged on the AB axis coordinates; the axial magnetic bearing is the Z axis along the axial direction, and a group of displacement sensors is arranged below it; the 9 groups of displacement sensors acquire the five-axis coordinate positions in real time and send them to the data processing module, the data processing module calculates the acquired real-time data and generates status results, presents them on the three-dimensional model of the magnetic levitation molecular pump, and records abnormal results in the data storage module for later maintenance.

[0008] Preferably, the current sensor is used to obtain the real-time current of the coils of the radial magnetic bearing and the axial magnetic bearing, and compare it with the factory-preset rotor suspension control current stored in the storage module. When an abnormality occurs, an early warning is issued through the early warning module of the twin model mapping system.

[0009] Preferably, the vacuum gauge is used to obtain the vacuum degree when the magnetic levitation molecular pump is running, and the data processing module can generate a change curve graph of the change in vacuum degree, which can be recorded in the data storage module and presented through a human-computer interaction interface.

[0010] Preferably, the data storage module stores a disturbance separation extended state observer model, based on which the displacement, imbalance and other disturbance parameters of each channel are obtained and presented in the digital twin model mapping system; the construction method of the disturbance separation extended state observer model is:

[0011] Acquire a rotor dynamics model at the center of mass position; acquire an unbalanced vibration model at the magnetic bearing position based on the rotor dynamics model; acquire rotor position information in real time and convert it into a displacement measurement signal at the magnetic bearing position; establish a system model based on the unbalanced vibration model and the displacement measurement signal; and establish a disturbance separation extended state observer assisted by system model information based on the system model.

[0012] Preferably, the molecular pump speed sensor is used to obtain the real-time speed of the rotor when the magnetic levitation molecular pump is running, and the data processing module can generate a change curve graph of the speed change, which can be recorded in the data storage module and presented through the human-computer interaction interface.

[0013] Preferably, the vibration sensor is fixed to the outside of the molecular pump housing through a magnetic base, and is used to obtain the transient value of the rotor vibration amplitude, and generate a floating waveform diagram of the magnetically suspended rotor in a certain degree of freedom direction by a waveform analysis method through a data processing module, which can be recorded in the data storage module and presented through a human-computer interaction interface, and the user can judge the abnormal situation of the rotor through the waveform diagram;

[0014] For simple harmonic oscillation, the mathematical equation for the waveform is:

[0015] x(t)=A sin(wt+φ)=A sin(2πft+φ)

[0016] In the formula, A is the vibration peak value, also known as the single amplitude, which reflects the magnitude of the vibration; w is the angular frequency, which indicates the speed of the vibration. The larger the unit rad / sw, the faster the vibration; f is the frequency, in Hertz, f = w / 2π; the reciprocal of f is called the period T, in seconds S; φ is the initial phase angle, φ reflects the starting position of the waveform, φ ＞0 When φ ＜0 It is called phase lag; x(t) is the instantaneous amplitude of the vibration, and its unit is the same as A; taking a certain point on the rotor as the phase reference point, we can know the relative position relationship between the instantaneous values ​​on the vibration waveform and each point on the rotor, and the peak-to-peak value can be used to indicate the maximum amplitude of the vibration; the rotor vibration waveform is composed of many simple harmonic vibration components; the synthesis of two simple harmonic waves with the same frequency is still a simple harmonic waveform with the same frequency, but the amplitude and phase change.

[0017] The second aspect of the present invention provides a method for analyzing the operation of a magnetic levitation molecular pump based on digital twins, and includes the following process:

[0018] A three-dimensional model of a magnetic levitation molecular pump is established through modeling software, and a digital twin model mapping system is constructed; a molecular pump physical system is constructed, including a magnetic levitation molecular pump and a temperature sensor, a current sensor, a displacement sensor, a molecular pump speed sensor, a vibration sensor and a vacuum gauge, wherein the temperature sensor, the current sensor and the displacement sensor are integrated on the axial magnetic bearing and the radial magnetic bearing; a digital twin information processing system is constructed, including a data storage module, a control module and a data processing module; the data storage module is used to store the original parameters of the molecular pump and the real-time changing parameters;

[0019] During operation, the data of each sensor is obtained through the molecular pump controller and sent to the data processing module through the communication module. The data processing module calculates the acquired real-time parameters and generates status results. The control module updates and presents the three-dimensional model of the magnetic levitation molecular pump in real time according to the generated status results. When data abnormalities occur, an early warning is issued.

[0020] The present invention discloses a magnetic levitation molecular pump operation analysis system and method based on digital twin, which has the following beneficial effects compared with the prior art:

[0021] The present invention applies the digital twin technology to the field of suspended molecular pump operation monitoring through ingenious design. Through the reasonable setting of various sensors (such as the reasonable setting of 9 groups of displacement sensors), the operating status parameters of the molecular pump are obtained in real time, and intuitively presented through the digital twin model mapping system. Technicians can obtain the operating status of each part of the molecular pump in real time, so as to make accurate judgments on operating failures; at the same time, the entire digital twin analysis system can record and generate some data graphs. For example, the vibration waveform analysis graph designed by the vibration sensor of the present invention is simple and intuitive. Technicians can analyze the overall periodic operation process of the magnetic levitation molecular pump, and perform fault warning analysis or life analysis in advance; the control technology of the magnetic levitation molecular pump is not yet mature in China. The intuitive display and data recording of its overall operating status can help technicians further obtain research and development inspiration and research and development direction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, what is described below is only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0023] Figure 1It is the overall structural block diagram of the magnetic suspension molecular pump operation analysis system of the present invention;

[0024] Figure 2 Schematic diagram of the arrangement of 9 groups of displacement sensors in the embodiment;

[0025] Figure 3 This is a diagram showing the stress analysis of the rotor blades;

[0026] Figure 4 It is a flowchart of the construction method of the disturbance separation extended state observer model. DETAILED DESCRIPTION

[0027] The technical solutions in the specific embodiments of the present invention are clearly and completely described below in conjunction with the accompanying drawings in the present invention.

[0028] Digital twin is an emerging technology with real-time synchronization and high-fidelity characteristics. Through the information interaction and fusion between high-fidelity model simulation data and measured data, the virtual model is continuously updated, making the virtual model an accurate implementation mapping of the physical entity.

[0029] Based on the concept of digital twin, the present invention provides a magnetic levitation molecular pump operation analysis system based on digital twin, the overall structure of which is as follows: Figure 1As shown, it includes a molecular pump physical system, a digital twin model mapping system and a digital twin information processing system; the molecular pump physical system is equivalent to the physical space, and the actual magnetic levitation molecular pump system structure includes a magnetic levitation molecular pump and a temperature sensor, a current sensor, a displacement sensor, a molecular pump speed sensor, a vibration sensor and a vacuum gauge. The temperature sensor, the current sensor and the displacement sensor are integrated on the axial magnetic bearing and the radial magnetic bearing. The temperature sensor is used to obtain the real-time temperature of the radial magnetic bearing. The heat source generated when the molecular pump is running mainly comes from the magnetic bearing stator of the molecular pump. The digital twin model mapping system is integrated with an early warning module. The temperature setting range is 5°C to 35°C. When the temperature obtained by the temperature sensor exceeds 35°C, an early warning is issued; the current sensor is used to obtain the real-time current of the coils of the radial magnetic bearing and the axial magnetic bearing, and compare it with the factory preset rotor suspension control current stored in the storage module. The coil current values ​​of the radial magnetic bearing and the axial magnetic bearing should be the set values ​​when the magnetic suspension molecular pump is factory-installed for rotor dynamic balance adjustment. When an abnormality occurs, an early warning is issued through the early warning module of the twin model mapping system; the vacuum gauge is used to obtain the vacuum degree when the magnetic suspension molecular pump is running. The data processing module can generate a change curve graph for the change of the vacuum degree. It can be recorded in the data storage module and presented through the human-computer interaction interface, which is convenient for technicians to judge the performance changes of the molecular pump; the molecular pump speed sensor is used to obtain the real-time speed of the rotor when the magnetic suspension molecular pump is running. The data processing module can generate a change curve graph for the change of the speed. It can be recorded in the data storage module and presented through the human-computer interaction interface.

[0030] Regarding the setting method of displacement sensor, such as Figure 2 As shown: the magnetic levitation molecular pump includes a rotor 1, and a top bearing 2 and a bottom bearing 7 for protecting and limiting the rotor when in use; the magnetic levitation molecular pump includes a first radial magnetic bearing 4, a second radial magnetic bearing 8 and an axial magnetic bearing 6, and the first radial magnetic bearing 4 and the second radial magnetic bearing are arranged on the upper and lower sides of the motor stator 5; there are 9 groups of displacement sensors 3; the first radial magnetic bearing constructs the XY axis coordinates of the two-dimensional plane, wherein 4 groups of displacement sensors are arranged relatively on the XY axis coordinates; the second radial magnetic bearing constructs the AB axis coordinates of the two-dimensional plane, wherein 4 groups of displacement sensors are arranged relatively on the AB axis coordinates; the axial magnetic bearing is the Z axis along the axial direction, and a group of displacement sensors is arranged below it; the 9 groups of displacement sensors obtain the five-axis coordinate positions in real time and send them to the data processing module, the data processing module calculates the obtained real-time data and generates the status results, presents them on the three-dimensional model of the magnetic levitation molecular pump, and records the abnormal results in the data storage module for later maintenance.

[0031] Among them, the vibration sensor is fixed to the outside of the molecular pump housing through a magnetic base to obtain the transient value of the rotor vibration amplitude, and the data processing module uses the waveform analysis method to generate the floating waveform diagram of the magnetic suspension rotor in a certain degree of freedom direction. It can be recorded in the data storage module and presented through the human-computer interaction interface. The user can judge the abnormal situation of the rotor through the waveform diagram; the magnetic suspension rotor must monitor the running state of the rotor during high-speed rotation. If the rotor fails during high-speed rotation, certain measures must be taken to safely shut down the magnetic bearing. The vibration waveform is a dynamic image formed by the continuous change of the transient value of the rotor vibration amplitude over time. Waveform analysis is to establish a corresponding relationship between the shape, amplitude, speed of change and other characteristics of the waveform and the rotor state through analysis and observation to achieve the purpose of discovering rotor abnormalities and diagnosing rotor faults. The rotor will inevitably vibrate during operation. Generally speaking, the vibration is composed of a series of simple harmonic vibration components, other vibration components and random noise. Among them, the frequency of the simple harmonic vibration component is mostly related to the rotor speed or natural frequency. Irregular vibration mainly comes from nonlinear self-excited vibration. For simple harmonic vibration, the mathematical equation of the waveform is:

[0032] x(t)=A sin(wt+φ)=A sin(2πft+φ)

[0033] In the formula, A is the vibration peak value, also known as the single amplitude, which reflects the magnitude of the vibration; w is the angular frequency, which indicates the speed of the vibration. The larger the unit rad / sw, the faster the vibration; f is the frequency, in Hertz, f = w / 2π; the reciprocal of f is called the period T, in seconds S; φ is the initial phase angle, φ reflects the starting position of the waveform, φ ＞0 When φ ＜0 When the phase lag is called phase lag; x(t) is the instantaneous amplitude of the vibration, and the unit is the same as A; although the waveform of the actual vibration signal is much more complicated than the simple harmonic vibration, it can still be analyzed using the concepts in the simple harmonic vibration, and the frequency of each component is often compared with the rotor speed. Taking a certain point on the rotor as the phase reference point, the relative position relationship between each instantaneous value on the vibration waveform and each point on the rotor can be known, and the peak-to-peak value can be used to represent the maximum amplitude of the vibration; the rotor vibration waveform is synthesized by many simple harmonic vibration components, and the shape of the synthesized waveform is related to the frequency, amplitude and phase of the synthesized components; the synthesis of two simple harmonic waves with the same frequency is still a simple harmonic waveform of the same frequency, but the amplitude and phase change. The waveform of the superposition of two sinusoidal waveforms with different amplitudes and a frequency difference of one times is still a periodic waveform.

[0034] As a preferred solution, the system can also include an acceleration sensor, which is attached to the housing of the molecular pump; when the molecular pump is turned on, the vibration acceleration value of the molecular pump is measured by the acceleration sensor and sent to the spectrum analyzer, and then the spectrum analyzer is used to obtain the data of the acceleration value spectrum change in a certain frequency range; the data of the acceleration value spectrum change in a certain frequency range are used to judge the bearing operation state of the molecular pump; when it is in a high-frequency state, the acceleration signal value is small and there is no noise, indicating that the molecular pump is in a good operating state; when it is in a high-frequency state, the acceleration signal value is large and there is noise, indicating that the molecular pump is in a bad operating state; when it is in a high-frequency state, the acceleration signal value is large and dense and there are many noises, indicating that the pump state is very bad and needs maintenance. The data processing module can record the corresponding acceleration signal value in the data storage module and present it through the human-computer interaction interface.

[0035] The digital twin model mapping system is equivalent to a digital presentation platform, including a three-dimensional model of a magnetic levitation molecular pump established through three-dimensional modeling software and a human-computer interaction interface, which is used to present real-time changes in the state of the molecular pump; the digital twin information processing system includes a data storage module, a control module and a data processing module. The data storage module is used to store the original parameters and real-time changing parameters of the molecular pump. The control module obtains real-time sensor data through the molecular pump controller and sends it to the data processing module. The molecular pump controller is equivalent to a lower computer, which is used to control and obtain real-time data from various sensors and transmit it through the communication module. The data processing module calculates the acquired real-time parameters and generates status results. The control module updates and presents the three-dimensional model of the magnetic levitation molecular pump in real time according to the generated status results.

[0036] Among them, the three-dimensional model of the magnetic levitation molecular pump established by the three-dimensional modeling software is to model the magnetic levitation molecular pump by solidworks software; the rotor blade disk rotates at high speed, the root of the blade will be affected by a strong centrifugal force, and the centrifugal force of the blade row increases from the inner ring to the outer ring. In order to monitor whether the blade will be damaged during operation, the blade row structure is simulated and analyzed; the three-dimensional model of the rotor disk is drawn by SolidWorks software and saved in x_t format, and the Static Structural module in ANSYS WorkBench software is used to import the rotor three-dimensional model, set the rotor material properties and rated speed, and select the bearing support point at the design position. The blade parameters are shown in Table 1. The stress, strain and displacement of the blade are simulated and analyzed, and can be presented in the digital twin model mapping system, such as Figure 3 shown.

[0037] Table 1 Blade parameters

[0038]

[0039] The data storage module stores a disturbance separation extended state observer model. Based on the disturbance separation extended state observer, the displacement, imbalance and other disturbance parameters of each channel are obtained and presented in the digital twin model mapping system. The construction method of the disturbance separation extended state observer model is as follows: Figure 4 As shown:

[0040] First, obtain the rotor dynamics model at the center of mass; the model formula is as follows:

[0041]

[0042] Where m is the rotor mass, J z is the rotor pole moment of inertia, J x , J y are the equatorial moments of inertia of the rotor in the x and y directions, l am , l bm are the distances from the center of the magnetic bearings at ends A and B to the center of mass of the rotor; x I (α I ), y I (β I ) are the translational (rotational) displacements of the rotor mass center in the x and y directions in the geometric coordinate system; f ax 、f bx 、f ay 、f by is the electromagnetic force generated by the radial magnetic bearing in each direction; Ω is the angular velocity of the rotor.

[0043] Based on the rotor dynamics model, an unbalanced vibration model at the magnetic bearing position is obtained; the position information of the rotor is obtained in real time. In an actual system, the geometric center position of the rotor cannot be directly measured, and needs to be obtained through a displacement sensor and converted into a displacement measurement signal at the magnetic bearing position; based on the unbalanced vibration model and the displacement measurement signal, the sensor plane rotor position information obtained by the displacement sensor is converted into a formula through coordinate transformation, and is brought into the unbalanced vibration model, and the system model is simplified based on the idea of ​​disturbance separation; based on the system model, a disturbance separation extended state observer assisted by system model information is established.

[0044] Correspondingly, this embodiment provides a method for analyzing the operation of a magnetic levitation molecular pump based on digital twins, establishes a three-dimensional model of a magnetic levitation molecular pump through modeling software, and constructs a digital twin model mapping system; constructs a molecular pump physical system, including a magnetic levitation molecular pump and a temperature sensor, a current sensor, a displacement sensor, a molecular pump speed sensor, a vibration sensor and a vacuum gauge, wherein the temperature sensor, the current sensor and the displacement sensor are integrated on the axial magnetic bearing and the radial magnetic bearing; constructs a digital twin information processing system, including a data storage module, a control module and a data processing module; the data storage module is used to store the original parameters and real-time changing parameters of the molecular pump; during operation, the data of each sensor is obtained through the molecular pump controller, and sent to the data processing module through the communication module, the data processing module calculates the real-time parameters obtained and generates a status result, and the control module updates and presents the three-dimensional model of the magnetic levitation molecular pump in real time according to the generated status result, and issues an early warning when data abnormality occurs. Its specific construction method and working process are as described above, and no further explanation is given here to avoid repetition.

[0045] The above description is combined with the accompanying drawings to fully illustrate the specific embodiments of this article so that those skilled in the art can practice them. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of the present invention includes the entire scope of the claims, and all available equivalents of the claims. In the present invention, the terms "first", "second", etc. are only used to distinguish one element from another, without requiring or implying any actual relationship or order between these elements. In fact, the first element can also be called the second element, and vice versa. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the structure, device or equipment including a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also include elements inherent to such structure, device or equipment. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the structure, device or equipment including the elements. Each embodiment is described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other.

[0046] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

[0047] Although the above describes the specific implementation methods of the present invention, it is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art on the basis of the technical solution of the present invention without creative work are still within the scope of protection of the present invention.

Claims

1. A magnetic levitation molecular pump operation analysis system based on digital twin, characterized by: It includes a molecular pump physical system, a digital twin model mapping system and a digital twin information processing system; the molecular pump physical system includes a magnetic levitation molecular pump and a temperature sensor, a current sensor, a displacement sensor, a molecular pump speed sensor, a vibration sensor and a vacuum gauge, and the temperature sensor, the current sensor and the displacement sensor are integrated on the axial magnetic bearing and the radial magnetic bearing; the digital twin model mapping system includes a three-dimensional model of the magnetic levitation molecular pump established by three-dimensional modeling software and a human-computer interaction interface, which is used to present real-time molecular pump state changes; the digital twin information processing system includes a data storage module, a control module and a data processing module, the data storage module is used to store the original parameters and real-time changing parameters of the molecular pump, the control module obtains real-time sensor data through the molecular pump controller and sends it to the data processing module, the data processing module calculates the acquired real-time parameters and generates status results, and the control module updates and presents the three-dimensional model of the magnetic levitation molecular pump in real time according to the generated status results.

2. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 1, characterized in that: The three-dimensional model of the magnetic levitation molecular pump established by the three-dimensional modeling software is a modeling of the magnetic levitation molecular pump by solidworks software; the rotor blade disk rotates at high speed, the root of the blade will be affected by a strong centrifugal force, and the centrifugal force on the blade row increases from the inner ring to the outer ring. In order to monitor whether the blade will be damaged during operation, the blade row structure is simulated and analyzed; the three-dimensional model of the rotor disk is drawn by SolidWorks software and saved in x_t format, and the Static Structural module in ANSYS WorkBench software is used to import the three-dimensional model of the rotor, set the rotor material properties and rated speed, and select the bearing support point at the design position, simulate and analyze the stress, strain and displacement of the blade, and present it in the digital twin model mapping system.

3. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 1, characterized in that: The digital twin model mapping system is integrated with an early warning module, with a temperature setting range of 5°C to 35°C. When the temperature obtained by the temperature sensor exceeds 35°C, an early warning is issued.

4. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 1, characterized in that: The displacement sensors are provided with 9 groups; the magnetic levitation molecular pump comprises a first radial magnetic bearing, a second radial magnetic bearing and an axial magnetic bearing, the first radial magnetic bearing constructs an XY axis coordinate of a two-dimensional plane, wherein 4 groups of displacement sensors are respectively arranged relatively on the XY axis coordinate; the second radial magnetic bearing constructs an AB axis coordinate of a two-dimensional plane, wherein 4 groups of displacement sensors are respectively arranged relatively on the AB axis coordinate; the axial magnetic bearing is a Z axis along the axial direction, and a group of displacement sensors is arranged below it; the 9 groups of displacement sensors obtain the five-axis coordinate position in real time and send it to the data processing module, the data processing module calculates the obtained real-time data and generates a status result, presents it on the three-dimensional model of the magnetic levitation molecular pump, and records the abnormal result in the data storage module for later maintenance.

5. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 1, characterized in that: The current sensor is used to obtain the real-time current of the coils of the radial magnetic bearing and the axial magnetic bearing, and compare it with the factory-preset rotor suspension control current stored in the storage module. When an abnormality occurs, an early warning is issued through the early warning module of the twin model mapping system.

6. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 1, characterized in that: The vacuum gauge is used to obtain the vacuum degree when the magnetic levitation molecular pump is running. The data processing module can generate a change curve graph of the change of the vacuum degree, which can be recorded in the data storage module and presented through the human-computer interaction interface.

7. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 4, characterized in that: The data storage module stores a disturbance separation extended state observer model. Based on the disturbance separation extended state observer, the displacement, imbalance and other disturbance parameters of each channel are obtained and presented in the digital twin model mapping system. The construction method of the disturbance separation extended state observer model is: Acquire a rotor dynamics model at the mass center position; acquire an unbalanced vibration model at the magnetic bearing position based on the rotor dynamics model; acquire rotor position information in real time and convert it into a displacement measurement signal at the magnetic bearing position; establish a system model based on the unbalanced vibration model and the displacement measurement signal; Based on the system model, a disturbance separation extended state observer assisted by system model information is established.

8. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 1, characterized in that: The molecular pump speed sensor is used to obtain the real-time speed of the rotor when the magnetic suspension molecular pump is running. The data processing module can generate a change curve chart of the change in speed, which can be recorded in the data storage module and presented through the human-computer interaction interface.

9. The magnetic levitation molecular pump operation analysis system based on digital twin according to claim 1, characterized in that: The vibration sensor is fixed to the outside of the molecular pump housing through a magnetic base, and is used to obtain the transient value of the rotor vibration amplitude, and generate a floating waveform diagram of the magnetically suspended rotor in a certain degree of freedom direction by a waveform analysis method through a data processing module, which is recorded in the data storage module and presented through a human-computer interaction interface. The user can judge the abnormal situation of the rotor through the waveform diagram; For simple harmonic oscillation, the mathematical equation for the waveform is: x(t)=A sin(wt+φ)=A sin(2πft+φ) In the formula, A is the vibration peak, also known as the single amplitude, which reflects the size of the vibration; w is the angular frequency, which indicates the speed of vibration, and the larger the unit is rad / sw, the faster the vibration; f is the frequency, and the unit is hertz, f=w / 2π; the reciprocal of f is called the period T, and the unit is second S; φ is the initial phase angle, and φ reflects the starting position of the waveform. When φ>0, it is called phase lead; when φ<0, it is called phase lag; x(t) is the instantaneous amplitude of the vibration, and the unit is the same as A; taking a certain point on the rotor as the phase reference point, the relative position relationship between each transient value on the vibration waveform and each point on the rotor can be known, and the peak-to-peak value can be used to indicate the maximum amplitude of the vibration; the rotor vibration waveform is synthesized by many simple harmonic vibration components; the synthesis of two simple harmonic waves with the same frequency is still a simple harmonic waveform of the same frequency, but the amplitude and phase change.

10. A method for analyzing the operation of a magnetic levitation molecular pump based on digital twins, characterized in that: And includes the following process: A three-dimensional model of a magnetic levitation molecular pump is established through modeling software, and a digital twin model mapping system is constructed; a molecular pump physical system is constructed, including a magnetic levitation molecular pump and a temperature sensor, a current sensor, a displacement sensor, a molecular pump speed sensor, a vibration sensor and a vacuum gauge, wherein the temperature sensor, the current sensor and the displacement sensor are integrated on the axial magnetic bearing and the radial magnetic bearing; a digital twin information processing system is constructed, including a data storage module, a control module and a data processing module; the data storage module is used to store the original parameters of the molecular pump and the real-time changing parameters; During operation, the data of each sensor is obtained through the molecular pump controller and sent to the data processing module through the communication module. The data processing module calculates the acquired real-time parameters and generates status results. The control module updates and presents the three-dimensional model of the magnetic levitation molecular pump in real time according to the generated status results. When data abnormalities occur, an early warning is issued.

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