Detection and control device and method for radial runout of main shaft of shield pump

Abstract

The invention discloses a shield pump spindle radial run-out detection and control device and method, and relates to the field of spindle radial run-out detection and control. A detection and control device for radial runout of a main shaft of a shield pump comprises a magnetic ring installed on the outer side of the main shaft of the shield pump and a magnetoresistive sensor installed on the inner wall of a pump body of the shield pump and used for detecting the change of the magnetic field intensity generated by the rotating magnetic ring. The two groups of magnetoresistive sensors are orthogonally distributed on the inner wall of a pump body, the magnetic ring is mounted on one side, close to an input end, of a main shaft of the shield pump, and the stainless steel lining is mounted on the inner side of the magnetic ring and is in interference fit with the magnetic ring through a hot jacket process; according to the invention, non-contact measurement and two groups of orthogonally distributed magnetoresistive sensors are adopted to detect the magnetic field change of the surface of the main shaft, the main shaft is not required to be contacted, the influence on the operation of the main shaft is avoided, the measurement error is reduced, and real-time monitoring is facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of spindle radial runout detection and control, and in particular relates to a device and method for detecting and controlling the radial runout of a canned motor pump spindle. Background Art

[0002] Conventional radial inspection and control of canned motor pump spindles typically relies on contact measurement. Traditional methods often employ contact measuring tools, such as micrometers, to directly contact the spindle surface for radial runout detection. This method has the following drawbacks: 1. Measurement accuracy is compromised: contact forces can affect the actual operating state of the spindle, leading to measurement errors; 2. Operational inconvenience: manual operation is required, resulting in low efficiency and requiring high operator skills; 3. Online monitoring is difficult: real-time monitoring of the spindle during operation is impossible. Summary of the Invention

[0003] The purpose of the present invention is to solve the problems in the prior art and to propose a detection and control device and method for radial runout of a shielded pump main shaft.

[0004] In order to solve the above technical problems, the basic concept of the technical solution adopted by the present invention is:

[0005] A device for detecting and controlling radial runout of a canned motor pump main shaft comprises a magnetic ring mounted on the outside of the canned motor pump main shaft, and a magnetoresistive sensor mounted on the inner wall of the canned motor pump body for detecting changes in magnetic field intensity generated by the rotating magnetic ring.

[0006] The magnetoresistive sensors are provided in two groups and are orthogonally distributed on the inner wall of the pump body.

[0007] Preferably, the magnetic ring is installed on the side of the shielded pump main shaft close to the input end, and a stainless steel bushing is installed on the inner side of the magnetic ring. The stainless steel bushing is interference fit with the magnetic ring through a shrink fitting process.

[0008] Preferably, the outer side of the shielded pump main shaft and the inner side of the stainless steel bushing are provided with corresponding keyways, and key blocks are installed in the keyways. The key blocks are inserted into the two corresponding keyways, so that the stainless steel bushing is rigidly connected to the shielded pump main shaft, ensuring that the magnetic ring and the shielded pump main shaft rotate strictly synchronously.

[0009] Preferably, a fluororubber skeleton oil seal is installed between the outer side of the stainless steel bushing of the magnetic ring and the inner side of the pump body to prevent the medium from penetrating into the magnetic ring area.

[0010] A method for detecting and controlling radial runout of a canned motor pump main shaft comprises the following steps:

[0011] S1: The stainless steel bushing and the magnetic ring are fixed to the main shaft of the shielded pump by typing the key block into the keyway. After magnetization, the magnetic ring has N poles and S poles alternately distributed on its circumference, forming a periodically changing stable magnetic field. The magnetic field direction of each magnetic pole is perpendicular to the main shaft surface of the shielded pump.

[0012] S2: When the canned motor pump spindle is stationary, a gauss meter is used to measure the magnetic field strength on the surface of the magnetic ring, and the baseline data of the magnetic field distribution at each magnetic pole is recorded as a reference for subsequent signal processing. When the canned motor pump spindle drives the magnetic ring to rotate, the magnetic field strength in the surrounding space will change periodically with the angle. Two orthogonally distributed magnetoresistive sensors are then used to detect the magnetic field changes generated by the rotation of the magnetic ring.

[0013] S3: When the canned motor pump main shaft rotates, the magnetic ring rotates accordingly, and the N / S poles of the magnetic ring alternately pass through the position of the magnetoresistive sensor. The periodic arrangement of the magnetic poles on its surface causes the direction and intensity of the surrounding magnetic field at the installation point of the magnetoresistive sensor to change periodically over time. If there is radial runout of the canned motor pump main shaft, the rotation trajectory of the magnetic ring will deviate from the ideal center of the circle, and the actual rotation radius of the magnetic ring will fluctuate, resulting in deviations in the amplitude and phase of the magnetic field change.

[0014] Preferably, the magnetoresistive sensor is also electrically connected to a detection and control system for performing radial runout detection on its derived signal; the detection and control system includes a processing unit for preprocessing the derived signal of the magnetoresistive sensor, the processing unit includes a signal amplification module, a bandpass filtering module, a digital-to-analog conversion module, a frequency domain analysis and feature extraction model, and a runout calculation model, the frequency domain analysis and feature extraction model integrates an FFT algorithm and an adaptive notch filtering module, and the runout calculation model includes X / Y direction displacement solution and radial runout synthesis.

[0015] Preferably, the method further comprises the following steps:

[0016] A1: The electrical signal output by the magnetoresistive sensor first passes through the signal amplification module of the processing unit, which amplifies the microvolt-level signal emitted by the magnetoresistive sensor by times. The high-frequency noise and low-frequency drift are filtered out by the bandpass filter module. The amplified and filtered electrical signal is converted into a digital signal by the digital-to-analog conversion module. The converted signal is then subjected to a fast Fourier transform using the FFT algorithm of the frequency domain analysis and feature extraction model to extract the fundamental frequency (f0) of the canned motor pump main shaft rotation and its harmonic components. At the same time, the adaptive notch filter module is used to filter out non-synchronous interference frequencies in the signal, such as bearing vibration noise, and retain the frequency band related to runout.

[0017] A2: The data processed by the frequency domain analysis and feature extraction model is imported into the runout calculation model. The X / Y direction displacement solution in the runout calculation model calculates the instantaneous displacement ΔX and ΔY of the shielded pump main shaft in the X and Y directions based on the signal phase difference and amplitude of the two orthogonally set magnetic resistance sensors. Among them, A_x and A_y are the displacement amplitudes, φ_x and φ_y are the phase angles. The calculated instantaneous displacements are synthesized, and the X / Y direction displacement is calculated to calculate the total radial runout R. In one rotation cycle, the difference between the maximum and minimum values ​​of R is the peak value of the radial runout, and the runout amplitude is obtained through the peak value.

[0018] Preferably, the jitter calculation model is electrically connected to a monitoring unit, and the monitoring unit includes:

[0019] B1: Threshold alarm:

[0020] Preset radial runout safety threshold: When the peak value calculated in real time exceeds the threshold, an audible and visual alarm is triggered and a shutdown signal is output;

[0021] Adaptive threshold: The machine learning model learns historical data and automatically adjusts the threshold to reduce false positives.

[0022] B2: Data visualization and output:

[0023] Real-time display: transmit data to the display for easy observation;

[0024] Industrial communications: Transmit data to the cloud for remote monitoring.

[0025] After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: the present invention;

[0026] The invention relates to a detection and control device for radial runout of a shielded pump main shaft. The device adopts non-contact measurement. Two groups of orthogonally distributed magnetoresistive sensors detect the magnetic field changes on the main shaft surface. There is no need to contact the main shaft, thus avoiding the influence on the operation of the main shaft, reducing the measurement error and facilitating real-time monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In the attached figure:

[0028] Figure 1 This is a main view of a shielded pump main shaft of a device for detecting and controlling radial runout of a shielded pump main shaft proposed by the present invention;

[0029] Figure 2 The present invention proposes a detection and control device for the radial runout of the shielded pump main shaft Figure 1 sectional view of

[0030] Figure 3 The present invention proposes a detection and control device for the radial runout of the shielded pump main shaft Figure 1Schematic diagram of the decomposition;

[0031] Figure 4 This is a schematic diagram of electrical connections for a method for detecting and controlling radial runout of a canned motor pump main shaft proposed by the present invention;

[0032] Figure 5 This is a schematic diagram of the working principle of a method for detecting and controlling radial runout of a canned motor pump main shaft proposed by the present invention;

[0033] Figure 6 The present invention provides a schematic diagram of the workflow of a method for detecting and controlling radial runout of a shielded pump main shaft.

[0034] In the figure: 1. Pump body; 2. Shielded pump main shaft; 201. Magnetic ring; 202. Stainless steel bushing; 203. Keyway; 204. Key block; 205. Fluororubber skeleton oil seal; 3. Magnetoresistive sensor; 4. Inspection and control system; 5. Processing unit; 6. Signal amplification module; 7. Bandpass filter module; 8. Digital-to-analog conversion module; 9. Frequency domain analysis and feature extraction model; 901. FFT algorithm; 902. Adaptive notch filter module; 10. Runout calculation model; 101. X / Y direction displacement solution; 102. Radial runout synthesis; 11. Monitoring unit. DETAILED DESCRIPTION

[0035] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments so that those skilled in the art can implement the invention with reference to the description.

[0036] It should be understood that terms such as “having”, “including” and “comprising” used herein do not preclude the existence or addition of one or more other elements or combinations thereof.

[0037] In the description of the present invention, the terms "horizontal", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like to indicate orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0038] Example 1: Reference Figure 1 - Figure 3A device for detecting and controlling radial runout of a shielded pump main shaft comprises a shielded pump body 1 and a shielded pump main shaft 2 installed inside the pump body 1. A magnetic ring 201 is provided on the outer wall of the shielded pump main shaft 2. A stainless steel bushing 202 is installed on the inner side of the magnetic ring 201. The magnetic ring 201 and the stainless steel bushing 202 are interference-fitted by a shrink-fit process. The stainless steel bushing 202 is inserted into a keyway 203 through a key block 204 and rigidly connected to the shielded pump main shaft 2 to ensure that the magnetic ring 201 and the shielded pump main shaft 2 rotate strictly synchronously. After installation, a dynamic balance test is performed on the shielded pump main shaft 2 to avoid additional vibration introduced by the magnetic ring 201.

[0039] Two orthogonally distributed magnetoresistive sensors 3 (in the X-axis and Y-axis directions) are installed on the pump body 1. The magnetoresistive sensors 3 maintain a gap of 0.5-1 mm (non-contact) with the outer cylindrical axis of the magnetic ring 201. The magnetoresistive sensors 3 are based on the magnetoresistive effect. Their resistance value changes with the direction of the external magnetic field, and they output a voltage signal proportional to the magnetic field strength. By setting up an orthogonal layout of the two magnetoresistive sensors 3, the two-dimensional component of the radial runout of the canned motor pump main shaft 2 can be solved, eliminating the directional error of single-point measurement.

[0040] A fluororubber skeleton oil seal 205 is provided at the gap between the magnetic ring 201 and the pump body 1 to prevent the medium from penetrating into the magnetic ring 201 area;

[0041] Working Principle: A magnetic ring 201 is fixedly mounted on the surface of the canned pump main shaft 2. After magnetization, the magnetic ring 201 has alternating N and S poles distributed around its circumference, forming a periodically changing stable magnetic field. The magnetic field direction of each magnetic pole is perpendicular to the surface of the canned pump main shaft 2. When the canned pump main shaft 2 is stationary, a gaussmeter is used to measure the magnetic field strength on the surface of the magnetic ring 201, and the magnetic field distribution baseline data of each magnetic pole is recorded as a reference for subsequent signal processing. When the canned pump main shaft 2 drives the magnetic ring 201 to rotate, the magnetic field strength in the surrounding space changes periodically with the angle. Two orthogonally distributed magnetoresistive sensors 3 then detect the magnetic field changes generated by the rotation of the magnetic ring 201.

[0042] When the canned motor pump main shaft 2 rotates, the magnetic ring 201 rotates accordingly. The N / S poles of the magnetic ring 201 alternately pass through the position of the magnetoresistive sensor 3. The periodic arrangement of the magnetic poles on its surface causes the direction and intensity of the surrounding magnetic field at a fixed position (the installation point of the magnetoresistive sensor 3) to change periodically over time. If the canned motor pump main shaft 2 has radial runout, the rotation trajectory of the magnetic ring 201 will deviate from the ideal center of the circle, and the actual rotation radius of the magnetic ring 201 will fluctuate, resulting in deviations in the amplitude and phase of the magnetic field change.

[0043] If there is no radial runout of the canned motor pump main shaft 2, the sine wave output by the magnetic resistance sensor 3 has a constant amplitude and a frequency consistent with the rotational speed;

[0044] If there is radial runout of the canned motor pump main shaft 2, the amplitude of the sine wave fluctuates, and a slight phase shift occurs in the waveform period;

[0045] Example 2: A method for detecting and controlling radial runout of a shielded pump main shaft, referring to Figure 1 - Figure 6 On the basis of the first embodiment, further, the magnetoresistive sensor 3 is electrically connected to a detection and control system 4, which includes a processing unit 5 for preprocessing the signal derived from the magnetoresistive sensor 3. The processing unit 5 includes a signal amplification module 6, a bandpass filtering module 7, a digital-to-analog conversion module 8, a frequency domain analysis and feature extraction model 9, and a runout calculation model 10. The frequency domain analysis and feature extraction model 9 integrates an FFT algorithm 901 and an adaptive notch filtering module 902. The runout calculation model 10 includes an X / Y direction displacement solution 101 and a radial runout synthesis 102.

[0046] Working Principle: A magnetic ring 201 is fixedly mounted on the surface of the canned pump main shaft 2. After magnetization, the magnetic ring 201 has alternating N and S poles distributed around its circumference, forming a periodically changing stable magnetic field. The magnetic field direction of each magnetic pole is perpendicular to the surface of the canned pump main shaft 2. When the canned pump main shaft 2 is stationary, a gaussmeter is used to measure the magnetic field strength on the surface of the magnetic ring 201, and the magnetic field distribution baseline data of each magnetic pole is recorded as a reference for subsequent signal processing. When the canned pump main shaft 2 drives the magnetic ring 201 to rotate, the magnetic field strength in the surrounding space changes periodically with the angle. Two orthogonally distributed magnetoresistive sensors 3 then detect the magnetic field changes generated by the rotation of the magnetic ring 201.

[0047] When the canned motor pump main shaft 2 rotates, the magnetic ring 201 rotates accordingly. The N / S poles of the magnetic ring 201 alternately pass through the position of the magnetoresistive sensor 3. The periodic arrangement of the magnetic poles on its surface causes the direction and intensity of the surrounding magnetic field at a fixed position (the installation point of the magnetoresistive sensor 3) to change periodically over time. If the canned motor pump main shaft 2 has radial runout, the rotation trajectory of the magnetic ring 201 will deviate from the ideal center of the circle, and the actual rotation radius of the magnetic ring 201 will fluctuate, resulting in deviations in the amplitude and phase of the magnetic field change.

[0048] If there is no radial runout of the canned motor pump main shaft 2, the sine wave output by the magnetic resistance sensor 3 has a constant amplitude and a frequency consistent with the rotational speed;

[0049] If there is radial runout of the canned motor pump main shaft 2, the amplitude of the sine wave fluctuates, and a slight phase shift occurs in the waveform period;

[0050] The electrical signal output by the magnetoresistive sensor 3 first passes through the signal amplification module 6, which amplifies the microvolt signal emitted by the magnetoresistive sensor 3 by 100 times, and filters out high-frequency noise and low-frequency drift through the bandpass filter module 7. The amplified and filtered electrical signal is converted into a digital signal through the digital-to-analog conversion module 8, and then the converted signal is subjected to fast Fourier transform through the FFT algorithm 901 of the frequency domain analysis and feature extraction model 9 to extract the fundamental frequency (f0) of the rotation of the shielded pump main shaft 2 and its harmonic components. At the same time, the adaptive notch filter module 902 is used to filter out the non-synchronous interference frequency in the signal, such as bearing vibration noise, and retain the signal with the jump. The frequency band related to the movement is processed by the frequency domain analysis and feature extraction model 9 and is imported into the runout calculation model 10. The X / Y direction displacement solution 101 of the runout calculation model 10 calculates the instantaneous displacements ΔX and ΔY of the shielded pump main shaft 2 in the X and Y directions according to the signal phase difference and amplitude of the two orthogonally arranged magnetoresistive sensors 3, wherein A_x and A_y are the displacement amplitudes, φ_x and φ_y are the phase angles, and the calculated instantaneous displacements are synthesized to calculate the X / Y direction displacement and the total radial runout R. In one rotation cycle, the difference between the maximum and minimum values ​​of R is the peak value of the radial runout, and the runout amplitude is obtained by the peak value.

[0051] Example 3: Reference Figure 1 - Figure 6 , which is basically the same as Example 2, but further includes: a monitoring unit 11 electrically connected to the jitter calculation model 10, and the monitoring unit 11 includes: 1. Threshold alarm:

[0052] Preset radial runout safety threshold: When the peak value calculated in real time exceeds the threshold, an audible and visual alarm is triggered and a shutdown signal is output;

[0053] Adaptive threshold: The machine learning model learns historical data and automatically adjusts the threshold to reduce false positives.

[0054] 2. Data visualization and output:

[0055] Real-time display: transmit data to the display for easy observation;

[0056] Industrial communications: Transmit data to the cloud for remote monitoring.

[0057] Working Principle: A magnetic ring 201 is fixedly mounted on the surface of the canned pump main shaft 2. After magnetization, the magnetic ring 201 has alternating N and S poles distributed around its circumference, forming a periodically changing stable magnetic field. The magnetic field direction of each magnetic pole is perpendicular to the surface of the canned pump main shaft 2. When the canned pump main shaft 2 is stationary, a gaussmeter is used to measure the magnetic field strength on the surface of the magnetic ring 201, and the magnetic field distribution baseline data of each magnetic pole is recorded as a reference for subsequent signal processing. When the canned pump main shaft 2 drives the magnetic ring 201 to rotate, the magnetic field strength in the surrounding space changes periodically with the angle. Two orthogonally distributed magnetoresistive sensors 3 then detect the magnetic field changes generated by the rotation of the magnetic ring 201.

[0058] When the canned motor pump main shaft 2 rotates, the magnetic ring 201 rotates accordingly. The N / S poles of the magnetic ring 201 alternately pass through the position of the magnetoresistive sensor 3. The periodic arrangement of the magnetic poles on its surface causes the direction and intensity of the surrounding magnetic field at a fixed position (the installation point of the magnetoresistive sensor 3) to change periodically over time. If the canned motor pump main shaft 2 has radial runout, the rotation trajectory of the magnetic ring 201 will deviate from the ideal center of the circle, and the actual rotation radius of the magnetic ring 201 will fluctuate, resulting in deviations in the amplitude and phase of the magnetic field change.

[0059] If there is no radial runout of the canned motor pump main shaft 2, the sine wave output by the magnetic resistance sensor 3 has a constant amplitude and a frequency consistent with the rotational speed;

[0060] If there is radial runout of the canned motor pump main shaft 2, the amplitude of the sine wave fluctuates, and a slight phase shift occurs in the waveform period;

[0061] The electrical signal output by the magnetoresistive sensor 3 first passes through the signal amplification module 6, which amplifies the microvolt signal emitted by the magnetoresistive sensor 3 by 100 times, and filters out high-frequency noise and low-frequency drift through the bandpass filter module 7. The amplified and filtered electrical signal is converted into a digital signal through the digital-to-analog conversion module 8, and then the converted signal is subjected to fast Fourier transform through the FFT algorithm 901 of the frequency domain analysis and feature extraction model 9 to extract the fundamental frequency (f0) of the rotation of the shielded pump main shaft 2 and its harmonic components. At the same time, the adaptive notch filter module 902 is used to filter out the non-synchronous interference frequency in the signal, such as bearing vibration noise, and retain the signal with the jump. The frequency band related to the movement is analyzed and the data processed by the frequency domain analysis and feature extraction model 9 is imported into the runout calculation model 10. The X / Y direction displacement solution 101 of the runout calculation model 10 calculates the instantaneous displacements ΔX and ΔY of the shielded pump main shaft 2 in the X and Y directions according to the signal phase difference and amplitude of the two orthogonally arranged magnetoresistive sensors 3, wherein A_x and A_y are the displacement amplitudes, φ_x and φ_y are the phase angles, and the calculated instantaneous displacements are synthesized to calculate the X / Y direction displacement and the total radial runout R. Within one rotation cycle, the difference between the maximum and minimum values ​​of R is the peak value of the radial runout, and the runout amplitude is obtained through the peak value.

[0062] The above embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patented invention. It should be noted that those skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention. These variations and improvements are equivalent modifications and improvements to the above embodiments based on the essential technology of the present invention and fall within the scope of protection of the present invention.

Claims

1. A detection and control device for radial runout of a canned motor pump main shaft, characterized in that: The invention comprises a magnetic ring (201) installed on the outside of a shielded pump main shaft (2), and a magnetoresistive sensor (3) installed on the inner wall of a pump body (1) of the shielded pump for detecting changes in magnetic field intensity generated by the rotating magnetic ring (201); The magnetoresistive sensors (3) are provided in two groups and are orthogonally distributed on the inner wall of the pump body (1).

2. A detection and control device for radial runout of a shielded pump main shaft according to claim 1, characterized in that: The magnetic ring (201) is installed on a side of the shielded pump main shaft (2) close to the input end, and a stainless steel bushing (202) is installed on the inner side of the magnetic ring (201). The stainless steel bushing (202) is interference-fitted with the magnetic ring (201) through a shrink-fit process.

3. The device for detecting and controlling radial runout of a canned motor pump main shaft according to claim 2, characterized in that: The outer side of the shielded pump main shaft (2) and the inner side of the stainless steel bushing (202) are both provided with corresponding keyways (203), and key blocks (204) are installed in the keyways (203). The key blocks (204) are inserted into the two corresponding keyways (203), so that the stainless steel bushing (202) and the shielded pump main shaft (2) are rigidly connected, ensuring that the magnetic ring (201) and the shielded pump main shaft (2) rotate strictly synchronously.

4. The device for detecting and controlling radial runout of a canned motor pump main shaft according to claim 3, characterized in that: A fluororubber skeleton oil seal (205) is installed between the outer side of the stainless steel bushing (202) of the magnetic ring (201) and the inner side of the pump body (1) to prevent the medium from penetrating into the magnetic ring (201) area.

5. A method for detecting and controlling radial runout of a canned motor pump main shaft, applied to a device for detecting and controlling radial runout of a canned motor pump main shaft according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1: A stainless steel bushing (202) and a magnetic ring (201) are fixed to the shielded pump main shaft (2) by inserting a key block (204) into a keyway (203). After magnetization, the magnetic ring (201) has N poles and S poles alternately distributed on its circumference, forming a periodically changing stable magnetic field. The magnetic field direction of each magnetic pole is perpendicular to the surface of the shielded pump main shaft (2); S2: When the shielded pump main shaft (2) is stationary, a gauss meter is used to measure the magnetic field intensity on the surface of the magnetic ring (201), and the magnetic field distribution baseline data of each magnetic pole is recorded to be used as a reference for subsequent signal processing; when the shielded pump main shaft (2) drives the magnetic ring (201) to rotate, the magnetic field intensity in the surrounding space will change periodically with the angle, and then two orthogonally distributed magnetoresistive sensors (3) detect the magnetic field changes generated by the rotation of the magnetic ring (201); S3: When the shielded pump main shaft (2) rotates, the magnetic ring (201) rotates accordingly, and the N / S level of the magnetic ring (201) alternately passes through the position of the magnetoresistive sensor (3). The periodic arrangement of the magnetic poles on its surface causes the direction and intensity of the magnetic field of the surrounding magnetic field at the installation point of the magnetoresistive sensor (3) to change periodically with time. If the shielded pump main shaft (2) has radial runout, the rotation trajectory of the magnetic ring (201) will deviate from the ideal center of the circle, and the actual rotation radius of the magnetic ring (201) will fluctuate, resulting in deviations in the amplitude and phase of the magnetic field change.

6. A method for detecting and controlling radial runout of a canned motor pump main shaft according to claim 5, characterized in that: The magnetoresistive sensor (3) is also electrically connected to a detection and control system (4) for performing radial runout detection on its derived signal; the detection and control system (4) includes a processing unit (5) for preprocessing the derived signal of the magnetoresistive sensor (3); the processing unit (5) includes a signal amplification module (6), a bandpass filtering module (7), a digital-to-analog conversion module (8), a frequency domain analysis and feature extraction model (9), and a runout calculation model (10); the frequency domain analysis and feature extraction model (9) integrates an FFT algorithm (901) and an adaptive notch filtering module (902); and the runout calculation model (10) includes an X / Y direction displacement solution (101) and a radial runout synthesis (102).

7. A method for detecting and controlling radial runout of a canned motor pump main shaft according to claim 6, characterized in that: The following steps are also included: A1: The electrical signal output by the magnetoresistive sensor (3) first passes through the signal amplification module (6) of the processing unit (5), amplifying the microvolt-level signal emitted by the magnetoresistive sensor (3) by 100 times, and filtering out high-frequency noise and low-frequency drift through the bandpass filter module (7). The amplified and filtered electrical signal is converted into a digital signal through the digital-to-analog conversion module (8), and then the converted signal is subjected to fast Fourier transformation through the FFT algorithm (901) of the frequency domain analysis and feature extraction model (9) to extract the fundamental frequency (f0) of the rotation of the shielded pump main shaft (2) and its harmonic components. At the same time, the adaptive notch filter module (902) is used to filter out the non-synchronous interference frequency in the signal, such as bearing vibration noise, and retain the frequency band related to the runout; A2: The data processed by the frequency domain analysis and feature extraction model (9) is imported into the runout calculation model (10). The X / Y direction displacement solution (101) in the runout calculation model (10) calculates the instantaneous displacement ΔX and ΔY of the shielded pump main shaft (2) in the X and Y directions based on the signal phase difference and amplitude of the two orthogonally arranged magnetic resistance sensors (3).

8. A method for detecting and controlling radial runout of a canned motor pump main shaft according to claim 7, characterized in that: in, A_x and A_y are displacement amplitudes, φ_x and φ_y are phase angles, and the calculated instantaneous displacements are synthesized to calculate the displacement in the X / Y direction and the total radial runout R.

9. A method for detecting and controlling radial runout of a canned motor pump main shaft according to claim 8, characterized in that: In one rotation cycle, the difference between the maximum and minimum values ​​of R is the peak value of radial runout, and the runout amplitude is obtained from the peak value.

10. A method for detecting and controlling radial runout of a canned motor pump main shaft according to claim 9, characterized in that: The jitter calculation model (10) is electrically connected to a monitoring unit (11), and the monitoring unit (11) includes: B1: Threshold alarm: Preset radial runout safety threshold: When the peak value calculated in real time exceeds the threshold, an audible and visual alarm is triggered and a shutdown signal is output; Adaptive threshold: The machine learning model learns historical data and automatically adjusts the threshold to reduce false positives. B2: Data visualization and output: Real-time display: transmit data to the display for easy observation; Industrial communications: Transmit data to the cloud for remote monitoring.

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