Magnetic suspension pump rotor space attitude detection method and device

Abstract

The invention discloses a magnetic suspension pump rotor space attitude detection method and device. Four Hall sensors are orthogonally installed in two planes under an air gap of the magnetic suspension pump respectively, and voltage signals generated in different planes and different directions when a rotor moves are detected through the Hall sensors. Hall signals, collected by a plane closer to the rotor, in x and y directions are subjected to difference and arc tangent to obtain a rotation angle of the rotor in the radial direction; hall signals, collected by the two planes, in the x direction and the y direction are subjected to information obtaining and processing through a four-sensing second-order differential amplification circuit, the difference value of Hall voltage signals, generated by inclination of the rotor, in the x direction and the y direction is obtained, then axial displacement generated when the rotor inclines is obtained, and the inclination angle of the rotor around the x plane and the y plane is obtained according to the geometrical relationship. The method and the device provided by the invention are simpler in structure and very high in data calculation accuracy and efficiency.

Description

Technical Field

[0001] The invention relates to a magnetic suspension pump rotor detection method in the field of magnetic suspension pump sensing, and in particular to a magnetic suspension pump rotor space posture detection method and device. Background Art

[0002] Magnetic levitation pumps are widely used in semiconductor manufacturing, biomedical processing and other fields. Because they have no bearings, no mechanical friction, and continuous, smooth and pulsation-free flow, they have been widely used in these industries that require an ultra-clean working environment. However, due to its bearingless structural characteristics, compared with traditional permanent magnet synchronous motors, an additional set of suspension windings is required to ensure the suspension of the rotor; in addition, due to the mutual interference of the magnetic fields generated by the suspension windings and the drive windings, the control of the suspension and drive of the magnetic levitation pump rotor is also difficult. Accurately measuring the spatial posture of the magnetic levitation pump rotor is a prerequisite for achieving stable control. However, due to the compact structure and limited space of the magnetic levitation pump, it is difficult to obtain the entire spatial posture of the rotor through direct measurement by sensors, especially the inclination angle of the rotor. Therefore, a new detection method is needed to measure the spatial posture of the magnetic levitation pump rotor. Summary of the invention

[0003] In order to solve the problem in the background technology, the present invention provides a method for measuring the spatial posture of a suspended rotor in a magnetic levitation pump. The present invention collects signals through two pairs of orthogonally distributed Hall sensors located in two planes, and performs double-order differential amplification to obtain the difference of the magnetic induction intensity signal in the axial direction, and then calculates the inclination angle of the rotor; the rotation angle of the rotor is obtained by performing differential and inverse tangent on the signal value of the Hall sensor closer to the rotor plane.

[0004] The technical solution adopted by the present invention is:

[0005] 1. A method for detecting the spatial posture of a magnetic levitation pump rotor

[0006] Step 1: Install two sets of Hall detection units on the inner side wall of the stator teeth of the magnetic levitation pump. The two sets of Hall detection units are arranged vertically opposite to each other, and the planes where the two sets of Hall detection units are located are parallel and spaced apart; each set of Hall detection units includes four Hall sensors arranged at equal intervals along the circumference;

[0007] Step 2: The rotor of the magnetic levitation pump is suspended and does not move, and the two sets of Hall detection units are subjected to baseline calibration;

[0008] Step 3: After the calibration is completed, two sets of Hall detection units are used to collect Hall signals when the rotor rotates. The rotation angle of the rotor in the XY plane and the tilt angle of the rotor are calculated based on the two sets of Hall detection units, where the XY plane is a plane parallel to the plane where each set of Hall detection units is located.

[0009] The step 2 is specifically as follows:

[0010] The rotor of the magnetic levitation pump is suspended and motionless. First, the N pole and S pole of the rotor are turned toward the X-axis, and the Hall voltage signals of the two groups of Hall detection units corresponding to the X-axis in this state are obtained and used as the X-axis reference Hall voltage. Then, the N pole and S pole of the rotor are turned toward the Y-axis, and the Hall voltage signals of the two groups of Hall detection units corresponding to the Y-axis in this state are obtained and used as the Y-axis reference Hall voltage. The corresponding Hall sensor is subjected to reference calibration according to the X-axis reference Hall voltage and the Y-axis reference Hall voltage.

[0011] The step 3 is specifically as follows:

[0012] After the calibration is completed, the rotation angle of the rotor in the XY plane is calculated based on the Hall voltage signal collected by a group of Hall detection units close to the rotor plane;

[0013] And the tilt angle component of the rotor on the X-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the X-axis corresponding to the two groups of Hall detection units, and the tilt angle component of the rotor on the Y-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the Y-axis corresponding to the two groups of Hall detection units, and then the inclination angle of the rotor is calculated.

[0014] The rotation angle of the rotor in the XY plane is calculated based on the Hall voltage signal collected by a group of Hall detection units close to the rotor plane, specifically:

[0015] The Hall voltage signals collected by a group of Hall detection units close to the rotor plane are respectively the first X-axis Hall voltage U XA1 and the second X-axis Hall voltage U XA2 , the first Y-axis Hall voltage U YA1 and the second Y-axis Hall voltage U YA2 , for the first X-axis Hall voltage U XA1 and the second X-axis Hall voltage U XA2 After differential calculation, the relative Hall voltage U of the X-axis is obtained. X , for the first Y-axis Hall voltage U YA1 and the second Y-axis Hall voltage U YA2 After differential calculation, the Y-axis relative Hall voltage U is obtained. Y , the rotation angle of the rotor in the XY plane is calculated by the following formula

[0016]

[0017] The tilt angle component of the rotor on the X-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the X-axis corresponding to the two groups of Hall detection units, and the tilt angle component of the rotor on the Y-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the Y-axis corresponding to the two groups of Hall detection units, and then the tilt angle of the rotor is calculated, specifically:

[0018] S1: After performing differential calculation on the two X-axis Hall voltages collected by each group of Hall detection units, the corresponding X-axis relative Hall voltage U is obtained. X , and then the X-axis relative Hall voltage U corresponding to the two sets of Hall detection units X After differential calculation, the X-axis Hall voltage signal difference ΔU caused by the rotor tilt is obtained X ;

[0019] S2: After performing differential calculation on the two Y-axis Hall voltages collected by each group of Hall detection units, the corresponding Y-axis relative Hall voltage U is obtained. Y , and then the Y-axis relative Hall voltage U corresponding to the two sets of Hall detection units Y After differential calculation, the Y-axis Hall voltage signal difference ΔU caused by the rotor tilt is obtained Y ;

[0020] S3: Based on the X-axis Hall voltage signal difference ΔU generated by the rotor tilt X The difference ΔU between the Y-axis Hall voltage signal and the rotor tilt Y The axial displacement component Δz caused by the tilt in the X and Y directions is calculated by using the calibrated X-axis deviation-voltage relationship and Y-axis deviation-voltage relationship of the axial position when the rotor is tilted. X , Δz Y ;

[0021] S4: Calculate the rotor inclination angle θ using the following formula:

[0022]

[0023] Among them, θ X The tilt angle component of the rotor on the X-axis, θ Y is the tilt angle component generated on the Y axis, and d is the rotor diameter.

[0024] 2. A device for detecting the spatial posture of a magnetic suspension pump rotor

[0025] The detection device includes a Hall detection unit, a reference correction unit, a first differential amplifier circuit, a dual-order differential amplifier circuit and a signal calculation circuit. Two groups of Hall detection units are installed on the inner side wall of the stator teeth of the magnetic levitation pump. The two groups of Hall detection units are arranged vertically opposite to each other, and the planes where the two groups of Hall detection units are located are parallel and spaced apart. Each group of Hall detection units includes four Hall sensors arranged at equal intervals along the circumference.

[0026] A reference correction unit, used to correct each Hall detection unit according to a reference Hall voltage collected when the rotor of the magnetic levitation pump is suspended and motionless;

[0027] A first differential amplifier circuit, used for performing differential operation on X-axis / Y-axis Hall voltage signals collected by a group of Hall detection units close to the rotor plane and sending corresponding operation results to the signal calculation circuit;

[0028] A dual-stage differential amplifier circuit, used for performing two differential operations on the Hall voltage signals collected by the two groups of Hall detection units and sending the corresponding operation results to the signal calculation circuit;

[0029] The signal calculation circuit is used to calculate the rotation angle of the rotor in the XY plane and the tilt angle of the rotor according to the differential operation sent by the first differential amplifier circuit and the dual-order differential amplifier circuit.

[0030] The dual-order differential amplifier circuit includes two first-stage differential amplifier circuits and one second-stage differential amplifier circuit, the two input ends of each first-stage differential amplifier circuit serve as the input ends of the dual-order differential amplifier circuit, the output ends of the two first-stage differential amplifier circuits are respectively connected to the two input ends of the second-stage differential amplifier circuit, and the output end of the second-stage differential amplifier circuit serves as the output end of the dual-order differential amplifier circuit.

[0031] The beneficial effects of the present invention are:

[0032] 1. The present invention places Hall sensors orthogonally in two planes, and the collected signals of the Hall sensors on both sides of the rotor in the same plane and in the same direction are passed through the front-stage differential amplifier circuit, which can suppress common-mode signals and temperature drift, has the characteristics of self-compensation and linear correction, and can accurately obtain the Hall signal of the magnetic levitation pump rotor in this direction; the rear-stage differential amplifier circuit differentially amplifies the Hall signal values ​​in different planes, can perform denoising and correction, and calculates the inclination angle of the rotor in combination with the rotor radius, which is convenient for analyzing and controlling the state of the rotor during rotation;

[0033] 2. The present invention is based on the same set of detection devices, and performs differential processing on the Hall signal in the plane close to the rotor. The rotation angle of the rotor in the XY plane can be obtained through the inverse tangent function.

[0034] 3. The present invention can simultaneously measure the rotation angle around the Z axis and the tilt angle relative to the XY plane through a set of detection devices, thereby completing the measurement of the spatial posture of the rotor of the magnetic levitation pump. The Hall sensor used is small in size, easy to install, and has a simple and compact overall structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a cross-sectional view of the placement of the Hall sensor on the magnetic levitation pump.

[0036] Figure 2 This is a top view of the placement of the Hall sensor on the magnetic levitation pump.

[0037] Figure 3 A second-order differential amplifier circuit for signal processing.

[0038] Figure 4 Schematic diagram of the geometric relationship when the rotor is tilted.

[0039] Figure 5 The figure is a flow chart of the method of the present invention.

[0040] In the figure: 1. rotor, 2. stator, 3. Hall sensor, 4. suspension winding, 5. drive winding. DETAILED DESCRIPTION

[0041] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The following is a specific implementation process.

[0042] like Figure 5 As shown, the present invention proposes a method for detecting the spatial posture of a magnetic levitation pump rotor, which specifically includes the following steps:

[0043] Step 1: Install two groups of Hall detection units on the inner wall of the stator teeth of the magnetic levitation pump. The two groups of Hall detection units are arranged vertically opposite to each other. The planes where the two groups of Hall detection units are located are parallel and spaced apart. The upper and lower planes are respectively denoted as A and B, that is, a Hall sensor in plane B is installed directly below each Hall sensor in plane A, and the line connecting the upper and lower Hall sensors is parallel to the Z axis; each group of Hall detection units includes four Hall sensors 3 arranged at equal intervals along the circumference, and the four Hall sensors form two pairs of orthogonally arranged Hall sensors. There are a total of 8 Hall sensors in the two groups of Hall detection units, and the structural models of the Hall sensors are the same;

[0044] Step 2: The rotor of the magnetic levitation pump is suspended and does not move, and the two sets of Hall detection units are subjected to baseline calibration;

[0045] Step 2 is as follows:

[0046] The rotor of the magnetic levitation pump is suspended and motionless. First, the N pole and S pole of the permanent magnet rotor are turned to the X-axis, and the Hall voltage signals of the two sets of Hall detection units corresponding to the X-axis in this state are obtained and used as the X-axis reference Hall voltage. Then, the N pole and S pole of the permanent magnet rotor are turned to the Y-axis, and the Hall voltage signals of the two sets of Hall detection units corresponding to the Y-axis in this state are obtained and used as the Y-axis reference Hall voltage. According to the X-axis reference Hall voltage and the Y-axis reference Hall voltage, the corresponding Hall sensor is benchmarked, that is, the calibrated constant coefficient k is obtained. c .

[0047] Step 3: After the calibration is completed, two sets of Hall detection units are used to collect Hall signals when the rotor rotates. The rotation angle of the rotor in the XY plane and the tilt angle of the rotor are calculated based on the two sets of Hall detection units, where the XY plane is a plane parallel to the plane where each set of Hall detection units is located.

[0048] Step 3 is as follows:

[0049] After the calibration is completed, the rotation angle of the rotor in the XY plane is calculated based on the Hall voltage signal collected by a group of Hall detection units close to the rotor plane;

[0050] And the tilt angle component of the rotor on the X-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the X-axis corresponding to the two groups of Hall detection units, and the tilt angle component of the rotor on the Y-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the Y-axis corresponding to the two groups of Hall detection units, and then the inclination angle of the rotor is calculated.

[0051] The rotation angle of the rotor in the XY plane is calculated based on the Hall voltage signal collected by a group of Hall detection units close to the rotor plane, specifically:

[0052] The Hall voltage signals collected by a group of Hall detection units close to the rotor plane are respectively the first X-axis Hall voltage U XA1 and the second X-axis Hall voltage U XA2 , the first Y-axis Hall voltage U YA1 and the second Y-axis Hall voltage U YA2 , for the first X-axis Hall voltage U XA1 and the second X-axis Hall voltage U XA2 After differential calculation, the relative Hall voltage U of the X-axis is obtained. X , for the first Y-axis Hall voltage U YA1 and the second Y-axis Hall voltage U YA2 After differential calculation, the Y-axis relative Hall voltage U is obtained. Y , the rotation angle of the rotor in the XY plane is calculated by the following formula

[0053]

[0054] The tilt angle component of the rotor on the X-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the X-axis corresponding to the two sets of Hall detection units, and the tilt angle component of the rotor on the Y-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the Y-axis corresponding to the two sets of Hall detection units, and then the tilt angle of the rotor is calculated, specifically:

[0055] S1: Collect the Hall signals of eight Hall sensors, recorded as U XA1 , U XA2 , U YA1 , U YA2 , U XB1 , U XB2 , U YB1 , U YB2 After performing differential calculation on the two X-axis Hall voltages collected by each group of Hall detection units, the corresponding X-axis relative Hall voltage U X , and then the X-axis relative Hall voltage U corresponding to the two sets of Hall detection units X After differential calculation, the X-axis Hall voltage signal difference ΔU caused by the rotor tilt is obtained X ;

[0056] S2: After performing differential calculation on the two Y-axis Hall voltages collected by each group of Hall detection units, the corresponding Y-axis relative Hall voltage U is obtained. Y , and then the Y-axis relative Hall voltage U corresponding to the two sets of Hall detection units Y After differential calculation, the Y-axis Hall voltage signal difference ΔU caused by the rotor tilt is obtained Y ;

[0057] According to the characteristics of the relatively arranged Hall sensors collecting signals, the actual X and Y direction voltage signals U of the rotor on plane A are X =k c |U XA1 -U XA2 |,U Y =k c |U YA1 -U YA2 |, where k c is the constant coefficient after calibration.

[0058] S3: Based on the X-axis Hall voltage signal difference ΔU generated by the rotor tilt X The difference ΔU between the Y-axis Hall voltage signal and the rotor tilt YThe axial displacement component Δz caused by the tilt in the X and Y directions is calculated by using the calibrated X-axis deviation-voltage relationship and Y-axis deviation-voltage relationship of the axial position when the rotor is tilted. X , Δz Y ; Among them, the calibrated axial position of the rotor when tilted is a linear relationship between the X-axis deviation and the Y-axis deviation and the voltage, satisfying the following relationship:

[0059] Δz X =k x ΔU X +b

[0060] Δz Y =k y ΔU Y +b

[0061] Among them, k x and k y are the X-axis fitting slope and the Y-axis fitting slope respectively, and b is the fitting intercept.

[0062] Therefore, the calibration of the above linear relationship can be completed through linear fitting.

[0063] S4: Figure 4 As shown, the rotor inclination angle θ is calculated using the following formula:

[0064]

[0065] Among them, θ X The tilt angle component of the rotor on the X-axis, θ Y is the tilt angle component generated on the Y axis, and d is the rotor diameter.

[0066] The present invention also proposes a device for detecting the spatial posture of the rotor of a magnetic suspension pump, and designs a double-order differential amplifier circuit. The entire detection device includes a Hall detection unit, a reference correction unit, a first differential amplifier circuit, a double-order differential amplifier circuit and a signal calculation circuit. Figure 1 and Figure 2 As shown, the magnetic levitation pump includes a rotor 1, a stator 2, a suspension winding 4 and a drive winding 5. Two groups of Hall detection units are installed on the inner wall of the stator teeth of the magnetic levitation pump. The two groups of Hall detection units are arranged vertically opposite to each other. The planes where the two groups of Hall detection units are located are parallel and spaced apart. The upper and lower planes are marked as A and B respectively; each group of Hall detection units includes four Hall sensors 3 arranged at equal intervals along the circumference, and the four Hall sensors form two pairs of orthogonally arranged Hall sensors. There are a total of 8 Hall sensors in the two groups of Hall detection units, and the structural models of the Hall sensors are the same;

[0067] A reference correction unit, used to correct each Hall detection unit according to a reference Hall voltage collected when the rotor 1 of the magnetic levitation pump is suspended and motionless;

[0068] A first differential amplifier circuit, used for performing differential operation on X-axis / Y-axis Hall voltage signals collected by a group of Hall detection units close to the rotor plane and sending corresponding operation results to the signal calculation circuit;

[0069] A dual-stage differential amplifier circuit, used for performing two differential operations on the Hall voltage signals collected by the two groups of Hall detection units and sending the corresponding operation results to the signal calculation circuit;

[0070] The signal calculation circuit is used to calculate the rotation angle of the rotor in the XY plane and the tilt angle of the rotor according to the differential operation sent by the first differential amplifier circuit and the dual-order differential amplifier circuit.

[0071] like Figure 3 As shown, the designed dual-stage differential amplifier circuit includes two first-stage differential amplifier circuits and one second-stage differential amplifier circuit, the two input ends of each first-stage differential amplifier circuit serve as the input ends of the dual-stage differential amplifier circuit, the output ends of the two first-stage differential amplifier circuits are respectively connected to the two input ends of the second-stage differential amplifier circuit, and the output end of the second-stage differential amplifier circuit serves as the output end of the dual-stage differential amplifier circuit.

[0072] The results of the two first-stage differential amplifier circuits are exactly the same as the resistance value. According to the characteristics of the differential amplifier circuit, the resistance value satisfies Assume that the signal at interface 1 of the operational amplifier is V1, the signal at interface 2 is V2, and the signal at interface 3 is V3, then the amplifier output signal The magnification is The structure of the second-stage differential amplifier circuit is similar. In order to reduce the influence of resistor accuracy and improve the common-mode rejection ratio, the amplification factor R'2 / R'1=10 is set to increase its gain. The Hall voltage signals U in the X and Y directions on the A plane and the B plane can be obtained through the first-order differential amplifier circuit. AX , U AY , U BX , U BY , will U AX and U BX , U AY and U BY The differential mode signal is amplified by the second-order differential amplifier circuit to obtain the X-axis and Y-axis variable voltage signals U generated by the rotor tilt. X ' X , U Y ′.

[0073] Finally, it should be noted that the above embodiments and explanations are only used to illustrate the technical solution of the present invention rather than to limit it. Those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope disclosed in the technical solution of the present invention, which should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for detecting the spatial posture of a magnetic levitation pump rotor, characterized in that: The following steps are involved: Step 1: Install two sets of Hall detection units on the inner side wall of the stator teeth of the magnetic levitation pump. The two sets of Hall detection units are arranged vertically opposite to each other, and the planes where the two sets of Hall detection units are located are parallel and spaced apart; each set of Hall detection units includes four Hall sensors arranged at equal intervals along the circumference; Step 2: The rotor of the magnetic levitation pump is suspended and does not move, and the two sets of Hall detection units are subjected to baseline calibration; Step 3: After the calibration is completed, two sets of Hall detection units are used to collect Hall signals when the rotor rotates. The rotation angle of the rotor in the XY plane and the tilt angle of the rotor are calculated based on the two sets of Hall detection units, where the XY plane is a plane parallel to the plane where each set of Hall detection units is located.

2. A method for detecting the spatial posture of a magnetic suspension pump rotor according to claim 1, characterized in that: The step 2 is specifically as follows: The rotor of the magnetic levitation pump is suspended and motionless. First, the N pole and S pole of the rotor are turned toward the X-axis, and the Hall voltage signals of the two groups of Hall detection units corresponding to the X-axis in this state are obtained and used as the X-axis reference Hall voltage. Then, the N pole and S pole of the rotor are turned toward the Y-axis, and the Hall voltage signals of the two groups of Hall detection units corresponding to the Y-axis in this state are obtained and used as the Y-axis reference Hall voltage. The corresponding Hall sensor is subjected to reference calibration according to the X-axis reference Hall voltage and the Y-axis reference Hall voltage.

3. The method for detecting the spatial posture of a magnetic suspension pump rotor according to claim 1, characterized in that: The step 3 is specifically as follows: After the calibration is completed, the rotation angle of the rotor in the XY plane is calculated based on the Hall voltage signal collected by a group of Hall detection units close to the rotor plane; And the tilt angle component of the rotor on the X-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the X-axis corresponding to the two groups of Hall detection units, and the tilt angle component of the rotor on the Y-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the Y-axis corresponding to the two groups of Hall detection units, and then the inclination angle of the rotor is calculated.

4. A method for detecting the spatial posture of a magnetic suspension pump rotor according to claim 3, characterized in that: The rotation angle of the rotor in the XY plane is calculated based on the Hall voltage signal collected by a group of Hall detection units close to the rotor plane, specifically: The Hall voltage signals collected by a group of Hall detection units close to the rotor plane are respectively the first X-axis Hall voltage U XA1 and the second X-axis Hall voltage U XA2 , the first Y-axis Hall voltage U YA1 and the second Y-axis Hall voltage U YA2 , for the first X-axis Hall voltage U XA1 and the second X-axis Hall voltage U XA2 After differential calculation, the relative Hall voltage U of the X-axis is obtained. X , for the first Y-axis Hall voltage U YA1 and the second Y-axis Hall voltage U YA2 After differential calculation, the Y-axis relative Hall voltage U is obtained. Y , the rotation angle of the rotor in the XY plane is calculated by the following formula 5. The method for detecting the spatial posture of a magnetic suspension pump rotor according to claim 3, characterized in that: The tilt angle component of the rotor on the X-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the X-axis corresponding to the two groups of Hall detection units, and the tilt angle component of the rotor on the Y-axis is calculated based on the Hall voltage signals collected by the Hall sensors on the Y-axis corresponding to the two groups of Hall detection units, and then the tilt angle of the rotor is calculated, specifically: S1: After performing differential calculation on the two X-axis Hall voltages collected by each group of Hall detection units, the corresponding X-axis relative Hall voltage U is obtained. X , and then the X-axis relative Hall voltage U corresponding to the two sets of Hall detection units X After differential calculation, the X-axis Hall voltage signal difference ΔU caused by the rotor tilt is obtained X ; S2: After performing differential calculation on the two Y-axis Hall voltages collected by each group of Hall detection units, the corresponding Y-axis relative Hall voltage U is obtained. Y , and then the Y-axis relative Hall voltage U corresponding to the two sets of Hall detection units Y After differential calculation, the Y-axis Hall voltage signal difference ΔU caused by the rotor tilt is obtained Y ; S3: Based on the X-axis Hall voltage signal difference ΔU generated by the rotor tilt X The difference ΔU between the Y-axis Hall voltage signal and the rotor tilt Y The axial displacement component Δz caused by the tilt in the X and Y directions is calculated by using the calibrated X-axis deviation-voltage relationship and Y-axis deviation-voltage relationship of the axial position when the rotor is tilted. X , Δz Y ; S4: Calculate the rotor inclination angle θ using the following formula: Among them, θ X The tilt angle component of the rotor on the X-axis, θ Y is the tilt angle component generated on the Y axis, and d is the rotor diameter.

6. A device for detecting the spatial posture of a magnetic suspension pump rotor, characterized in that: It includes a Hall detection unit, a reference correction unit, a first differential amplifier circuit, a dual-order differential amplifier circuit and a signal calculation circuit. Two groups of Hall detection units are installed on the inner side wall of the stator teeth of the magnetic levitation pump. The two groups of Hall detection units are arranged vertically opposite to each other. The planes where the two groups of Hall detection units are located are parallel and spaced apart. Each group of Hall detection units includes four Hall sensors arranged at equal intervals along the circumference. A reference correction unit, used to correct each Hall detection unit according to a reference Hall voltage collected when the rotor of the magnetic levitation pump is suspended and motionless; A first differential amplifier circuit, used for performing differential operation on X-axis / Y-axis Hall voltage signals collected by a group of Hall detection units close to the rotor plane and sending corresponding operation results to the signal calculation circuit; A dual-stage differential amplifier circuit, used for performing two differential operations on the Hall voltage signals collected by the two groups of Hall detection units and sending the corresponding operation results to the signal calculation circuit; The signal calculation circuit is used to calculate the rotation angle of the rotor in the XY plane and the tilt angle of the rotor according to the differential operation sent by the first differential amplifier circuit and the dual-order differential amplifier circuit.

7. A device for detecting the spatial posture of a magnetic suspension pump rotor according to claim 6, characterized in that: The dual-order differential amplifier circuit includes two first-stage differential amplifier circuits and one second-stage differential amplifier circuit, the two input ends of each first-stage differential amplifier circuit serve as the input ends of the dual-order differential amplifier circuit, the output ends of the two first-stage differential amplifier circuits are respectively connected to the two input ends of the second-stage differential amplifier circuit, and the output end of the second-stage differential amplifier circuit serves as the output end of the dual-order differential amplifier circuit.

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