Test system and method for loading and detecting motion magnetic field of magnetic bearing

Abstract

The invention provides a test system and method for loading and detecting a moving magnetic field of a magnetic bearing, and belongs to the technical field of permanent magnet equipment detection, aiming at the problem that a magnetic field detection instrument has a single detection mode and cannot simulate and test magnetic field distribution characteristics of the magnetic bearing under special working conditions such as axial deviation and radial eccentricity. A displacement loading device of the test system comprises an optical platform, a Z-axis lifting platform, a loading device X-axis movement mechanism, a loading device Y-axis movement mechanism, a T-shaped rotary table, a sample piece and a clamping mechanism, the time-varying magnetic field detection device comprises a support, a testing device Y-axis movement mechanism, a testing device Z-axis movement mechanism, a testing device X-axis movement mechanism, a connecting frame, an electric slip ring, a rotary table base, a testing device U-axis movement mechanism, a probe support and a probe mechanism. The method can effectively cover real-time magnetic field detection of various magnetic bearings (active, passive and hybrid magnetic bearings) under axial and radial offset.

Description

Technical Field

[0001] The present invention belongs to the technical field of magnetic field detection, and relates to a test system and method for magnetic field loading and detection of a magnetic bearing during movement. Background Art

[0002] In the process of modern industrial and technological development, bearings, as key elements for supporting rotating components and ensuring the smooth operation of machines, have always been the focus of research. Traditional mechanical contact bearings, with their mature technology and simple structure, once well met the requirements of most conventional industrial scenarios. However, nowadays, in many high-end fields such as aerospace and high-speed motors, the requirements for the performance of rotating machinery are becoming increasingly stringent. In this context, magnetic bearings, by virtue of their unique electromagnetic principle to achieve non-contact support for rotating components, have become components with great potential. It uses electromagnetic force to levitate and support the rotor. Compared with traditional mechanical bearings, it fundamentally eliminates mechanical contact, thereby avoiding problems related to friction, wear, and lubrication. However, in the above-mentioned key fields, magnetic bearings will be subjected to huge external pressures during operation. Therefore, it is required to have extremely excellent load-bearing capacity. The load-bearing capacity of a magnetic bearing is closely related to its own magnetic field strength.

[0003] Currently, in the field of magnetic bearing magnetic field testing, Hall probes are usually used to only test its static magnetic field, and it is impossible to test the magnetic field change under relative movement inside the magnetic bearing. Therefore, the present invention proposes a device and method for magnetic field loading and detection of a magnetic bearing during movement, so as to improve the time-varying magnetic field testing system of the magnetic bearing. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides a test system and method for magnetic field loading and detection of a magnetic bearing during movement to solve the problem that it is currently impossible to test the magnetic field change under relative movement inside the magnetic bearing. The test equipment provided by the present invention can realize the magnetic field testing of the magnetic bearing under different states (different rotor axial offsets and eccentricities), and further provide richer data support for magnetic bearing magnetic field analysis or finite element analysis verification.

[0005] To achieve the above content, the technical solution adopted by the present invention is as follows:

[0006] A test system for magnetic bearing moving magnetic field loading and detection, the test system includes a displacement loading device and a time-varying magnetic field detection device. The volume of the time-varying magnetic field detection device is relatively large compared to the displacement loading device, and it is arranged outside the test system. The probe mechanism 17 for detecting the magnetic field is located on this device, and the multi-degree-of-freedom movement of the probe mechanism 17 is achieved through the operation of various components. The displacement loading device serves as the support device for the magnetic bearing under test, located inside the test system, and moves inside the overall bracket 7 of the time-varying magnetic field detection device. The multi-degree-of-freedom movement of the magnetic bearing under test is achieved through the operation of various components, and it can simulate different working states (such as radial offset, axial offset) of the magnetic bearing under test while adjusting the position. Through the control of the displacement loading device and the time-varying magnetic field detection device on the magnetic bearing under test and the probe mechanism 17, the accurate determination of the position under different test conditions is realized. Specifically:

[0007] The first part: The displacement loading device includes an optical platform 1, a Z-axis lifting table 2, a loading device X-axis movement mechanism 3, a loading device Y-axis movement mechanism 4, a T-shaped turntable 5, and a clamping mechanism 6. The optical platform 1 serves as the base of the entire displacement loading device, carrying all the other components. The Z-axis lifting table 2 is located at the center of the upper surface of the optical platform 1. There are two groups of loading device X-axis movement mechanisms 3, which are respectively placed on both sides of the upper support plate of the Z-axis lifting table 2. Above the slider guides in the two groups of mechanisms, they are connected to the loading device Y-axis movement mechanism 4, jointly supporting the loading device Y-axis movement mechanism 4. The T-shaped turntable 5 is connected to the slider guide in the loading device Y-axis movement mechanism 4, and the magnetic bearing to be tested is placed on the upper end. The loading device X-axis movement mechanism 3, the loading device Y-axis movement mechanism 4, and the T-shaped turntable 5 serve as control mechanisms, and servo motors are equipped on them. The three work together to control the multi-degree-of-freedom movement of the magnetic bearing under test; the T-shaped turntable 5 serves as a support component, together with the clamping mechanism 6, for fixing the magnetic bearing under test. The following specifically introduces each component in the device, where:

[0008] The optical platform 1, on its upper surface, the Z-axis lifting table 2, the loading device X-axis movement mechanism 3, and the loading device Y-axis movement mechanism 4 are placed. The bottom surface is equipped with rollers to control the position of the magnetic bearing under test in the test system. However, since its position is controlled by the rollers below, the accuracy is relatively low.

[0009] The Z-axis lifting table 2 mainly includes eight groups of lifting table shafts and sleeves, two flat plates, and a lead screw. It is fixed on the optical platform 1 and moves with it. The tail end of the lead screw is connected to a servo motor. The movement of the magnetic bearing under test in the Z direction is achieved through the Z-axis lifting table 2. Specifically, the movement of the magnetic bearing under test in the Z direction is controlled through the control system.

[0010] The loading device X-axis motion mechanism 3 has two groups of loading device X-axis motion mechanisms 3 with the same structure, which are arranged on the left and right sides of the Z-axis lifting platform 2 respectively. Each group of loading device X-axis motion mechanism 3 includes a base plate, a square guide rail, a guide rail slider, a lead screw, a fixed end face of the lead screw and a servo motor; the bottom is threadedly connected and fixed to the Z-axis lifting platform 2 through the base plate, wherein the square guide rails and the fixed end faces of the lead screw on both sides are fixed to the base plate through threaded connection, the guide rail slider is connected to the top of the guide rail, and the top of the guide rail slider is connected to the loading device Y-axis motion mechanism 4, a lead screw is arranged in the middle part, and the two ends of the lead screw are respectively connected to the fixed end face and the servo motor, and the movement of the magnetic bearing to be measured in the X-axis direction is realized through the loading device X-axis motion mechanism 3, specifically, the lead screw is controlled by the servo motor to rotate and then drive the guide rail slider to move along the X-axis direction.

[0011] The Y-axis motion mechanism 4 of the loading device includes a base plate, a square guide rail, a guide rail slider, a lead screw, a fixed end face of the lead screw and a servo motor; the bottom is connected to the conductor sliders of the X-axis motion mechanism 3 of the loading device on both sides through the base plate, and the top is connected to the T-type turntable 5 through a threaded connection. The Y-axis motion mechanism 4 of the loading device realizes the movement of the measured magnetic bearing in the Y-axis direction. Specifically, the lead screw is controlled to rotate by the servo motor to drive the guide rail slider to move along the Y-axis direction.

[0012] The T-type turntable 5, as a support mechanism for the magnetic bearing to be tested, is connected to the Y-axis motion mechanism 4 of the loading device at the bottom, and the magnetic bearing to be tested is placed on the top. The movement of the optical platform 1, the Z-axis lifting platform 2, the X-axis motion mechanism 3 of the loading device, and the Y-axis motion mechanism 4 of the loading device are all indirectly driven to move the magnetic bearing to be tested through the T-type turntable 5. At the same time, a servo motor is built into the T-type turntable 5, and the servo motor drives the T-type turntable 5 to rotate, that is, indirectly drives the rotor to move, so that the magnetic bearing to be tested can rotate around the Z axis.

[0013] The clamping mechanism 6 uses a triangular fixture as the workpiece, and its main function is to fix the external stator of the magnetic bearing to be tested. By cooperating with the Z-axis lifting platform 2, the loading device X-axis motion mechanism 3, and the loading device Y-axis motion mechanism 4, various test conditions of the magnetic bearing to be tested are simulated, including the axial relative displacement of the stator and rotor, and the radial offset and axial offset of the rotor.

[0014] Second part: The time-varying magnetic field detection device includes a bracket 7, a cabinet 8, a test device Y-axis movement mechanism 9, a test device Z-axis movement mechanism 10, a test device X-axis movement mechanism 11, a connecting frame 12, a slip ring 13, a turntable base 14, a test device U-axis movement mechanism 15, a probe bracket 16, and a probe mechanism 17. The bracket 7 serves as the base of the time-varying magnetic field detection device and is located at the bottom end. The other mechanisms are all arranged above the bracket 7. The bracket 7 is composed of three vertically arranged frame plate-like structures, enclosing a square structure with an opening on one side and an opening at the top. The displacement loading device is fixed at the center position inside the square structure. There are two sets of the test device Y-axis movement mechanisms 9, symmetrically installed on the tops of two frame plate-like structures of the bracket 7; there are two sets of the test device Z-axis movement mechanisms 10, symmetrically installed on the test device Y-axis movement mechanisms 9; there is one set of the test device X-axis movement mechanisms 11, installed between the two test device Z-axis movement mechanisms 10, and the connecting frame 12 is installed on the test device X-axis movement mechanisms 11; through the connecting frame 12, it is connected to the slip ring 13, the turntable base 14, and the test device U-axis movement mechanism 15. The test device U-axis movement mechanism 15 is connected to the probe mechanism 17 through the probe bracket 16. Each movement mechanism (including the test device Y-axis movement mechanism 9, the test device Z-axis movement mechanism 10, the test device X-axis movement mechanism 11, and the test device U-axis movement mechanism 15) internally has a servo motor. By working together, it realizes the free movement of the probe mechanism 17 in the three-dimensional space of the time-varying magnetic field detection device. The movement of each movement mechanism in different directions is transmitted to the probe mechanism 17 through this probe bracket 16 to achieve precise control of its position. The following specifically introduces each component in the device, among which: The cabinet 8 includes a control mechanism, a computer, and a gaussmeter, which realizes the control of the servo motors of the entire test system and collects and processes the information collected in the experiment.

[0015] The bracket 7, as the base of the time-varying magnetic field detection device, is fixed to the bottom plate of the test device Y-axis movement mechanism 9 through threaded connection above, playing a supporting role.

[0016] The test device Y-axis movement mechanism 9: There are two sets of the test device Y-axis movement mechanisms 9 with the same structure, respectively placed on both sides of the bracket 7. Its structure and working principle are similar to those of the loading device X-axis movement mechanism 3, and both are composed of a bottom plate, a square guide rail, a guide rail slider, a lead screw, the fixed end face of the lead screw, and a servo motor, only with different part parameters. The movement of the test device along the Y-axis is realized by controlling the servo motor through the control system.

[0017] The Z-axis motion mechanism 10 of the test device consists of two sets of Z-axis motion mechanisms 10 with the same structure, which are arranged on the Y-axis motion mechanism 9 of the test device. Each set of the Z-axis motion mechanism 10 of the test device is composed of four guide columns, four guide column cantilever beams, one lead screw and a servo motor. Among them, the servo motor is connected above the guide column, and the lower part is fixed to the guide rail slider in the Y-axis motion mechanism 9 of the test device through threaded connection. The two ends of the lead screw are respectively connected to the servo motor and the guide column bottom plate, and the middle part is connected to the four guide column cantilever beams. The tester controls the servo motor through the control system to control the movement of the test device along the Z-axis direction.

[0018] The X-axis motion mechanism 11 of the test device has the same structure and working principle as the Y-axis motion mechanism 9 of the test device, only with slightly different relevant parameters. Its lower bottom plate is connected to the cantilever beams at both ends of the Z-axis motion mechanism 10 of the test device, and the right end is connected to the servo motor. Through the control of the control system, the movement of the test device along the X-axis direction is realized.

[0019] The connecting frame 12 mainly plays a role of connection and support. The upper part is fixed to the guide rail slider of the X-axis motion mechanism 11 of the test device through threaded connection, and the upper surface of the bottom layer is connected to the turntable base, transmitting the motion in all directions to the probe mechanism 17.

[0020] The electric slip ring 13 is fixed above the turntable base 14. It is a device used to transmit electricity and signals during rotation. Its function is to transmit control signals to the rotating mechanism and send back the test data signals to the computer for subsequent analysis.

[0021] The turntable base 14 has the electric slip ring placed on its top, and the lower end is fixed to the bottom plate in the U-axis motion mechanism 15 of the test device through threaded connection. It is equipped with a servo motor. Through the control of the control system, it drives the electric slip ring and related mechanisms to realize the rotation of the test device along the Z-axis.

[0022] The U-axis motion mechanism 15 of the test device is composed of a bottom plate, a square guide rail, a guide rail slider, a protruding arm, a lead screw, the fixed end face of the lead screw and a servo motor. The bottom of its top is connected to the turntable base 14 and rotates with it. Its protruding arm is located at the bottom end of the mechanism and is connected to the guide rail slider of this mechanism. The front end of the protruding arm is connected to the probe bracket 17, and the probe mechanism 17 is precisely moved on the guide rail through the control of the servo motor.

[0023] The probe holder 16 includes a pitch probe holder and a yaw probe holder. The upper part of the pitch probe holder is connected to the extension arm of the U-axis motion mechanism 15 of the testing device. The pitch motion of the pitch probe holder can be adjusted by the fine-tuning screws on the probe holder 16. The yaw probe holder is located at the bottom and is connected to the probe mechanism 17. Similarly, the yaw motion of the yaw probe holder can be adjusted by the fine-tuning screws on the yaw probe holder. The two probe holders are adjusted together to make the probe mechanism 17 parallel to the measured magnetic bearing, so as to test the magnetic field intensity change and distribution under different conditions.

[0024] The probe mechanism 17, as the most important part of the testing device, is composed of a carbon fiber connecting rod, a probe fixture, and a Hall probe. Among them, the upper carbon fiber connecting rod is connected to the yaw probe holder of the probe holder 16; there are two groups of probe fixtures. The upper part is connected to the carbon fiber connecting rod, and the lower part fixes the Hall probe through the combined action of the two probes; through the control of each mechanism of the testing device (including the Y-axis motion mechanism 9, the Z-axis motion mechanism 10, the X-axis motion mechanism 11, and the turntable base 14) of the testing device, the Hall probe can realize the movement in six degrees of freedom directions. Based on the Hall effect principle, the Hall probe measures the magnetic field intensity at the placed position.

[0025] A testing method for magnetic bearing motion magnetic field loading and detection, realized based on the above testing system, includes the following steps:

[0026] The first step is to place the magnetic bearing to be measured above the T-shaped turntable 5 and fix it with the triangular fixture contained in the fixture mechanism 6.

[0027] The second step is to control the time-varying magnetic field detection device and place the detection part of the Hall probe at the part to be detected of the magnetic bearing. Specifically:

[0028] Step 2.1, manually control the optical platform 1 and control its position at an appropriate position inside the bracket 7 in the time-varying magnetic field detection device.

[0029] Step 2.2, control the servo motors on the Y-axis motion mechanism 9, the Z-axis motion mechanism 10, the X-axis motion mechanism 11, and the turntable base 14 of the testing device, so that the guide rail sliders on each motion mechanism move precisely in the X direction, Y direction, and Z direction and rotate precisely along the Z axis, indirectly realizing the precise movement of the Hall probe in the three-dimensional space of the entire testing system in the probe mechanism 17, and making the Hall probe accurately reach the position to be measured.

[0030] The third step is to control the displacement loading device to simulate different states (different axial offsets and radial offsets) of the magnetic bearing to be measured. During displacement loading, the Hall probe can detect its magnetic field change in real time.

[0031] Step 3.1, control the servo motors on the X-axis motion mechanism 4, Y-axis motion mechanism 3, Z-axis lifting table 2 and T-shaped turntable 5 of the loading device, so that the guide rail sliders on each motion mechanism move precisely in the X, Y, and Z directions and rotate precisely along the Z-axis, indirectly driving the rotor of the magnetic bearing to be tested to move in all directions, thereby simulating different states required for the magnetic bearing test.

[0032] Step 3.2, during the movement of the magnetic bearing to be tested under different working conditions, the real-time data signal is transmitted to the computer through the electric slip ring and is processed and analyzed by the tester.

[0033] The beneficial effects of the present invention are as follows:

[0034] Aiming at the single detection method of the magnetic field detection instrument, which cannot simulate and test the magnetic field distribution characteristics of the magnetic bearing under special working conditions such as axial offset and radial eccentricity, the present invention proposes a method for loading and detecting the moving magnetic field of the magnetic bearing. This method can effectively cover the real-time detection of the magnetic field of various magnetic bearings (active, passive, and hybrid magnetic bearings) under axial and radial offsets. Description of the Drawings

[0035] Figure 1 It is a schematic diagram of the overall structure of the permanent magnet equipment spatial displacement loading and time-varying magnetic field detection device;

[0036] Figure 2 It is the front view of the overall structure of the permanent magnet equipment spatial displacement loading and time-varying magnetic field detection device;

[0037] Figure 3 It is the top view of the overall structure of the permanent magnet equipment spatial displacement loading and time-varying magnetic field detection device;

[0038] Figure 4 It is a schematic diagram of the overall structure of the permanent magnet equipment spatial displacement loading device;

[0039] Figure 5 It is a schematic diagram of the overall structure of the permanent magnet equipment time-varying magnetic field detection device;

[0040] In the figure: 1 optical platform; 2 Z-axis lifting table; 3 loading device X-axis motion mechanism; 4 loading device Y-axis motion mechanism; 5 T-shaped turntable; 6 clamping mechanism; 7 bracket; 8 cabinet; 9 test device Y-axis motion mechanism; 10 test device Z-axis motion mechanism; 11 test device X-axis motion mechanism; 12 connecting frame; 13 electric slip ring; 14 turntable base; 15 test device U-axis motion mechanism; 16 probe bracket; 17 probe mechanism. Detailed Embodiment

[0041] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that for the convenience of description, only the parts related to the present invention rather than all the structures are shown in the drawings.

[0042] As shown in the attached Figure 1 , a test system for magnetic bearing moving magnetic field loading and detection, the displacement loading device includes an optical platform 1, a Z-axis lifting table 2, a loading device X-axis moving mechanism 3, a loading device Y-axis moving mechanism 4, a T-shaped turntable 5, and a clamping mechanism 6. The time-varying magnetic field detection device includes a bracket 7, a cabinet 8, a test device Y-axis moving mechanism 9, a test device Z-axis moving mechanism 10, a test device X-axis moving mechanism 11, a connecting frame 12, a slip ring 13, a turntable base 14, a test device U-axis moving mechanism 15, a probe bracket 16, and a probe mechanism 17.

[0043] As shown in the attached Figure 2 , the main view of the overall structure of the magnetic bearing displacement loading and time-varying magnetic field detection device is shown. All the other assembled parts are the same as those shown in the attached Figure 1 figure.

[0044] As shown in the attached Figure 3 , the top view of the overall structure of the magnetic bearing displacement loading and time-varying magnetic field detection device is shown. All the other assembled parts are the same as those shown in the attached Figure 1 figure.

[0045] As shown in the attached Figure 4 , a part of the displacement loading device in a test system for magnetic bearing moving magnetic field loading and detection, includes an optical platform 1, a Z-axis lifting table 2, a loading device X-axis moving mechanism 3, a loading device Y-axis moving mechanism 4, a T-shaped turntable 5, and a sample and clamping mechanism 6.

[0046] For example, for a certain processed magnetic bearing, it is necessary to measure the magnetic field strength changes under different conditions (such as the axial relative displacement between the stator and rotor, eccentricity) to determine the influence of the axial displacement amount and eccentricity on the magnetic field of the magnetic bearing. The specific operations include:

[0047] Place the magnetic bearing sample 6 to be measured above the T-shaped turntable 5. The stator of the sample is fixed by the clamping mechanism, and the rotor is connected to the T-shaped turntable 5. The diameter of the tabletop of the T-shaped turntable 5 is 400 mm, and it can bear a weight of 120 kg. It is equipped with a Japanese Yaskawa servo motor drive and can be controlled by a four-axis servo motor controller to realize the rotational movement of the magnetic bearing on the U axis. In the present invention, at different calibration angles of the T-shaped turntable 5, the absolute value of the error is within 9″, the positioning accuracy is 0.010°, and the resolution is 0.001°, which can ensure the precise movement of the tested magnetic bearing in the U degree of freedom direction.

[0048] At the bottom of the displacement loading device is the optical table 1. All other components of the displacement loading device are placed above it, and rollers are configured below. The material is selected as non-magnetic medical 304 steel. The platform parameters are 3000mm×2500mm×400mm. The operator can preliminarily adjust the positions of the X-axis and Y-axis of the permanent magnet bearing by moving the optical table 1, but the position accuracy is relatively low.

[0049] Further, above the optical table 1 is the Z-axis lifting table 2 in the displacement loading device. It adopts a widened load-bearing structure, mainly including 8 sets of lifting table shafts and bushings, two flat plates, and a lead screw, which is fixed on the optical table and moves with it. The end of the lead screw is connected to a Yaskawa servo motor in Japan, and the movement of the permanent magnet bearing in the Z direction is controlled by a four-dimensional servo motor controller. In the present invention, when the Z-axis lifting table 2 has different calibration lengths within 300mm, the absolute value of the error is within the range of 10μm, its positioning accuracy is 0.018mm, and the resolution is 0.001mm, which can ensure the accurate movement of the tested magnetic bearing in the Z-degree-of-freedom direction.

[0050] In this embodiment, above the Z-axis lifting table 2 is the X-axis moving mechanism 3 in the displacement loading device. There are two sets of loading device X-axis moving mechanisms 3 with the same structure, which are respectively arranged on the left and right sides of the Z-axis lifting table 2. Each set of loading device X-axis moving mechanism 3 includes a bottom plate, a square guide rail, a guide rail slider, a lead screw, the fixed end face of the lead screw, and a servo motor; the lower part is fixedly connected to the Z-axis lifting table 2 through the bottom plate by thread. The square guide rails on both sides and the fixed end face of the lead screw are fixedly connected to the bottom plate by thread. The distance between the two ends of the guide rail is 465mm, and the width of the guide rail slider connected above the guide rail is 165mm. Therefore, the actual movable distance of this mechanism in the X direction is 300mm. The upper part of the slider is connected to the Y-axis moving mechanism 4, and the lead screw is connected in the middle. The two ends of the lead screw are respectively connected to the fixed end face and a Yaskawa servo motor in Japan. The axis height of the fixed end face is 30mm. By controlling the four-dimensional servo motor controller, the lead screw can be rotated to drive the moving slider to move along the X-axis direction. In the present invention, when the X-axis moving mechanism 3 has different calibration lengths within 300mm, the absolute value of the error is within the range of 3μm, its positioning accuracy is 0.018mm, and the resolution is 0.001mm, which can ensure the accurate movement of the tested magnetic bearing in the X-degree-of-freedom direction.

[0051] In this embodiment, above the X-axis motion mechanism 3 is the Y-axis motion mechanism 4 in the displacement loading device. The structure includes a base plate, square guide rails, guide rail sliders, lead screws, fixed end faces of the lead screws, and servo motors. The bottom is connected to the conductor sliders of the X-axis motion mechanisms 3 of the two-side loading devices through the base plate, and the upper part is connected to the T-shaped turntable 5 through threaded connection. The distance between the two ends of the guide rails is 465 mm, and the guide rail sliders are connected above the guide rails. The width of the sliders is 165 mm, that is, the actual movable distance of this mechanism is 300 mm. Specifically, the servo motor is used to control the rotation of the lead screw to drive the guide rail slider to move along the Y-axis direction. In the present invention, within different calibration lengths within 300 mm of the Y-axis motion mechanism 3, the absolute value of the error is within the range of 3 μm, its positioning accuracy is 0.018 mm, and the resolution is 0.001 mm, which can ensure the precise movement of the tested magnetic bearing in the Y-degree-of-freedom direction.

[0052] Through the different mechanisms in the above displacement loading device, the control of the rotor of the tested magnetic bearing in the 4-degree-of-freedom direction can be achieved. And since the stator of the magnetic bearing is fixed by the clamping mechanism, therefore, the simulation of the magnetic bearing in different states (such as the axial relative displacement and eccentricity of the stator and rotor) can be completed through the above method.

[0053] As shown in the appendix Figure 5 , a part of the time-varying magnetic field detection device in a test system for magnetic bearing motion magnetic field loading and detection includes a support 7, a cabinet 8, a test device Y-axis motion mechanism 9, a test device Z-axis motion mechanism 10, a test device X-axis motion mechanism 11, a connecting frame 12, a slip ring 13, a turntable base 14, a test device U-axis motion mechanism 15, a probe support 16, and a probe carrier 17.

[0054] The above has given specific examples and discussed the specific working principle of the displacement loading device. The following will explain the working process and principle of the magnetic field detection device, including:

[0055] The lowermost end of the entire device is the support 7, which serves as the base of the test device. The upper part is fixed to the base plate of the test device Y-axis motion mechanism through threaded connection, playing a supporting role for the test device. Its structural dimensions are greater than 2000 mm × 2000 mm × 2000 mm, and the loading device moves within this range.

[0056] In this embodiment, beside the bracket 7 is the cabinet 8 of the time-varying magnetic field detection device, with dimensions of 1000mm×800mm×600mm. A control mechanism, a computer, and a gaussmeter are placed above it. Among them, the three-dimensional gaussmeter model is CH-600, with a VGA color 6-bit resolution, a resolution of 0.0001mT, a DC accuracy of ±0.10% of the reading (0 - 2T), an AC accuracy of ±1.0% of the reading (0 - 30T), and a frequency response range of 0 - 50KHz. The laptop computer uses an i5 processor and a 15.6-inch display screen. The computer is configured with F-30 system software (a multi-dimensional magnetic field measurement system software with functions such as motion control, data acquisition, data analysis, and drawing), which can achieve the motion control of the servo motor and perform relevant processing on the information collected by the gaussmeter.

[0057] In this embodiment, above the bracket 7 is the Y-axis motion mechanism 9 of the time-varying magnetic field detection device. There are two sets of test device Y-axis motion mechanisms 9 with the same structure, which are respectively placed on both sides of the bracket 7. Its structure and working principle are similar to those of the loading device X-axis motion mechanism, and both are composed of a bottom plate, a square guide rail, a guide rail slider, a lead screw, the fixed end face of the lead screw, and a servo motor, only with different part parameters. Its stroke is 2000mm. The two end motion mechanisms achieve the movement of the test device along the Y-axis through the control of the servo motor by a five-axis servo motor controller. In this invention, within different calibration lengths within 2000mm, the absolute value of the error of the Y-axis motion mechanism 9 is within 15μm, its positioning accuracy is 0.025mm, and its resolution is 0.001mm, which can ensure the precise movement of the Hall probe carried on the device in the Y-degree-of-freedom direction.

[0058] In this embodiment, above the Y-axis motion mechanism 9 is the Z-axis motion mechanism 10 of the time-varying magnetic field detection device. There are two sets of test device Z-axis motion mechanisms 10 with the same structure, which are arranged on the test device Y-axis motion mechanism 9. Each set of test device Z-axis motion mechanism 10 is composed of four guide posts, four guide post cantilever beams, one lead screw, and a servo motor. Among them, the servo motor is connected above the guide post, and the lower part is fixed to the guide rail slider in the test device Y-axis motion mechanism 9 through threaded connection. The two ends of the lead screw are respectively connected to the servo motor and the guide post bottom plate, and the middle part is connected to the four guide post cantilever beams. Its stroke is 2000mm. The experimenter can control the servo motor through a five-axis servo motor controller to manipulate the test device to move along the Z-axis direction. In this invention, within different calibration lengths within 2000mm, the absolute value of the error of the Z-axis motion mechanism 10 is within 10μm, its positioning accuracy is 0.025mm, and its resolution is 0.001mm, which can ensure the precise movement of the Hall probe carried on the device in the Z-degree-of-freedom direction.

[0059] In this embodiment, above the Z-axis motion mechanism 10 is the X-axis motion mechanism 11 in the time-varying magnetic field detection device. Its structure and working principle are the same as those of the Y-axis motion mechanism 9 of the test device, except that the relevant parameters are slightly different. The bottom plate below it is connected to the cantilever beams at both ends of the Z-axis motion mechanism 10 of the test device. The right end is connected to a Yaskawa servo motor in Japan and is controlled by a five-axis servo motor controller to realize the movement of the test device in the X-axis direction. Its stroke is 2000 mm. In the present invention, within different calibration lengths within 2000 mm of the X-axis motion mechanism 11, the absolute value of its error is within the range of 6 μm, its positioning accuracy is 0.025 mm, and its resolution is 0.001 mm, which can ensure the precise movement of the Hall probe mounted on the device in the X-degree-of-freedom direction.

[0060] In this embodiment, connected to the X-axis motion mechanism 11 is the connecting frame 12 in the time-varying magnetic field detection device, which mainly plays a role of connection and support. The upper part is fixed to the guide rail slider of the X-axis motion mechanism 11 of the test device by threaded connection, and the upper surface of the bottom layer is connected to the turntable base, transmitting the motion in all directions to the probe mechanism 17.

[0061] In this embodiment, connected to the connecting frame 12 are the electric slip ring 13 and the turntable base 14 in the time-varying magnetic field detection device. Among them,

[0062] The electric slip ring 13 is connected to the turntable base 14 and is a device used to transmit electric power and signals during rotation. Its function is to transmit control signals to the rotating mechanism and transmit the test data signals back to the computer for subsequent analysis. The lower end of the turntable base 14 is fixed to the bottom plate in the U-axis motion mechanism 15 of the test device by threaded connection. The tabletop diameter is 200 mm, and it can bear a weight of 60 kg. It is equipped with a Yaskawa servo motor in Japan and is controlled by a five-axis servo motor controller to drive the electric slip ring and related mechanisms to realize the rotation of the test device around the U axis. Its stroke is 360°. In the present invention, within different calibration angles of the turntable base 14, the absolute value of its error is within the range of 9″, its positioning accuracy is 0.010°, and its resolution is 0.001°, which can ensure the precise movement of the Hall probe mounted on the test device in the U-degree-of-freedom direction.

[0063] In this embodiment, below the turntable base 14 is the U-axis motion mechanism 15 of the time-varying magnetic field detection device. The structure consists of a base plate, square guide rails, guide rail sliders, a protruding arm, a lead screw, the fixed end face of the lead screw, and a servo motor. The bottom of its top is connected to the turntable base 14 and rotates with it. Its protruding arm is located at the bottom end of the mechanism and is connected to the guide rail slider of this mechanism. The front end of the protruding arm is connected to the probe support 17. The servo motor is controlled by a five-axis servo motor controller to control the movement of the test device in the Y direction. Its stroke is 1000 mm. In the present invention, within different calibration lengths within 1000 mm of the U-axis motion mechanism 15, the absolute value of its error is within the range of 2 μm, its positioning accuracy is 0.010 mm, and its resolution is 0.001 mm, which can ensure the precise movement of the Hall probe carried on the device in the Y degree of freedom direction. And because the stroke is less than that of the Y-axis motion mechanism 9, by adjusting the Y direction of the time-varying magnetic field detection device simultaneously with the two mechanisms, the position of the Hall probe can be made more accurate.

[0064] In this embodiment, below the U-axis motion mechanism 15 of the detection device is connected to the probe support 16 of the time-varying magnetic field detection device. The probe support 16 is divided into two parts, namely the pitching probe support and the yaw probe support. The pitching probe support is connected above to the protruding arm of the U-axis motion mechanism 15 of the test device, and the pitching probe support can perform pitching motion by adjusting the fine-tuning screws on the probe support 16. The yaw probe support is located at the bottom and is connected to the probe mechanism 17. Similarly, the yaw probe support can perform yaw motion by adjusting the fine-tuning screws on the yaw probe support. The two probe supports are adjusted together to make the Hall probe parallel to the magnetic bearing to test the change and distribution of the magnetic field strength of the workpiece under test in different states.

[0065] Finally, below the probe support 16 is connected to the probe mechanism 17, which is the most important part of the test device and consists of a carbon fiber connecting rod, a probe fixture, and a Hall probe. Among them, the upper carbon fiber connecting rod is connected to the yaw probe support of the probe support 16; there are two groups of probe fixtures. The upper part is connected to the carbon fiber connecting rod, and the lower part fixes the Hall probe through the combined action of the two probes; through the control of each mechanism of the test device (including the Y-axis motion mechanism 9, the Z-axis motion mechanism 10, the X-axis motion mechanism 11, and the turntable base 14) of the test device, the Hall probe can achieve motion in six degrees of freedom. Based on the Hall effect principle, the Hall probe tests the magnetic field strength at the placed position. Among them, the probe of this time-varying magnetic field detection device uses a high-precision three-axis probe, model 3AHD802FG, with a metal handle, using the CHHALL metal laser process. Its probe side length is 3 mm, its length is 1500 mm, and its accuracy is ±0.10% of the reading, which can be applicable to the test of the change in magnetic field strength of magnetic bearings of various sizes.

[0066] The above are only specific embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A test system for loading and detecting magnetic field of magnetic bearing motion, characterized in that: The test system comprises a displacement loading device and a time-varying magnetic field detection device, wherein the time-varying magnetic field detection device is arranged outside the test system, and the displacement loading device is located inside the test system as a support device for the magnetic bearing to be tested; the displacement loading device and the time-varying magnetic field detection device control the magnetic bearing to be tested and the probe mechanism (17), thereby realizing accurate determination of the position under different test conditions; specifically: The displacement loading device comprises an optical platform (1), a Z-axis lifting platform (2), an X-axis motion mechanism (3) of a loading device, a Y-axis motion mechanism (4) of a loading device, a T-type turntable (5), and a clamping mechanism (6); the optical platform (1) is the base of the entire displacement loading device, and the Z-axis lifting platform (2) is located on the optical platform (1); two groups of X-axis motion mechanisms (3) of the loading device are respectively placed on both sides of the upper support plate of the Z-axis lifting platform (2); the upper parts of the slider guide rails in the two groups of X-axis motion mechanisms (3) of the loading device are connected to the Y-axis motion mechanism (4) of the loading device; the T-type turntable (5) is connected to the slider guide rail in the Y-axis motion mechanism (4) of the loading device; the T-type turntable (5) and the clamping mechanism (6) are used to fix the magnetic bearing to be measured; the X-axis motion mechanism (3) of the loading device, the Y-axis motion mechanism (4) of the loading device, and the T-type turntable (5) serve as control mechanisms, and are equipped with servo motors to control the multi-degree-of-freedom motion of the magnetic bearing to be measured; The time-varying magnetic field detection device comprises a bracket (7), a Y-axis motion mechanism (9) of a test device, a Z-axis motion mechanism (10) of a test device, an X-axis motion mechanism (11) of a test device, a connecting frame (12), an electric slip ring (13), a turntable base (14), a U-axis motion mechanism (15) of a test device, a probe bracket (16), and a probe mechanism (17); the bracket (7) serves as a base of the time-varying magnetic field detection device and is located at the bottom, and the remaining mechanisms are arranged above the bracket (7); the bracket (7) is composed of three vertically arranged frame plate structures, which form a square structure, and the displacement loading device is fixed inside the square structure; two groups of Y-axis motion mechanisms (9) of the test device are symmetrically installed on the top of the bracket (7); two groups of Z-axis motion mechanisms (10) of the test device are symmetrically installed The invention is installed on a Y-axis motion mechanism (9) of a test device; a group of X-axis motion mechanisms (11) of a test device is installed between two Z-axis motion mechanisms (10) of the test device; a connecting frame (12) is installed on the X-axis motion mechanism (11) of the test device; the connecting frame (12) is connected to an electric slip ring (13), a turntable base (14), and a U-axis motion mechanism (15) of the test device; the U-axis motion mechanism (15) of the test device is connected to a probe mechanism (17) through a probe bracket (16); each motion mechanism is built with a servo motor to realize the free movement of the probe mechanism (17) in the three-dimensional space of the time-varying magnetic field detection device; the movement of each motion mechanism in different directions is transmitted to the probe mechanism (17) through the probe bracket (16) to realize accurate position control.

2. A test system for loading and detecting magnetic field of magnetic bearing motion according to claim 1, characterized in that: The bottom surface of the optical platform (1) is provided with a roller to control the position of the magnetic bearing to be tested in the test system.

3. A test system for loading and detecting magnetic field of magnetic bearing motion according to claim 1, characterized in that: In the displacement loading device: The loading device X-axis motion mechanism (3) has two groups with the same structure, both comprising a base plate, a square guide rail, a guide rail slider, a lead screw, a fixed end face of the lead screw and a servo motor; the base plate is fixed to the Z-axis lifting platform (2), wherein the square guide rails on both sides and the fixed end face of the lead screw are fixed to the base plate, the upper part of the guide rail is connected to the guide rail slider, the upper part of the guide rail slider is connected to the loading device Y-axis motion mechanism (4), the middle part is arranged with a lead screw, and the two ends of the lead screw are respectively connected to the fixed end face and the servo motor; the movement of the magnetic bearing to be measured in the X-axis direction is realized; The Y-axis motion mechanism (4) of the loading device comprises a bottom plate, a square guide rail, a guide rail slider, a lead screw, a fixed end surface of the lead screw and a servo motor; the bottom is connected to the conductor sliders of the X-axis motion mechanism (3) of the loading device on both sides through the bottom plate, and the top is connected to the T-type turntable (5) through a threaded connection; the motion of the magnetic bearing to be tested in the Y-axis direction is realized; The testing device Y-axis motion mechanism (9) has two groups with the same structure. The structure is the same as the loading device X-axis motion mechanism (3), and is also composed of a base plate, a square guide rail, a guide rail slider, a lead screw, a fixed end face of the lead screw and a servo motor, but the parameters of the parts are different; the testing device is moved along the Y-axis; The test device Z-axis motion mechanism (10) has two groups with the same structure; both groups are composed of four guide posts, four guide post cantilever beams, a lead screw and a servo motor, wherein the guide posts are connected to the servo motor at the top and fixed to the guide rail slider in the test device Y-axis motion mechanism (9) at the bottom, the two ends of the lead screw are respectively connected to the servo motor and the guide post bottom plate, and the middle part is connected to the four guide post cantilever beams, so as to realize the movement of the test device along the Z-axis direction; The structure and working principle of the X-axis motion mechanism (11) of the testing device are the same as those of the Y-axis motion mechanism (9) of the testing device. The bottom plate below the X-axis motion mechanism (11) is connected to the cantilever beams at both ends of the Z-axis motion mechanism (10) of the testing device, and the right end is connected to a servo motor to realize the movement of the testing device along the X-axis direction.

4. A test system for loading and detecting magnetic field of magnetic bearing motion according to claim 1, characterized in that: The T-shaped turntable (5) serves as a support mechanism for the magnetic bearing to be measured. The bottom is connected to the Y-axis motion mechanism (4) of the loading device, and the magnetic bearing to be measured is placed on the top. The movement of the optical platform (1), the Z-axis lifting platform (2), the X-axis motion mechanism (3) of the loading device, and the Y-axis motion mechanism (4) of the loading device all indirectly drives the movement of the magnetic bearing to be measured through the T-shaped turntable (5). At the same time, a servo motor is built in the T-shaped turntable (5), and the T-shaped turntable (5) is driven to rotate by the servo motor, so that the magnetic bearing to be measured can rotate around the Z axis.

5. A test system for loading and detecting magnetic field of magnetic bearing motion according to claim 1, characterized in that: In the time-varying magnetic field detection device: The connecting frame (12) is connected to the guide rail slider of the X-axis motion mechanism (11) of the test device at the top, and is connected to the turntable base (14) at the bottom, so as to transmit the motion in each direction to the probe mechanism (17); An electric slip ring (13) is placed on the top of the turntable base (14), and the lower end is connected to the bottom plate in the U-axis motion mechanism (15) of the test device. The turntable base (14) is provided with a servo motor, which drives the electric slip ring and related mechanisms to realize the rotation of the test device along the Z axis through the control of the control system.

6. A test system for loading and detecting magnetic field of a magnetic bearing according to claim 1, characterized in that: The electric slip ring (13) is fixed above the turntable base (14) and is a device used to transmit power and signals during the rotation process.

7. A test system for loading and detecting magnetic field of magnetic bearing motion according to claim 1, characterized in that: The U-axis motion mechanism (15) of the testing device is composed of a bottom plate, a square guide rail, a guide rail slider, an extension arm, a lead screw, a fixed end face of the lead screw and a servo motor. The bottom of the top is connected to the turntable base (14) and rotates with it. The extension arm is located at the bottom end of the mechanism and is connected to the guide rail slider of the mechanism. The front end of the extension arm is connected to the probe bracket 17. The probe mechanism (17) is precisely moved on the guide rail by controlling the servo motor.

8. A test system for magnetic bearing motion magnetic field loading and detection according to claim 1, characterized in that: The probe bracket (16) comprises a pitch probe bracket and a yaw probe bracket; the pitch probe bracket is connected to the extension arm of the U-axis motion mechanism (15) of the test device at the top, and the yaw probe bracket is located at the bottom and connected to the probe mechanism (17); the two probe brackets are adjusted together so that the probe mechanism (17) is parallel to the magnetic bearing to be tested, so as to test the change in magnetic field intensity and distribution under different states.

9. A test system for loading and detecting magnetic field of a magnetic bearing according to claim 7, characterized in that: The probe mechanism (17) is composed of a carbon fiber connecting rod, a probe fixture and a Hall probe; wherein the upper carbon fiber connecting rod is connected to the yaw probe bracket of the probe bracket (16); there are two sets of probe fixtures, the upper one is connected to the carbon fiber connecting rod, and the lower one fixes the Hall probe through the joint action of the two sets of probes. The Hall probe can realize movement in six degrees of freedom and can test the magnetic field strength.

10. A test method for loading and detecting magnetic field of a magnetic bearing, characterized in that: The test method is implemented based on the test system according to any one of claims 1 to 9, and comprises the following steps: In the first step, the magnetic bearing to be tested is placed on the T-shaped turntable (5) and fixed using a clamp mechanism 6; The second step is to control the time-varying magnetic field detection device and place the detection part of the Hall probe at the part to be detected of the magnetic bearing. Specifically: Step 2.1, controlling the position of the optical platform (1) to be at an appropriate position inside the bracket (7) in the time-varying magnetic field detection device; Step 2.2, controlling the servo motors on the Y-axis motion mechanism (9), the Z-axis motion mechanism (10), the X-axis motion mechanism (11) and the turntable base (14) of the test device, so that the guide rail slider on each motion mechanism can move accurately in the X direction, the Y direction and the Z direction and rotate accurately along the Z axis, indirectly realizing the accurate movement of the Hall probe in the probe mechanism (17) in the three-dimensional space of the entire test system, so that the Hall probe can accurately reach the position to be tested; The third step is to control the displacement loading device to simulate different states of the magnetic bearing to be tested. During displacement loading, the Hall probe detects the change of its magnetic field in real time. Specifically: Step 3.1, controlling the servo motors on the X-axis motion mechanism (3) of the loading device, the Y-axis motion mechanism (4) of the loading device, the Z-axis lifting platform (2) and the T-type turntable (5), so that the guide slider on each motion mechanism can move accurately in the X-direction, the Y-direction and the Z-direction and rotate accurately along the Z-axis, indirectly driving the rotor of the magnetic bearing to be tested to move in various directions, thereby simulating different states required by the magnetic bearing test; Step 3.2, when the magnetic bearing to be tested moves under different working conditions, the real-time data signal is transmitted to the computer through the electric slip ring for processing to obtain the result.

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