Magnetic suspension system protection bearing high-precision position detection method

Abstract

The invention discloses a high-precision position detection method for a protection bearing of a magnetic suspension system. The method comprises the following steps: connecting an inductance test system containing an excitation source with a magnetic bearing coil through a four-wire method; establishing a communication link between the inductance test system and an upper computer data processing system; applying a low-frequency alternating current signal to the magnetic bearing coil; adjusting the position of the rotor to enable the rotor to be in a limit position for protecting a bearing; measuring the inductance value of the magnetic bearing coil at the limit position; substituting the actually measured inductance value into the position deviation detection model to calculate the deviation value of the mounting position of the protective bearing; the deviation value obtained through calculation is compared with an allowable deviation range, and if the deviation value exceeds the range, an alarm signal is sent out; and if the deviation value is within the range, determining that the mounting position is normal. According to the invention, the high-precision and high-reliability detection of the installation position of the protection bearing is realized, an external closed-loop control system is not needed, and the detection of the installation position of the protection bearing of a magnetic suspension system on a production line can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of key component detection of magnetic suspension systems, and in particular relates to a high-precision position detection method for a protective bearing of a magnetic suspension system. Background Art

[0002] In magnetic levitation systems, the mounting position of the protective bearing plays a crucial role in determining the sensor calibration range and the range of motion of the suspended rotor. Misalignment of the protective bearing's mounting position can cause misalignment between the sensor's detection center and the magnetic center of the magnetic bearing, exacerbating vibration during operation. Therefore, accurate inspection of the protective bearing's mounting position is crucial.

[0003] Currently, existing protective bearing detection methods generally require an external magnetic bearing control system. By testing the magnetic bearing control current at the center of the sensor, the installation position of the protective bearing is determined to be deviated. However, this detection method is inefficient and cannot be tested in a timely manner during the processing and assembly process, making it unsuitable for large-scale batch magnetic levitation system testing. Based on the currently retrieved patents related to magnetic levitation systems, how to timely and accurately evaluate the installation status of protective bearings during the processing and assembly process remains a difficult problem facing the industrialization of magnetic levitation motors. Summary of the Invention

[0004] To solve the above technical problems, the present invention proposes a high-precision position detection method for the protective bearing of a magnetic levitation system. Based on the characteristic that the inductance of the magnetic bearing coil changes with the rotor air gap length, the method detects the coil inductance value at the extreme position of the rotor under the constraint of the protective bearing, thereby achieving high-precision and high-reliability detection of the installation position of the protective bearing. Without the need for an external closed-loop control system, the installation position detection of the protective bearing of the magnetic levitation system can be carried out on the production line.

[0005] To achieve the above objectives, the present invention provides a high-precision position detection method for a protective bearing of a magnetic suspension system, comprising:

[0006] Connect the inductance test system including the excitation source to the magnetic bearing coil through the four-wire method;

[0007] Establish a communication link between the inductance test system and the host computer data processing system;

[0008] applying a low-frequency alternating current signal to the magnetic bearing coil;

[0009] Adjust the rotor position to the extreme position to protect the bearing;

[0010] Measure the inductance of the magnetic bearing coil at the extreme position;

[0011] Substitute the measured inductance value into the position deviation detection model to calculate the protective bearing installation position deviation value;

[0012] Compare the calculated deviation value with the allowable deviation range. If the deviation value exceeds the range, an alarm signal is issued; if the deviation value is within the range, it is confirmed that the installation position is normal.

[0013] Optionally, the position deviation detection model is a nonlinear mathematical model, which is established based on the magnetic pole area and core material properties of the magnetic bearing and is used to associate the protective bearing installation position deviation with the inductance value change characteristic parameters.

[0014] Optionally, the process of connecting the inductance test system including the excitation source to the magnetic bearing coil through the four-wire method includes adopting the four-wire method to ensure stable transmission of the measurement signal.

[0015] Optionally, the frequency of the low-frequency alternating current signal is less than 50 Hz.

[0016] Optionally, the extreme position includes multiple directional extreme positions, specifically x+, x-, y+, y-, z+, and z- positions; and the process of adjusting the rotor position includes adjusting to the extreme position in each direction in turn.

[0017] Optionally, the process of measuring the inductance value includes testing the inductance value of two sets of coils in each direction; and the process of calculating the deviation value of the protective bearing installation position calculates the deviation value based on the measured inductance value.

[0018] Optionally, the allowable deviation range is set based on the air gap length of the magnetic bearing; the process of issuing the alarm signal includes displaying the deviation value and position information through the host computer interface.

[0019] Technical effects of the present invention:

[0020] (1) This invention utilizes the correlation between the inductance characteristics of the magnetic bearing coil and the installation position of the protective bearing for detection. By accurately capturing subtle changes in the inductance value, it achieves high-precision detection of the protective bearing installation position at the level of ±0.01mm. Compared with traditional detection methods, this greatly improves detection accuracy and efficiency, meeting the requirements of high-precision magnetic levitation industrial applications.

[0021] (2) The present invention breaks through the limitations of traditional detection technology and innovatively applies an excitation current to directly measure the inductance of the magnetic bearing coil. There is no need to build a complex external closed-loop system. The detection process can be seamlessly embedded in the assembly production line of the magnetic levitation system. Through real-time and accurate inductance data collection and analysis, it is possible to quickly detect slight deviations in the installation position of the protective bearing during the assembly stage. Compared with traditional methods, this pre-detection mode effectively avoids system operation failures caused by installation position deviations, greatly improves the safety and stability of the magnetic levitation system throughout its life cycle, and provides a solid guarantee for the efficient production and reliable operation of magnetic levitation equipment.

[0022] (3) The method proposed in the present invention does not require the installation of additional complex detection sensors, and directly uses the existing magnetic bearing coils in the magnetic levitation system for detection, thereby reducing the R&D and production costs of the detection system.

[0023] (4) The detection principle adopted by the present invention is based on the inductance characteristics of the magnetic bearing coil, which is not affected by factors such as ambient light and dust, reducing detection errors and misjudgments caused by environmental factors, and ensuring the accuracy and reliability of the detection results.

[0024] (5) This technical solution is applicable to the installation position detection of protective bearings of various types of magnetic levitation systems. It has wide adaptability and versatility and can provide reliable detection support for magnetic levitation systems in different application scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0026] Figure 1 This is a schematic diagram of radial position detection of a high-precision position detection method for a protective bearing of a magnetic suspension system according to an embodiment of the present invention;

[0027] Figure 2 This is a schematic diagram of axial position detection of a high-precision position detection method for a protective bearing of a magnetic suspension system according to an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the radial limit detection position of a high-precision position detection method for a protective bearing of a magnetic suspension system according to an embodiment of the present invention;

[0029] Figure 4 This is a schematic diagram of the axial limit detection position of a high-precision position detection method for a protective bearing of a magnetic suspension system according to an embodiment of the present invention;

[0030] Figure 5 This is a flow chart of a method for high-precision position detection of a protective bearing in a magnetic suspension system according to an embodiment of the present invention;

[0031] Figure numerals: 1- radial magnetic bearing; 2- inductance test system including excitation source; 3- host computer system; 4- axial magnetic bearing. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0033] It should be noted that the steps shown in the flowcharts of the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and that, although a logical order is shown in the flowcharts, in some cases, the steps shown or described can be executed in an order different from that shown here.

[0034] like Figure 5 As shown, this embodiment provides a high-precision position detection method for a protective bearing of a magnetic suspension system, comprising:

[0035] Connect the inductance test system including the excitation source to the magnetic bearing coil through the four-wire method;

[0036] Establish a communication link between the inductance test system and the host computer data processing system;

[0037] applying a low-frequency alternating current signal to the magnetic bearing coil;

[0038] Adjust the rotor position to the extreme position to protect the bearing;

[0039] Measure the inductance of the magnetic bearing coil at the extreme position;

[0040] Substitute the measured inductance value into the position deviation detection model to calculate the protective bearing installation position deviation value;

[0041] Compare the calculated deviation value with the allowable deviation range. If the deviation value exceeds the range, an alarm signal is issued; if the deviation value is within the range, it is confirmed that the installation position is normal.

[0042] Specifically, the implementation process of this embodiment includes:

[0043] Combining structural parameters such as the magnetic pole area and core material properties of the magnetic bearing, a nonlinear mathematical model is established between the protective bearing installation position deviation and the characteristic parameters of the magnetic bearing coil inductance value change;

[0044] Reliably connect the inductance test system containing the excitation source to the magnetic bearing coil to ensure stable transmission of the measurement signal, and sequentially test the inductance value of the rotor at the extreme positions (x+, x-, y+, y-, z+, z-) that protect the bearing.

[0045] A communication link is established between the inductance test system containing the excitation source and the host computer system, and the measured data is transmitted to the host computer system. The measured inductance is then substituted into the established position deviation detection model to calculate the installation position deviation value of the protective bearing. This calculated position deviation value is compared with the pre-set allowable deviation range (determined by the magnetic bearing parameters, usually not exceeding 15% of the magnetic bearing air gap length). If the position deviation value exceeds the allowable range, an alarm signal is issued, and the specific deviation value and position information are displayed on the host computer interface, reminding the staff to adjust the installation position of the protective bearing in a timely manner. If the position deviation value is within the allowable range, it indicates that the protective bearing installation position is normal and has passed the test.

[0046] like Figure 1 As shown, the x-direction and y-direction coils of the radial magnetic bearing are successively connected to the inductance test system through wires, and the inductance test system is connected to the host computer system through RS-232 / RS-485 and other data transmission lines, thereby transmitting the inductance test value to the host computer system, where 1- radial magnetic bearing; 2- inductance test system with excitation source; 3- host computer system;

[0047] like Figure 2 As shown, the z-direction coil of the axial magnetic bearing is successively connected to the inductance test system, and the inductance test system is connected to the host computer system via RS-232 / RS-485 and other data transmission lines, thereby transmitting the inductance test value to the host computer system. 2-Inductance test system with excitation source; 3-Host computer system; 4-Axial magnetic bearing.

[0048] like Figure 3 As shown, it means that the rotor is located at the radial extreme positions on both sides of the protective bearing.

[0049] like Figure 4 As shown, it means that the rotor is located at the extreme positions on both sides of the axial direction of the protective bearing.

[0050] This embodiment also provides a high-precision position detection device for a magnetic suspension system protective bearing, comprising:

[0051] Magnetic levitation system to be tested, inductance test system including excitation source, and host computer system;

[0052] The inductance test system is used to detect the inductance value of the magnetic bearing when the rotor is close to the protective bearing, and the host computer system is used to calculate the installation position deviation value of the protective bearing based on the measured inductance value.

[0053] Detection device connection: Reliably connect the inductance test system to the magnetic bearing coil in the magnetic levitation system to be tested through the four-wire method to ensure stable transmission of the measurement signal; at the same time, establish a communication link between the inductance test system and the host computer system to form a complete detection data transmission path.

[0054] Changes in the protective bearing position will cause changes in the magnetic circuit reluctance, which in turn affects the inductance value of the magnetic bearing coil. In addition, when the frequency of the electrical signal passed into the magnetic bearing coil is too high, the eddy current effect will cause the reluctance of the test circuit to change, affecting the air gap length detection. Therefore, during the test, a low-frequency (less than 50Hz) AC signal is introduced into the magnetic bearing coil to eliminate the influence of the eddy current effect, and the protective bearing position is detected based on the low-frequency inductance value of the magnetic bearing coil.

[0055] The following is an example of the detection of the protective bearing position in the x direction: adjust the rotor position to the protective bearing x+ limit position, and test the inductance values ​​of the two sets of coils in the x direction L1 (x+) and L2 (x+); continue to adjust the rotor position to the protective bearing x- limit position, and test the inductance values ​​of the two sets of coils in the x direction L1 (x-) and L2 (x-); according to The value of determines the protective bearing installation deviation. When the value is close to 0, the protective bearing installation position deviation is close to 0. The larger the value, the greater the installation error. The inductance deviation threshold is designed according to the magnetic bearing parameter structure.

[0056] The above are merely preferred embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A high-precision position detection method for a magnetic suspension system protective bearing, characterized in that: include: Connect the inductance test system including the excitation source to the magnetic bearing coil through the four-wire method; Establish a communication link between the inductance test system and the host computer data processing system; applying a low-frequency alternating current signal to the magnetic bearing coil; Adjust the rotor position to the extreme position to protect the bearing; Measure the inductance of the magnetic bearing coil at the extreme position; Substitute the measured inductance value into the position deviation detection model to calculate the protective bearing installation position deviation value; Compare the calculated deviation value with the allowable deviation range. If the deviation value exceeds the range, an alarm signal is issued; if the deviation value is within the range, it is confirmed that the installation position is normal.

2. The high-precision position detection method for a magnetic suspension system protective bearing according to claim 1, characterized in that: The position deviation detection model is a nonlinear mathematical model established based on the magnetic pole area and core material properties of the magnetic bearing, and is used to associate the protective bearing installation position deviation with the inductance value change characteristic parameters.

3. The high-precision position detection method for a magnetic suspension system protective bearing according to claim 1, characterized in that: The process of connecting the inductance test system including the excitation source to the magnetic bearing coil through the four-wire method includes adopting the four-wire method to ensure stable transmission of the measurement signal.

4. The high-precision position detection method for a magnetic suspension system protective bearing according to claim 1, characterized in that: The frequency of the low-frequency alternating current signal is less than 50 Hz.

5. The high-precision position detection method for a magnetic suspension system protective bearing according to claim 1, characterized in that: The extreme positions include multiple directional extreme positions, specifically x+, x-, y+, y-, z+, and z- positions; the process of adjusting the rotor position includes adjusting to the extreme positions in each direction in sequence.

6. The high-precision position detection method for a magnetic suspension system protective bearing according to claim 1, characterized in that: The process of measuring the inductance value includes testing the inductance value of two sets of coils in each direction; the process of calculating the deviation value of the protective bearing installation position calculates the deviation value based on the measured inductance value.

7. The high-precision position detection method for a magnetic suspension system protective bearing according to claim 1, characterized in that: The allowable deviation range is set based on the air gap length of the magnetic bearing; the process of issuing the alarm signal includes displaying the deviation value and position information through the host computer interface.

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