Method for detecting assembly state of shielding motor containing electromagnetic bearing

Abstract

The invention relates to a method for detecting the assembly state of a shielded motor, in particular to a method for detecting the assembly state of a shielded motor with an electromagnetic bearing. The invention aims to solve the problem that the existing shield motor assembly state detection method performs detection by means of manual visual detection, conventional mechanical tools, displacement sensors and the like, but the detection of the assembly state after assembly cannot be realized by means of the methods. The method comprises the following steps: step 1, determining a detection reference; the detection reference comprises an axial reference and a radial reference; step 2, axial stator assembly state detection; verifying whether the stator end face in the axial direction is parallel to the shafting reference surface; 3, the assembling state of the axial electromagnetic thrust disc is detected; 4, detecting the assembly state of the protection bearing in the axial direction; 5, detecting the concentricity of the assembling state of the radial upper and lower protection bearing seats; and 6, detecting the parallelism of the upper and lower radial protection bearing seats relative to the radial reference. The invention belongs to the technical field of shielding motors.

Description

Technical Field

[0001] The invention relates to a method for detecting an assembly state of a shielded motor, and belongs to the technical field of shielded motors. Background Art

[0002] Existing methods for detecting the assembly status of shielded motors are to perform detection through manual visual inspection, conventional mechanical tools, displacement sensors, etc., but these methods cannot detect the assembly status after the assembly is completed.

[0003] The invention patent with publication number CN113422540B and application date June 28, 2021, discloses a motor initial state detection device and motor initial state detection method. The device includes a sampling module, a comparison module and a processing module; wherein: the sampling module is used to collect the two back electromotive forces of the motor and send the two back electromotive forces to the comparison module; the comparison module is used to obtain a comparison signal based on the two back electromotive forces and send the comparison signal to the processing module; the processing module is used to receive and judge the initial state of the motor based on the comparison signal. By collecting the two back electromotive forces and obtaining a comparison signal through the comparison module, and then matching the corresponding startup state through the comparison signal, it is possible to reduce the number of chip pins and comparators, reduce hardware resources, and save costs.

[0004] The invention patent with publication number CN110703096B and application date October 29, 2019 discloses a method, device, equipment and storage medium for detecting the working state of a motor. The method for detecting the working state of the motor includes: setting a reference voltage value according to the rated voltage of the motor; monitoring the three-phase voltage of the motor during the operation of the motor, and obtaining the minimum voltage value and the minimum voltage phase to which the minimum voltage value belongs; comparing the minimum voltage value with the other two-phase voltage values ​​and the reference voltage value to determine the working state of the motor. The embodiment of the present invention sets the reference voltage value of the motor protection device based on the rated voltage of different motors, thereby supporting the protection of motors of various voltage standards. In addition, the three-phase voltage value of the motor is monitored during the operation of the motor, and the working state of the motor is determined based on the comparison between the monitored value and the reference voltage value, thereby improving the accuracy of judging the phase-loss working state of the motor during the operation of the motor.

[0005] However, the above two technologies can only detect the working status of the motor, but cannot detect the assembly status of the motor. Summary of the Invention

[0006] The present invention aims to solve the problem that existing methods for detecting the assembly status of shielded motors are performed by manual visual inspection, conventional mechanical tools, displacement sensors, etc., but these methods are unable to detect the assembly status after assembly is completed. Therefore, a method for detecting the assembly status of a shielded motor containing an electromagnetic bearing is proposed.

[0007] The technical solution adopted by the present invention to solve the above problems is: the steps of the present invention include:

[0008] Step 1: Determine the detection benchmark; the detection benchmark includes the axial benchmark and the radial benchmark;

[0009] Step 2: Axial stator assembly status inspection: verify whether the axial stator end face is parallel to the shaft reference plane;

[0010] Step 3: Detect the assembly status of the axial electromagnetic thrust disc; detect the installation status of the axial electromagnetic thrust disc plane relative to the verticality of the rotating shaft;

[0011] Step 4: Check the assembly status of the axial protection bearing; verify the installation status of the parallelism of the lower end surface of the axial protection bearing relative to the shafting reference plane;

[0012] Step 5: Check the concentricity of the radial upper and lower protective bearing seats in the assembled state;

[0013] Step 6: Check the parallelism of the upper and lower radial protection bearing seats relative to the radial reference.

[0014] Furthermore, axial reference: in the natural state, the lower end surface of the thrust plate of the protective bearing is tightly fitted with the upper end surface of the axial lower protective bearing. This plane is used as the axial reference plane to detect the assembly status of the axial stator, electromagnetic thrust plate and axial protective bearing;

[0015] Radial datum: The line connecting the center point of the central section of the radial protection bearing and the center point of the axial datum plane is used as the radial datum line. This datum is used to detect the assembly status of the upper and lower radial protection bearings.

[0016] Furthermore, the basis for detecting the axial stator assembly status is as follows: when the rotor is axially suspended, the axial electromagnetic thrust disk is parallel to the axial stator end face. If the axial stator end face is not parallel to the shaft system reference, the radial electromagnetic bearing rotor position detected by the radial eddy current displacement sensor will produce a radial position offset compared to before adsorption, so as to judge whether the axial stator end face is parallel to the shaft system reference plane; the specific operation is to record the output signals of the upper and lower radial eddy current displacement sensors in the natural state to determine the initial radial position information; record the upper and lower radial eddy current output signals during axial suspension; and compare the front and rear position signals after repeating multiple times. If they are consistent or the difference is not large, it means that the axial stator installation tolerance is within a reasonable range.

[0017] Furthermore, the method for detecting the assembly status of the axial upper protection bearing is as follows: power is applied to the upper and lower X+ directions at the same time, the rotor is adsorbed on the X+ side, and the eddy current reading in the X+ direction is read; then current is applied to the upper axial stator to make the upper end face of the axial protection thrust plate completely contact with the axial upper protection bearing, and the eddy current reading in the X+ direction at this time is read; at this time, the parallelism of the upper end face of the axial protection bearing compared to the lower end face of the axial protection bearing is reflected by the difference in the eddy current reading in the lower X+ direction.

[0018] Furthermore, the concentricity of the radial upper and lower protective bearing seat assembly state is detected by the following method:

[0019] First, suspend the rotor at the center position of the axial and upper radial directions, record the eddy current signal output of the lower radial rotor in the X and Y directions, and observe whether the lower radial eddy current signal output has reached or is close to the limit position signal during calibration; if not, the suspension position of the upper radial rotor can be changed so that the lower radial rotor is also offset, and the signal measured by the lower radial eddy current displacement sensor gradually approaches the limit position signal; the eccentricity of the upper and lower radial protective bearing seats can be inferred from the difference in eddy current signal output in the same direction of the upper and lower radial directions.

[0020] Furthermore, the parallelism of the upper and lower radial protection bearing seats relative to the radial reference is detected by the following method:

[0021] For the upper and lower X directions, during radial calibration, record the eddy current signals at the upper and lower X- extreme positions. Then, simultaneously pass current through the upper X+ and lower X- windings, and record the eddy current signal of the lower X- at this time. If tilted, the front and rear lower X-direction eddy current displacement sensors will produce a signal difference. The tilt angle can be calculated based on this signal difference and the shaft system parameters.

[0022] The beneficial effects of the present invention are:

[0023] 1. The present invention can detect the assembly status of the shielded motor after assembly and provide guidance for subsequent assembly status improvement;

[0024] 2. Compared with traditional detection methods, the present invention is more accurate and reliable;

[0025] 3. The present invention can be applied to motor assembly status detection in high-risk working environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a simplified schematic diagram of the shielded motor shaft system with electromagnetic bearings;

[0027] Figure 2 is a reference schematic diagram;

[0028] Figure 3 This is a schematic diagram of the suspension state when the stator is not parallel to the axial reference in the axial direction;

[0029] Figure 4 This is a schematic diagram showing that the electromagnetic thrust plate is not completely perpendicular to the rotating shaft;

[0030] Figure 5 This is a schematic diagram of the state detection when the axial protection bearing is not parallel to the axial reference;

[0031] Figure 6 This is a schematic diagram of the status detection when the radial upper and lower protection bearings are not concentric;

[0032] Figure 7 This is a schematic diagram of the state detection when the lower radial protection bearing does not meet the parallelism relative to the radial system reference;

[0033] Figure 1 In the figure, 1-axial eddy current displacement sensor; 2-upper axial stator; 3-axial electromagnetic thrust plate; 4-lower axial stator; 5-upper X+eddy current displacement sensor; 6-upper radial rotor; 7-upper axial protection bearing; 8-axial protection thrust plate; 9-lower axial protection bearing; 10-upper radial protection bearing seat; 11-upper radial protection bearing; 12-lower radial protection bearing seat; 13-lower radial protection bearing; 14-lower X+eddy current displacement sensor; 15-lower radial rotor; 16-rotor; 17-lower Y+eddy current displacement sensor; 18-upper Y+eddy current displacement sensor. DETAILED DESCRIPTION

[0034] Specific implementation method 1: Figure 1 As shown, a method for detecting the assembly status of a shielded motor containing an electromagnetic bearing comprises the following specific steps:

[0035] Step 1: Determine the detection benchmark; the detection benchmark includes the axial benchmark and the radial benchmark;

[0036] Step 2: Axial stator assembly status inspection: verify whether the axial stator end face is parallel to the shaft reference plane;

[0037] Step 3: Detect the assembly status of the axial electromagnetic thrust disc; detect the installation status of the axial electromagnetic thrust disc plane relative to the verticality of the rotating shaft;

[0038] Step 4: Check the assembly status of the axial protection bearing; verify the installation status of the parallelism of the lower end surface of the axial protection bearing relative to the shafting reference plane;

[0039] Step 5: Check the concentricity of the radial upper and lower protective bearing seats in the assembled state;

[0040] Step 6: Check the parallelism of the upper and lower radial protection bearing seats relative to the radial reference.

[0041] Among them, axial reference: in the natural state, the lower end surface of the protective bearing thrust plate is tightly fitted with the upper end surface of the axial lower protective bearing. This plane is used as the axial reference plane to detect the assembly status of the axial stator, electromagnetic thrust plate and axial protective bearing;

[0042] Radial datum: The line connecting the center point of the central section of the radial protection bearing and the center point of the axial datum plane is used as the radial datum line. This datum is used to detect the assembly status of the upper and lower radial protection bearings.

[0043] Among them, such as Figure 3 As shown, the axial stator assembly status inspection is mainly to verify whether the stator end face in the axial direction is parallel to the shaft system reference plane.

[0044] The detection is based on the fact that when the rotor is axially suspended, the axial electromagnetic thrust disc is parallel to the axial stator end face. If the axial stator end face is not parallel to the shaft system reference, the radial electromagnetic bearing rotor position detected by the radial eddy current displacement sensor will produce a radial position offset compared to before adsorption. This is used to determine whether the axial stator end face is parallel to the shaft system reference plane. The specific operation is to record the output signals of the upper and lower radial eddy current displacement sensors in a natural state to determine the initial radial position information; and record the upper and lower radial eddy current output signals during axial suspension. After repeated multiple times, compare the front and rear position signals. If they are consistent or the difference is not large, it means that the axial stator installation tolerance is within a reasonable range.

[0045] Among them, such as Figure 4 As shown in the figure, the axial electromagnetic thrust plate assembly status test primarily checks the perpendicularity of the plate's plane relative to the shaft. Under natural conditions, the shielded motor is filled with water, powered on, and the rotor operates briefly. If the plate's plane is not perpendicular to the shaft, the axial eddy current signal will appear as a periodic fluctuation when observed on an oscilloscope. The period of this fluctuation signal represents one full rotation of the shaft, and the peak-to-peak value within a period represents the electromagnetic thrust plate's runout.

[0046] Among them, such as Figure 5 As shown in the figure, the axial upper protection bearing assembly status test primarily verifies the parallelism of the lower end face of the axial upper protection bearing relative to the shafting reference plane. The corresponding test method is to simultaneously apply power to the upper and lower X+ directions, attach the rotor to the X+ side, and read the eddy current reading in the X+ direction. Current is then applied to the upper axial stator, ensuring that the upper end face of the axial protection thrust plate is in full contact with the axial upper protection bearing, and the eddy current reading in the X+ direction is read. The difference in the eddy current reading in the lower X+ direction reflects the parallelism of the upper end face of the axial protection bearing relative to the lower end face of the axial protection bearing.

[0047] Among them, such as Figure 6As shown, the concentricity of the assembly state of the radial upper and lower protection bearing seats is detected because the calibration range of the radial eddy current displacement sensor is the inner diameter of the radial upper and lower protection bearings. If the eccentricity of the upper and lower protection bearings is too large, it will seriously affect the verticality of the rotor shaft and the axial reference during radial suspension, thereby interfering with the axial suspension. The corresponding detection method is to first suspend the rotor in the center position of the axial and upper radial directions, record the eddy current signal output of the lower radial rotor in the X and Y directions at this time, and observe whether the lower radial eddy current signal output has reached or is close to the limit position signal during calibration. If not, the suspension position of the upper radial rotor can be changed so that the lower radial rotor is also offset, and the signal measured by the lower radial eddy current displacement sensor gradually approaches the limit position signal. The eccentricity of the upper and lower radial protection bearing seats is calculated by the difference in the eddy current signal output in the same direction of the upper and lower radial directions.

[0048] Among them, such as Figure 7 As shown in the figure, the detection of the parallelism of the upper and lower radial protection bearing seats relative to the radial reference needs to be carried out after confirming that the concentricity of the protection bearing seats meets the requirements. Taking the upper radial protection bearing meeting the parallelism requirements relative to the radial system reference, while the lower radial protection bearing does not meet the parallelism requirements as an example, the corresponding detection method is for the upper and lower X directions (the same applies to the Y direction). During radial calibration, the eddy current signals of the upper and lower X- extreme positions are recorded, and then current is passed through the upper X+ and lower X- windings at the same time, and the eddy current signal of the lower X- at this time is recorded. If it is tilted, the front and rear lower X-direction eddy current displacement sensors will produce a signal difference, and the tilt angle can be calculated based on the signal difference and the shaft system parameters.

[0049] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical content disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement of the above embodiments made according to the technical essence of the present invention, within the spirit and principles of the present invention, without departing from the content of the technical solution of the present invention, shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for detecting the assembly status of a shielded motor containing an electromagnetic bearing, characterized in that: The specific steps include: Step 1: Determine the detection benchmark; the detection benchmark includes the axial benchmark and the radial benchmark; Step 2: Axial stator assembly status inspection: verify whether the axial stator end face is parallel to the shaft reference plane; Step 3: Detect the assembly status of the axial electromagnetic thrust disc; detect the installation status of the axial electromagnetic thrust disc plane relative to the verticality of the rotating shaft; Step 4: Check the assembly status of the axial protection bearing; verify the installation status of the parallelism of the lower end surface of the axial protection bearing relative to the shafting reference plane; Step 5: Check the concentricity of the radial upper and lower protective bearing seats in the assembled state; Step 6: Check the parallelism of the upper and lower radial protection bearing seats relative to the radial reference.

2. The method for detecting the assembly status of a shielded motor containing an electromagnetic bearing according to claim 1, characterized in that: Axial reference: In the natural state, the lower end surface of the protective bearing thrust plate is tightly fitted with the upper end surface of the axial lower protective bearing. This plane is used as the axial reference plane to detect the assembly status of the axial stator, electromagnetic thrust plate and axial protective bearing; Radial datum: The line connecting the center point of the central section of the radial protection bearing and the center point of the axial datum plane is used as the radial datum line. This datum is used to detect the assembly status of the upper and lower radial protection bearings.

3. The method for detecting the assembly status of a shielded motor containing an electromagnetic bearing according to claim 1, characterized in that: The basis for axial stator assembly status detection is: when the rotor is axially suspended, the axial electromagnetic thrust plate is parallel to the axial stator end face. If the axial stator end face is not parallel to the shaft system reference, the radial electromagnetic bearing rotor position detected by the radial eddy current displacement sensor will produce a radial position offset compared to before adsorption, so as to judge whether the axial stator end face is parallel to the shaft system reference plane; the specific operation is to record the output signals of the upper and lower radial eddy current displacement sensors in the natural state to determine the initial radial position information; record the upper and lower radial eddy current output signals during axial suspension; compare the front and rear position signals after repeated multiple times. If they are consistent or the difference is not large, it means that the axial stator installation tolerance is within a reasonable range.

4. The method for detecting the assembly status of a shielded motor containing an electromagnetic bearing according to claim 1, characterized in that: The method for detecting the assembly status of the axial upper protection bearing is as follows: energize the upper and lower X+ directions simultaneously, adsorb the rotor on the X+ side, and read the eddy current reading in the X+ direction; then, apply current to the upper axial stator so that the upper end face of the axial protection thrust plate is completely in contact with the axial upper protection bearing, and read the eddy current reading in the X+ direction at this time; at this time, the difference in the eddy current reading in the lower X+ direction reflects the parallelism of the upper end face of the axial protection bearing compared to the lower end face of the axial protection bearing.

5. The method for detecting the assembly status of a shielded motor containing an electromagnetic bearing according to claim 1, characterized in that: The concentricity of the radial upper and lower protective bearing seat assembly status is detected by the following method: First, suspend the rotor at the center position of the axial and upper radial directions, record the eddy current signal output of the lower radial rotor in the X and Y directions, and observe whether the lower radial eddy current signal output has reached or is close to the limit position signal during calibration; if not, the suspension position of the upper radial rotor can be changed so that the lower radial rotor is also offset, and the signal measured by the lower radial eddy current displacement sensor gradually approaches the limit position signal; the eccentricity of the upper and lower radial protective bearing seats can be inferred from the difference in eddy current signal output in the same direction of the upper and lower radial directions.

6. The method for detecting the assembly status of a canned motor containing an electromagnetic bearing according to claim 1, characterized in that: The parallelism of the upper and lower radial protection bearing seats relative to the radial reference is detected by the following method: For the upper and lower X directions, during radial calibration, record the eddy current signals at the upper and lower X- extreme positions. Then, simultaneously pass current through the upper X+ and lower X- windings, and record the eddy current signal of the lower X- at this time. If tilted, the front and rear lower X-direction eddy current displacement sensors will produce a signal difference. The tilt angle can be calculated based on this signal difference and the shaft system parameters.

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