CN111272115B - Motor concentricity comparison method, system and device and computer readable storage medium - Google Patents
Motor concentricity comparison method, system and device and computer readable storage medium Download PDFInfo
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- CN111272115B CN111272115B CN201911300644.1A CN201911300644A CN111272115B CN 111272115 B CN111272115 B CN 111272115B CN 201911300644 A CN201911300644 A CN 201911300644A CN 111272115 B CN111272115 B CN 111272115B
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- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
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Abstract
The invention provides a method, a system, a device and a computer readable storage medium for comparing the concentricity of a motor, wherein the method comprises the following steps: s1, numbering all motors: 1. 2, 3 … …; s2, respectively installing the motors 1, 2 and 3 … … on a user machine type, carrying out single air-out noise test, and calculating the frequency conversion according to the actual rotating speed of the motors, wherein the frequency conversion is equal to the actual rotating speed/60 of the motors; s3, collecting noises under different conversion frequencies when the motors 1, 2 and 3 … … work through a noise tester; s4, comparing the noise of the motors 1, 2 and 3 … … at the special rotating frequency point, and sequencing, wherein the motor with the minimum noise is the motor with the best concentricity of the stator and the rotor.
Description
Technical Field
The invention relates to the technical field of motor measurement, in particular to a method, a system and a device for comparing motor concentricity and a computer readable storage medium.
Background
Motor concentricity alignment is a basic method of equipment installation and is commonly used in equipment installation. In order to avoid the problems that the equipment generates larger vibration when rotating at high speed, the motor and a speed reducer bearing are damaged, the service life of the equipment is prolonged, and the requirement on large-scale and high-speed equipment for ensuring higher coaxiality is required when the equipment is installed, therefore, the concentricity alignment of the motor is very important and has high precision requirement in the equipment installation engineering, and the strict test is required before the equipment is in test operation to ensure the installation quality.
The existing air conditioner outdoor unit saves cost, an alternating current motor is often used for driving fan blades to rotate, and when dynamic eccentricity exists between a stator and a rotor of the motor and excitation is transmitted to a wind wheel and a shell, electromagnetic noise can be further amplified. In some areas where the power supply has a high harmonic content, the motor eccentricity problem can also exacerbate harmonic noise. Therefore, when the type of the motor is selected, a motor with a motor rotor and a shell with high concentricity needs to be selected, but the motor rotor and the shell are often not fast, simple and convenient to compare with other motors.
Therefore, a method for comparing concentricity of motors is provided to solve the problem that concentricity of different motors cannot be compared quickly in the prior art, which is one of the technical problems to be solved urgently by the technical personnel in the field.
Disclosure of Invention
The invention provides a method, a system and a device for comparing concentricity of a motor and a computer readable storage medium, which aim to solve the technical problem that the concentricity of a stator and a rotor of an alternating current motor cannot be compared quickly in the prior art.
In order to solve the problems, the invention discloses a method for comparing the concentricity of a motor, which comprises the following steps:
s1, numbering all motors: 1. 2, 3 … …;
s2, respectively installing the motors 1, 2 and 3 … … on a user machine type, carrying out single air-out noise test, and calculating the frequency conversion according to the actual rotating speed of the motors, wherein the frequency conversion is equal to the actual rotating speed/60 of the motors;
s3, collecting noises under different conversion frequencies when the motors 1, 2 and 3 … … work through a noise tester;
and S4, comparing the noise of the motors 1, 2 and 3 … … at the special rotating frequency points, and sequencing, wherein the motor with the minimum noise is the motor with the best concentricity of the stator and the rotor.
The application the comparison method of motor concentricity select different motors and carry out the concentricity that compares different motors when special commentaries on classics frequency point rotates noise value size, compare in prior art, select manual image measuring apparatu to carry out the method of judging to the concentricity, this application is measured the concentricity of motor under motor operating condition, and the measuring result is more accurate, and only need measure the noise of motor under different commentaries on classics frequencies, and external influence factor is less, has reduced the error of artificial measurement.
Furthermore, the special frequency conversion point is a point where the motor stator and the motor rotor generate a noise peak effect.
Under special commentaries on classics frequency point, rarely have other parts of motor to produce peak effect, very big the noise value that produces the noise and produce the motor stator rotor during operation in having avoided other parts during operation in the motor causes great influence, has improved the measurement accuracy to motor stator rotor during operation noise, has ensured measuring result's accuracy.
Furthermore, the special frequency conversion points are 200+ frequency conversion and 200-frequency conversion.
When there is the dynamic eccentricity between the motor stator rotor, the motor can produce 200+ -rotational frequency's electromagnetic force, this can embody two peak values on the noise test frequency spectrum, and the motor is few other parts and produces peak value effect moreover, just produce peak value effect, also be equal effect to different motors moreover, can not influence the relative peak value size of noise value between the motor, and motor stator rotor concentricity relevance degree is the highest.
Further, S4, comparing the noise of the motors 1, 2 and 3 … … at two special rotating frequency points, and sequencing, wherein the motor with the number reaching the minimum noise value is the motor with the best concentricity of the stator and the rotor.
Noise generated when the motors 1, 2 and 3 … … work is compared at two special rotating frequency points, and the accuracy of measuring the concentricity of the stator and the rotor of the motors 1, 2 and 3 … … in the working state is improved.
Furthermore, the motor needs to be heated for 15 minutes before the single air-out noise test is carried out.
The motor is preheated, the motor is ensured to run stably, other parts of the motor are prevented from generating noise due to resonance when the motor works under an unstable condition, a measuring result is inaccurate, and a large error exists.
Furthermore, the single air outlet noise test is not connected with an air conditioner indoor unit, and a compressor is not started.
Carry out the noise test to the motor under the condition of not linking air conditioner internal unit, not opening the compressor, the noise of having avoided air conditioner internal unit and compressor during operation to measuring the noise that motor during operation stator rotor produced causes the influence, when testing different motors simultaneously, is convenient for dismantle the change to different motors.
The motor concentricity comparison system compares the concentricity of the motor by adopting the motor concentricity comparison method.
Further, the comparison system of the concentricity of the motor comprises:
a noise analysis module capable of recording the noise of the motors 1, 2, 3 … … at different conversion frequencies and transmitting the recorded data to the main controller,
a main controller capable of fitting noise data of the motors 1, 2, 3 … … in the noise analysis module at different conversion frequencies,
and the graphic display module can display the fitting result of the main controller and can visually compare the sizes of the noises generated by the motors 1, 2 and 3 … … under different conversion frequencies.
The comparison method of the concentricity of the motor is realized through the conversion of the noise analysis module to noise data, the fitting of the noise data of the main controller and the setting of the graph display module to the display of the noise data.
A motor concentricity comparison device comprises a computer readable storage medium and a processor, wherein a computer program is stored in the computer readable storage medium, and when the computer program is read and executed by the processor, the motor concentricity comparison method is realized.
A computer-readable storage medium, in which a computer program is stored which, when read and executed by a processor, implements the above-described method for comparing motor concentricity.
To sum up, the motor concentricity comparison method takes the noise of the stator and the rotor of the motor at a special rotating frequency point as a measurement standard, and can rapidly, simply and conveniently compare the concentricity of the stator and the rotor of different motors.
Drawings
Fig. 1 is a schematic structural diagram of a method for comparing concentricity of a motor according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of noise spectra of a motor A and a motor B according to a method for comparing concentricity of motors in an embodiment of the invention;
fig. 3 is a schematic structural diagram of a system for comparing concentricity of a motor according to an embodiment of the present invention.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
Example 1:
as shown in fig. 1, a method for comparing concentricity of motors includes the steps of:
s1, numbering all motors: 1. 2, 3 … …;
s2, respectively installing the motors 1, 2 and 3 … … on a user machine type, carrying out single air-out noise test, and calculating the frequency conversion according to the actual rotating speed of the motors, wherein the frequency conversion is equal to the actual rotating speed/60 of the motors;
s3, collecting noises under different conversion frequencies when the motors 1, 2 and 3 … … work through a noise tester;
and S4, comparing the noise of the motors 1, 2 and 3 … … at the special rotating frequency points, and sequencing, wherein the motor with the minimum noise is the motor with the best concentricity of the stator and the rotor.
Furthermore, special commentaries on classics frequency point is the point that motor stator and rotor produced the noise peak value, and under special commentaries on classics frequency point, rarely there are other parts of motor to produce the peak value effect, very big avoid in the motor that other parts during operation produced the noise and cause great influence to the noise value that motor stator and rotor during operation produced, improved the measurement accuracy to motor during operation stator and rotor production noise, ensured measuring result's accuracy.
Furthermore, two special frequency conversion points are 200+ frequency conversion and 200-frequency conversion, when moving eccentricity exists between the stator and the rotor of the motor, the motor can generate electromagnetic force of 200 +/-frequency conversion, two peak values can be embodied on a noise test frequency spectrum, moreover, the motor rarely has other parts to generate a peak value effect, even if the peak value effect is generated, the motor also has an equivalent effect on different motors, the relative peak value size between the motors cannot be influenced, and the degree of correlation with the concentricity of the stator and the rotor of the motor is highest.
Furthermore, before the single-air-out noise test, the motor needs to be heated for 15 minutes, the motor is preheated, the motor is ensured to run stably, the motor is prevented from working under an unstable condition, the error of measuring noise is large, preferably, the placement position of the noise detector is related to the noise test standard of the use model of the motor, the placement position of the noise detector is determined according to the use model of the motor and the noise test standard, the noise generated by the stator and the rotor during the working of the motor can be more accurately measured, and preferably, the motor to be tested is placed on a desktop, so that the rotating shaft of the motor to be tested is 1m away from the bottom surface, and the front panel of the motor to be tested is 1m away from the noise detector.
Further, not alling oneself with the air conditioner indoor unit during single air-out noise test, not opening the compressor, not alling oneself with the air conditioner indoor unit, do not opening and carry out the noise test to the motor under the condition of compressor, the noise of having avoided air conditioner indoor unit and compressor during operation to produce causes the influence to the noise that the measuring motor during operation stator rotor produced, is convenient for change different motors simultaneously, and it is convenient to dismantle.
Example 2:
a method for comparing concentricity of motors comprises the following steps:
s1, numbering all motors: 1. 2, 3 … …;
s2, respectively installing the motors 1, 2 and 3 … … on a user machine type, carrying out single air-out noise test, and calculating the frequency conversion according to the actual rotating speed of the motors, wherein the frequency conversion is equal to the actual rotating speed/60 of the motors;
s3, collecting noises under different conversion frequencies when the motors 1, 2 and 3 … … work through a noise tester;
and S4, comparing the noise of the motors 1, 2 and 3 … … at two special rotating frequency points, and sequencing, wherein the numbered motor with the noise reaching the minimum value simultaneously is the motor with the best concentricity of the stator and the rotor.
Furthermore, special commentaries on classics frequency point is the point that motor stator and rotor produced the noise peak value, and under special commentaries on classics frequency point, rarely there are other parts of motor to produce the peak value effect, very big avoid in the motor that other parts during operation produced the noise and cause great influence to the noise value that motor stator and rotor during operation produced, improved the measurement accuracy to motor during operation stator and rotor production noise, ensured measuring result's accuracy.
Furthermore, two special frequency conversion points are 200+ frequency conversion and 200-frequency conversion, when moving eccentricity exists between the stator and the rotor of the motor, the motor can generate electromagnetic force of 200 +/-frequency conversion, two peak values can be embodied on a noise test frequency spectrum, moreover, the motor rarely has other parts to generate a peak value effect, even if the peak value effect is generated, the motor also has the equivalent effect to different motors, the relative peak value size of noise values between the motors cannot be influenced, and the degree of correlation with the concentricity of the stator and the rotor of the motor is highest.
Specifically, the implementation process of the motor concentricity comparison method provided by the application is as follows: numbering 1, 2 and 3 … … of a motor to be tested, installing the motor A on a user machine type, testing single air-out noise after the heat engine is operated for 15 minutes, calculating the frequency of the motor, wherein the frequency is equal to the actual rotating speed/60 of the motor, the heat engine can prevent the inaccurate measurement result when the motor is tested under the condition of not preheating for 15 minutes, an air conditioner internal machine is not connected during the single air-out noise test, a compressor is not started, the motor A is placed on a desktop during the noise test, a motor shaft of the motor A is 1m away from a bottom surface, a noise detector is 1m away from a front panel of the motor A, the noise values generated when the motor A works under different rotating frequencies are recorded, the motor A is detached, the motor B is installed, the single air-out noise test is performed after the heat engine is operated for 15 minutes, the noise values generated when the motor B works under different rotating frequencies are recorded, the motor B is detached, the single air-out noise test is carried out after a motor C is installed for 15 minutes, a noise value … … generated when a motor B works under different conversion frequencies is recorded, the noise values of Hertz of the motors 1, 2 and 3 … … under two special conversion frequency points are compared and marked as A +, A-, B +, B-, C +, C- …, the sizes of A +, B + and C + … are compared and sequenced, the sizes of A-, B-and C- … are compared and sequenced, the numbered motor reaching the minimum value is the motor with the best concentricity of the stator and the rotor, the special conversion frequency points are points at which the stator and the rotor of the motor generate noise peak effects and rarely generate peak effects of other parts of the motor, and the two special conversion frequency points selected by the application are 200+ conversion frequency and 200-conversion frequency.
Through the above process, it can be seen that: the application the comparison method of motor concentricity rotating electrical machines noise that the rotor produces at the during operation is as the standard of the different motor stator concentricity of contrast, compare and select manual image measuring apparatu to judge more accurately fast concentricity among the prior art, adopt moreover to measure in the rotor working process of stator, the measuring result has the possibility of error littleer, the measuring result is more effective promptly.
Referring to fig. 3, the dark frequency spectrum is motor a, the light frequency spectrum is motor B, the motor speed is 880rpm, the frequency is 14.7Hz, and the noise values of motor a at 200-frequency and 200+ frequency are 186Hz and 214Hz, so that it can be seen that at these two frequencies, the dark noise value is greater than the light noise value, and the concentricity of motor a is inferior to that of motor B.
Example 3:
as shown in fig. 2, a system for comparing concentricity of motors includes:
a noise analysis module capable of recording the noise of the motors 1, 2, 3 … … at different conversion frequencies and transmitting the recorded data to the main controller.
A master controller capable of fitting noise data of the motors 1, 2, 3 … … in the noise analysis module at different conversion frequencies.
And the graphic display module can display the fitting result of the main controller and can visually compare the sizes of the noises generated by the motors 1, 2 and 3 … … under different conversion frequencies.
Example 4:
the motor concentricity comparison device further comprises a computer readable storage medium and a processor, wherein the computer readable storage medium is used for storing a computer program, and the computer program is read by the processor and runs to realize the motor concentricity comparison method.
A computer-readable storage medium, in which a computer program is stored which, when read and executed by a processor, implements the above-described method for comparing motor concentricity.
Although the present invention is disclosed above, the present invention is not limited thereto. In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Various changes and modifications may be effected therein by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.
Claims (10)
1. A method for comparing concentricity of motors is characterized by comprising the following steps:
s1, numbering all motors: 1. 2, 3 … …;
s2, respectively installing the motors 1, 2 and 3 … … on a user machine type, carrying out single air-out noise test, and calculating the frequency conversion according to the actual rotating speed of the motors, wherein the frequency conversion is equal to the actual rotating speed/60 of the motors;
s3, collecting noises under different conversion frequencies when the motors 1, 2 and 3 … … work through a noise tester;
and S4, comparing the noise of the motors 1, 2 and 3 … … at the special rotating frequency points, and sequencing, wherein the motor with the minimum noise is the motor with the best concentricity of the stator and the rotor.
2. The method for comparing the concentricity of motors of claim 1, wherein the special rotation frequency point is a point where a stator and a rotor of the motor generate a noise peak effect.
3. The method for comparing the concentricity of motors in claim 2, wherein the special frequency conversion points are 200+ frequency conversion and 200-frequency conversion.
4. The method for comparing the concentricity of motors in claim 1, wherein S4 compares the noise levels of the motors 1, 2 and 3 … … at two special rotation frequency points, sequences the noise levels, and the motor with the number reaching the minimum noise level is the motor with the best concentricity of the stator and the rotor.
5. The method of claim 1, wherein the electrical machine is warmed up for 15 minutes before the single outlet noise test.
6. The method for comparing the concentricity of the motors as claimed in claim 1, wherein the single outlet noise test is carried out without connecting an air conditioner indoor unit and turning on a compressor.
7. A comparison system for concentricity of a motor, wherein the concentricity of a stator and a rotor of an alternating current motor is compared by the method for comparing concentricity of a motor according to any one of claims 1 to 6.
8. The system for comparing motor concentricity of claim 7, comprising:
a noise analysis module which can record the noise of the motors 1, 2 and 3 … … under different conversion frequencies and convert the recorded data into digital signals to be transmitted to the main controller,
a main controller capable of fitting noise data of the motors 1, 2, 3 … … in the noise analysis module at different conversion frequencies,
and the graphic display module can display the fitting result of the main controller and can visually compare the sizes of the noises generated by the motors 1, 2 and 3 … … under different conversion frequencies.
9. A comparison apparatus of motor concentricity, comprising a computer readable storage medium storing a computer program and a processor, the computer program being read and executed by the processor to implement the comparison method of motor concentricity according to any one of claims 1 to 6.
10. A computer-readable storage medium, characterized in that it stores a computer program which, when read and executed by a processor, implements the method of comparing motor concentricity according to any one of claims 1 to 6.
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| KR100540158B1 (en) * | 2004-04-08 | 2006-01-10 | 안재섭 | Valve driver |
| CN207050679U (en) * | 2017-06-26 | 2018-02-27 | 中广核达胜加速器技术有限公司 | A kind of accelerating tube magnet ring parallelism detecting device |
| CN206919853U (en) * | 2017-07-14 | 2018-01-23 | 浙江之江工程项目管理有限公司 | A kind of sonigauge |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101521417A (en) * | 2008-10-31 | 2009-09-02 | 卧龙电气集团股份有限公司 | Low-noise motor rotor |
| CN102620753A (en) * | 2011-02-22 | 2012-08-01 | 罗兰克斯两合有限公司 | Inductive position sensor |
| CN202133385U (en) * | 2011-05-19 | 2012-02-01 | 田陆 | Continuous casting liquid core on-line detection system and sensor location apparatus thereof |
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