Motor vibration detection method

Abstract

The invention discloses a motor vibration detection method, which comprises the following steps: fixing an air conditioner indoor unit on a test platform, fixing a fiber grating sensor on a motor of the air conditioner indoor unit, connecting the fiber grating sensor to a demodulator, and connecting the demodulator to a processing terminal; the air conditioner indoor unit is started to operate a motor; a fiber grating sensor is used for collecting a vibration signal generated by vibration of the motor and transmitting the vibration signal to a demodulator; demodulating the vibration signal by using a demodulator to obtain a central wavelength drift distance, and sending the central wavelength drift distance to a processing terminal; and the central wavelength drift distance is calculated by using the processing terminal, and the acceleration of the vibration signal is obtained and displayed. The fiber bragg grating sensor is matched with the demodulator to detect the vibration signal, the fiber bragg grating sensor has the anti-electromagnetic interference capability, more accurate vibration detection can be realized, and real-time testing can be realized without depending on historical parameters, so that the delivery test effect of the air conditioner indoor unit motor is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air conditioners, and in particular to a motor vibration detection method. Background Art

[0002] Traditional motor vibration detection mainly relies on piezoelectric sensors, but piezoelectric sensors are easily affected by electromagnetic interference during motor operation, resulting in large errors in test results, which in turn affects the reliability of product performance evaluation.

[0003] In the prior art, patent CN118656719A discloses a three-phase asynchronous motor fault diagnosis method based on the predicted value of the motor vibration signal. This method uses a single diagnostic model for prediction, but the model constraints are limited and there are many uncertain factors. It is difficult to apply to vibration detection of various motors and the reliability is insufficient. Another patent CN118643412A discloses a wind turbine generator fault warning method. This method constructs a variational autoencoder model by establishing a sample set of generator vibration and operation data under different health states. However, this method is too dependent on historical vibration data and lacks timeliness, and cannot be applied to the real-time diagnosis needs of subsequent motor groups.

[0004] In summary, the existing technology has the problems of relying on historical data and poor anti-interference ability in motor vibration detection. An improved motor vibration detection method is urgently needed to overcome these shortcomings in order to improve the performance and user experience of air-conditioning products. Summary of the invention

[0005] The embodiment of the present invention provides a motor vibration detection method, which aims to solve the problems of poor anti-interference ability and reliance on historical data in the motor vibration detection in the prior art.

[0006] An embodiment of the present invention provides a motor vibration detection method, comprising:

[0007] Fixing the air conditioner indoor unit on the test platform, fixing the fiber grating sensor on the motor of the air conditioner indoor unit, connecting the fiber grating sensor to a demodulator, and connecting the demodulator to a processing terminal;

[0008] Starting the air conditioner indoor unit to operate the motor;

[0009] Using the fiber grating sensor to collect the vibration signal generated by the motor vibration, and transmitting the vibration signal to the demodulator;

[0010] Demodulating the vibration signal using the demodulator to obtain a center wavelength drift, and sending the result to the processing terminal;

[0011] The processing terminal is used to calculate the center wavelength drift, obtain the acceleration of the vibration signal and display it.

[0012] Furthermore, the fiber grating sensor is manufactured in the following manner:

[0013] Obtaining the vibration frequency and vibration amplitude of the motor;

[0014] Establishing a symmetrical design model of the fiber grating sensor according to the vibration frequency and vibration amplitude of the motor;

[0015] Simulating the sensing characteristics of the fiber Bragg grating sensor in different vibration directions based on the symmetrical design model, and determining the corresponding material properties and dimensional parameters through simulation and numerical analysis;

[0016] The fiber grating sensor is obtained by processing according to the material properties and size parameters.

[0017] Furthermore, before the steps of fixing the air conditioner indoor unit on the test platform, fixing the fiber grating sensor on the motor of the air conditioner indoor unit, connecting the fiber grating sensor to a demodulator, and connecting the demodulator to a processing terminal, the steps include:

[0018] Fixing the vibration table on the test platform, fixing the fiber Bragg grating sensor and the verification sensor on the vibration table, connecting the fiber Bragg grating sensor to the demodulator, and connecting the demodulator to the processing terminal; connecting the verification sensor to the acceleration collector, and connecting the acceleration collector to the verification terminal; wherein the vibration table is connected with a power amplifier and a signal generator in sequence; wherein the fiber Bragg grating sensor, the demodulator and the processing terminal constitute a system to be tested, and the verification sensor, the acceleration collector and the verification terminal constitute a verification system;

[0019] Starting the signal generator to generate a test signal, and amplifying the test signal through the power amplifier, so that the vibration table generates corresponding vibration;

[0020] Acquiring the system to be tested to obtain the data to be tested, and acquiring the verification system to obtain the verification data;

[0021] The data to be tested is verified using the verification data to obtain a verification result for the performance indicator of the system to be tested.

[0022] Furthermore, the verification sensor is a piezoelectric sensor or a piezoresistive sensor.

[0023] Furthermore, the performance indicators include natural frequency, sensitivity and lateral interference resistance.

[0024] Further, starting the signal generator to generate a test signal includes:

[0025] The frequency and type of the test signal generated by the signal generator are adjusted so that the frequency and type of the test signal are consistent with the frequency and type of the vibration table.

[0026] Furthermore, the fiber grating sensor is connected to the demodulator via a jumper.

[0027] Furthermore, the motor vibration detection method further includes:

[0028] Fixing a verification sensor on the motor, connecting the verification sensor to an acceleration collector, and connecting the acceleration collector to a verification terminal;

[0029] Using the verification sensor to collect the vibration signal generated by the motor vibration, and transmitting the vibration signal to the acceleration collector;

[0030] Using the acceleration collector to collect the vibration signal to obtain vibration data, and sending the data to the verification terminal;

[0031] Calculating the vibration data using the verification terminal to obtain and display the acceleration of the vibration signal;

[0032] The acceleration obtained by the verification terminal is used to verify the acceleration obtained by the processing terminal to obtain a verification result for the performance indicator of the system to be tested.

[0033] Further, the demodulating the vibration signal by the demodulator to obtain the center wavelength drift and sending it to the processing terminal includes:

[0034] Initializing the demodulator to calibrate the wavelength range of the broadband light source;

[0035] Using a digital filtering algorithm to adjust the output power of the broadband light source;

[0036] The broadband light source is transmitted to the fiber grating sensor, and the attenuation of the optical signal during the transmission process is monitored to obtain a reflected light wave.

[0037] Furthermore, the demodulating the vibration signal using the demodulator to obtain the center wavelength drift and sending it to the processing terminal also includes:

[0038] Calibrate the demodulation channel of the demodulator;

[0039] receiving the reflected light wave based on the demodulation channel and converting the reflected light wave into a digital signal;

[0040] Analyzing the physical quantity information in the digital signal to extract characteristic parameters of the reflected light wave;

[0041] The characteristic parameters of the reflected light wave are identified by using a demodulation algorithm, and the central wavelength drift is extracted.

[0042] The embodiment of the present invention provides a motor vibration detection method, including fixing an air conditioner indoor unit on a test platform, fixing a fiber grating sensor on the motor of the air conditioner indoor unit, connecting the fiber grating sensor to a demodulator, and connecting the demodulator to a processing terminal; starting the air conditioner indoor unit to make the motor run; using the fiber grating sensor to collect the vibration signal generated by the motor vibration, and transmitting the vibration signal to the demodulator; using the demodulator to demodulate the vibration signal to obtain the center wavelength drift, and send it to the processing terminal; using the processing terminal to calculate the center wavelength drift, obtain the acceleration of the vibration signal and display it. The present invention detects the vibration signal by using a fiber grating sensor in conjunction with a demodulator. The fiber grating sensor has the ability to resist electromagnetic interference, can achieve more accurate vibration detection, and can be tested in real time without relying on historical parameters. In this way, the factory test effect of the air conditioner indoor unit motor is effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying any creative work.

[0044] Figure 1 A schematic diagram of a motor vibration detection method provided by an embodiment of the present invention Figure 1 ;

[0045] Figure 2 A test diagram of a motor vibration detection method provided by an embodiment of the present invention Figure 1 ;

[0046] Figure 3 A test diagram of a motor vibration detection method provided by an embodiment of the present invention Figure 2 ;

[0047] Figure 4 A schematic diagram of a motor vibration detection method provided by an embodiment of the present invention Figure 2 .

[0048] Description of the symbols in the figure:

[0049] 10. Air conditioner indoor unit; 11. Motor; 20. Test platform; 30. Fiber Bragg grating sensor; 40. Demodulator; 50. Processing terminal; 60. Vibration table; 61. Power amplifier; 62. Signal generator; 70. Verification sensor; 80. Acceleration collector; 90. Verification terminal. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0052] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0053] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0054] Combination Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a motor vibration detection method, comprising the following steps S101-S105:

[0055] S101, fixing the air conditioner indoor unit 10 on the test platform 20, fixing the fiber grating sensor 30 on the motor 11 of the air conditioner indoor unit 10, connecting the fiber grating sensor 30 to the demodulator 40, and connecting the demodulator 40 to the processing terminal 50;

[0056] S102, start the air conditioner indoor unit 10 to make the motor 11 run;

[0057] S103, using the fiber grating sensor 30 to collect the vibration signal generated by the vibration of the motor 11, and transmitting the vibration signal to the demodulator 40;

[0058] S104, using the demodulator 40 to demodulate the vibration signal to obtain a center wavelength drift, and sending the result to the processing terminal 50;

[0059] S105 , using the processing terminal 50 to calculate the central wavelength drift, obtain the acceleration of the vibration signal and display it.

[0060] In this embodiment, in step S101, the air conditioner indoor unit 10 is fixed on the test platform 20 (needs to be fixed horizontally, that is, the vibration direction is consistent with the measurement direction), and the air conditioner indoor unit 10 is fixedly connected to the test platform 20 (the test platform 20 can be a cast iron platform, the same below) through connectors (such as bolts and nuts) to ensure stability during testing. The fiber grating sensor 30 is installed on the motor 11 of the air conditioner indoor unit 10, and appropriate fixing means (such as AB glue or other bonding methods) are used to ensure that the fiber grating sensor 30 is in contact with the surface of the motor 11. The fiber grating sensor 30 is connected to the demodulator 40, and the demodulator 40 is further connected to the processing terminal 50 to provide a complete test chain for subsequent signal transmission and processing.

[0061] In step S102, the air conditioner indoor unit 10 is started to make the motor 11 enter a normal operation state. During the operation, the operation of the motor 11 will generate a vibration signal for collection and analysis in subsequent steps.

[0062] In step S103 , the fiber grating sensor 30 collects vibration signals generated during the operation of the motor 11 in real time, and transmits the collected vibration signals to the demodulator 40 . The fiber grating sensor 30 can capture vibration changes during the operation of the motor 11 .

[0063] In step S104, the demodulator 40 performs spectral demodulation on the received vibration signal to obtain the center wavelength drift of the signal, and sends the center wavelength drift as a characteristic parameter to the processing terminal 50 to provide basic data for subsequent calculations.

[0064] In step S105, after receiving the center wavelength drift amount transmitted by the demodulator 40, the processing terminal 50 analyzes and calculates the center wavelength drift amount using a preset calculation model, and converts it into the acceleration of the vibration signal. The acceleration is derived from the theoretical relationship between the center wavelength drift amount and the acceleration. Finally, the processing terminal 50 displays the calculated acceleration on the screen of the processing terminal 50, providing intuitive vibration signal data for the operator.

[0065] In one embodiment, the fiber grating sensor 30 is manufactured in the following manner:

[0066] Obtaining the vibration frequency and vibration amplitude of the motor 11;

[0067] A symmetrical design model of the fiber grating sensor 30 is established according to the vibration frequency and vibration amplitude of the motor 11;

[0068] Simulating the sensing characteristics of the fiber grating sensor 30 in different vibration directions based on the symmetrical design model, and determining the corresponding material properties and dimensional parameters through simulation and numerical analysis;

[0069] The fiber grating sensor 30 is obtained by processing according to the material properties and size parameters.

[0070] In this embodiment, first, the vibration frequency and vibration amplitude of the motor 11 are obtained, and the vibration frequency and vibration amplitude of the motor 11 are obtained by analyzing the operating characteristics of the motor 11. Based on the symmetrical design model, it is ensured that the fiber grating sensor 30 has a balanced sensing ability in different vibration directions, thereby enhancing its anti-interference ability and measurement accuracy. Based on the symmetrical design model, the sensing characteristics of the fiber grating sensor 30 in different vibration directions are simulated. Finite element simulation tools can be used to simulate and analyze the sensing characteristics of the fiber grating sensor 30 to predict its sensitivity and anti-interference ability in different vibration directions. Through continuous optimization of design and numerical analysis, the material properties and dimensional parameters of the fiber grating sensor 30 are determined, so that the fiber grating sensor 30 can achieve better performance indicators under actual working conditions.

[0071] Further, the fiber Bragg grating sensor 30 is obtained by processing according to the material properties and size parameters. According to the optimized design scheme, suitable materials (such as high-performance optical fiber materials and strain-sensitive coatings) are selected, and precision processing technology is used to manufacture the fiber Bragg grating sensor 30. After processing, the fiber Bragg grating sensor 30 needs to undergo performance calibration experiments to verify whether its vibration sensing characteristics meet the design requirements.

[0072] Combination Figure 3 As shown, in one embodiment, before the steps of fixing the air conditioner indoor unit 10 on the test platform 20, fixing the fiber grating sensor 30 on the motor 11 of the air conditioner indoor unit 10, connecting the fiber grating sensor 30 to the demodulator 40, and connecting the demodulator 40 to the processing terminal 50, the steps include:

[0073] Fix the excitation table 60 on the test platform 20, fix the fiber Bragg grating sensor 30 and the verification sensor 70 on the excitation table 60 (both need to be kept horizontal, that is, the vibration measurement direction is consistent with the excitation direction), and connect the fiber Bragg grating sensor 30 to the demodulator 40, and connect the demodulator 40 to the processing terminal 50; connect the verification sensor 70 to the acceleration collector 80, and connect the acceleration collector 80 to the verification terminal 90; wherein the excitation table 60 is connected with a power amplifier 61 and a signal generator 62 in sequence; wherein the fiber Bragg grating sensor 30, the demodulator 40 and the processing terminal 50 constitute a system to be tested, and the verification sensor 70, the acceleration collector 80 and the verification terminal 90 constitute a verification system;

[0074] The start signal generator 62 generates a test signal, and amplifies it through the power amplifier 61, so that the vibration table 60 generates corresponding vibration;

[0075] Acquiring the system to be tested to obtain the data to be tested, and acquiring the verification system to obtain the verification data;

[0076] The data to be tested is verified using the verification data to obtain a verification result for the performance indicator of the system to be tested.

[0077] In this embodiment, in order to ensure that the performance indicators of the system to be tested in the motor vibration detection method meet the expected requirements, before the steps of fixing the air conditioner indoor unit 10 and installing the fiber grating sensor 30 are performed, the performance of the system to be tested needs to be verified, which is specifically as follows: fix the vibration table 60 on the test platform 20 to ensure its stability to avoid the vibration of the vibration table 60 during the experiment affecting the test results. At the same time, the fiber grating sensor 30 and the verification sensor 70 are respectively installed on the surface of the vibration table 60, and an adhesive or other fixing method is used to ensure that the two sensors are firmly attached to the surface of the vibration table 60. Connect the fiber grating sensor 30 to the demodulator 40, and connect the demodulator 40 to the processing terminal 50 to form a system to be tested. The verification sensor 70 is connected to the acceleration collector 80 via a cable, and is further connected to the verification terminal 90 to form a verification system.

[0078] Furthermore, the excitation table 60 is connected to the power amplifier 61, and the power amplifier 61 is connected to the signal generator 62 to form an excitation control link. The signal generator 62 is used to generate test signals of different frequencies and amplitudes, which are amplified by the power amplifier 61 to drive the excitation table 60 to generate corresponding vibrations. Start the signal generator 62, set the frequency, amplitude and waveform (such as sine wave, sawtooth wave or pulse wave) of the signal according to the experimental requirements, and the signal is amplified by the power amplifier 61 and transmitted to the excitation table 60. In the process of the excitation table 60 generating vibrations, the fiber grating sensor 30 collects the vibration signal and transmits the signal to the demodulator 40 for demodulation, and the processing terminal 50 records and analyzes the demodulated data to obtain the vibration data of the system to be tested. The verification sensor 70 synchronously collects the vibration signal, transmits it to the verification terminal 90 through the acceleration collector 80, and records and generates verification data.

[0079] Furthermore, the vibration data of the system to be tested is compared with the vibration data of the verification system. The verification data obtained by the verification system is used as a reference benchmark to perform verification analysis on the vibration data of the system to be tested, thereby evaluating the performance indicators of the system to be tested and obtaining verification results.

[0080] In one embodiment, the verification sensor 70 is a piezoelectric sensor or a piezoresistive sensor.

[0081] In this embodiment, the verification sensor 70 can be a piezoelectric sensor or a piezoresistive sensor to meet the needs of collecting vibration signals. A piezoelectric sensor is a sensor based on the piezoelectric effect. When it is subjected to mechanical vibration, the internal piezoelectric material will generate a charge signal proportional to the vibration acceleration. The piezoelectric sensor has high sensitivity and a wide frequency response range, and is suitable for capturing tiny vibration signals generated by the excitation table 60. The piezoresistive sensor responds to the vibration signal through a change in resistance. When the piezoresistive element is subjected to stress caused by vibration, its resistance value will change, and the acceleration of the vibration signal can be indirectly measured by detecting the change in resistance. The piezoresistive sensor has good linearity and low power consumption, is suitable for collecting vibration signals in lower frequency bands, and has a simple structure and is easy to integrate and install. According to the actual experimental requirements and the characteristics of the vibration signal, the selection of the verification sensor 70 can be flexibly adjusted between the piezoelectric sensor and the piezoresistive sensor. For example, when the experiment requires high-frequency vibration data verification, a piezoelectric sensor can be preferred; while for low-frequency vibration signal verification, a piezoresistive sensor can be selected to ensure the accuracy and stability of the detection. Regardless of the type of verification sensor 70, the acceleration collector 80 is required to convert the collected vibration signal into a digital signal that can be processed by the verification terminal 90. During the test, the verification sensor and the system to be tested operate synchronously, and the vibration signal data collected by the verification sensor will be used as a reference benchmark to evaluate the performance indicators of the fiber grating sensor 30 and its system to be tested.

[0082] In one embodiment, the performance indicators include natural frequency, sensitivity and lateral interference immunity.

[0083] In this embodiment, the natural frequency represents the frequency range that the fiber Bragg grating sensor 30 can accurately sense in the vibration response. Through theoretical modeling and simulation analysis of the fiber Bragg grating sensor 30, combined with the test data of the verification system in an actual vibration environment, it is evaluated whether the natural frequency of the fiber Bragg grating sensor 30 matches the main frequency range of the motor 11 vibration. If there is a deviation, it can be optimized by adjusting the material properties or structural parameters of the fiber Bragg grating sensor 30.

[0084] Sensitivity can measure the intensity of the fiber Bragg grating sensor 30's response to the vibration signal. The center wavelength drift amount collected by the fiber Bragg grating sensor 30 of the system under test needs to have a good linear relationship with the vibration acceleration. In the verification stage, by comparing and verifying the amplitude of the vibration signal collected by the fiber Bragg grating sensor 30 with the test data output by the system under test, it is evaluated whether the sensitivity of the fiber Bragg grating sensor 30 meets the design requirements. If the sensitivity is insufficient, the signal of low-amplitude vibration may be ignored, thereby affecting the detection accuracy.

[0085] The lateral anti-interference degree can be used to indicate the index of the system under test to maintain the measurement stability in a complex vibration environment. Since there may be multi-directional vibration interference during the operation of the motor 11, the fiber grating sensor 30 needs to have good anti-interference performance to ensure that its response to the target vibration signal is not affected by the lateral interference. In the performance verification, multi-directional vibration is generated by the excitation table 60, and the data of the verification sensor 70 and the fiber grating sensor 30 are collected and analyzed, and the signal error of the system under lateral vibration is compared and analyzed to evaluate its anti-interference ability.

[0086] In one embodiment, the start signal generator 62 generates a test signal, including:

[0087] The frequency and type of the test signal generated by the signal generator 62 are adjusted to make the frequency and type of the test signal consistent with the frequency and type of the vibration table 60 .

[0088] In this embodiment, the initial parameters of the signal generator 62, including the frequency range and waveform type, are set according to the experimental requirements. The signal generator 62 can generate various types of signals, such as sine waves, sawtooth waves, square waves, pulse waves, and random noise signals, to meet the vibration simulation requirements of different experimental scenarios. The frequency of the test signal generated by the signal generator 62 is adjusted to ensure that the frequency of the test signal is consistent with the natural frequency range of the vibration table 60. In this step, the output frequency of the signal generator 62 can be adjusted by a knob or digital input so that the vibration table 60 can generate stable vibrations at a specific frequency. Adjust the type of test signal generated by the signal generator 62 to match the vibration waveform required for the experiment. For example, when it is necessary to simulate periodic vibration, a sine wave signal can be selected; when the test needs to simulate transient impact vibration, a pulse wave signal can be selected.

[0089] In one embodiment, the fiber grating sensor 30 is connected to the demodulator 40 via a jumper.

[0090] In this embodiment, a matching fiber jumper is selected according to the connection interface requirements of the fiber grating sensor 30 and the demodulator 40. The jumper needs to have excellent optical performance and mechanical stability to reduce loss and interference during signal transmission. One end of the jumper is connected to the optical fiber output end of the fiber grating sensor 30, and the grating in the fiber grating sensor 30 can be fused with the jumper by a fusion splicer. Before fusion, the end faces of the grating and the jumper need to be repaired by a fiber optic cutter and sprayed with alcohol for cleaning. The other end of the jumper is connected to the input port of the demodulator 40 to ensure that the interface is firmly connected and meets the standard requirements for optical fiber connection. The demodulator 40 usually comes with an interface protection device to reduce the interference of the external environment on the optical signal.

[0091] In one embodiment, the motor vibration detection method further includes:

[0092] Fixing the verification sensor 70 on the motor 11, connecting the verification sensor 70 to the acceleration collector 80, and connecting the acceleration collector 80 to the verification terminal 90;

[0093] The verification sensor 70 is used to collect the vibration signal generated by the vibration of the motor 11, and the vibration signal is transmitted to the acceleration collector 80;

[0094] The vibration signal is collected by the acceleration collector 80 to obtain vibration data, and the data is sent to the verification terminal 90;

[0095] Calculating the vibration data using the verification terminal 90 to obtain and display the acceleration of the vibration signal;

[0096] The acceleration obtained by the verification terminal 90 is used to verify the acceleration obtained by the processing terminal 50 to obtain a verification result for the performance index of the system to be tested.

[0097] In this embodiment, the verification sensor can also be used to verify the performance index of the system to be tested, as follows: the verification sensor 70 is fixed on the motor 11, and the verification sensor 70 is ensured to be fastened to the surface of the motor 11 by bonding or mechanical fixing to accurately capture the vibration signal when the motor is running. The verification sensor 70 is connected to the acceleration collector 80 through a cable, and the acceleration collector 80 is further connected to the verification terminal 90 to build a verification system. During the operation of the motor 11, the verification sensor 70 collects the vibration signal generated by its vibration in real time. The verification sensor 70 converts the vibration signal into a voltage signal proportional to the acceleration and transmits it to the acceleration collector 80 for processing. The acceleration collector 80 collects data on the received vibration signal to obtain vibration data. Subsequently, the acceleration collector 80 transmits the vibration data to the verification terminal 90 for further calculation and analysis. After receiving the vibration data from the acceleration collector 80, the verification terminal 90 uses the built-in calculation model to parse and process the vibration data. The verification terminal 90 calculates the acceleration of the vibration signal according to the characteristic curve of the verification sensor 70, and displays the acceleration result in real time on the display screen of the verification terminal 90 for the operator's reference. The acceleration obtained by the verification terminal 90 is compared and analyzed with the acceleration output by the processing terminal 50. Based on the verification results, the performance of the system under test is comprehensively evaluated.

[0098] In one embodiment, the demodulating the vibration signal by using the demodulator 40 to obtain the center wavelength drift and sending it to the processing terminal 50 includes:

[0099] Initializing the demodulator 40 to calibrate the wavelength range of the broadband light source;

[0100] Using a digital filtering algorithm to adjust the output power of the broadband light source;

[0101] The broadband light source is transmitted to the fiber grating sensor 30, and the attenuation of the optical signal during the transmission process is monitored to obtain a reflected light wave.

[0102] In this embodiment, the demodulator 40 is initialized and the wavelength range of the broadband light source is calibrated. After the demodulator 40 is started, the built-in broadband light source is first initialized to ensure that the wavelength range of the light source covers the working range of the fiber grating sensor 30. The wavelength range and output stability of the broadband light source are accurately adjusted through the calibration procedure to ensure that the output optical signal can be accurately transmitted to the fiber grating sensor. The output power of the broadband light source is optimized and adjusted using a digital filtering algorithm. The output power of the broadband light source is adjustable within a certain range. The optical power signal output by the light source is smoothed by a digital filtering algorithm to eliminate the high-frequency noise component in the optical signal, while ensuring the uniformity of the output power, providing a stable optical input for subsequent signal transmission. The optical signal of the broadband light source is transmitted to the fiber grating sensor 30, and the attenuation of the optical signal during the transmission process is monitored in real time. In the process of transmitting the optical signal output by the broadband light source to the fiber grating sensor 30, the optical signal intensity in the transmission path is detected by the built-in optical monitoring module of the demodulator 40 to capture the signal attenuation that may be caused by the characteristics of the transmission medium or the environmental influence. The signal loss in the optical signal transmission path is adjusted. After the optical signal attenuation is detected, the optical power output and signal processing parameters of the demodulator 40 are automatically adjusted to compensate for the signal strength reduction caused by the optical fiber medium or connector loss, ensuring that the reflected light wave of the fiber grating sensor 30 has sufficient signal strength. The reflected light wave of the fiber grating sensor 30 is collected and analyzed. The fiber grating sensor 30 modulates the central wavelength of the reflected light wave according to the change of the vibration signal. After receiving the reflected light wave, the demodulator 40 extracts the drift of the central wavelength through the high-precision spectrum analysis module, and outputs the drift as the key parameter of the vibration signal to the processing terminal 50.

[0103] In one embodiment, the demodulating the vibration signal by using the demodulator 40 to obtain the center wavelength drift and sending it to the processing terminal 50 also includes:

[0104] Calibrate the demodulation channel of the demodulator 40;

[0105] receiving the reflected light wave based on the demodulation channel and converting the reflected light wave into a digital signal;

[0106] Analyzing the physical quantity information in the digital signal to extract characteristic parameters of the reflected light wave;

[0107] The characteristic parameters of the reflected light wave are identified by using a demodulation algorithm, and the central wavelength drift is extracted.

[0108] In this embodiment, the demodulation channel of the demodulator 40 is calibrated. After the demodulator 40 is started, the demodulation channel inside it is initialized and calibrated to ensure that the sensitivity and response speed of each channel are consistent. During the calibration process, each demodulation channel is input through a standard optical signal, the accuracy and stability of the output signal are detected, and the channel parameters are adjusted to achieve the best demodulation effect. The reflected light wave of the fiber grating sensor 30 is received based on the calibrated demodulation channel. The reflected light wave is transmitted to the input port of the demodulator 40 through an optical fiber jumper. After being received by the demodulation channel, the reflected light wave is converted into a digital signal using a photoelectric conversion module to ensure that the signal maintains integrity and operability in subsequent processing links. The physical quantity information in the digital signal is analyzed to extract the characteristic parameters of the reflected light wave. The demodulator performs real-time analysis on the digital signal after photoelectric conversion, detects the change of the central wavelength in the light wave signal through spectral demodulation technology, and extracts the characteristic parameters related to the vibration signal. These characteristic parameters include but are not limited to wavelength offset, optical power intensity and signal noise level, providing detailed data support for subsequent calculations. The characteristic parameters of the reflected light wave are identified and analyzed using a demodulation algorithm. The demodulator 40 has a built-in high-precision demodulation algorithm, which extracts the center wavelength drift by analyzing the relationship between the characteristic parameters and the force change of the sensor. The demodulation algorithm needs to comprehensively consider the characteristic curve of the fiber grating sensor 30 and the system noise compensation to ensure the accuracy and robustness of the calculation results. Finally, the extracted center wavelength drift is sent to the processing terminal 50. After receiving the center wavelength drift, the processing terminal 50 converts it into the acceleration value of the vibration signal through a preset vibration model, and uses it for further analysis and display.

[0109] Combination Figure 4 As shown above, in summary, the present invention proposes a new vibration test method for the indoor motor of an air conditioner. Compared with most motor factory vibration test methods, this method is more accurate, can not only avoid electromagnetic interference, but also has a certain lateral anti-interference ability. The specific implementation steps are as follows:

[0110] Step 1: For the motor 11 that needs vibration testing, understand the basic parameters to determine the vibration frequency and vibration amplitude of the motor 11. According to the vibration characteristics of the motor 11, the natural frequency, sensitivity and range of the fiber grating sensor 30 are inferred.

[0111] Step 2: Design a symmetrical design model to enable it to have a certain lateral anti-interference ability. Through the mechanical model of the fiber Bragg grating sensor 30, a theoretical analysis is conducted to understand its working principle and performance. Using numerical analysis methods, the material properties and dimensional parameters of each structure of the fiber Bragg grating sensor 30 are determined to ensure that it meets various index requirements. Use three-dimensional modeling software to build a symmetrical design model, import the symmetrical design model into ANSYS software for simulation analysis, and verify the feasibility of the theoretical symmetrical design model through simulation results. Finally, according to the design and simulation results, the fiber Bragg grating sensor 30 is processed and assembled.

[0112] Step 3: Use the vibration table 60 to fix the cast iron platform (i.e., the test platform 20) with bolts and nuts to protect the vibration table 60 and the ground. The signal generator 62 and the power amplifier 61 jointly control the vibration frequency, amplitude, and type of the vibration table 60. Adjust the knobs and buttons of the signal generator 62 to set the frequency and type of the signal (such as sine, sawtooth, pulse, noise, etc. waveforms). The signal is amplified by the power amplifier 61 to drive the vibration table 60 to generate corresponding vibrations. The fiber grating sensor 30 and the verification sensor 70 are fixed on the surface of the vibration table 60 by AB glue. Connect with the demodulator 40 through a jumper, and the demodulator 40 is used to read the center wavelength drift. Transmit the vibration signal to the LMS (acceleration collector 80). The demodulator 40 demodulates the center wavelength drift and transmits the data to PC-1 (processing terminal 50) for display and analysis. The acceleration collector 80 collects data and transmits it to PC-2 (verification terminal 90) for display.

[0113] Step 4: In the actual application process, a fixing hole is drilled on the air conditioner indoor unit 10, and it is fixedly connected to the test platform 20 by bolts and nuts. A platform is built on the upper surface of the motor 11, and the fiber grating sensor 30 and the verification sensor 70 are fixed on the motor 11 by AB glue. The fiber grating sensor 30 is connected to the demodulator 40 through a jumper, and the verification sensor 70 is connected to the acceleration collector 80. The demodulator 40 and the acceleration collector 80 are respectively connected to PC-1 (processing terminal 50) and PC-2 (verification terminal 90). When the motor 11 is running, the motor 11 generates vibration. The vibration signal is transmitted to the fiber grating sensor 30, and the fiber grating sensor 30 reflects light of a specific wavelength. The reflected light is transmitted back to the demodulator 40, and the demodulator 40 demodulates to obtain the center wavelength drift. Through theoretical analysis, the relationship between the center wavelength drift and the acceleration is established, and the acceleration is calculated and displayed on PC-1. It should be noted that the vibration signal is transmitted to the verification sensor 70, and the acceleration can be directly obtained. The data is displayed on PC-2 without additional integration. By comparing the accelerations measured by the two sensors, it can be found that the measurement result of the fiber grating sensor 30 is more accurate (due to its anti-electromagnetic interference capability), which proves that the fiber grating sensor 30 is more effective in measuring the vibration of the motor 11.

[0114] In addition, according to the application requirements of the motor 11, the structure of the fiber Bragg grating sensor 30 can be appropriately improved to achieve temperature compensation, for example, a dual grating compensation method can be used to achieve temperature compensation. Temperature compensation can avoid the interference of ambient temperature changes on vibration measurement and ensure that the measurement results of the fiber Bragg grating sensor 30 are not affected by temperature.

[0115] The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of this application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of this application.

[0116] It should also be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

Claims

1. A motor vibration detection method, characterized in that: include: Fixing the air conditioner indoor unit on the test platform, fixing the fiber grating sensor on the motor of the air conditioner indoor unit, connecting the fiber grating sensor to a demodulator, and connecting the demodulator to a processing terminal; Starting the air conditioner indoor unit to operate the motor; Using the fiber grating sensor to collect the vibration signal generated by the motor vibration, and transmitting the vibration signal to the demodulator; Demodulating the vibration signal using the demodulator to obtain a center wavelength drift, and sending the result to the processing terminal; The processing terminal is used to calculate the center wavelength drift, obtain the acceleration of the vibration signal and display it.

2. The motor vibration detection method according to claim 1, characterized in that: The fiber grating sensor is manufactured in the following manner: Obtaining the vibration frequency and vibration amplitude of the motor; Establishing a symmetrical design model of the fiber grating sensor according to the vibration frequency and vibration amplitude of the motor; Simulating the sensing characteristics of the fiber grating sensor in different vibration directions based on the symmetrical design model, and determining the corresponding material properties and dimensional parameters through simulation and numerical analysis structure; The fiber grating sensor is obtained by processing according to the material properties and size parameters.

3. The motor vibration detection method according to claim 1, characterized in that: Before the steps of fixing the air conditioner indoor unit on the test platform, fixing the fiber grating sensor on the motor of the air conditioner indoor unit, connecting the fiber grating sensor to a demodulator, and connecting the demodulator to a processing terminal, the method includes: Fixing the vibration table on the test platform, fixing the fiber Bragg grating sensor and the verification sensor on the vibration table, connecting the fiber Bragg grating sensor to the demodulator, and connecting the demodulator to the processing terminal; connecting the verification sensor to the acceleration collector, and connecting the acceleration collector to the verification terminal; wherein the vibration table is connected with a power amplifier and a signal generator in sequence; wherein the fiber Bragg grating sensor, the demodulator and the processing terminal constitute a system to be tested, and the verification sensor, the acceleration collector and the verification terminal constitute a verification system; Starting the signal generator to generate a test signal, and amplifying the test signal through the power amplifier, so that the vibration table generates corresponding vibration; Acquiring the system to be tested to obtain the data to be tested, and acquiring the verification system to obtain the verification data; The data to be tested is verified using the verification data to obtain a verification result for the performance indicator of the system to be tested.

4. The motor vibration detection method according to claim 3, characterized in that: The verification sensor is a piezoelectric sensor or a piezoresistive sensor.

5. The motor vibration detection method according to claim 3, characterized in that: The performance indicators include natural frequency, sensitivity and lateral interference immunity.

6. The motor vibration detection method according to claim 3, characterized in that: The step of starting the signal generator to generate a test signal comprises: The frequency and type of the test signal generated by the signal generator are adjusted so that the frequency and type of the test signal are consistent with the frequency and type of the vibration table.

7. The motor vibration detection method according to claim 1, characterized in that: The fiber grating sensor is connected to the demodulator via a jumper.

8. The motor vibration detection method according to claim 1, characterized in that: Also includes: Fixing a verification sensor on the motor, connecting the verification sensor to an acceleration collector, and connecting the acceleration collector to a verification terminal; Using the verification sensor to collect the vibration signal generated by the motor vibration, and transmitting the vibration signal to the acceleration collector; Using the acceleration collector to collect the vibration signal to obtain vibration data, and sending the data to the verification terminal; Calculating the vibration data using the verification terminal to obtain and display the acceleration of the vibration signal; The acceleration obtained by the verification terminal is used to verify the acceleration obtained by the processing terminal to obtain a verification result for the performance indicator of the system to be tested.

9. The motor vibration detection method according to claim 1, characterized in that: The demodulating the vibration signal by the demodulator to obtain the center wavelength drift and sending the center wavelength drift to the processing terminal comprises: Initializing the demodulator to calibrate the wavelength range of the broadband light source; Using a digital filtering algorithm to adjust the output power of the broadband light source; The broadband light source is transmitted to the fiber grating sensor, and the attenuation of the optical signal during the transmission process is monitored to obtain a reflected light wave.

10. The motor vibration detection method according to claim 9, characterized in that: The method of using the demodulator to demodulate the vibration signal to obtain the center wavelength drift and sending the center wavelength drift to the processing terminal further includes: Calibrate the demodulation channel of the demodulator; receiving the reflected light wave based on the demodulation channel and converting the reflected light wave into a digital signal; Analyzing the physical quantity information in the digital signal to extract characteristic parameters of the reflected light wave; The characteristic parameters of the reflected light wave are identified by using a demodulation algorithm, and the central wavelength drift is extracted.

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