Bearing vibration detection system based on white light LED

Abstract

The invention belongs to the field of bearing state monitoring, and particularly relates to a bearing vibration detection system based on a white light LED. The bearing vibration detection system comprises a vibration sensor used for collecting vibration signals generated by a bearing, and a signal conditioning circuit used for processing the vibration signals collected by the vibration sensor into digital signals. The white light LED transmitting module is used for outputting the vibration signal in the digital signal form obtained by the signal conditioning circuit through a white light LED signal; the white light LED receiving module is used for receiving a white light LED signal transmitted by the white light LED transmitting module; and an electric signal obtained by the white light LED receiving module is used for extracting vibration information of the bearing. Due to the fact that the white light LED signals do not affect operation of the bearing, the white light LED signals are basically not limited under the interference working conditions of high temperature, high voltage, strong electromagnetic interference and the like where the bearing is frequently located, the influence on transmitted bearing vibration information is small, the situation that the vibration information cannot be transmitted rarely occurs, and the effect of strong anti-interference performance is achieved.

Description

Technical Field

[0001] The present invention belongs to the field of bearing condition monitoring, and particularly relates to a bearing vibration detection system based on white light LEDs. Background Art

[0002] Bearings are crucial components in mechanical equipment, and their performance directly affects the stable operation and lifespan of the equipment. However, bearings are affected by various factors during long-term operation, which may lead to defects or even failures. Therefore, it is of great significance to timely and effectively monitor the operating state of bearings and predict possible defects to improve the reliability of the equipment and reduce maintenance costs.

[0003] Traditional methods for detecting bearing vibration signals usually directly connect vibration sensors through wires. Although they can meet the detection requirements to a certain extent, there are also some limitations. For example, in some special environments, such as high temperature, high pressure, and strong electromagnetic interference, the signals transmitted through wires are easily interfered, resulting in a decrease in the signal-to-noise ratio of the acquired vibration data or even distortion, making it impossible to accurately evaluate the bearing state subsequently. Adding enhanced cable shielding and installing hardware filters, although simple to implement and low in cost, are only suitable for temporary monitoring of non-critical bearings or scenarios with weak interference due to limited anti-interference ability and poor environmental adaptability. This method is simple but not efficient. The wireless sensor network combined with the adaptive noise reduction algorithm and edge computing can significantly solve the problems of signal acquisition and diagnosis in extreme environments through high-temperature-resistant sensors, ultra-wideband anti-interference transmission, and intelligent signal processing, and is suitable for long-term reliable monitoring of high-value critical bearings, but faces challenges of complex technology and high cost. Although the effect is better, it is more complex. Summary of the Invention

[0004] The purpose of the present invention is to provide a bearing vibration detection system based on white light LEDs to solve the problems in the prior art that the data obtained through communication by the bearing vibration signal detection device is inaccurate, not sensitive enough to the bearing defect state, or the data collected by the bearing vibration signal detection device through communication cannot be obtained through communication.

[0005] To achieve the above purpose, the present invention provides a bearing vibration detection system based on white light LEDs, including: a vibration sensor for collecting vibration signals generated by the bearing, a signal conditioning circuit for processing the vibration signals collected by the vibration sensor into digital signal form, a white light LED emission module for outputting the vibration signals in digital signal form obtained by the signal conditioning circuit through white light LED signals; and a white light LED receiving module for receiving the white light LED signals emitted by the white light LED emission module; the electrical signals obtained by the white light LED receiving module are used to extract the vibration information of the bearing.

[0006] Further, the white light LED emission module includes a white light LED and a drive circuit; the drive circuit is used to provide current drive for the white light LED, so as to output the vibration signal in the form of a digital signal obtained by the signal conditioning circuit as a white light LED signal through the white light LED.

[0007] Further, the white light LED reception module includes a photoelectric conversion device and a second amplification circuit;

[0008] The photoelectric conversion device is used to receive the white light LED signal emitted by the white light LED emission module and convert the received white light LED signal into an electrical signal; the second amplification circuit is used to amplify the electrical signal converted by the photoelectric conversion device.

[0009] Further, a signal processing module is also included; the signal processing module includes an analysis sub-module; the analysis sub-module is used to analyze the electrical signal obtained by the white light LED reception module, and the analysis process includes:

[0010] First, the electrical signal obtained by the white light LED reception module is converted into a signal in a frequency band containing the frequency corresponding to the bearing fault to be detected through band-pass filtering, then the signal in the frequency band is decomposed into each IMF component, the envelope spectrum of each IMF component is calculated, and then the defect frequency factors corresponding to the envelope spectra of each IMF component of the bearing component to be detected are calculated. Whether the bearing component has a defect is judged by judging whether the defect frequency factor of the bearing component exceeds the corresponding bearing component fault threshold;

[0011] The calculation method of the defect frequency factor of the bearing component corresponding to the envelope spectrum of each IMF component includes:

[0012] Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the first set range of frequencies containing the theoretical defect characteristic frequency of the bearing component as the first-harmonic defect energy characteristic; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the first-harmonic set range of frequencies corresponding to the theoretical defect characteristic frequency as the first-harmonic total energy characteristic;

[0013] According to the ratio of the first-harmonic defect energy characteristic to the first-harmonic total energy characteristic, obtain the first-harmonic defect energy factor;

[0014] Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the second set range of frequencies as the second-harmonic defect energy characteristic; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the second-harmonic set range of frequencies corresponding to the theoretical defect characteristic frequency as the second-harmonic total energy characteristic; the minimum frequency value and the maximum frequency value in the second set range of frequencies are respectively twice the minimum frequency value and the maximum frequency value in the first set range of frequencies;

[0015] Obtain the second-harmonic defect energy factor according to the ratio of the second-harmonic defect energy feature to the second-harmonic total energy feature;

[0016] Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the third set range of frequency bands as the third-harmonic defect energy feature; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the third-harmonic set range of frequency bands corresponding to the theoretical defect characteristic frequency as the third-harmonic total energy feature; the minimum frequency value and the maximum frequency value in the third set range of frequency bands are three times the minimum frequency value and the maximum frequency value in the first set range of frequency bands respectively;

[0017] Obtain the third-harmonic defect energy factor according to the ratio of the third-harmonic defect energy feature to the third-harmonic total energy feature;

[0018] Obtain the defect frequency factor of the bearing component according to the superposition result of the first-harmonic, second-harmonic and third-harmonic defect energy factors;

[0019] The first-harmonic set range of frequency bands includes the first set range of frequency bands; the second-harmonic set range of frequency bands includes the second set range of frequency bands; the third-harmonic set range of frequency bands includes the third set range of frequency bands.

[0020] Further, the minimum frequency value in the first set range of frequency bands is obtained by subtracting the set frequency error value from the theoretical defect characteristic frequency, and the maximum frequency value in the first set range of frequency bands is obtained by adding the set frequency error value to the theoretical defect characteristic frequency.

[0021] Further, the minimum frequency value in the first-harmonic set range of frequency bands is obtained by subtracting the set frequency interval value from the theoretical defect characteristic frequency, and the maximum frequency value in the first-harmonic set range of frequency bands is obtained by adding the set frequency interval value to the theoretical defect characteristic frequency;

[0022] The minimum frequency value in the second-harmonic set range of frequency bands is obtained by subtracting the set frequency interval value from twice the theoretical defect characteristic frequency, and the maximum frequency value in the first-harmonic set range of frequency bands is obtained by adding the set frequency interval value to twice the theoretical defect characteristic frequency;

[0023] The minimum frequency value in the third-harmonic set range of frequency bands is obtained by subtracting the set frequency interval value from three times the theoretical defect characteristic frequency, and the maximum frequency value in the third-harmonic set range of frequency bands is obtained by adding the set frequency interval value to three times the theoretical defect characteristic frequency.

[0024] Further, the method for determining whether there is a defect in the bearing component by judging whether the defect frequency factor of the bearing component exceeds the corresponding bearing component failure threshold includes:

[0025] Select the maximum value from the defect frequency factors corresponding to the envelope spectra of the respective IMF components of the bearing component, and determine whether this maximum value exceeds the corresponding bearing component failure threshold; if it exceeds, it is determined that the bearing component has a defect; otherwise, it is determined that the bearing component has no defect.

[0026] Further, the bearing component includes the inner ring, outer ring and rolling elements of the bearing.

[0027] Further, the signal processing module further includes a storage sub-module, and the storage sub-module is used to store the electrical signals obtained by the white light LED receiving module and the analysis results obtained by the analysis sub-module.

[0028] The above technical solution of the present invention provides a brand-new bearing vibration detection system based on white light LEDs, and its beneficial effects include: by converting the bearing vibration information collected by the vibration sensor into a digital signal form convenient for transmission through white light LEDs, and cooperating with the white light LED emission module and the white light LED receiving module for transmission, an electrical signal for extracting the vibration information of the bearing can be finally obtained; since the white light LED signal itself does not affect the operation of the bearing, and under interference conditions such as high temperature, high pressure, and strong electromagnetic interference often encountered by the bearing, the white light LED signal is also basically not restricted, has little influence on the transmitted bearing vibration information and rarely fails to transmit, achieving the effect of strong anti-interference. Description of the Drawings

[0029] Figure 1 is the structural principle block diagram of the bearing vibration detection system based on white light LEDs in the embodiment of the bearing vibration detection system based on white light LEDs of the present invention;

[0030] Figure 2 is the specific working principle example diagram of each module of the bearing vibration detection system based on white light LEDs in the embodiment of the bearing vibration detection system based on white light LEDs of the present invention;

[0031] Figure 3 is the principle flow chart of the analysis module of the bearing vibration detection system based on white light LEDs in the embodiment of the bearing vibration detection system based on white light LEDs of the present invention;

[0032] Figure 4 is the example diagram of the defect frequency factor calculation method of the bearing vibration detection system based on white light LEDs in the embodiment of the bearing vibration detection system based on white light LEDs of the present invention. Detailed Embodiments

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments.

[0034] Embodiment of a Bearing Vibration Detection System Based on White LED

[0035] This embodiment provides a technical solution for a bearing vibration detection system based on white LED. By converting the collected bearing vibration information into a digital signal form convenient for transmission through white LED, and then transmitting the vibration information through the white LED signal, it achieves stronger anti-interference ability, higher efficiency, and easier implementation compared with the existing bearing vibration signal acquisition devices.

[0036] Refer to Figure 1 , the system includes: a vibration sensor for collecting the vibration signals generated by the bearing, a signal conditioning circuit for processing the vibration signals collected by the vibration sensor to obtain the vibration signals in the form of processed digital signals, a white LED emission module for outputting the vibration signals in the form of digital signals obtained by the signal conditioning circuit through the white LED signal, and a white LED receiving module for receiving the white LED signal emitted by the white LED emission module and obtaining the corresponding electrical signal according to the received white LED signal; the electrical signal obtained by the white LED receiving module is used to extract the vibration information of the bearing.

[0037] Thus, the system can convert the bearing vibration information collected by the vibration sensor into a digital signal form convenient for transmission through white LED, and cooperate with the white LED emission module and the white LED receiving module for transmission, and finally obtain the electrical signal used to extract the vibration information of the bearing; since the white LED signal itself does not affect the operation of the bearing, and under the interference conditions such as high temperature, high pressure, and strong electromagnetic interference that the bearing often encounters, the white LED signal is basically not restricted, has little impact on the transmitted bearing vibration information, and rarely fails to transmit, thereby improving the anti-interference ability of vibration signal transmission.

[0038] Moreover, in this embodiment, the adopted vibration sensor collects the vibration signals generated by the bearing by being installed on the bearing housing.

[0039] In addition, as Figure 2 shown, the bearing vibration detection also includes a signal processing module, and the signal processing module includes an analysis sub-module; the analysis sub-module is used to analyze the electrical signal obtained by the white LED receiving module, and the analysis process includes:

[0040] First, convert the electrical signal obtained by the white light LED receiving module into a signal in a frequency band containing the frequency corresponding to the bearing fault to be detected through band-pass filtering. Then, decompose the signal in the frequency band containing the frequency corresponding to the bearing fault to be detected into each IMF component, calculate the envelope spectrum of each IMF component, and then calculate the defect frequency factors corresponding to the envelope spectra of each IMF component of the bearing component to be detected. Determine whether there is a defect in the bearing component by judging whether the above defect frequency factors of the bearing component exceed the corresponding bearing component fault thresholds;

[0041] In this embodiment, the frequency band containing the frequency corresponding to the bearing fault to be detected is 50 Hz - 10 kHz. In other embodiments, the frequency band can also be adjusted according to the frequency corresponding to the bearing fault to be detected.

[0042] In addition, decomposing the signal into each IMF component is implemented through the FMD algorithm. The specific content of this algorithm is prior art and will not be elaborated here.

[0043] The calculation method of the defect frequency factor of the bearing component corresponding to the envelope spectrum of each IMF component includes:

[0044] Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the first set range of frequencies containing the theoretical defect characteristic frequency of the bearing component as the single-frequency defect energy characteristic; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the single-frequency set range of frequencies corresponding to the theoretical defect characteristic frequency as the single-frequency total energy characteristic;

[0045] Obtain the single-frequency defect energy factor according to the ratio of the single-frequency defect energy characteristic to the single-frequency total energy characteristic;

[0046] Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the second set range of frequencies as the double-frequency defect energy characteristic; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the double-frequency set range of frequencies corresponding to the theoretical defect characteristic frequency as the double-frequency total energy characteristic; the minimum frequency value and the maximum frequency value in the second set range of frequencies are respectively twice the minimum frequency value and the maximum frequency value in the first set range of frequencies;

[0047] Obtain the double-frequency defect energy factor according to the ratio of the double-frequency defect energy characteristic to the double-frequency total energy characteristic;

[0048] Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the third set range of frequency bands as the triple-frequency defect energy feature; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the triple-frequency set range of frequencies corresponding to the theoretical defect characteristic frequency as the triple-frequency total energy feature; the minimum frequency value and the maximum frequency value in the third set range of frequency bands are three times the minimum frequency value and the maximum frequency value in the first set range of frequency bands respectively.

[0049] Obtain the triple-frequency defect energy factor according to the ratio of the triple-frequency defect energy feature to the triple-frequency total energy feature.

[0050] Obtain the defect frequency factor of the bearing component according to the superposition result of the defect energy factors of the fundamental frequency, second harmonic frequency and triple frequency.

[0051] The fundamental frequency set range of frequency bands includes the first set range of frequency bands; the second harmonic frequency set range of frequency bands includes the second set range of frequency bands; the triple frequency set range of frequency bands includes the third set range of frequency bands.

[0052] By analyzing the proportion of the energy feature corresponding to the defect frequency in the total energy of the corresponding harmonic region in the cases of the fundamental frequency to the triple frequency respectively, the analysis sub-module obtains the relative energy proportion of the defect frequency under different harmonics. After superimposing the relative energy proportion of the defect frequency under different harmonics, the relative energy proportion of the total defect frequency in the bearing vibration signal can be obtained, from which it can be determined whether there are large defect frequency components in the bearing vibration signal, and thus whether there are corresponding defects in the bearing.

[0053] In this embodiment, the method for obtaining the fundamental frequency defect energy factor according to the ratio of the fundamental frequency defect energy feature to the fundamental frequency total energy feature is specifically as follows: exponentiate the ratio of the fundamental frequency defect energy feature to the fundamental frequency total energy feature to enhance the sensitivity of the frequency defect energy factor; use the exponentiated ratio as the fundamental frequency defect energy factor.

[0054] Similarly, the method for obtaining the second harmonic frequency defect energy factor according to the ratio of the second harmonic frequency defect energy feature to the second harmonic frequency total energy feature is specifically as follows: exponentiate the ratio of the second harmonic frequency defect energy feature to the second harmonic frequency total energy feature to enhance the sensitivity of the frequency defect energy factor; use the exponentiated ratio as the second harmonic frequency defect energy factor.

[0055] The method for obtaining the triple frequency defect energy factor according to the ratio of the triple frequency defect energy feature to the triple frequency total energy feature is specifically as follows: exponentiate the ratio of the triple frequency defect energy feature to the triple frequency total energy feature to enhance the sensitivity of the frequency defect energy factor; use the exponentiated ratio as the triple frequency defect energy factor.

[0056] Refer toFigure 3 , the method of determining whether there is a defect in the bearing component by judging whether the defect frequency factor of the bearing component exceeds the corresponding bearing component failure threshold specifically includes:

[0057] Select the maximum value from the defect frequency factors corresponding to the envelope spectra of the respective IMF components of the bearing component, and judge whether the maximum value exceeds the corresponding bearing component failure threshold; if it exceeds, it is determined that the bearing component has a defect; otherwise, it is determined that the bearing component has no defect.

[0058] Specifically, the minimum frequency value in the first set range frequency band is obtained by subtracting the set frequency error value from the theoretical defect characteristic frequency, and the maximum frequency value in the first set range frequency band is obtained by adding the set frequency error value to the theoretical defect characteristic frequency. That is, considering that only the energy value at the frequency point of the theoretical defect characteristic frequency may be affected by the slight difference between the actual defect characteristic frequency value and the theoretical value, therefore, a narrow band interval (set frequency error value) of the same size is taken on both sides of the theoretical defect characteristic frequency, and the energy value in the region composed of the theoretical defect characteristic frequency and these two narrow band intervals is taken as the energy value corresponding to the theoretical defect characteristic frequency; it is equivalent to correcting the theoretical defect characteristic frequency f n to a narrow band frequency band [f n -Δf n , f n +Δf n , where Δf n is the set frequency error value. Because the actual defect characteristic frequency value may have a slight difference from the theoretical value due to the combined influence of factors such as the dimensional deviation of the bearing element, the change of the bearing rotation speed, and the change of the load, in this embodiment, Δf n =7Hz. Considering the allowable value of the change of the main shaft rotation speed of the vibration measuring instrument, the value range of Δf n is 3Hz - 10Hz. In other embodiments, the size of Δf n can be adjusted adaptively. In addition, considering that the deviation between the theoretical defect characteristic frequency and the actual frequency will further increase when calculating the second harmonic frequency, the minimum frequency value and the maximum frequency value in the second set range frequency band are respectively twice the minimum frequency value and the maximum frequency value in the first set range frequency band; similarly, the minimum frequency value and the maximum frequency value in the third set range frequency band are respectively three times the minimum frequency value and the maximum frequency value in the first set range frequency band.

[0059] On this basis, the minimum frequency value in the fundamental frequency set range frequency band is obtained by subtracting the set frequency interval value from the theoretical defect characteristic frequency, and the maximum frequency value in the fundamental frequency set range frequency band is obtained by adding the set frequency interval value to the theoretical defect characteristic frequency;

[0060] The minimum frequency value in the frequency range of the double frequency setting range is obtained by subtracting the set frequency interval value from twice the theoretical defect characteristic frequency, and the maximum frequency value in the frequency range of the single frequency setting range is obtained by adding twice the theoretical defect characteristic frequency to the set frequency interval value.

[0061] The minimum frequency value in the frequency segment of the triple frequency setting range is obtained by subtracting the set frequency interval value from three times the theoretical defect characteristic frequency, and the maximum frequency value in the frequency segment of the triple frequency setting range is obtained by adding three times the theoretical defect characteristic frequency to the set frequency interval value.

[0062] In this embodiment, the frequency interval value is set to 0.3 times the theoretical defect characteristic frequency f n , that is, the frequency range of the one-time frequency setting range is [0.7f n ,1.3f n ], the double frequency setting range frequency range is [1.7f n ,2.3f n ]; The frequency range of the triple frequency setting range is [2.7f n ,3.3f n ].

[0063] Considering that the deviation between the theoretical defect characteristic frequency and the actual defect characteristic frequency will continue to increase when calculating the fourth harmonic, which will bring about a large error, the parameters required for the defect frequency factor of the bearing component of this embodiment include defect energy factors of one to three times the frequency, and do not include defect energy factors of higher harmonics.

[0064] In this embodiment, considering the need for bearing defect detection, the above-mentioned bearing components include the inner ring, outer ring and rolling elements of the bearing. In other embodiments, other bearing components can also be used as the bearing components to be detected.

[0065] Reference Figure 3 , taking a specific processing flow of the analysis submodule as an example, the work content of the above analysis submodule is explained:

[0066] The analysis submodule first converts the original signal (the electrical signal obtained by the white light LED receiving module, that is, the bearing vibration signal) into a 50Hz-10kHz signal through bandpass filtering, and then decomposes the original signal into IMF components through the FMD algorithm. By calculating the envelope spectrum of each IMF component, and then calculating the inner ring, outer ring and rolling element defect frequency factors of each envelope spectrum one by one, it is finally determined whether the defect frequency factor exceeds the set threshold to determine whether the bearing has defect characteristics. Based on the electrical signal obtained by the white light LED receiving module, the bearing status information is evaluated.

[0067] like Figure 4 As shown, f nFor the calculated theoretical defect characteristic frequency, when calculating the defect frequency factor, f n is corrected to a narrow-band frequency range [f n -Δf n , f n +Δf n . Take Δf n = 7 Hz. Then calculate the first-harmonic defect energy factor E 1n according to the following formula. At the same time, to enhance the sensitivity of the defect frequency factor, it is exponentiated:

[0068]

[0069] In the formula, E 1a is the sum of the amplitudes of the discrete frequencies within the first-harmonic defect characteristic frequency range (the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the first-set range frequency band), and E 1b is the sum of the amplitudes of all frequencies within the first-harmonic defect characteristic frequency (the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the first-harmonic set range frequency band corresponding to the theoretical defect characteristic frequency).

[0070]

[0071] In the formula, W j is the amplitude of each discrete frequency calculated within the range of [f n -7, f n +7].

[0072] To avoid the influence of signal energy in other frequency bands on the calculation result, calculate the total energy E 1b of the frequency-domain signal within the first-harmonic range. Here, the first-harmonic range is taken as [0.7f n , 1.3f n .

[0073]

[0074] Similarly, calculate the defect frequency E n of the defect characteristic frequency 2f 2a (the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the second-set range frequency band) and the total frequency E 2b (the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the second-harmonic set range frequency band corresponding to the theoretical defect characteristic frequency), and the second-harmonic defect energy factor E 2n . Take the range of 2f n as [2f n -2Δf n , 2f n +2Δf n . Also take Δf n= 7Hz, the second harmonic frequency range is taken as [1.7f n , 2.3f n . Similarly, the calculation method of the third harmonic defect energy factor E 3n is the same as that of the second harmonic defect energy factor. By superimposing the obtained defect frequency factors, the defect frequency factor E1 of the bearing component can be obtained.

[0075] E1 = E 1n + E 2n + E 3n

[0076] Considering that the deviation between the theoretical defect characteristic frequency and the actual defect characteristic frequency will continue to increase when calculating the fourth harmonic, which will bring a large error, the calculation is not carried out here. Through the above calculation method of the defect frequency factor of the bearing component, the defect frequency factors E o 、E i and E w of the inner ring, outer ring and rolling elements in the envelope spectrum of each IMF component can be calculated. By comparison, the maximum defect frequency factors E omax 、E imax and E wmax of the inner ring, outer ring and rolling elements are obtained. Then, E omax 、E imax and E wmax are respectively compared with the corresponding thresholds to judge the bearing state.

[0077] In addition, in this embodiment, the signal processing module further includes a storage sub-module, which is used to store the electrical signals obtained by the white light LED receiving module and the bearing state information obtained by the analysis sub-module. This facilitates the analysis sub-module to call the electrical signals obtained by the white light LED receiving module, and also facilitates the call of the analysis results (including the judgment results on whether there are defects in the bearing components) obtained by the analysis sub-module. In this embodiment, the signal conditioning circuit includes a filter circuit (i.e., the filter circuit in Figure 2 ), a first amplifier circuit (i.e., the amplifier circuit connected to the output of the filter circuit in Figure 2 ) and an analog-to-digital conversion sub-module (i.e., the analog-to-digital conversion circuit in Figure 2 ). The filter circuit is used to retain the signals in the frequency band corresponding to the vibration signals generated by the bearing through filtering, while filtering out the signals in other frequency bands, and retaining the signals of 50Hz - 10kHz. Therefore, it can effectively filter out the high-frequency noise from the environment and other interference signals, and retain the effective frequency band of the bearing vibration signals; the first amplifier circuit is used to amplify the vibration signals filtered by the filter circuit to within a set amplitude range, so as to amplify the weak vibration signals after filtering to an amplitude suitable for subsequent processing; the analog-to-digital conversion sub-module is used to convert the vibration signals amplified by the first amplifier circuit into digital signal form.

[0078] The white light LED emission module includes a white light LED and a driving circuit (i.e., the white light LED and the driving circuit in Figure 2 ); the driving circuit is used to provide current drive for the white light LED, so as to output the vibration signal in the form of a digital signal obtained by the signal conditioning circuit as a white light LED signal through the white light LED. The white light LED is selected with a high-brightness and high-light-efficiency model to ensure that the emitted white light LED signal has sufficient intensity and stability; the circuit principle of the driving circuit is as shown in Figure 3 . Based on the constant current drive technology, it can provide stable current drive for the white light LED, so that it emits white light LED signals according to a predetermined frequency and coding method. In other embodiments, other devices or functional modules capable of realizing white light LED emission can also be used.

[0079] The white light LED receiving module includes a photoelectric conversion device (i.e., the photoelectric conversion part in Figure 2 ) and a second amplifier circuit (i.e., the amplifier circuit connected to the output of the photoelectric conversion part in Figure 2 ); the photoelectric conversion device is used to receive the white light LED signal emitted by the white light LED emission module and convert the received white light LED signal into an electrical signal; the second amplifier circuit is used to amplify the electrical signal converted by the photoelectric conversion device.

[0080] In an actual application scenario, the bearing vibration detection system of this embodiment is installed at a suitable position near the bearing to be monitored, and it is ensured through debugging that the vibration sensor is in good contact with the bearing. During the operation of the equipment, the vibration sensor continuously detects the vibration signal of the bearing, and these signals are immediately transmitted to the signal conditioning circuit. After removing noise interference through the filter circuit, increasing the signal amplitude through the first amplifier circuit, and digital processing by the analog-to-digital conversion sub-module, they are transmitted to the white light LED emission module. The driving circuit in the white light LED emission module drives the white light LED to quickly emit white light LED signals according to a specific coding method.

[0081] At the receiving end, the photoelectric conversion device in the white light LED receiving module captures these white light LED signals and converts them into current signals. Subsequently, the second amplifier circuit amplifies and processes the noise of the current signal to make it a good-quality electrical signal. This electrical signal is transmitted to the signal processing module, and the analysis sub-module in the signal processing module uses the FMD decomposition algorithm for decomposition processing, takes the envelope spectrum of the decomposed IMF components, calculates the defect frequency factors in each envelope spectrum, compares the obtained maximum defect frequency factor with the set threshold, and finally accurately obtains the defect information of the bearing. At the same time, the storage sub-module records the vibration signal and the bearing status information. Through such a continuous working process, the real-time and accurate monitoring of the bearing operation status is realized, providing a strong guarantee for the normal operation and maintenance of the equipment.

[0082] It should be understood that the above specific embodiments of the present invention are only used for exemplary illustration or explanation of the principles of the present invention, and do not constitute a limitation to the present invention.

Claims

1. A bearing vibration detection system based on white light LEDs, characterized in that Including: A vibration sensor for collecting vibration signals generated by a bearing, a signal conditioning circuit for processing the vibration signals collected by the vibration sensor into digital signal form, and a white LED emission module for outputting the vibration signals in digital signal form obtained by the signal conditioning circuit through white LED signals; and a white LED receiving module for receiving the white LED signals emitted by the white LED emission module; the electrical signals obtained by the white LED receiving module are used to extract the vibration information of the bearing.

2. The bearing vibration detection system based on white light LEDs according to claim 1, wherein The white LED emission module includes a white LED and a driving circuit; the driving circuit is used to provide current drive for the white LED to output the vibration signals in digital signal form obtained by the signal conditioning circuit as white LED signals through the white LED.

3. The bearing vibration detection system based on white light LEDs according to claim 1 or 2, characterized in that, The white LED receiving module includes a photoelectric conversion device and a second amplifier circuit; The photoelectric conversion device is used to receive the white LED signals emitted by the white LED emission module and convert the received white LED signals into electrical signals; the second amplifier circuit is used to amplify the electrical signals converted by the photoelectric conversion device.

4. The bearing vibration detection system based on white light LED according to claim 1 or 2, characterized in that It further includes a signal processing module; The signal processing module includes an analysis sub-module; the analysis sub-module is used to analyze the electrical signals obtained by the white LED receiving module, and the analysis process includes: First, convert the electrical signals obtained by the white LED receiving module into signals in a frequency band containing the frequencies corresponding to the faults of the bearing to be detected through band-pass filtering, then decompose the signals in the frequency band into each IMF component, calculate the envelope spectrum of each IMF component, and then calculate the defect frequency factors corresponding to the envelope spectra of each IMF component of the bearing components to be detected. Determine whether there are defects in the bearing components by judging whether the defect frequency factors of the bearing components exceed the corresponding bearing component fault thresholds; The calculation method of the defect frequency factor of the bearing component corresponding to the envelope spectrum of each IMF component includes: Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within a first set range of frequencies including the theoretical defect characteristic frequency of the bearing component as the single-frequency defect energy characteristic; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within a single-frequency set range of frequencies corresponding to the theoretical defect characteristic frequency as the single-frequency total energy characteristic; Obtain the single-frequency defect energy factor according to the ratio of the single-frequency defect energy characteristic to the single-frequency total energy characteristic; Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within a second set range of frequencies as the double-frequency defect energy characteristic; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within a double-frequency set range of frequencies corresponding to the theoretical defect characteristic frequency as the double-frequency total energy characteristic; the minimum frequency value and the maximum frequency value in the second set range of frequencies are respectively twice the minimum frequency value and the maximum frequency value in the first set range of frequencies; Obtain the double-frequency defect energy factor according to the ratio of the double-frequency defect energy characteristic to the double-frequency total energy characteristic; Calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the third set range of frequency bands as the triple-frequency defect energy feature; and calculate the sum of the amplitudes of the discrete frequencies of the envelope spectrum of the current IMF component within the triple-frequency set range of frequency bands corresponding to the theoretical defect characteristic frequency as the triple-frequency total energy feature; the minimum frequency value and the maximum frequency value in the third set range of frequency bands are three times the minimum frequency value and the maximum frequency value in the first set range of frequency bands, respectively. Obtain the triple-frequency defect energy factor according to the ratio of the triple-frequency defect energy feature to the triple-frequency total energy feature. Obtain the defect frequency factor of the bearing component according to the superposition result of the single-frequency, double-frequency, and triple-frequency defect energy factors. The single-frequency set range of frequency bands includes the first set range of frequency bands; the double-frequency set range of frequency bands includes the second set range of frequency bands; the triple-frequency set range of frequency bands includes the third set range of frequency bands.

5. The bearing vibration detection system based on white light LED according to claim 4, characterized in that, The minimum frequency value in the first set range of frequency bands is obtained by subtracting the set frequency error value from the theoretical defect characteristic frequency, and the maximum frequency value in the first set range of frequency bands is obtained by adding the set frequency error value to the theoretical defect characteristic frequency.

6. The bearing vibration detection system based on white light LEDs according to claim 5, wherein, The minimum frequency value in the single-frequency set range of frequency bands is obtained by subtracting the set frequency interval value from the theoretical defect characteristic frequency, and the maximum frequency value in the single-frequency set range of frequency bands is obtained by adding the set frequency interval value to the theoretical defect characteristic frequency. The minimum frequency value in the double-frequency set range of frequency bands is obtained by subtracting the set frequency interval value from twice the theoretical defect characteristic frequency, and the maximum frequency value in the single-frequency set range of frequency bands is obtained by adding the set frequency interval value to twice the theoretical defect characteristic frequency. The minimum frequency value in the triple-frequency set range of frequency bands is obtained by subtracting the set frequency interval value from three times the theoretical defect characteristic frequency, and the maximum frequency value in the triple-frequency set range of frequency bands is obtained by adding the set frequency interval value to three times the theoretical defect characteristic frequency.

7. The bearing vibration detection system based on white light LEDs according to claim 4, wherein The method for determining whether there is a defect in the bearing component by determining whether the defect frequency factor of the bearing component exceeds the corresponding bearing component failure threshold includes: Select the maximum value from the defect frequency factors corresponding to the envelope spectra of the respective IMF components of the bearing component, and determine whether the maximum value exceeds the corresponding bearing component failure threshold; if it exceeds, it is determined that the bearing component has a defect; otherwise, it is determined that the bearing component has no defect.

8. The bearing vibration detection system based on white light LEDs according to claim 4, wherein The bearing component includes the inner ring, outer ring, and rolling elements of the bearing.

9. The bearing vibration detection system based on white light LEDs according to claim 4, wherein, The signal processing module further includes a storage sub-module, and the storage sub-module is used to store the electrical signals obtained by the white light LED receiving module and the analysis results obtained by the analysis sub-module.

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