Rotary machinery vibration signal angular domain sampling method

Abstract

The invention provides a rotary machine vibration signal angular domain sampling method, and relates to the technical field of rotary machine state monitoring and fault diagnosis. The method comprises the following steps: establishing a synchronous data acquisition channel of a rotary encoder and a vibration sensor through a common clock source; establishing a vibration sensor data first-in first-out cache aligned with an encoder channel timestamp on the basis of the synchronous data acquisition channel; angular domain sampling data screening triggered by the edge of the rotary encoder is realized on the basis of vibration sensor data oversampling; and finally, sorting the screened vibration sensor data according to instantaneous angle values to form angular domain sampling vibration signals. According to the method, angular domain equal-angle interval sampling is realized from a data acquisition source, instantaneous rotating speed calculation and time domain signal interpolation are not needed, the problem of signal distortion caused by an interpolation algorithm in a traditional order tracking technology is effectively avoided, the fidelity and analysis efficiency of angular domain vibration signals are remarkably improved, and the method is suitable for large-scale popularization and application. And a reliable data basis is provided for accurate fault diagnosis of the rotating machinery.

Description

Technical Field

[0001] This invention relates to the field of rotating machinery condition monitoring and fault diagnosis technology, and in particular to a method for angular domain sampling of vibration signals of rotating machinery. Background Technology

[0002] Rotating machinery, such as engines, gearboxes, and compressors, is core equipment in industrial production and energy sectors, and its operating status directly affects the safety and reliability of the entire system. Vibration signal analysis, as one of the most important technical means for fault diagnosis and predictive maintenance of rotating machinery, is crucial for the accuracy of its analysis results. In actual operating conditions, rotating machinery often operates during transient processes such as start-up, shutdown, or load changes, exhibiting significant non-stationary characteristics in its rotational speed. However, limited by the basic principles of data acquisition systems, currently widely used vibration signal acquisition methods all employ equal-interval sampling based on a fixed-frequency clock source. This sampling method is applicable when the rotational speed is constant or changes minimally, but when the rotational speed fluctuates, the acquired time-domain vibration signals are actually not equally spaced in the angular domain. This makes it impossible to directly and clearly extract the fault characteristic frequencies related to rotational speed harmonics, i.e., the "order" components, thus greatly affecting the accuracy of fault identification.

[0003] To obtain equally spaced angular signals from vibration signals sampled at equal time intervals, the industry currently relies heavily on "order tracking" technology. This type of technology is a post-processing algorithm. Its core idea is to first estimate the instantaneous rotational speed of the rotating machinery using an additional speed measurement device (such as an encoder), and then resample or interpolate the equally spaced vibration signals based on this instantaneous rotational speed to finally reconstruct the equally spaced angular vibration signals. Although this method is relatively mature, it has two inherent and difficult-to-overcome drawbacks. First, the introduction of interpolation algorithms inevitably leads to signal distortion. Whether it is linear interpolation or high-order spline interpolation, it is a prediction and fitting of the original signal, which cannot completely restore the true vibration state. Especially for high-frequency components and impact fault characteristics, the smoothing effect will cause amplitude attenuation and phase distortion, resulting in the loss of diagnostic information. Second, the computational complexity of the entire order tracking process is very high. The precise calculation of instantaneous rotational speed requires processing encoder pulse signals, and the subsequent interpolation calculations are computationally intensive tasks. This not only places high demands on processor performance, increasing system costs, but also makes the entire analysis process time-consuming, making it difficult to meet the needs of online monitoring and real-time diagnosis of equipment. Furthermore, the selection of different interpolation algorithms and their parameter settings have a significant impact on the final results, making it difficult to guarantee the stability and consistency of the analysis results.

[0004] Therefore, in the field of rotating machinery condition monitoring and fault diagnosis, there has long been an urgent need: whether it is possible to directly obtain vibration signals at angular intervals in the angular domain from the source of data acquisition, thereby completely avoiding the dependence on interpolation algorithms, improving signal fidelity, simplifying data processing procedures, and improving analysis efficiency. Summary of the Invention

[0005] To address the technical problems of signal distortion, computational complexity, and poor real-time performance in rotating machinery vibration signal analysis caused by reliance on post-processing interpolation algorithms in existing technologies, this invention provides a rotating machinery vibration signal angular domain sampling method.

[0006] The technical solution provided by this invention is as follows: This invention provides a method for angular domain sampling of vibration signals from rotating machinery, comprising: A synchronous data acquisition channel for the rotary encoder and vibration sensor is established by sharing a clock source; Based on the synchronous data acquisition channel, a first-in-first-out (FIFO) buffer for vibration sensor data is established, aligned with the encoder channel timestamp. Based on the oversampling of vibration sensor data, the angular domain sampling data is filtered by the edge of the rotary encoder. The filtered vibration sensor data are sorted by instantaneous angle values ​​to form angular domain sampling vibration signals.

[0007] Furthermore, the rotary encoder and the vibration sensor data acquisition channel share the same clock source.

[0008] Furthermore, the rotary encoder data acquisition channel includes an encoder, a first-order RC filter, an optocoupler isolation unit, and a microcontroller unit (MCU). The MCU is configured to directly generate valid data timestamps using edge triggering of the rotary encoder.

[0009] Furthermore, the vibration sensor data acquisition channel consists of an analog-to-digital converter (AD), a first-in-first-out (FIFO) buffer, and an MCU, with a minimum sampling frequency of [missing value]. Calculated using the following formula: In the formula For encoder lines, The number of revolutions per minute of the rotating machinery being tested.

[0010] Furthermore, the vibration sensor data FIFO and the rotary encoder trigger edge signal have synchronized timestamps; Let the time of the nth trigger edge signal of the rotary encoder be... This moment corresponds to the instantaneous phase of the rotating machinery being measured. ; When a trigger edge signal is generated, the sample with the closest sampling timestamp is selected from the FIFO. Vibration sensor data, as instantaneous phase The corresponding vibration signal data.

[0011] Furthermore, the data segments stored in the vibration sensor data FIFO in chronological order have the following first register timestamp sequence: ; For encoder trigger time Seeking satisfaction The interval is defined, and from the FIFO data corresponding to that interval, the sample time stamp closest to the defined interval is selected. Vibration data Forming corner domain sampling data pairs .

[0012] Furthermore, the shared clock source includes a first crystal oscillator and a second crystal oscillator; The first crystal oscillator is used to provide the core operating clock for the MCU, and the second crystal oscillator is specifically used to generate the synchronization timestamp.

[0013] Furthermore, the MCU's timer enables encoder mode, counts the encoder pulse edges, and captures the rising edge of the encoder signal in real time through the input capture function to record the trigger time.

[0014] Furthermore, the MCU adds a fixed-interval acquisition timestamp to each AD conversion value, forming timestamped data, which is then stored sequentially in the FIFO.

[0015] Furthermore, all the selected vibration sensor data are analyzed according to their corresponding instantaneous phase. The signals are sorted to obtain a vibration signal sequence with equal angular intervals in the angular domain.

[0016] The beneficial effects of the technical solution provided by this invention include at least the following: (1) In this invention, by constructing a data acquisition channel that shares a synchronous clock source with the rotary encoder and vibration sensor, and by directly filtering the oversampled vibration data based on encoder edge triggering, angular domain sampling from the source is achieved. This fundamental change eliminates the need for any form of interpolation calculation in the angular domain sampling process of the vibration signal. It directly avoids the signal amplitude attenuation and phase distortion introduced by the inherent prediction and fitting characteristics of interpolation algorithms, and can completely preserve the high-frequency components and instantaneous impact characteristics in the original vibration signal, significantly improving the fidelity of the angular domain vibration signal, and providing a more realistic and reliable data foundation for subsequent accurate fault diagnosis.

[0017] (2) In this invention, the method utilizes a hardware synchronization and triggering mechanism to replace the complex software algorithm in traditional order tracking technology. The system does not need to perform tedious instantaneous rotational speed calculations, nor does it need to perform computationally intensive interpolation and resampling operations. This greatly simplifies the overall process from data acquisition to angular domain signal generation and reduces the dependence on microprocessor computing performance. The direct result is a significant improvement in data processing efficiency, enabling faster completion of vibration state analysis of rotating machinery, effectively supporting online real-time monitoring of equipment and rapid early warning of faults, and improving the response speed and practicality of the entire monitoring system.

[0018] (3) In this invention, by precisely synchronizing the clock and aligning the timestamps, and by combining the minimum oversampling rate set for vibration data acquisition according to a specific formula, it is ensured that at the encoder triggering time of each characterizing angle, the closest real vibration data point in time can always be found from the cache. This "hardware synchronization screening" mechanism not only ensures the equiangular interval characteristics of the angular domain sampling points, but also ensures that each data point originates from an actual physical sampling, rather than mathematical derivation. This method fundamentally eliminates the influence of algorithm selection and parameter settings on the analysis results, ensuring the consistency and repeatability of analysis results between different measurements and different devices, while taking into account both signal accuracy and system processing efficiency, providing a new technical path for achieving highly reliable and efficient intelligent diagnosis of rotating machinery. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic flowchart of a method for sampling angular domain vibration signals of rotating machinery provided in an embodiment of the present invention; Figure 2 A software flowchart illustrating a method for sampling vibration signals in the angular domain of rotating machinery, provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the hardware system architecture for a method for sampling angular domain vibration signals of rotating machinery, provided in an embodiment of the present invention. Figure 4 This is a schematic diagram of encoder-triggered FIFO data in a rotating machinery vibration signal angular domain sampling method provided in an embodiment of the present invention. Detailed Implementation

[0021] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0022] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0023] In embodiments of the present invention, sometimes the subscript is as follows: It may be mistakenly written as a non-subscript form such as W1. When the distinction is not emphasized, the meaning they express is the same.

[0024] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0025] Reference manual attached Figure 1-2 The diagram shows a flowchart and a software flowchart of a method for sampling angular domain vibration signals of rotating machinery provided by an embodiment of the present invention.

[0026] This invention provides a method for angular domain sampling of vibration signals from rotating machinery, the processing flow of which may include the following steps: A synchronous data acquisition channel for the rotary encoder and vibration sensor is established by sharing a clock source.

[0027] In practical implementation, the first step is to construct a unified synchronous clock system to ensure the coordinated acquisition of two key data types: rotary encoder and vibration sensor. This method employs a shared clock source to achieve synchronization in the time dimension, specifically through a dual-crystal oscillator collaborative scheme: one crystal oscillator serves as the core operating clock, directly providing timing support to the microcontroller unit (MCU), ensuring strict timing synchronization when controlling the rotary encoder edge trigger detection and the analog-to-digital converter (ADC) chip data acquisition; the other crystal oscillator is dedicated to timestamp recording, accurately recording the specific moment of each encoder edge trigger and the timestamp information for fixed-interval acquisition of vibration sensor data. This design avoids acquisition phase differences caused by clock deviations, establishing a time reference for subsequent data matching.

[0028] Based on the synchronous data acquisition channel, a first-in-first-out (FIFO) buffer for vibration sensor data is established, which is aligned with the encoder channel timestamp.

[0029] After the synchronous data acquisition channel is established, the vibration sensor data acquisition channel performs high-precision and high-speed acquisition and stores the data in a first-in-first-out (FIFO) buffer. Specifically, the microcontroller unit adds a corresponding fixed-interval acquisition timestamp to each analog-to-digital conversion value. This timestamp and the timestamp of the encoder data acquisition channel originate from the same clock source, ensuring that the time bases of the two types of data are consistent. The timestamped analog-to-digital conversion data are stored in the FIFO buffer sequentially according to the acquisition order, forming structured data of "value plus timestamp". This storage method not only avoids data loss but also allows for quick indexing of the acquisition time corresponding to each vibration data point, facilitating subsequent time matching with the encoder trigger time data table.

[0030] Based on the oversampling of vibration sensor data, the angular domain sampling data is filtered by the edge of the rotary encoder.

[0031] Based on the oversampling of vibration sensor data, when the rotary encoder generates an edge trigger signal due to mechanical rotation, the microcontroller records the trigger moment and its corresponding instantaneous phase of the measured machine. At this time, multiple sets of structured data with timestamps are already cached in the vibration sensor data first-in-first-out buffer. Through time axis comparison, when the encoder trigger moment falls between two consecutive timestamps in the buffer, the vibration data with the sampling time closest to the encoder trigger moment is selected from the cached data in that interval and adopted as the vibration signal data corresponding to that instantaneous phase. This selection process is based on a strict time synchronization benchmark and does not require instantaneous speed calculation or interpolation; data selection is directly achieved through hardware triggering.

[0032] The filtered vibration sensor data are sorted by instantaneous angle values ​​to form angular domain sampling vibration signals.

[0033] After data screening, all adopted vibration sensor data are sorted according to their corresponding instantaneous phase values. Specifically, each adopted vibration data uniquely corresponds to the mechanical instantaneous phase represented by the trigger edge of a rotary encoder. Arranging these data in order of instantaneous phase forms a complete angular domain sampled vibration signal. This signal directly reflects the vibration characteristics of rotating machinery at different angular positions, providing an accurate data foundation for subsequent angular domain analysis. The entire process does not require interpolation algorithms to convert the time-domain signal into an angular-domain signal.

[0034] In one possible implementation, the rotary encoder and the vibration sensor data acquisition channel share the same clock source.

[0035] When constructing the synchronous data acquisition channel, the rotary encoder and vibration sensor data acquisition channels share the same clock source system. This clock source system adopts a dual-crystal collaborative scheme, where an 8MHz crystal oscillator serves as the core operating clock, directly providing timing support for the MCU, while a 32.768KHz crystal oscillator is dedicated to timestamp recording. Through this design, the moment of the encoder trigger edge always corresponds to a set of vibration sensor data, ensuring the time synchronization of the two types of data at the acquisition source.

[0036] In one possible implementation, the rotary encoder data acquisition channel includes an encoder, a first-order RC filter, an optocoupler, and a microcontroller unit (MCU). The MCU is configured to directly generate valid data timestamps using edge triggering of the rotary encoder.

[0037] like Figure 3 As shown, the specific hardware implementation of the rotary encoder data acquisition channel includes a 1000-line rotary encoder, a first-order RC filter, an optocoupler isolation circuit, and an STM32 series MCU. The A-phase or B-phase signal output from the encoder first passes through a first-order RC filter to remove high-frequency noise, then undergoes electrical isolation through the optocoupler isolation circuit, and finally connects to the MCU's timer channel pin. The MCU timer enables encoder mode, counting pulse edges through a dedicated register, with both the rising and falling edges of each phase signal triggering the count to improve the resolution of angular displacement detection.

[0038] The encoder selected for this channel has two-phase quadrature output signals, A and B, which can adapt to the motor's maximum speed requirement of 600 rpm (600 revolutions per minute) and accurately reflect the angular displacement changes of rotating machinery.

[0039] In one possible implementation, the vibration sensor data acquisition channel consists of an analog-to-digital converter (AD), a first-in-first-out (FIFO) buffer, and an MCU, with a minimum sampling frequency. Calculated using the following formula: In the formula Encoder line count, The number of revolutions per minute of the rotating machinery being tested.

[0040] The vibration sensor data acquisition channel consists of a 24-bit resolution AD chip, a first-in-first-out (FIFO) buffer, and an MCU. To meet sampling requirements, the minimum sampling frequency is determined using the above formula. In practical implementation, for a 1000-line encoder and a maximum speed of 600 rpm, the calculated... The selected AD chip has a sampling rate of up to 2MSPS, which is much higher than the minimum value, ensuring that there is vibration sensor data before and after each encoder trigger edge.

[0041] To meet this requirement and reserve a certain amount of redundancy, a 24-bit resolution AD chip was selected, with a sampling rate of up to 2MSPS (megasamples per second). The high resolution of 24 bits can accurately quantize the weak signal output by the vibration sensor, reducing signal quantization error, while the sampling rate of 2MSPS is much higher than... This ensures that signal characteristics can still be completely acquired even when the vibration signal frequency is high, avoiding signal aliasing.

[0042] In one possible implementation, the vibration sensor data FIFO has a synchronized timestamp with the rotary encoder trigger edge signal; Let the time of the nth trigger edge signal of the rotary encoder be... This moment corresponds to the instantaneous phase of the rotating machinery being measured. ; When a trigger edge signal is generated, the sample with the closest sampling timestamp is selected from the FIFO. Vibration sensor data, as instantaneous phase The corresponding vibration signal data.

[0043] like Figure 4 As shown, the vibration sensor data FIFO and the encoder trigger edge signal share the same time base. The time when the encoder generates the trigger edge signal... At that time, the corresponding instantaneous phase of the measured machine At this point, the vibration FIFO has cached multiple sets of structured data consisting of "ADC values ​​+ timestamps". By comparing the timelines, the data with the closest sampling timestamps is selected. Vibration data as phase The corresponding vibration signal data.

[0044] In one possible implementation, the data segments stored in the vibration sensor data FIFO in chronological order have a first register timestamp sequence of... ; For encoder trigger time Seeking satisfaction The interval is defined, and from the FIFO data corresponding to that interval, the sample time stamp closest to the defined interval is selected. Vibration data Forming corner domain sampling data pairs .

[0045] The specific execution process of data filtering is as follows: The data segments stored in the vibration sensor data FIFO in chronological order have the following timestamp sequence in their first register: For each encoder trigger time Seeking satisfaction Within a given interval, select the data from the FIFO data corresponding to that interval whose sampling timestamp is closest. Vibration data Forming corner domain sampling data pairs This process iterates through all encoder trigger edge moments to ensure that each phase point has corresponding vibration data.

[0046] For example, such as Figure 4 As shown, when the encoder generates the next trigger edge (corresponding to the instantaneous phase) ), record time :like Still in and within the time interval Then continue to select from the FIFO data in that interval. Closest ADC value ,form ;like Exceeding the current range Then it will automatically match the subsequent FIFO interval. until satisfaction is found The range, then filter the corresponding And so on, iterating through all the trigger edges of the encoder. This allows us to obtain the phase at each instant. One-to-one vibration data .

[0047] In one possible implementation, the shared clock source includes a first crystal oscillator and a second crystal oscillator; The first crystal oscillator is used to provide the core operating clock for the MCU, and the second crystal oscillator is specifically used to generate the synchronization timestamp.

[0048] The specific configuration of the shared clock source using the dual crystal oscillator collaborative scheme is as follows: an 8MHz crystal oscillator serves as the core working clock, providing timing support for the MCU and ensuring strict synchronization between the rotary encoder edge trigger detection and the AD chip data acquisition; a 32.768KHz crystal oscillator is specifically used for timestamp recording, and its low power consumption and high stability characteristics can accurately record the encoder edge trigger time and the vibration sensor data acquisition timestamp.

[0049] In one possible implementation, the MCU's timer enables encoder mode, counts encoder pulse edges, and captures the rising edge of the encoder signal in real time through the input capture function to record the trigger time.

[0050] The specific implementation of enabling encoder mode using the MCU timer includes: counting encoder pulse edges through a dedicated register, with both rising and falling edges of each phase signal triggering the count; simultaneously, capturing the rising edge of encoder phase A or phase B signal in real time through the timer's input capture function, and immediately recording the current trigger time once a rising edge is detected, generating a complete pulse trigger time data table.

[0051] In one possible implementation, the MCU adds a fixed-interval acquisition timestamp to each AD conversion value, forming timestamped data, which is then stored sequentially in the FIFO.

[0052] The MCU adds a fixed-interval acquisition timestamp to each ADC conversion value. This timestamp originates from the same 32.768kHz crystal oscillator as the encoder data acquisition channel timestamp. The timestamped ADC data is transmitted to the MCU via the SPI bus and stored sequentially in a FIFO according to the acquisition order, forming structured buffer data of "ADC value + timestamp", providing a complete data foundation for subsequent time matching.

[0053] The AD chip establishes a communication connection with the MCU through the SPI bus. The high-speed transmission characteristics of the SPI bus can ensure that the digital signal after AD conversion is quickly transmitted to the MCU.

[0054] In one possible implementation, all the selected vibration sensor data are processed according to their corresponding instantaneous phase. The signals are sorted to obtain a vibration signal sequence with equal angular intervals in the angular domain.

[0055] All selected vibration sensor data are analyzed based on their corresponding instantaneous phase. The signals are sorted to form a vibration signal sequence with equal angular intervals in the angular domain. , Since each vibration data point uniquely corresponds to the instantaneous mechanical phase represented by the encoder trigger edge, this signal can be directly used for subsequent angular domain analysis without the need for interpolation calculations.

[0056] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: (1) In this invention, by constructing a data acquisition channel that shares a synchronous clock source with the rotary encoder and vibration sensor, and by directly filtering the oversampled vibration data based on encoder edge triggering, angular domain sampling from the source is achieved. This fundamental change eliminates the need for any form of interpolation calculation in the angular domain sampling process of the vibration signal. It directly avoids the signal amplitude attenuation and phase distortion introduced by the inherent prediction and fitting characteristics of interpolation algorithms, and can completely preserve the high-frequency components and instantaneous impact characteristics in the original vibration signal, significantly improving the fidelity of the angular domain vibration signal, and providing a more realistic and reliable data foundation for subsequent accurate fault diagnosis.

[0057] (2) In this invention, the method utilizes a hardware synchronization and triggering mechanism to replace the complex software algorithm in traditional order tracking technology. The system does not need to perform tedious instantaneous rotational speed calculations, nor does it need to perform computationally intensive interpolation and resampling operations. This greatly simplifies the overall process from data acquisition to angular domain signal generation and reduces the dependence on microprocessor computing performance. The direct result is a significant improvement in data processing efficiency, enabling faster completion of vibration state analysis of rotating machinery, effectively supporting online real-time monitoring of equipment and rapid early warning of faults, and improving the response speed and practicality of the entire monitoring system.

[0058] (3) In this invention, by precisely synchronizing the clock and aligning the timestamps, and by combining the minimum oversampling rate set for vibration data acquisition according to a specific formula, it is ensured that at the encoder triggering time of each characterizing angle, the closest real vibration data point in time can always be found from the cache. This "hardware synchronization screening" mechanism not only ensures the equiangular interval characteristics of the angular domain sampling points, but also ensures that each data point originates from an actual physical sampling, rather than mathematical derivation. This method fundamentally eliminates the influence of algorithm selection and parameter settings on the analysis results, ensuring the consistency and repeatability of analysis results between different measurements and different devices, while taking into account both signal accuracy and system processing efficiency, providing a new technical path for achieving highly reliable and efficient intelligent diagnosis of rotating machinery.

[0059] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

[0060] The following points need to be explained: (1) The accompanying drawings of the embodiments of the present invention only involve the structures involved in the embodiments of the present invention. Other structures can refer to the general design.

[0061] (2) Where there is no conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other to obtain new embodiments.

[0062] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. The scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for angular domain sampling of vibration signals from rotating machinery, characterized in that, The application relates to a method for synchronizing data acquisition channels of a rotary encoder and a vibration sensor. A synchronous data acquisition channel of the rotary encoder and the vibration sensor is established by sharing a clock source; On the basis of the synchronous data acquisition channel, a first-in-first-out (FIFO) buffer of vibration sensor data is established, which is aligned with the time stamp of the encoder channel; On the basis of oversampling of the vibration sensor data, angular domain sampling data screening triggered by the edge of the rotary encoder is realized; The screened vibration sensor data is sorted according to instantaneous angle values to form angular domain sampling vibration signals.

2. The method of claim 1, wherein, The application relates to a method for synchronizing data acquisition channels of a rotary encoder and a vibration sensor. The application relates to a method for synchronizing data acquisition channels of a rotary encoder and a vibration sensor.

3. The method of claim 1, wherein, The data acquisition channel of the rotary encoder comprises an encoder, a first-order RC filter, an optical coupling isolation and a micro control unit (MCU); The MCU is configured to directly form effective data time stamps by using the edge trigger of the rotary encoder. The application relates to a method for synchronizing data acquisition channels of a rotary encoder and a vibration sensor.

4. The method of claim 1, wherein, The application relates to a method for synchronizing data acquisition channels of a rotary encoder and a vibration sensor. The vibration sensor data acquisition channel is composed of an analog-to-digital conversion AD, a first-in-first-out buffer FIFO, and an MCU, and the minimum value of the sampling frequency is The calculation is performed by the following formula: wherein is the number of encoder lines, is the number of revolutions per minute of the rotating machine under test.

5. The method of claim 1, wherein, The application relates to a method for synchronizing data acquisition channels of a rotary encoder and a vibration sensor. The common clock source comprises a first crystal oscillator and a second crystal oscillator; Let the time of the n-th trigger edge signal of the rotary encoder be , which corresponds to the instantaneous phase of the measured rotary machine ; when a trigger edge signal is generated, the sample time stamp closest to the vibration sensor data at the instant of the phase corresponding vibration signal data is sieved from the FIFO.

6. The method of claim 5, wherein, The first crystal oscillator is used for providing a core working clock for the MCU, and the second crystal oscillator is specially used for generating the synchronous time stamp. The time-sequentially stored data segments in the vibration sensor data FIFO, whose first register time stamp sequence is ; For encoder trigger time Seeking satisfaction The interval is defined, and from the FIFO data corresponding to that interval, the sample time stamp closest to the defined interval is selected. Vibration data Forming corner domain sampling data pairs .

7. The method of claim 1, wherein, The timer of the MCU enables an encoder mode, counts the pulse edges of the encoder and captures the rising edges of the encoder signals in real time by using an input capture function to record the trigger time. The MCU adds fixed interval acquisition time stamps to each AD conversion value to form time stamped data and sequentially stores the time stamped data into the FIFO. The application relates to a method for synchronizing data acquisition channels of a rotary encoder and a vibration sensor.

8. The method of claim 3, wherein, ​ ​ 9. The method of claim 4, wherein, ​ ​ 10. The method of claim 5, wherein, ​ All the screened vibration sensor data are sorted according to their corresponding instantaneous phases to obtain the angular domain equiangular interval vibration signal sequence.

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