Method and system for estimating rotating speed of rotating equipment based on quantitative analysis, and electronic equipment

Abstract

The invention relates to the technical field of rotating equipment rotating speed estimation, and discloses a rotating equipment rotating speed estimation method and system based on quantitative analysis and electronic equipment, and the method comprises the steps: collecting a vibration signal of rotating equipment, and obtaining an envelope demodulation spectrum through band-pass filtering and envelope demodulation processing; k frequencies with the highest amplitude are selected from the spectrum, and K candidate fundamental frequencies are calculated according to the harmonic interval and the corresponding order of the K frequencies; calculating a frequency deviation degree and an amplitude contribution degree index of a multi-order harmonic wave for each candidate fundamental frequency to obtain a single-order harmonic wave evaluation value, and introducing a penalty coefficient for weighted summation to obtain a comprehensive evaluation index; and selecting the candidate fundamental frequency with the highest index as an estimated fundamental frequency, and calculating to obtain an estimated rotating speed. The method realizes quantitative analysis of rotating speed estimation, avoids subjectivity of a traditional method, integrates multi-dimensional indexes to improve accuracy and reliability under complex working conditions, does not need to deploy a rotating speed sensor additionally, reduces cost and installation difficulty, and is suitable for monitoring various rotating devices.

Description

Technical Field

[0001] This invention relates to the field of rotating equipment speed estimation technology, and specifically to a rotating equipment speed estimation method, system, and electronic equipment based on quantitative analysis. Background Technology

[0002] The core sources of escalator failures are concentrated in rotating equipment such as motors, bearings, gearboxes, and drive shafts. Speed ​​information is the key basic data for fault detection and diagnosis of such rotating equipment. Whether it is bearing wear, abnormal gear meshing, or motor imbalance, the characteristic signals are directly related to the actual speed of the equipment. Accurate speed data can greatly improve the accuracy of fault location and diagnostic efficiency.

[0003] However, in practical applications, due to limitations in installation space, cost control, and the difficulty of equipment modification, it is impossible to deploy dedicated speed sensors on a large scale for all rotating parts. Therefore, it is necessary to indirectly estimate the speed using existing signals (such as vibration and current signals). Existing speed estimation schemes are mostly based on the frequency domain analysis approach: first, a candidate frequency range is set, and after performing a frequency domain transformation on the vibration or current signal, the frequency with the largest amplitude within the reference range is selected as the fundamental frequency to calculate the speed.

[0004] However, this type of method has obvious drawbacks: First, the fundamental frequency identification relies on expert experience for qualitative judgment, which is highly subjective and can easily lead to deviations in results due to different personnel operation; Second, it only focuses on the first harmonic and ignores the information of multiple harmonics, which leads to the randomness of the fundamental frequency selection and makes it impossible to quantify the reliability of the results; Third, low-frequency interference, high-frequency noise and complex electromagnetic interference under actual working conditions can easily mask the true fundamental frequency characteristics, resulting in poor stability and high error rate of speed estimation results, which makes it difficult to meet the actual needs of high reliability monitoring of escalators. Summary of the Invention

[0005] To address the problems of existing rotational speed estimation methods for rotating equipment based on vibration or current signals, which rely on qualitative judgments based on expert experience, consider only the first harmonic, are susceptible to interference leading to highly subjective results, difficulty in quantifying reliability, and poor stability, this invention provides a rotational speed estimation method, system, and electronic equipment based on quantitative analysis. This method quantifies the speed identification process, significantly reduces reliance on expert experience, and considers multi-order harmonic information, improving the robustness and stability of the identification results. Practical application has shown significant results, substantially improving the accuracy of speed estimation.

[0006] In a first aspect, the present invention provides a method for estimating the rotational speed of a rotating device based on quantitative analysis, comprising: Vibration signals generated during the operation of rotating equipment are collected, and the vibration signals are subjected to bandpass filtering and envelope demodulation to obtain the envelope demodulation spectrum. K frequencies with the highest amplitude are selected from the envelope demodulation spectrum, where K is a preset positive integer. K candidate fundamental frequencies are calculated based on the harmonic interval to which each frequency belongs and its corresponding harmonic order. For each candidate fundamental frequency, calculate its frequency deviation index and amplitude contribution index at multiple harmonic orders. Based on the frequency deviation index and amplitude contribution index, the single-order harmonic evaluation value of each harmonic is calculated, and then a penalty coefficient is introduced to weight and sum the single-order harmonic evaluation values ​​to obtain the comprehensive evaluation index value of the candidate fundamental frequency. The candidate fundamental frequency with the highest comprehensive evaluation index is selected as the estimated fundamental frequency, and the estimated rotational speed of the rotating equipment is calculated based on the estimated fundamental frequency.

[0007] The rotating equipment speed estimation method based on quantitative analysis provided in this invention obtains the envelope demodulation spectrum by processing the vibration signal, generates candidate fundamental frequencies from the K frequencies with the highest amplitude, and then calculates a comprehensive evaluation index by combining the frequency deviation, amplitude contribution, and penalty coefficient of multiple harmonics. Finally, the optimal candidate fundamental frequency is selected to calculate the rotational speed. This process achieves quantitative analysis of rotational speed estimation, avoids the subjectivity of traditional methods that rely on experience, and improves the accuracy and reliability of rotational speed estimation under complex operating conditions by integrating multi-dimensional indicators. It eliminates the need for additional rotational speed sensors, reducing costs and installation difficulty, and is suitable for efficient monitoring of various rotating equipment.

[0008] In one optional implementation, the bandpass filtering and envelope demodulation processing of the vibration signal to obtain the envelope demodulation spectrum includes: Based on the operating characteristics of the rotating equipment and the frequency band characteristics of the vibration signal, low-frequency cutoff frequency and high-frequency cutoff frequency are set to perform bandpass filtering on the collected vibration signal; The filtered signal is subjected to Hilbert transform to generate the corresponding analytic signal, and the envelope signal is obtained by calculating the absolute value of the analytic signal. The envelope signal is subjected to a discrete Fourier transform to obtain the envelope demodulation spectrum that characterizes the low-frequency fundamental frequency and its harmonic features.

[0009] This invention employs targeted cutoff frequencies for bandpass filtering, effectively suppressing interference and noise in irrelevant frequency bands. The envelope signal is extracted using Hilbert transform and then demodulated using Fourier transform to obtain the envelope demodulation spectrum, accurately preserving the low-frequency fundamental frequency and harmonic characteristics. This processing enhances the prominence of the effective signal, reduces noise interference in subsequent analysis, lays a high-quality data foundation for the accurate extraction of candidate fundamental frequencies, and improves the anti-interference capability and signal utilization of the entire speed estimation method.

[0010] In one optional implementation, the step of selecting the K frequencies with the highest amplitude from the envelope demodulation spectrum, where K is a preset positive integer; and calculating K candidate fundamental frequencies based on the harmonic interval to which each frequency belongs and its corresponding harmonic order, including: The rated rotational frequency is calculated based on the rated rotational speed of the rotating equipment, and the envelope demodulation spectrum is divided into M harmonic intervals according to the rated rotational frequency. Each interval corresponds to the frequency range of the 1st to Mth harmonics. The K frequencies with the highest amplitudes are selected from the envelope demodulation spectrum. The harmonic order of each frequency is determined according to the harmonic interval in which it is located. The frequency is divided by the corresponding harmonic order to obtain the K candidate fundamental frequencies.

[0011] This invention divides the harmonic range based on the rated speed, making the correspondence between frequency and harmonic order more closely match the actual operating characteristics of the equipment and avoiding the blindness of order judgment. By selecting the K frequencies with the highest amplitude from the envelope demodulation spectrum and calculating candidate fundamental frequencies, it not only focuses on strong characteristic signals but also expands the selection range of the optimal solution through multiple candidate values. This method reduces the randomness of selecting a single frequency, makes the candidate fundamental frequencies more representative, and provides a reliable analytical object for subsequent comprehensive evaluation.

[0012] In one optional implementation, the frequency deviation index is used to quantify the degree of deviation between the current frequency value and the candidate fundamental frequency, and is calculated using the following formula:

[0013] In the formula, Indicates the frequency to be evaluated. Indicates the candidate fundamental frequency. Indicates the harmonic order. This represents the proportion of the relative frequency error. Indicates the absolute error frequency. This index represents the frequency deviation of the current frequency relative to the candidate fundamental frequency. A larger index value indicates a higher probability that the current frequency is a harmonic of the candidate fundamental frequency. The range of the index value is... .

[0014] In this embodiment of the invention, the frequency deviation index quantifies the deviation between the frequency to be evaluated and the candidate fundamental frequency using an exponential function. Combining the relative error ratio α and the absolute error frequency β, it considers both the relative and absolute frequency deviations, making the deviation assessment more closely reflect actual operating conditions. The index value is within... The interval directly reflects the probability of the frequency being a harmonic, providing a scientific quantitative basis for subsequent evaluation value calculations and improving the objectivity and accuracy of fundamental frequency judgment.

[0015] In one optional implementation, the amplitude contribution index is calculated based on the amplitude corresponding to the frequency, and is used to quantitatively evaluate the credibility of the candidate fundamental harmonic at that amplitude level. It is calculated using the following formula:

[0016] In the formula, Indicates the harmonic order. This indicates the amplitude corresponding to the current frequency. This represents the highest amplitude in the spectrum. It is used to characterize the importance of different order harmonic amplitudes. When the amplitude remains constant, the lower the order, the higher the importance. This indicates the effective amplitude ratio.

[0017] The amplitude contribution index in this embodiment of the invention, by introducing the order weight parameter C1 and the effective amplitude ratio C2, not only reflects the higher importance of lower-order harmonic amplitudes, but also limits the effective amplitude range by comparing it with the highest amplitude. The use of a min function ensures that the index value is within the [0,1] interval, quantifying the reliability of amplitude as a harmonic, overcoming the limitations of relying solely on frequency deviation, making the evaluation dimensions more comprehensive, and improving the reliability of fundamental frequency selection.

[0018] In one optional implementation, the comprehensive evaluation index value is calculated using the following formula:

[0019] In the formula, This represents the penalty coefficient, with a value range of [value missing]. , Indicates the maximum harmonic order. Indicates the first The single-order harmonic evaluation value of a harmonic is calculated using the following formula:

[0020] In the formula, Indicates the first The frequency deviation index value of the first harmonic. Indicates the first The amplitude contribution index value of the first harmonic.

[0021] The single-order harmonic evaluation value provided by this invention integrates evaluation information from two dimensions by multiplying the frequency deviation and amplitude contribution. The comprehensive evaluation index introduces a penalty coefficient γ to weight higher-order harmonics, highlighting the dominant role of lower-order harmonics and conforming to the actual distribution law of harmonic characteristics. This calculation method achieves the orderly integration of multi-order harmonic information, enabling the comprehensive evaluation index to more accurately reflect the authenticity of candidate fundamental frequencies, ensuring that the final estimated fundamental frequency is optimal, and further improving the accuracy of speed estimation.

[0022] Secondly, embodiments of the present invention provide a rotating equipment speed estimation system based on quantitative analysis, comprising: The signal processing module is used to acquire vibration signals generated during the operation of the rotating equipment, and to perform bandpass filtering and envelope demodulation on the vibration signals to obtain the envelope demodulation spectrum. The candidate fundamental frequency generation module is used to select the K frequencies with the highest amplitude from the envelope demodulation spectrum, where K is a preset positive integer; and to calculate the K candidate fundamental frequencies based on the harmonic interval to which each frequency belongs and its corresponding harmonic order. The index calculation module is used to calculate the frequency deviation index and amplitude contribution index of each candidate fundamental frequency at multiple harmonic orders. The comprehensive evaluation module is used to calculate the single-order harmonic evaluation value of each harmonic based on the frequency deviation index and amplitude contribution index, and then introduce a penalty coefficient to perform a weighted summation of the single-order harmonic evaluation values ​​to obtain the comprehensive evaluation index value of the candidate fundamental frequency. The rotational speed estimation module is used to select the candidate fundamental frequency with the highest comprehensive evaluation index as the estimated fundamental frequency, and to calculate the estimated rotational speed of the rotating equipment based on the estimated fundamental frequency.

[0023] Thirdly, the present invention provides an electronic device, comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the rotating equipment speed estimation method based on quantitative analysis described in the first aspect or any corresponding embodiment thereof.

[0024] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the quantitative analysis-based method for estimating the rotational speed of a rotating device as described in the first aspect or any corresponding embodiment thereof.

[0025] Fifthly, the present invention provides a computer program product, including computer instructions for causing a computer to execute the quantitative analysis-based method for estimating the rotational speed of a rotating device as described in the first aspect or any corresponding embodiment thereof. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a flowchart illustrating a method for estimating the rotational speed of a rotating device based on quantitative analysis according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the envelope demodulation spectrum in an application scenario according to an embodiment of the present invention; Figure 3 This is a structural block diagram of a rotating equipment speed estimation system based on quantitative analysis according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0030] Currently, speed estimation methods based on vibration signals mainly rely on the analysis of the spectrum or envelope demodulation spectrum, calculating the speed by finding the frequency component with the largest amplitude as the fundamental frequency. While these methods do not require additional sensors, they face significant limitations under complex real-world conditions: First, the fundamental frequency identification process heavily relies on expert experience, employing a qualitative analysis approach that is highly subjective and inconsistent; second, these methods typically consider only a single harmonic component, neglecting the collaborative verification of multiple harmonics, making the results susceptible to noise and interference frequencies, resulting in insufficient stability; furthermore, existing methods lack a quantitative evaluation mechanism for the reliability of the identification results, making it difficult to guarantee estimation accuracy in practical applications. These shortcomings limit the widespread application of existing technologies in industrial settings, necessitating a more objective, robust, and quantifiable speed estimation method.

[0031] Based on this, this invention provides an embodiment of a rotating equipment speed estimation method based on quantitative analysis. It calculates quantitative indicators according to each consideration item in the speed identification process, improving the reliability of the results and significantly reducing reliance on expert experience. It also considers multi-order harmonic information, effectively reducing the randomness caused by single harmonics and improving the robustness and stability of the identification results. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here. Figure 1 This is a flowchart of a rotating equipment speed estimation method based on quantitative analysis according to an embodiment of the present invention, as shown below. Figure 1 As shown, the process includes the following steps: Step S1: Collect the vibration signal generated during the operation of the rotating equipment, and perform bandpass filtering and envelope demodulation processing on the vibration signal to obtain the envelope demodulation spectrum.

[0032] Specifically, embodiments of the present invention collect vibration waveform data generated during the operation of rotating equipment. Further processing of the vibration signal includes bandpass filtering and envelope demodulation. Bandpass filtering is achieved by setting a set of low-frequency cutoff frequencies. and high frequency cutoff frequency Bandpass filtering effectively removes low-frequency interference and high-frequency noise from the original signal, improving the signal-to-noise ratio. It suppresses signals below low frequencies and above high frequencies, retaining only signals within two cutoff frequency ranges. Envelope demodulation is a method to demodulate modulated low-frequency components in the high-frequency resonant band. Since the fundamental frequency and its harmonics appear as sidebands of the high-frequency resonant frequency most of the time, they are difficult to distinguish in the low-frequency band. Therefore, envelope demodulation is used to demodulate the low-frequency fundamental frequency and its harmonics, obtaining fundamental frequency information with more distinct frequency characteristics.

[0033] Furthermore, the process of performing bandpass filtering and envelope demodulation on the vibration signal to obtain the envelope demodulation spectrum in this embodiment of the invention includes the following steps: Step S11: Based on the operating characteristics of the rotating equipment and the frequency band characteristics of the vibration signal, set the low-frequency cutoff frequency and the high-frequency cutoff frequency to perform bandpass filtering on the collected vibration signal.

[0034] Specifically, the energy spectrum is obtained by performing a frequency domain transformation on the original vibration signal, the range in which the energy is most concentrated is found, and then the maximum and minimum frequencies within this range are used as the cutoff frequencies of the bandpass filter.

[0035] Step S12: Perform Hilbert transform on the filtered signal to generate the corresponding analytic signal, and obtain the envelope signal by calculating the absolute value of the analytic signal.

[0036] Specifically, the formula for calculating the envelope signal using the Hilbert transform is shown below.

[0037]

[0038] In the formula, This is the filtered vibration signal. The imaginary unit, Represents the Hilbert transform operator. for The analytic signal, the absolute value of the analytic signal is the envelope signal. .

[0039] Step S13: Perform a discrete Fourier transform on the envelope signal to obtain the envelope demodulation spectrum characterizing the low-frequency fundamental frequency and its harmonics.

[0040] The envelope demodulation spectrum is obtained by performing a Fourier transform on the envelope signal. The formula for the Fourier transform is shown below.

[0041]

[0042] In the formula, For the first Complex spectral values ​​at each frequency point This is a frequency index, and its value range is: .

[0043] This invention employs targeted cutoff frequencies for bandpass filtering, effectively suppressing interference and noise in irrelevant frequency bands. The envelope signal is extracted using Hilbert transform and then demodulated using Fourier transform to obtain the envelope demodulation spectrum, accurately preserving the low-frequency fundamental frequency and harmonic characteristics. This processing enhances the prominence of the effective signal, reduces noise interference in subsequent analysis, lays a high-quality data foundation for the accurate extraction of candidate fundamental frequencies, and improves the anti-interference capability and signal utilization of the entire speed estimation method.

[0044] Step S2: Select the K frequencies with the highest amplitude from the envelope demodulation spectrum, and calculate the candidate fundamental frequency according to the harmonic interval of each frequency.

[0045] Specifically, the embodiments of the present invention are based on the rated speed of the rotating equipment. Calculate the rated frequency ,Right now The envelope demodulation spectrum is divided into M harmonic intervals based on the rated switching frequency, with each interval corresponding to the frequency range of the 1st to Mth harmonics; for example, interval 1 is... , representing the range of values ​​for the first harmonic; interval 2 is , indicating the range of values ​​for the second harmonic; interval for ,express The range of values ​​for subharmonics.

[0046] Furthermore, the K frequencies with the highest amplitudes are selected from the envelope demodulation spectrum. The harmonic order of each frequency is determined based on its harmonic range. The frequency is then divided by its corresponding harmonic order to obtain K candidate fundamental frequencies. In this embodiment, the value of K is determined based on the actual data, preferably among the top 5% of frequencies with the highest amplitudes in the envelope demodulation spectrum (i.e., the value of k is the number of spectral lines in the envelope demodulation spectrum multiplied by 0.05). This ensures that the candidate values ​​include the true fundamental frequency while avoiding an increase in computational load due to too many candidate values.

[0047] Step S3: For each candidate fundamental frequency, calculate its frequency deviation index and amplitude contribution index at multiple harmonic orders.

[0048] Specifically, the frequency deviation index used in this embodiment of the invention is used to quantify the degree of deviation between the current frequency value and the candidate fundamental frequency, and is calculated using the following formula:

[0049] In the formula, Indicates the frequency to be evaluated. Indicates the candidate fundamental frequency. Indicates the harmonic order. This represents the proportion of the relative frequency error. Indicates the absolute error frequency. This index represents the frequency deviation of the current frequency relative to the candidate fundamental frequency. A larger index value indicates a higher probability that the current frequency is a harmonic of the candidate fundamental frequency. The range of the index value is... .

[0050] Amplitude contribution index It is calculated based on the amplitude corresponding to the frequency, and is used to quantitatively evaluate the credibility of the frequency as a candidate fundamental harmonic at that amplitude level. It is calculated using the following formula:

[0051] In the formula, Indicates the harmonic order. This indicates the amplitude corresponding to the current frequency. This represents the highest amplitude in the spectrum. This means choosing the smaller value from two numbers. index This is used to characterize the importance of different order harmonic amplitudes. With the amplitude remaining constant, the lower the order, the higher the importance. It is recommended to choose 0.2 as the initial value. After accumulating labeled data, it can be... Optimize within the interval; This parameter represents the effective amplitude proportion. In the envelope demodulation spectrum, the frequency component whose amplitude reaches a certain proportion of its maximum value is considered the effective component. It is recommended to select [the appropriate parameter]. The initial value is 0.7. After accumulating labeled data, it can be optimized within the range of [0.5, 1] ​​for the amplitude contribution index. The final calculation result ranges from [0,1]. The closer it is to 1, the higher the reliability of the frequency as the amplitude of the corresponding harmonic.

[0052] This invention calculates frequency deviation and amplitude contribution indices for each candidate fundamental frequency at multiple harmonic orders. This allows for multi-dimensional quantitative verification of the candidate fundamental frequency's rationality: First, the frequency deviation index accurately quantifies the degree of deviation between the evaluated frequency and each harmonic of the candidate fundamental frequency. Combined with relative and absolute error parameters, it objectively reflects the likelihood that the frequency belongs to the candidate fundamental frequency harmonics, avoiding the subjectivity of approximate judgments based solely on frequency values. Second, the amplitude contribution index quantifies the amplitude credibility of different harmonic orders through order weights and amplitude ratios, highlighting the importance of lower-order harmonics and compensating for the one-sidedness of relying solely on frequency characteristics. The combination of these two indices provides a comprehensive evaluation of the candidate fundamental frequency in both frequency matching and amplitude effectiveness, offering a solid quantitative basis for subsequent comprehensive evaluation. This reduces misjudgments caused by single-order or single-index analysis, significantly improving the scientific rigor and reliability of candidate fundamental frequency selection.

[0053] Step S4: Based on the frequency deviation index and amplitude contribution index, calculate the single-order harmonic evaluation value of each harmonic, and then introduce a penalty coefficient to perform a weighted summation of the single-order harmonic evaluation values ​​to obtain the comprehensive evaluation index value of the candidate fundamental frequency.

[0054] Specifically, the comprehensive evaluation index value It is calculated using the following formula:

[0055] In the formula, This represents the penalty coefficient, with a value range of [value missing]. , Indicates the maximum harmonic order. Indicates the first The single-order harmonic evaluation value of a harmonic is calculated using the following formula:

[0056] In the formula, Indicates the first The frequency deviation index value of the first harmonic. Indicates the first The amplitude contribution index value of the first harmonic.

[0057] The comprehensive evaluation index provided in this embodiment of the invention integrates the quantitative information of multiple harmonics to form a global evaluation standard for candidate fundamental frequencies. It retains the effective characteristics of each harmonic and avoids the misleading information of irrelevant or interfering information through scientific weighting, making the comparison of the merits of candidate fundamental frequencies more accurate. It provides a reliable basis for screening the optimal estimated fundamental frequency and further improves the stability and accuracy of speed estimation. Step S5: Select the candidate fundamental frequency with the highest comprehensive evaluation index as the estimated fundamental frequency, and calculate the estimated rotational speed of the rotating equipment based on the estimated fundamental frequency.

[0058] Specifically, the comprehensive evaluation index is a global quantitative integration of the frequency matching degree, amplitude reliability, and order rationality of the candidate fundamental frequency under multiple harmonics. Its value directly reflects the degree of fit between the candidate fundamental frequency and the actual fundamental frequency of the equipment. Selecting the candidate fundamental frequency corresponding to the highest value can minimize the random errors caused by single-frequency or local feature analysis, ensuring that the selected estimated fundamental frequency is the optimal solution under multi-dimensional verification. From multiple candidate fundamental frequencies, the comprehensive evaluation index is selected. The highest value is taken as the final estimated fundamental frequency; then, through the conversion relationship of "rotation speed = estimated fundamental frequency × 60" (fundamental frequency is in Hz, rotation speed is in r / min), the estimated rotation speed of the rotating equipment is obtained.

[0059] The rotational speed calculated based on this estimated fundamental frequency not only inherits the scientific rigor of previous multi-index analyses but also establishes a precise correlation with the actual rotational speed through a direct conversion of "fundamental frequency × 60." The final result balances anti-interference capability and quantitative reliability. Compared to traditional rotational speed estimation methods that rely on experience or single features, this process is entirely based on objective index selection, significantly reducing human error, improving the accuracy and consistency of rotational speed estimation under complex operating conditions, and enhancing the robustness and stability of the identification results. This provides reliable basic data support for fault diagnosis and condition monitoring of rotating equipment.

[0060] In one application example, vibration data of the motor output shaft was collected, with a sampling frequency of 12000 Hz and 24000 data sampling points. The actual rotational speed of the motor output shaft was 1728 r / min. Figure 2 This represents the candidate fundamental frequency and its harmonics with the highest envelope demodulation spectrum and comprehensive evaluation index value. The candidate fundamental frequency falls within the range of the third harmonic; therefore, the candidate fundamental frequency is... The calculated estimated rotational speed is 1729.8 r / min, which has an error of 1.8 r / min compared to the actual rotational speed.

[0061] This invention also provides a rotating equipment speed estimation system based on quantitative analysis, such as... Figure 3 As shown, it includes: The signal processing module 31 is used to collect the vibration signal generated during the operation of the rotating equipment, and to perform bandpass filtering and envelope demodulation processing on the vibration signal to obtain the envelope demodulation spectrum. The candidate fundamental frequency generation module 32 is used to select the K frequencies with the highest amplitude from the envelope demodulation spectrum, where K is a preset positive integer; and to calculate the K candidate fundamental frequencies according to the harmonic interval to which each frequency belongs and its corresponding harmonic order. The index calculation module 33 is used to calculate the frequency deviation index and amplitude contribution index of each candidate fundamental frequency under multiple harmonic orders. The comprehensive evaluation module 34 is used to calculate the single-order harmonic evaluation value of each harmonic based on the frequency deviation index and the amplitude contribution index, and then introduce a penalty coefficient to perform a weighted summation of the single-order harmonic evaluation values ​​to obtain the comprehensive evaluation index value of the candidate fundamental frequency. The rotational speed estimation module 35 is used to select the candidate fundamental frequency with the highest comprehensive evaluation index as the estimated fundamental frequency, and calculate the estimated rotational speed of the rotating equipment based on the estimated fundamental frequency.

[0062] In an optional embodiment, the signal processing module 31 includes: The bandpass filter processing unit is used to set the low-frequency cutoff frequency and high-frequency cutoff frequency to perform bandpass filter processing on the collected vibration signal according to the operating characteristics of the rotating equipment and the frequency band characteristics of the vibration signal. The envelope signal acquisition unit is used to perform Hilbert transform on the filtered signal to generate the corresponding analytic signal, and obtain the envelope signal by calculating the absolute value of the analytic signal. The envelope demodulation spectrum acquisition unit is used to perform discrete Fourier transform on the envelope signal to obtain the envelope demodulation spectrum characterizing the low-frequency fundamental frequency and its harmonic features.

[0063] In an optional embodiment, the candidate fundamental frequency generation module 32 includes: The harmonic interval division unit is used to calculate the rated rotational frequency based on the rated rotational speed of the rotating equipment, and divide the envelope demodulation spectrum of the rated rotational frequency into M harmonic intervals, each interval corresponding to the frequency range of the 1st to Mth order harmonics. The candidate fundamental frequency acquisition unit is used to select the K frequencies with the highest amplitude from the envelope demodulation spectrum, determine the corresponding harmonic order according to the harmonic interval in which each frequency is located, and divide the frequency by the corresponding harmonic order to obtain the K candidate fundamental frequencies.

[0064] In an optional embodiment, the frequency deviation index in the index calculation module 33 is used to quantify the degree of deviation between the current frequency value and the candidate fundamental frequency, and is calculated using the following formula:

[0065] In the formula, Indicates the frequency to be evaluated. Indicates the candidate fundamental frequency. Indicates the harmonic order. This represents the proportion of the relative frequency error. Indicates the absolute error frequency. This index represents the frequency deviation of the current frequency relative to the candidate fundamental frequency. A larger index value indicates a higher probability that the current frequency is a harmonic of the candidate fundamental frequency. The range of the index value is... .

[0066] In an optional embodiment, the amplitude contribution index in the index calculation module 33 is calculated based on the amplitude corresponding to the frequency, and is used to quantitatively evaluate the credibility of the candidate fundamental harmonic at that amplitude level. It is calculated using the following formula:

[0067] In the formula, Indicates the harmonic order. This indicates the amplitude corresponding to the current frequency. This represents the highest amplitude in the spectrum. index It is used to characterize the importance of different order harmonic amplitudes. When the amplitude remains constant, the lower the order, the higher the importance. This indicates the effective amplitude ratio.

[0068] In an optional embodiment, the comprehensive evaluation index value in the comprehensive evaluation module 34 is calculated using the following formula:

[0069] In the formula, This represents the penalty coefficient, with a value range of [value missing]. , Indicates the maximum harmonic order. Indicates the first The single-order harmonic evaluation value of a harmonic is calculated using the following formula:

[0070] In the formula, Indicates the first The frequency deviation index value of the first harmonic. Indicates the first The amplitude contribution index value of the first harmonic.

[0071] The rotating equipment speed estimation system based on quantitative analysis provided in this invention can execute the rotating equipment speed estimation method based on quantitative analysis provided in any embodiment of this invention, and has the corresponding functional modules and beneficial effects for executing the method. Further functional descriptions of the above modules and units are the same as in the corresponding embodiments described above, and will not be repeated here.

[0072] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0073] The following is a detailed reference. Figure 4 This diagram illustrates a structural schematic suitable for implementing an electronic device according to embodiments of the present invention. The electronic device may include a processor (e.g., a central processing unit, graphics processor, etc.) 401, which can perform various appropriate actions and processes based on a program stored in read-only memory (ROM) 402 or a program loaded from memory 408 into random access memory (RAM) 403. RAM 403 also stores various programs and data required for the operation of the electronic device. The processor 401, ROM 402, and RAM 403 are interconnected via bus 404. Input / output (I / O) interface 405 is also connected to bus 404.

[0074] Typically, the following devices can be connected to I / O interface 405: input devices 406 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, etc.; output devices 407 including, for example, liquid crystal displays (LCDs), speakers, etc.; memory devices 408 including, for example, magnetic tapes, hard disks, etc.; and communication devices 409. Communication device 409 allows electronic devices to exchange data via wireless or wired communication with other devices. Although Figure 4 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown, and more or fewer devices may be implemented or have instead.

[0075] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via a communication device 409, or installed from a memory 408, or installed from a ROM 402. When the computer program is executed by the processor 401, it performs the functions defined in the quantitative analysis-based rotating equipment speed estimation method of the embodiments of the present invention.

[0076] Figure 4 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of the present invention.

[0077] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the rotating equipment speed estimation method based on quantitative analysis shown in the above embodiments is implemented.

[0078] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0079] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for estimating the rotational speed of rotating equipment based on quantitative analysis, characterized in that, include: Vibration signals generated during the operation of rotating equipment are collected, and the vibration signals are subjected to bandpass filtering and envelope demodulation to obtain the envelope demodulation spectrum. K frequencies with the highest amplitude are selected from the envelope demodulation spectrum, where K is a preset positive integer. K candidate fundamental frequencies are calculated based on the harmonic interval to which each frequency belongs and its corresponding harmonic order. For each candidate fundamental frequency, calculate its frequency deviation index and amplitude contribution index at multiple harmonic orders. Based on the frequency deviation index and amplitude contribution index, the single-order harmonic evaluation value of each harmonic is calculated, and then a penalty coefficient is introduced to weight and sum the single-order harmonic evaluation values ​​to obtain the comprehensive evaluation index value of the candidate fundamental frequency. The candidate fundamental frequency with the highest comprehensive evaluation index is selected as the estimated fundamental frequency, and the estimated rotational speed of the rotating equipment is calculated based on the estimated fundamental frequency.

2. The method according to claim 1, characterized in that, The process of performing bandpass filtering and envelope demodulation on the vibration signal to obtain the envelope demodulation spectrum includes: Based on the operating characteristics of the rotating equipment and the frequency band characteristics of the vibration signal, low-frequency cutoff frequency and high-frequency cutoff frequency are set to perform bandpass filtering on the collected vibration signal; The filtered signal is subjected to Hilbert transform to generate the corresponding analytic signal, and the envelope signal is obtained by calculating the absolute value of the analytic signal. The envelope signal is subjected to a discrete Fourier transform to obtain the envelope demodulation spectrum that characterizes the low-frequency fundamental frequency and its harmonic features.

3. The method according to claim 1 or 2, characterized in that, The K frequencies with the highest amplitude are selected from the envelope demodulation spectrum, where K is a preset positive integer; Based on the harmonic range to which each frequency belongs and its corresponding harmonic order, K candidate fundamental frequencies are calculated, including: The rated rotational frequency is calculated based on the rated rotational speed of the rotating equipment, and the envelope demodulation spectrum is divided into M harmonic intervals according to the rated rotational frequency. Each interval corresponds to the frequency range of the 1st to Mth harmonics. The K frequencies with the highest amplitudes are selected from the envelope demodulation spectrum. The harmonic order of each frequency is determined according to the harmonic interval in which it is located. The frequency is divided by the corresponding harmonic order to obtain the K candidate fundamental frequencies.

4. The method according to claim 1, characterized in that, The frequency deviation index is used to quantify the degree of deviation between the current frequency value and the candidate fundamental frequency, and is calculated using the following formula: In the formula, Indicates the frequency to be evaluated. Indicates the candidate fundamental frequency. Indicates the harmonic order. This represents the proportion of the relative frequency error. Indicates the absolute error frequency. This index represents the frequency deviation of the current frequency relative to the candidate fundamental frequency. A larger index value indicates a higher probability that the current frequency is a harmonic of the candidate fundamental frequency. The range of the index value is... .

5. The method according to claim 1 or 4, characterized in that, The amplitude contribution index is calculated based on the amplitude corresponding to the frequency, and is used to quantitatively evaluate the credibility of a candidate fundamental harmonic at that amplitude level. It is calculated using the following formula: In the formula, Indicates the harmonic order. This indicates the amplitude corresponding to the current frequency. This represents the highest amplitude in the spectrum. It is used to characterize the importance of different order harmonic amplitudes. When the amplitude remains constant, the lower the order, the higher the importance. This indicates the effective amplitude ratio.

6. The method according to claim 5, characterized in that, The comprehensive evaluation index value is calculated using the following formula: In the formula, This represents the penalty coefficient, with a value range of [value missing]. , Indicates the maximum harmonic order. Indicates the first The single-order harmonic evaluation value of a harmonic is calculated using the following formula: In the formula, Indicates the first The frequency deviation index value of the first harmonic. Indicates the first The amplitude contribution index value of the first harmonic.

7. A rotating equipment speed estimation system based on quantitative analysis, characterized in that, include: The signal processing module is used to acquire vibration signals generated during the operation of the rotating equipment, and to perform bandpass filtering and envelope demodulation on the vibration signals to obtain the envelope demodulation spectrum. The candidate fundamental frequency generation module is used to select the K frequencies with the highest amplitude from the envelope demodulation spectrum, where K is a preset positive integer; Based on the harmonic interval to which each frequency belongs and its corresponding harmonic order, K candidate fundamental frequencies are calculated. The index calculation module is used to calculate the frequency deviation index and amplitude contribution index of each candidate fundamental frequency at multiple harmonic orders. The comprehensive evaluation module is used to calculate the single-order harmonic evaluation value of each harmonic based on the frequency deviation index and amplitude contribution index, and then introduce a penalty coefficient to perform a weighted summation of the single-order harmonic evaluation values ​​to obtain the comprehensive evaluation index value of the candidate fundamental frequency. The rotational speed estimation module is used to select the candidate fundamental frequency with the highest comprehensive evaluation index as the estimated fundamental frequency, and to calculate the estimated rotational speed of the rotating equipment based on the estimated fundamental frequency.

8. An electronic device, characterized in that, include: A memory and a processor are interconnected, the memory storing computer instructions, and the processor executing the computer instructions to perform the rotating equipment speed estimation method based on quantitative analysis as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to execute the rotating equipment speed estimation method based on quantitative analysis as described in any one of claims 1 to 6.

10. A computer program product, characterized in that, Includes computer instructions for causing a computer to execute the rotating equipment speed estimation method based on quantitative analysis as described in any one of claims 1 to 6.

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