Distribution box fault detection method, electronic equipment and readable storage medium
Through VMD decomposition, combined with arrangement entropy screening and denoising and multi-scale fuzzy entropy feature extraction, combined with GG clustering algorithm, the problems of insufficient feature extraction and poor clustering adaptability in traditional methods are solved, and the precise detection and classification of distribution box faults are realized.
Patent Information
- Application Number
- CN202510885361.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-30
- Publication Date
- 2025-07-29
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Traditional fault detection methods have insufficient feature extraction accuracy in distribution box fault recognition, poor clustering adaptability, and it is difficult to effectively separate noise from effective signals, resulting in low misjudgment and detection efficiency.
VMD decomposition combined with arrangement entropy screening and denoising, fault feature vectors are extracted through multi-scale fuzzy entropy, and fault classification, adaptive signal decomposition and feature optimization are used to use GG clustering algorithm.
It improves the accuracy and clustering accuracy of fault signal feature extraction, enhances the reliability and accuracy of fault detection, and adapts to signal processing under different fault states.
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Figure CN120387046A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of power system fault detection. Specifically, it relates to a method for detecting faults in a distribution box, an electronic device, and a readable storage medium. Background Art
[0002] As a key device in the power system, the operation state of the distribution box directly affects the safety and stability of the power grid. Traditional fault detection methods have significant limitations: First, at the signal processing level, due to the non-stationary and non-linear characteristics of the fault current signal, existing methods based on wavelet transform are difficult to effectively separate noise from effective signals, resulting in insufficient accuracy of feature extraction; Second, in terms of feature representation, relying on a single-scale entropy feature cannot comprehensively reflect the time-frequency domain complexity of the fault signal, easily causing misjudgment of fault modes; In addition, traditional clustering algorithms such as K-means are based on the assumption of spherical distribution, have poor adaptability to high-dimensional non-linear features, and slow iterative convergence speed, making it difficult to meet the requirements of real-time monitoring. These problems together lead to obvious bottlenecks in the recognition accuracy and detection efficiency of existing technologies for various types of faults in distribution boxes.
[0003] In view of the above problems, existing technologies urgently need to be improved. Summary of the Invention
[0004] The purpose of the present invention is to provide a method for detecting faults in a distribution box, an electronic device, and a readable storage medium, which has the advantages of improving the accuracy of fault signal feature extraction and clustering accuracy.
[0005] To achieve the above purpose, the present invention provides the following technical solutions: A method for detecting faults in a distribution box, comprising the following steps: S100. Collect current signals of the distribution box in different fault states; S200. Perform VMD decomposition on the transient fault current signals in different fault states to obtain IMF components in different frequency bands, calculate the permutation entropy of the IMF components, and denoise them when the permutation entropy is greater than or equal to a preset value, and do not denoise them when the permutation entropy is less than the preset value; calculate the fuzzy entropy values of each IMF for the denoised and non-denoised IMF components; S300. Use the fuzzy entropy values as fault feature vectors, and cluster the fault feature vectors through the GG clustering algorithm to identify different fault types.
[0006] Further, the present application also proposes that when determining the number K of IMF components, the value of K is initialized, and the Euclidean distance between each IMF component and the probability density function of the original signal is calculated. The two IMFs with the largest Euclidean distance increment are used as the boundaries, and several components with smaller Euclidean distances are selected as effective modal classifications and reconstructed. Then, the signal-to-noise ratio between the original signal and the reconstructed signal is solved, and the above steps are repeated with K increased by 1. The value of K for VMD decomposition when the signal-to-noise ratio of the reconstructed signal is the highest is selected as the optimal value of K.
[0007] Further, the present application also proposes that after determining the value of K, the IMF components under the current value of K are selected, and the IMFs with permutation entropy greater than or equal to the preset value are selected for denoising, and the denoising method is wavelet threshold denoising.
[0008] Further, the present application also proposes that when calculating the fuzzy entropy for each IMF component, for the IMF component sequence Construct a multi-scale coarse-grained sequence , is the sequence length, and its formula is as follows: In the above formula , represents the scale factor. For a given the original sequence is segmented into coarse-grained vectors of length ; subsequently, for each scale of the coarse-grained sequence calculate the fuzzy entropy.
[0009] Further, the present application also proposes that the multi-scale fuzzy entropy is: ; its mean value , k = 1, 2, … n; calculate its variance according to the fuzzy entropy, and the formula is: , arrange the variances in descending order, and select the fuzzy entropies of the first Z scales as the final features to be input into the GG clustering algorithm.
[0010] Further, the present application also proposes that the sample set of the selected fuzzy entropy is as the feature input, where there are d features in the set element in, then , let the clustering center vector of set Y be , and let the membership matrix be: , where c is the number of clustering centers; , represents the membership degree of the b-th sample to the a-th class, where , by iterating (U, V), the objective function J is minimized, where the expression of J is: , (1) In the above formula: M is the weighted exponent, generally taken as 2, It is the distance measure to be calculated during clustering.
[0011] Furthermore, this application also proposes that the clustering algorithm is as follows: It also includes setting a termination tolerance e > 0, randomly initializing the membership matrix as U, and then calculating the cluster centers, and its formula is: , where l is an integer and l > 1 in the above formula; calculating the maximum likelihood estimation distance measure, and the calculation formula is: In the above formula is the covariance matrix of the i-th cluster, is the prior probability that the i-th cluster is selected; updating the membership degree matrix U, and it is: ; when is satisfied, then terminate the iteration. If the condition is not met, that is, let l = l + 1, and continue to iterate V and U until is satisfied, so that the function J obtains the minimum value.
[0012] Furthermore, this application also proposes that where ; .
[0013] The present invention also provides an electronic device, including a memory and a processor. A computer program is stored in the memory, and the processor is configured to run the computer program to execute the distribution box fault detection method.
[0014] The present invention also provides a readable storage medium, on which a program is stored. When the program is executed by a processor, the distribution box fault detection method is implemented.
[0015] Advantages of the present invention: A distribution box fault detection method, an electronic device and a readable storage medium provided by this application, through VMD decomposition combined with permutation entropy screening for denoising, and extracting fault feature vectors based on multi-scale fuzzy entropy, and using the GG clustering algorithm to achieve fault classification, solve the problems of low feature extraction accuracy and poor clustering adaptability of traditional methods, and have the advantages of improving the accuracy of fault signal feature extraction and clustering accuracy. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic flow chart of an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS
[0017] The technical solutions in the present application will be clearly and completely described below with reference to the accompanying drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the present application described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application claimed, but merely represents the selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts fall within the scope of protection of the present application.
[0018] It should be noted that: Similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, the terms "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.
[0019] In the process of traditional distribution box fault detection, the processing of non-stationary transient current signals faces the problems of mode mixing and noise interference. The decomposition algorithm with fixed parameters is difficult to adapt to the dynamic changes of the signal frequency domain characteristics under different fault states, resulting in the inability to effectively separate the effective signal components from the noise. At the same time, the single-scale entropy feature extraction method has a single characterization dimension for signal complexity and cannot fully reflect the differential characteristics of fault modes on multiple time scales.
[0020] For example, in the distribution box short-circuit fault detection scenario based on current signal analysis, the current signal collected by the sensor contains high-frequency arc noise and transient attenuation components. When using traditional wavelet transform for signal decomposition, the fixed basis function and decomposition layer number result in mode mixing in the high-frequency band, and the noise component and the true fault feature overlap and interfere in the time-frequency domain. When using single-scale fuzzy entropy calculation in the feature extraction stage, the entropy value difference of similar fault types at a specific time scale is masked, reducing the separability of the feature space.
[0021] If the above problems are not solved, the fault feature vectors are likely to form overlapping distribution regions during the clustering process, resulting in fuzzy classification decision boundaries. In actual operation and maintenance, there may be a situation where an arc fault is misjudged as an overload fault, delaying the action time of the protection device. In the long-term operation, insufficient feature extraction will reduce the generalization ability of fault mode recognition, increase the risk of missed reports of abnormal device states, and affect the accuracy of power system reliability assessment.
[0022] When facing the above problems, this application first attempts to use an adaptive signal decomposition method to replace the fixed-parameter decomposition for the difficult problem of non-stationary transient current signal processing. By comparing the frequency band division characteristics of empirical mode decomposition and variational mode decomposition, it is found that variational mode decomposition has the constraint condition of the preset number of modes, which can avoid the mode mixing phenomenon. Then, a dynamic noise recognition mechanism is explored, and permutation entropy is introduced as a signal complexity quantification index to distinguish noise components from effective signals by setting a threshold. In the feature extraction stage, to solve the problem of insufficient representation ability of single-scale entropy, an attempt is made to construct a multi-scale coarse-grained sequence to capture signal characteristics at different time resolutions, and the fuzzy entropy algorithm is combined to enhance the feature robustness. Finally, aiming at the adaptability defect of traditional clustering algorithms to high-dimensional non-linear features, a clustering model based on probability density estimation is studied, and the distance measure calculation method is optimized by introducing the covariance matrix.
[0023] In response to this, this application proposes a distribution box fault detection method, including the following steps: Collect the current signals of the distribution box in different fault states; Perform VMD decomposition on the transient fault current signals in different fault states to obtain IMF components in different frequency bands, calculate the permutation entropy of the IMF components, and perform denoising on them when the permutation entropy is greater than or equal to the preset value. If the permutation entropy is less than the preset value, no denoising is performed; calculate the fuzzy entropy values of each IMF for the denoised and non-denoised IMF components; Use the fuzzy entropy values as fault feature vectors, and cluster the fault feature vectors through the GG clustering algorithm to identify different fault types.
[0024] Among them, VMD decomposition refers to variational mode decomposition, which can specifically decompose non-stationary signals into multiple narrow-band intrinsic mode function components by presetting the number of modes and the penalty factor, and is used to extract fault feature components in different frequency bands to cope with signal non-stationarity. Permutation entropy is an index to measure the complexity of time series, which can specifically be realized by calculating the probability distribution of adjacent permutation patterns of IMF components, and is used to dynamically judge the degree of noise interference for selective denoising. Denoising processing refers to signal denoising of high permutation entropy components, which can specifically be realized by using the wavelet threshold denoising method, and is used to eliminate high-frequency noise interference while retaining effective signal components. Fuzzy entropy value refers to a multi-scale complexity feature, which can specifically be realized by constructing a coarse-grained sequence and calculating the pattern similarity probability, and is used to capture the signal complexity difference at different scales to enhance the feature representation ability. The GG clustering algorithm refers to the generalized Gaussian mixture model clustering, which can specifically be realized by iteratively optimizing the membership matrix and the covariance matrix, and is used to process high-dimensional non-linear feature distributions and optimize the clustering boundary.
[0025] The core innovation of this application lies in achieving signal adaptive noise reduction through VMD decomposition combined with permutation entropy dynamic denoising strategy, constructing a robust feature vector using multi-scale fuzzy entropy, and introducing the GG clustering algorithm to process high-dimensional non-linear feature distributions, forming a complete technical chain from signal preprocessing to feature optimization, effectively solving the problems of insufficient feature extraction and low clustering accuracy in traditional methods.
[0026] The working process and principle of this application are as follows: First, current signals of the distribution box in different fault states are collected, including various working conditions such as normal state, short-circuit fault, and ground fault. The collected current signals usually contain high-frequency noise and non-linear features.
[0027] Next, the variational mode decomposition (VMD) is performed on the collected transient fault current signals. The VMD algorithm decomposes the signal into a preset number of intrinsic mode function (IMF) components through iterative optimization. Each IMF component represents the oscillation mode of the signal in a specific frequency band. VMD decomposition can effectively separate the signal components with different frequency features.
[0028] The permutation entropy of each IMF component is calculated. The permutation entropy reflects the complexity and irregularity of the time series. When the permutation entropy of an IMF component is greater than or equal to the preset threshold, it is considered that this component contains more noise and needs to be denoised. If the permutation entropy is less than the preset threshold, it is considered that this component mainly contains effective signals and no denoising is performed. This adaptive denoising strategy can effectively suppress noise interference while retaining the effective signals.
[0029] The fuzzy entropy value of the IMF components after selective denoising is calculated. By introducing the fuzzy membership function, the fuzzy entropy can better describe the complexity of the signal. Compared with the traditional entropy value, the fuzzy entropy is less sensitive to noise and can extract more stable features.
[0030] The calculated fuzzy entropy value is used as the fault feature vector and input into the Gaussian mixture (GG) clustering algorithm for clustering analysis. The GG clustering algorithm determines the optimal clustering result by estimating the parameters of the Gaussian mixture model. Compared with the traditional K-means algorithm, GG clustering can process data with non-spherical distributions and is suitable for processing high-dimensional non-linear features.
[0031] Through the results of clustering analysis, similar fault features can be grouped into one category, thus realizing the identification and classification of different types of faults. The whole process extracts the effective information in the fault signal to the greatest extent through multi-level signal processing and feature extraction, improving the accuracy of fault detection and classification.
[0032] As a preferred embodiment, the solution of this application is specifically implemented as follows: Collect the current signals of the distribution box under five states: normal operation, single-phase short circuit, two-phase short circuit, three-phase short circuit, and single-phase grounding. The sampling frequency is set to 10 kHz, and the sampling duration is 200 ms.
[0033] Perform VMD decomposition on the collected current signals. The initial number of modes K for VMD decomposition is set to 5. By calculating the signal-to-noise ratio of the reconstructed signal and the original signal, gradually increase the value of K until the signal-to-noise ratio no longer increases significantly, and finally determine the optimal K value.
[0034] Calculate the permutation entropy for each IMF component. The embedding dimension m of the permutation entropy is set to 3, and the time delay τ is set to 1. Set the permutation entropy threshold to 0.6. Perform wavelet threshold denoising on the IMF components with a permutation entropy greater than 0.6, using the soft threshold function.
[0035] Calculate the multi-scale fuzzy entropy for the processed IMF components. Set the range of the scale factor τ to 1 - 20, the similarity tolerance r for fuzzy entropy calculation to 0.15 times the standard deviation, and the embedding dimension m to 2. Select the fuzzy entropy values of the first 5 scales with the largest variance as the feature vector.
[0036] Input the extracted feature vector into the GG clustering algorithm. Set the number of cluster centers to 4, corresponding to 5 fault types. Iteratively optimize the membership matrix and the cluster centers until the objective function converges. Finally, obtain the membership degrees of each sample to different fault types to achieve fault classification.
[0037] Through the above solution, this application can effectively solve the problems of insufficient signal processing and inadequate feature extraction in traditional distribution box fault detection. The combination of VMD decomposition and the adaptive denoising strategy can better separate the effective signal and noise, improving the effectiveness of signal processing. The multi-scale fuzzy entropy feature can capture the complexity features of the signal from multiple time scales, enhancing the robustness of the features. The GG clustering algorithm is suitable for processing high-dimensional non-linear features, improving the accuracy of clustering. The overall solution realizes the accurate detection and classification of distribution box faults, providing strong support for the safe operation of the power system.
[0038] In some of the above solutions of this application, it is difficult for traditional methods to adaptively select the optimal value when determining the number of IMF components K, resulting in the decomposition result may contain redundant modes or lose effective modes, thereby affecting the accuracy of subsequent permutation entropy calculation and denoising processing, and finally reducing the reliability of fault feature extraction and the clustering recognition effect.
[0039] In response to this, the present application further proposes that when determining the number K of IMF components, initialize the value of K, calculate the Euclidean distance between each IMF component and the probability density function of the original signal, find the boundary between the two IMFs with the largest Euclidean distance increment, select several components with a smaller Euclidean distance as effective mode classifications and perform reconstruction, then solve the signal-to-noise ratio between the original signal and the reconstructed signal, perform a +1 operation on the value of K, repeat the above steps, and select the K value of the VMD decomposition with the highest signal-to-noise ratio of the reconstructed signal as the optimal K value.
[0040] Among them, the initialization of the value of K usually starts from a small integer value, such as K = 2 or K = 3, to reduce the computational complexity. The probability density function of each IMF component is generated by the kernel density estimation method, and the probability density function of the original signal is calculated based on its actual sampling data distribution. The calculation of the Euclidean distance uses the difference measure between discrete probability distributions, and the specific formula is ∑(p i -q i ) 2 , where p i and q i respectively represent the probability values of the IMF component and the original signal in the same interval. The boundary point with the largest Euclidean distance increment is determined by comparing the distance differences between adjacent IMF components. For example, when the distance difference between the m-th and the (m + 1)-th components exceeds a preset threshold, the first m components are classified as effective modes. The reconstructed signal is realized by weighted superposition of effective mode components, and the weight coefficients can be dynamically adjusted according to the energy proportion of each component. The calculation of the signal-to-noise ratio uses a logarithmic form, such as 10·log10(Ps / Pn), where Ps is the power of the original signal and Pn is the residual power of the reconstructed signal and the original signal. During the iteration process, the upper limit of the value of K can be set to an empirical value, such as K max = 10, to avoid infinite loops.
[0041] Specifically, after initializing the value of K, the effective modes are screened through the Euclidean distance of the probability density function, which can distinguish the signal dominant components from the noise components. The components with smaller Euclidean distance are selected for reconstruction, retaining the modes that are closest to the statistical characteristics of the original signal and avoiding mode aliasing caused by subjectively setting the value of K. By gradually increasing the value of K and calculating the signal-to-noise ratio, the decomposition process achieves a balance between retaining effective information and suppressing noise. When the signal-to-noise ratio reaches the peak, the iteration is terminated. At this time, the corresponding value of K not only avoids introducing false components due to over-decomposition but also prevents losing key fault features due to under-decomposition. This dynamic optimization process synergizes with the subsequent permutation entropy threshold screening and fuzzy entropy feature extraction to ensure that the denoised IMF components have higher feature discrimination, thereby improving the recognition accuracy of the clustering algorithm for fault types. For example, when K = 5, the signal-to-noise ratio reaches the maximum value. Among the 5 IMF components obtained by decomposition at this time, the first 3 are determined to be effective modes, and their permutation entropy values all exceed the preset threshold. The multi-scale fuzzy entropy features calculated after wavelet threshold denoising show better inter-class separation in GG clustering.
[0042] As a preferred embodiment, the solution of the present application is specifically implemented as follows: When determining the number K of IMF components, first initialize the value of K. For example, set the initial value of K to 2. Then calculate the Euclidean distance between each IMF component and the probability density function of the original signal. Specifically, the kernel density estimation method can be used to calculate the probability density function, and the discrete integral method can be used to calculate the Euclidean distance. Next, find the two IMF components with the largest Euclidean distance increment as the demarcation points. For example, for the 5 IMF components obtained by a certain decomposition, the calculated Euclidean distances are 0.1, 0.3, 0.8, 1.2, and 1.5 respectively. Then select the interval between 0.8 and 1.2 as the demarcation point. Subsequently, select several components with smaller Euclidean distance (such as the first 3) as effective modes for classification and reconstruction. The reconstruction method can adopt simple summation or weighted average, etc. Further, calculate the signal-to-noise ratio between the original signal and the reconstructed signal. The peak signal-to-noise ratio (PSNR) can be used as an evaluation index. Perform an operation of adding 1 to the value of K and repeat the above steps. Finally, select the value of K for VMD decomposition when the signal-to-noise ratio of the reconstructed signal is the highest as the optimal value of K. For example, after multiple iterations, it is found that the signal-to-noise ratio is the highest when K = 4, then select 4 as the final number of IMF components.
[0043] Through the above technical solutions, the present application realizes the adaptive optimization of the K value in VMD decomposition. Thereby, the problems of modal redundancy or information loss caused by the traditional fixed K value method are avoided, and the decomposition quality of IMF components is improved. Specifically, by calculating the Euclidean distance and setting the demarcation point, the effective modes and noise modes can be effectively distinguished, and the deviation caused by the subjective setting of the K value can be reduced. Further, using the signal-to-noise ratio as an evaluation index ensures the quality of the reconstructed signal, providing a reliable basis for subsequent permutation entropy calculation and fuzzy entropy feature extraction. This adaptive optimization method not only improves the accuracy of fault feature extraction but also enhances the effect of clustering recognition, thus improving the overall performance and reliability of the distribution box fault detection.
[0044] In some of the above solutions of the present application, it is proposed to screen IMF components through permutation entropy for denoising. However, in the process of selecting IMF components for denoising after determining the K value, if conventional denoising methods are used, it may lead to the loss of effective signals or the residue of noise. Especially for non-stationary transient fault current signals, traditional denoising methods cannot balance the problems of high-frequency noise suppression and low-frequency feature retention.
[0045] In response to this, the present application further proposes that after determining the K value, select the IMF components under the current K value, and select the IMF whose permutation entropy is greater than or equal to the preset value for denoising, and its denoising method is wavelet threshold denoising.
[0046] Among them, the screening of IMF components is based on the comparison of the permutation entropy value with the preset threshold, and the preset value can be set to any value in the range of 0.5 - 0.8, such as 0.65. In the wavelet threshold denoising process, the wavelet basis function can be selected as db4 or sym8, the decomposition layer is set to 3 - 5 layers, and the threshold rule adopts the improved Sqtwolog threshold strategy. The permutation entropy calculation of IMF components analyzes the signal complexity through a sliding window, and the window length can be configured to be 1 / 4 to 1 / 2 of the signal period, such as 128 sampling points. The screened IMF components are subjected to wavelet soft threshold processing to achieve noise suppression, where the high-frequency noise components are attenuated, and the low-frequency effective components are retained through the continuity of the threshold function. The combined application of this screening mechanism and denoising method enables the high-frequency noise components to be processed directionally, while the low-complexity components remain in their original state, avoiding signal distortion caused by over-denoising.
[0047] Specifically, after completing the VMD decomposition and determining the optimal K value, the permutation entropy of each IMF component is calculated first. When the permutation entropy value of a certain component is detected to exceed the preset threshold, it indicates that the component contains significant noise components, and at this time, wavelet threshold denoising processing is triggered. During the wavelet decomposition process, the high-frequency detail coefficients are shrunk through an adaptive threshold, while the low-frequency approximation coefficients are completely retained. The denoised IMF components and the unprocessed components jointly participate in subsequent feature extraction, where the noise interference of high-complexity components is effectively suppressed, and the original features of low-complexity components are completely retained. This sorting and processing mechanism dynamically distinguishes noise-dominated components from signal-dominated components, maintaining the integrity of fault features while ensuring the denoising effect, and is particularly suitable for the separation requirements of mutation features and steady-state noise in transient current signals.
[0048] As a preferred embodiment, the solution of the present application is specifically implemented as follows: After determining the optimal K value of the VMD decomposition, the permutation entropy of the IMF components at the current K value is calculated. Set the permutation entropy threshold to 0.6. When the permutation entropy of the IMF component is greater than or equal to 0.6, wavelet threshold denoising processing is performed on this component. The specific steps of wavelet threshold denoising include: first, select the db4 wavelet basis function and perform 3-layer wavelet decomposition on the IMF component; then use the soft threshold function to process the wavelet coefficients, and the threshold selection adopts the VisuShrink method; finally, reconstruct the processed wavelet coefficients to obtain the denoised IMF component. For IMF components with a permutation entropy less than 0.6, they are kept in their original state without denoising.
[0049] Through the above technical solutions, the present application realizes effective denoising of non-stationary transient fault current signals. By screening the IMF components that need to be denoised through the permutation entropy threshold, over-processing of low-noise components is avoided. Using the wavelet threshold denoising method can adaptively suppress high-frequency noise while retaining the low-frequency effective components of the signal. This combined strategy solves the mode mixing problem existing in traditional denoising methods when dealing with non-stationary signals, and is particularly suitable for the situation where high-frequency noise and low-frequency fault features are mixed in transient fault current signals. Thus, it not only ensures the effectiveness of noise removal but also avoids the distortion of effective signals, improving the accuracy of subsequent fault feature extraction and classification.
[0050] In some of the above solutions of the present application, if only single-scale analysis is used to calculate the fuzzy entropy of the IMF components, the dynamic characteristics of the fault signal at different time scales cannot be effectively captured, resulting in limited characterization ability of the entropy features and affecting the discrimination of fault types by subsequent clustering algorithms.
[0051] In response to this, the present application further proposes a technical solution for constructing a multi-scale coarse-grained sequence of the IMF component sequence and calculating the fuzzy entropy.
[0052] Among them, the construction of the multi-scale coarse-grained sequence calculates the segment mean of the original signal through the scale factor τ, and the value range of τ covers multiple levels from the original resolution to the macroscopic trend analysis. For example, the value of τ can be an integer from 1 to 5, and the specific value is adjusted according to the signal length N. When N is 1000, the maximum value n of τ can be set to 20. The generation of the coarse-grained sequence is achieved by dividing the original sequence into sub-segments of length N / τ and calculating the mean of each segment. For example, when τ = 2, the sequence is divided into N / 2 segments, and the mean of two data points is included in each segment. The fuzzy entropy of the coarse-grained sequences at different scales is calculated independently to form a multi-dimensional feature vector. For example, when n = 5, each IMF component will generate 5 fuzzy entropy values at different scales.
[0053] Specifically, before calculating the fuzzy entropy, the IMF component needs to be processed by multi-scale coarse-graining. The original sequence X is divided into N / τ sub-segments, and the arithmetic mean of the data points within each sub-segment constitutes the coarse-grained sequence ; For example, when τ = 3, the j th sub-segment contains x {3j - 2}, x {3j - 1} and x {3j} three data points, and its mean is . By continuously changing the value of τ, multiple coarse-grained sequences are generated. For example, τ = 1 corresponds to the original sequence, τ = 2 corresponds to the average sequence of every two data points, and τ = 3 corresponds to the average sequence of every three data points. The fuzzy entropy of each coarse-grained sequence is calculated using the same parameter settings. For example, the width r of the fuzzy function can be set to 0.15 times the standard deviation of the original sequence, and the embedding dimension m is set to 2. By combining the fuzzy entropy values at different scales into a multi-dimensional feature vector, such as including five entropy values with τ = 1 to 5, the feature vector can simultaneously reflect the differential characteristics of the signal in short-term fluctuations and long-term trends. Thus, when the GG clustering algorithm processes high-dimensional features, it can enhance the ability to distinguish fault types through the distribution differences of entropy values at different scales.
[0054] As a preferred embodiment, the solution of the present application is specifically implemented as follows: When calculating the fuzzy entropy for each IMF component, first construct a multi-scale coarse-grained sequence ; is the sequence length, and its formula is as follows: In the above formula , represents the scale factor. For a given the original sequence is divided into coarse-grained vectors of length ; subsequently, for each scale of the coarse-grained sequence calculate the fuzzy entropy.
[0055] Specifically, when τ = 1, is equivalent to the original sequence X; when τ = 2, it is obtained by taking the average of every two adjacent points of the original sequence; when τ = 3, it is obtained by taking the average of every three adjacent points of the original sequence, and so on.
[0056] For example, for the original sequence X = {1, 2, 3, 4, 5, 6, 7, 8}, when τ = 2, the obtained coarse-grained sequence = {1.5, 3.5, 5.5, 7.5}; when τ = 3, the obtained coarse-grained sequence = {2, 5, 8}.
[0057] Furthermore, for the coarse-grained sequence at each scale τ calculate the fuzzy entropy. The fuzzy entropy calculation process includes: setting the embedding dimension m and the similarity tolerance r, constructing m-dimensional vectors, calculating the distances between vectors, applying the fuzzy membership function, and finally calculating the fuzzy entropy value.
[0058] Thus, for each IMF component, 10 fuzzy entropy values at different scales can be obtained, forming a multi-dimensional feature vector. These feature vectors will be used as the input for the subsequent GG clustering algorithm to identify different fault types.
[0059] Through the above technical solutions, the present application realizes the multi-scale analysis of IMF components, overcomes the problem that the single-scale fuzzy entropy cannot effectively capture the dynamic characteristics of fault signals at different time scales. The multi-scale coarse-graining process enables the feature vector to contain the full-scale information from micro fluctuations to macro morphology, enhancing the classification ability for complex fault types. At the same time, by calculating the fuzzy entropy at different scales, the robustness of the features is improved, and the influence of noise on feature extraction is reduced. This multi-scale analysis method provides richer and more reliable input data for the subsequent clustering algorithm, thereby improving the accuracy and reliability of fault detection.
[0060] In some of the above solutions of the present application, there are problems of redundant feature dimensions and noise interference in the generation method of the multi-scale fuzzy entropy as a fault feature vector. The difference in the characterization ability of the fuzzy entropy values at different scales for fault patterns leads to a decrease in the clustering recognition accuracy.
[0061] In response to this, the present application further proposes a calculation method for multi-scale fuzzy entropy. Its mean represents the overall entropy value distribution level through the arithmetic mean formula, and the variance quantifies the sensitivity of the fuzzy entropy at each scale through the dispersion formula. After sorting the variances, the fuzzy entropy of the first Z scales is selected as the final feature input.
[0062] Among them, the mean value is calculated by arithmetic mean. For example, when the scale factor τ takes values from 1 to 5, the fuzzy entropy values corresponding to each scale are accumulated and then divided by the total number of scales, which is 5. The variance is calculated based on the mean result. For example, when the fuzzy entropy value of a certain scale τ = 3 significantly deviates from the mean, its variance contribution degree will be higher than that of other scales. After sorting the variances, the selection of the first Z scales can be achieved by setting a fixed threshold or a dynamic ratio. For example, the value range of Z is from 3 to 5, or 30% of the total sample size is selected according to the front. The screened feature dimensions cooperate with the VMD decomposition and permutation entropy denoising processing in the previous steps, eliminate low-discrimination noise through dimensionality reduction, and at the same time retain the key entropy value features of the denoised IMF components.
[0063] Specifically, when calculating the multi-scale fuzzy entropy, first calculate the entropy value for each coarse-grained sequence of each scale τ to generate an initial feature set. Subsequently, the baseline of the entropy value distribution is determined through mean calculation, and variance calculation is used to identify the scales with significant entropy value fluctuations. For example, when the fuzzy entropy value of the fault current signal under a certain scale shows a large difference between the normal and abnormal states, its variance value will be significantly higher than that of other scales. The entropy values corresponding to the selected high-variance scales are input into the GG clustering algorithm. For example, select the fuzzy entropy values of the first 3 scales τ = 1, τ = 4, τ = 5 in terms of variance ranking to form a feature vector. This process reduces the feature dimensions through a statistical screening mechanism, enabling the GG clustering to reduce the interference of redundant data when calculating the distance measure, and at the same time retain the key entropy value information sensitive to the fault type, thereby improving the convergence speed of the clustering center and the classification accuracy.
[0064] As a preferred embodiment, the solution of the present application is specifically implemented as follows: First, calculate the multi-scale fuzzy entropy , then calculate the mean of these fuzzy entropy values , k = 1, 2, … n. For example, n = 20 scales can be selected, and then the variance is calculated according to the fuzzy entropy: , and the 20 calculated variance values are sorted from largest to smallest.
[0065] Select the fuzzy entropy corresponding to the first Z scales after sorting as the final feature. For example, Z = 10 can be selected, that is, select the fuzzy entropy values of the 10 scales with the largest variance.
[0066] Input these 10 selected fuzzy entropy values as feature vectors into the GG clustering algorithm for fault type identification.
[0067] Through the above technical solutions, the present application can effectively screen out the feature dimensions that are highly sensitive to the fault state, reducing the interference of redundant and noise information on the clustering results. Thereby, the recognition accuracy and efficiency of the GG clustering algorithm for the fault types of distribution boxes are improved, making the fault detection results more accurate and reliable. Further, by reducing the feature dimensions, the computational complexity is reduced, and the real-time performance of the algorithm is improved.
[0068] In some of the above solutions of the present application, traditional clustering algorithms assume that the feature data is spherically distributed and use a fixed distance measure, resulting in poor adaptability to high-dimensional non-linear feature data, the clustering center update process is prone to falling into local optimality, and the problem of covariance differences between different classes cannot be effectively handled.
[0069] In response to this, the present application further proposes including setting a termination tolerance ε > 0, randomly initializing the membership matrix as U, and then calculating the clustering center, and its formula is: , where l is an integer and l > 1 in the above formula; calculating the maximum likelihood estimation distance measure, and the calculation formula is: , in the above formula is the covariance matrix of the i-th cluster, is the prior probability that the i-th cluster is selected; updating the membership matrix U, which is: ; when is satisfied, the iteration is terminated. If the condition is not satisfied, that is, let l = l + 1, and continue to iterate V, U until is satisfied, so that the function J obtains the minimum value.
[0070] Among them, the value of the termination tolerance ε can be on the order of 0.01 or 0.001, which is used to control the iteration accuracy. The initialization of the membership matrix uses uniformly distributed random numbers to generate, for example, the initial membership degree is assigned in the interval [0, 1]. The value range of the weighted exponent M is usually from 1.5 to 3.0, and 2.0 can be taken in specific implementations. The covariance matrix is calculated through the sample covariance matrix, for example, updated using the maximum likelihood estimation method. The calculation method of the prior probability can be the proportion of the number of samples of each category to the total number of samples. For example, when the proportion of a certain category of samples is 30%, its takes 0.3.
[0071] Specifically, a convergence criterion is established by setting a termination tolerance ε > 0. The calculation stops when the change in the membership matrix between two adjacent iterations is less than ε, avoiding ineffective iterations. Randomly initializing the membership matrix breaks the initial parameter constraints. For example, the matrix elements are initialized with pseudo-random numbers generated by a computer, reducing the risk of falling into local optima. During the calculation of the cluster centers, the power operation of the weighted exponent M strengthens the weight of samples with high membership degrees. For example, when the membership degree of a sample to a certain class reaches 0.9, the result of its M -th power operation will be significantly higher than that of samples with low membership degrees. The maximum likelihood estimation distance measure quantifies the distribution difference through the inverse matrix operation of the covariance matrix A_i. For example, for a sample cluster with an elliptical distribution, this measure can accurately reflect the Mahalanobis distance from the sample to the cluster center. The membership degree update formula dynamically adjusts the sample belonging probability by normalizing the ratio of distance measures. For example, when the distance of a sample to the current class is 1 / 2 of the distance to other classes, its membership degree will be increased to more than 0.5. During the iteration process, the cluster centers, covariance matrices, and membership degrees are updated synchronously. For example, in each iteration, the new cluster centers are calculated first, then the covariance matrices are updated, and finally the membership matrix is corrected, forming a closed-loop optimization process. This technical solution effectively processes high-dimensional non-linear feature data by dynamically adjusting the distance measure and probability weight. For example, it can still accurately classify fault categories in a 50-dimensional feature space, improving the clustering accuracy by more than 15% compared with traditional algorithms.
[0072] Through the above technical solution, this application improves the iteration mechanism of the GG clustering algorithm and solves the problem of insufficient adaptability of traditional clustering methods to high-dimensional non-linear features. Setting a clear termination tolerance establishes a convergence criterion, avoiding ineffective iterations. Randomly initializing the membership matrix breaks the strong constraints of the initial parameters on the results, reducing the risk of falling into local optima. When calculating the cluster centers, the power operation of the weighted exponent is introduced to strengthen the influence weight of the membership degree on the cluster centers, making the center vector closer to the real data distribution. The maximum likelihood estimation distance measure quantifies the distribution differences of samples in different categories through the inverse matrix operation of the covariance matrix, breaking through the spherical distribution hypothesis limitation. The membership matrix update formula dynamically adjusts the sample belonging probability by normalizing the ratio of distance measures for different categories, improving the partitioning accuracy of complex feature spaces. The iteration termination condition is based on the comparison of the norms of the changes in the membership matrix, ensuring that the algorithm stops in a timely manner when reaching a stable state, taking into account both computational efficiency and result reliability.
[0073] In some of the above solutions of this application, traditional clustering algorithms have problems such as poor adaptability to non-linear distributions, sensitivity to noise, and low convergence efficiency in processing high-dimensional fault features.
[0074] In response to this, this application further proposes a technical solution to optimize the GG clustering process by dynamically adjusting the covariance matrix and prior probability.
[0075] Among them, the construction of the dynamic covariance matrix uses the sample and cluster center covariance data generated during the iterative process. Its matrix elements are obtained through membership-weighted calculation. When specifically implemented, the covariance update period can be set to automatically adjust after each iteration. The calculation of the prior probability is based on the statistical frequency of the attribution of samples of each category in the historical iterative data. For example, a sliding window can be set to statistically calculate the mean membership degree of the last five iterations as the current probability value. The setting range of the termination tolerance is recommended to be between 0.001 and 0.01. When specifically implemented, an exponential decay strategy can be selected to dynamically adjust the threshold according to the sample size. The initialization of the membership matrix uses a uniform distribution random number generator to ensure that the initial values are uniformly distributed within the interval [0, 1]. The value of the weighted exponent M is preferably 2, and it can be extended to the interval of 1.5 - 3.0 for adjustment in the case of special sample distributions. The calculation of the maximum likelihood distance measure integrates multi-dimensional statistical characteristics, and the Cholesky decomposition method can be used for the covariance inverse matrix operation in its exponential term to improve the calculation efficiency.
[0076] Specifically, during the execution of the GG clustering algorithm, the iterative process is first started through a randomly generated initial membership matrix. In each iteration, the weighted average method is used to calculate the cluster center, where the M-th power of the membership degree is used as the weight factor to strengthen the influence of samples with high confidence on the center position. The update of the dynamic covariance matrix is based on the current membership distribution, and the weighted covariance calculation is used to make the shape of each cluster adapt to the sample distribution characteristics. The construction of the maximum likelihood distance measure expands the Euclidean distance to the Mahalanobis distance form through the determinant and inverse matrix operations of the covariance matrix, effectively capturing the non-linear correlation between high-dimensional features. The calculation of the relative distance ratio in the membership update formula adjusts the sensitivity of sample attribution through the exponential parameter, making the membership degree allocation of noise samples more reasonable. The iteration termination condition is monitored by the difference in the Frobenius norms of the membership matrices for two consecutive times. When the change amount is lower than the preset threshold, the calculation process is automatically terminated. This mechanism significantly reduces redundant calculations while maintaining the clustering accuracy. The entire optimization process synergizes with the multi-scale fuzzy entropy feature extraction in the prior art. The dynamic covariance matrix can effectively match the spatial distribution characteristics of different scale features, and the prior probability mechanism balances the weight differences between multi-scale features, jointly improving the recognition accuracy of complex fault patterns.
[0077] Through the above technical solutions, this application introduces a dynamically adjusted covariance matrix and prior probability, optimizing the GG clustering process. The maximum likelihood estimation distance measure takes into account the non-linear distribution of high-dimensional features, improving the accuracy of cluster center update. The dynamic adjustment mechanism of the covariance matrix enhances the robustness of the algorithm to noise, making the clustering results more accurately reflect the true distribution of fault characteristics. The relative distance ratio calculation is used for the update of the membership matrix, improving the convergence efficiency. Overall, this solution improves the clustering effect of high-dimensional fault features and enhances the accuracy and efficiency of distribution box fault recognition.
[0078] In some of the above solutions of this application, a method is proposed to cluster the fault feature vectors through the GG clustering algorithm to identify different fault types. However, traditional electronic devices have problems with insufficient real-time performance when executing such complex clustering algorithms and cannot efficiently process high-dimensional non-linear feature data, resulting in slow fault detection response speed and affecting the safety of the power grid.
[0079] In response to this, this application further proposes an electronic device, including a memory and a processor. A computer program is stored in the memory, and the processor is configured to run the computer program to execute the distribution box fault detection method.
[0080] Among them, the memory is used to solidify the computer program of the complete detection process including VMD decomposition, permutation entropy screening, multi-scale fuzzy entropy calculation and GG clustering algorithm, avoiding resource consumption caused by repeated programming. The processor directly calls the pre-stored algorithm logic by executing the solidified program in a specialized manner, eliminating the calculation delay generated when a general-purpose processor dynamically parses complex algorithms. During the execution of the GG clustering algorithm, the processor adopts a parallel computing architecture to accelerate matrix operations for the high-dimensional operations of iteratively updating the membership matrix, covariance matrix and cluster center. For example, different data blocks in different dimensions are processed simultaneously by a multi-core processor. The memory and the processor are connected by a high-speed bus to ensure that the data throughput meets the real-time processing requirements. For example, a DDR4 memory interface is used to achieve a transmission rate of more than 20 GB per second.
[0081] Specifically, when the processor runs the solidified program, it first reads the pre-configured fault detection algorithm instruction set from the memory, including VMD decomposition parameters, permutation entropy thresholds and multi-scale fuzzy entropy calculation rules. During the GG clustering process, the processor initializes the data according to the membership matrix pre-stored in the memory and directly executes the iterative update of the covariance matrix, avoiding the delay caused by dynamic memory allocation. For example, when processing a 1000-dimensional fault feature vector, the processor completes an update of the cluster center within 5 milliseconds through the matrix operation unit. The solidified program stored in the memory further optimizes the data access path, stores the high-dimensional feature vectors aligned with the cache lines, and reduces the waiting cycle for the processor to access the memory. Through the deep adaptation of hardware and algorithms, when the electronic device executes the GG clustering algorithm, it can shorten the clustering process that takes 200 milliseconds in traditional devices to within 50 milliseconds, while maintaining a clustering accuracy of more than 98%, meeting the fast response requirements of the power system for fault detection.
[0082] As a preferred embodiment, the solution of the present application is specifically implemented as follows: the electronic device is configured as a dual-core ARMCortex-A72 architecture processor with a main frequency set to 1.8GHz, equipped with an LPDDR4 memory module as a memory, and the storage capacity is set to 8GB. The computer program solidified in the memory contains a pre-compiled machine instruction set, which is optimized to directly call the hardware acceleration unit to perform the VMD decomposition operation, wherein the decomposition layer adaptive module realizes dynamic adjustment of the K value by register preloading. When the processor executes the GG clustering algorithm, it uses the built-in NEON coprocessor to parallelly calculate the membership matrix update operation, and specifically uses block matrix multiplication instructions to accelerate the operation when calculating the covariance matrix. During the program running, the multi-scale fuzzy entropy feature vector is directly transferred to the processor's cache area through the DMA controller, avoiding the delay caused by traditional memory copying.
[0083] Through the above technical solution, this application effectively eliminates the instruction decoding overhead of general-purpose processors when dynamically parsing algorithms, and realizes real-time clustering calculations of high-dimensional feature vectors by cooperating with coprocessors through pre-compiled instruction sets. The hardware acceleration unit parallelizes the iterative process of the membership matrix, reducing the computational time of covariance matrix updates in the GG clustering algorithm to 1 / 5 of the traditional serial operation, while ensuring that the cluster center convergence accuracy error is less than 0.3%. In the actual operation environment of the power grid, this electronic device can complete the feature identification of three-phase short-circuit faults within 12 milliseconds, meeting the millisecond-level response requirements of the power system to transient faults.
[0084] In some of the above-mentioned solutions of this application, when the distribution box fault detection method based on VMD decomposition, fuzzy entropy and GG clustering algorithm is run on a general computing device, there is a problem of insufficient real-time performance of the algorithm due to unreasonable hardware resource allocation.
[0085] In this regard, the present application further proposes an electronic device, including a memory and a processor, wherein a computer program is stored in the memory, and the processor is configured to run the computer program to execute a distribution box fault detection method.
[0086] The memory uses an embedded flash memory chip to implement program storage, with a capacity configuration ranging from 512MB to 2GB, supporting parallel data access channels. The processor uses a multi-core digital signal processor with a main frequency set to 800MHz to 1.5GHz and a built-in dedicated floating-point unit. The memory and processor are connected through a 64-bit bus, and the memory bandwidth is optimized to 12.8GB / s. The program storage method includes an instruction prefetch mechanism to store the VMD decomposition core algorithm code segment in the cache area. The hardware resource allocation strategy includes a dynamic priority scheduling module, which allocates more than 70% of computing resources to GG clustering calculations. The instruction set optimization includes SIMD vectorization instructions, which can complete the parallel calculation of 4 fuzzy entropy values in a single cycle.
[0087] Specifically, the program firmware storage eliminates the millisecond-level delay caused by the dynamic loading of programs in traditional general-purpose devices. Through the instruction prefetch mechanism, the startup time of the VMD decomposition algorithm is shortened to the microsecond level. The multi-core processor, combined with a dedicated floating-point unit, increases the calculation speed of the permutation entropy of the IMF components by more than three times. The 64-bit bus and optimized memory bandwidth ensure the high-speed transmission of the fault feature vector during the clustering process, avoiding data congestion. The dynamic priority scheduling module monitors the computing load in real time, automatically allocating 80% of the processor resources to the VMD decomposition during the transient current signal processing stage and switching 60% of the resources to the GG algorithm during the clustering stage. The SIMD instruction set enables four-channel parallel computing, reducing the time-consuming of multi-scale fuzzy entropy feature extraction to one-fourth of the traditional method. The deep adaptation of the hardware architecture and the algorithm process controls the complete fault detection cycle within 50 ms, meeting the real-time requirements of power system online monitoring.
[0088] As a preferred embodiment, the solution of the present application is specifically implemented as follows: The electronic device adopts a dual-channel DDR4 memory and a quad-core ARM Cortex-A55 processor architecture. The memory is configured to store the machine code program generated by cross-compilation. The program includes a VMD decomposition module, a multi-scale fuzzy entropy calculation module, and a GG clustering operation module. The processor allocates a dedicated computing core to the transient current signal processing task through the hardware interrupt priority mechanism. Among them, the VMD decomposition operation is mapped to the physical core equipped with the NEON instruction set, and the clustering calculation task is allocated to the physical core equipped with the VFPv4 floating-point unit. The DMA transfer is realized between the memory and the processor through the AXI bus protocol. The program instruction set is solidified in the NOR Flash partition of the memory after being compiled and optimized.
[0089] Through the above technical solutions, the present application realizes the real-time deployment of the distribution box fault detection algorithm on the embedded hardware platform, eliminating the operation delay caused by dynamic memory allocation and process scheduling in general computing devices. The architecture-level collaborative design of the memory and the processor enables the computing pipelines of signal decomposition, feature extraction, and pattern classification to be executed in parallel at the hardware level, effectively solving the resource competition problem existing in the traditional method when processing high-dimensional data, and ensuring that the fault detection process is completed within a 20 ms time window, meeting the strict time limit requirements of power system online monitoring.
[0090] In some of the above solutions of the present application, the collaborative mechanism between the traditional storage medium and the processor has problems such as low program call efficiency and insufficient real-time performance, resulting in the inability to quickly complete the clustering calculation when processing high-dimensional non-linear features, affecting the timeliness of fault detection.
[0091] In response to this, the present application further proposes a readable storage medium, on which a program is stored. When the program is executed by a processor, it implements the distribution box fault detection method.
[0092] Among them, the readable storage medium can be selected from a solid-state drive, a flash chip or an embedded memory, with a data reading speed not lower than 500 MB / s and supporting multi-threaded concurrent access. When the program is executed by the processor, the processor can be configured with a multi-core architecture, and each core independently processes fuzzy entropy calculation tasks of different scales. The storage medium and the processor are connected through a PCIe bus, and the transmission delay is controlled within 10 μs. After the program code is compiled and optimized, it forms an instruction sequence, including a parallel computing instruction set, such as SIMD instructions, for accelerating the iterative operation of the covariance matrix in the GG clustering algorithm. During the program execution, the update of the membership matrix and the calculation of the clustering center adopt pipelining processing to avoid resource idleness caused by data waiting.
[0093] Specifically, when the processor calls the program in the storage medium, the current signal acquisition module caches the data into the memory mapping area, and the processor directly reads the signal data through the DMA method. The program instructions control the processor to perform multi-scale fuzzy entropy calculation on the IMF components, where the construction of the coarse-grained sequence and the distribution of the entropy value calculation tasks are executed synchronously by different arithmetic units. In the GG clustering stage, the inverse operation of the covariance matrix is realized through the LU decomposition algorithm, and the decomposition process is parallel accelerated by the floating-point arithmetic unit of the processor. When updating the membership matrix, an optimized strategy combining the look-up table method and Taylor expansion is adopted for the exponential operation, shortening the single iteration time to within 5 ms. After the program execution is completed, the clustering result triggers the output of the fault type through the interrupt mechanism, and the end-to-end delay of the entire processing flow does not exceed 50 ms. Thus, the real-time processing of high-dimensional features and clustering calculations is realized, ensuring that the timeliness of fault detection is increased by more than 40%, and at the same time supporting the seamless migration of the algorithm on different hardware platforms.
[0094] As a preferred embodiment, the solution of the present application is specifically implemented as follows: The readable storage medium uses a solid-state drive as the carrier, and the distribution box fault detection program stored thereon is configured to include a GG clustering algorithm module and a multi-scale fuzzy entropy feature processing module. After the program is loaded by the processor, the current signal acquisition module obtains real-time monitoring data through a high-speed ADC interface, and the data is transmitted to the signal decomposition thread for VMD operation. The decomposed IMF components synchronously execute permutation entropy screening and wavelet threshold denoising through a parallel computing unit. After the multi-scale fuzzy entropy feature vector is generated, the adaptive memory allocation mechanism maps the feature data to the GPU accelerator, and the fault mode classification is completed through the covariance matrix iteration module of the GG clustering algorithm, and the classification result is output to the warning system through the DMA channel. During the program execution, a double-buffer structure is adopted to realize the pipelining operation of data preprocessing and clustering calculation.
[0095] Through the above technical solution, the present application realizes the hardware encapsulation of the distribution box fault detection process, eliminates the data transfer delay between the traditional storage medium and the processor, and integrates the feature extraction, denoising and clustering algorithms into continuously executed machine code through program solidification and instruction set optimization, so that the number of clustering iterations during high-dimensional nonlinear feature processing is reduced by more than 40%. The standardized interface design of the storage medium enables the detection program to be deployed across platforms to different computing power devices, achieving millisecond-level response in both ARM architecture embedded systems and X86 architecture industrial computers, solving the real-time fluctuation problem caused by dynamic program loading in traditional solutions. The covariance matrix calculation module shortens the cluster center update cycle to a single clock cycle through instruction-level parallel optimization, effectively avoiding resource competition during high-dimensional feature space operations.
[0096] The above description is only an embodiment of the present application and is not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.
[0097] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different terms to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of the components as the criteria for distinction. For example, "including" mentioned throughout the specification and claims is an open term and should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve technical problems within a certain error range and basically achieve technical effects.
[0098] It should be noted that the terms "include," "comprises," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such product or system. In the absence of further limitations, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the product or system comprising the element.
[0099] The foregoing description has shown and described several preferred embodiments of the present invention. However, as mentioned above, it should be understood that the present invention is not limited to the forms disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be changed within the scope of the inventive concept herein through the above teachings or the techniques or knowledge in the relevant field. Any changes and variations made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention.
Claims
1. A method for detecting faults in a distribution box, characterized in that, The steps are as follows: S100. Collect the current signals of the distribution box under different fault states; S200. Perform VMD decomposition on the transient fault current signals under different fault states to obtain the IMF components in different frequency bands, calculate the permutation entropy of the IMF components. When the permutation entropy is greater than or equal to the preset value, denoise it. If the permutation entropy is less than the preset value, no denoising is performed; calculate the fuzzy entropy values of each IMF for the denoised and non-denoised IMF components; S300. Use the fuzzy entropy values as the fault feature vectors, and perform clustering on the fault feature vectors through the GG clustering algorithm to identify different fault types.
2. The method for detecting faults in a distribution box according to claim 1, characterized in that, When determining the number K of IMF components, initialize the K value, calculate the Euclidean distance between each IMF component and the probability density function of the original signal, find the two IMFs with the largest increment of Euclidean distance as the boundary, select several components with smaller Euclidean distance as the effective mode classification and perform reconstruction, then solve the signal-to-noise ratio between the original signal and the reconstructed signal, perform a +1 operation on the K value and repeat the above steps, and select the K value of VMD decomposition with the highest signal-to-noise ratio of the reconstructed signal as the optimal K value.
3. A method for detecting faults in a distribution box according to claim 2, characterized in that, After determining the K value, select the IMF components under the current K value, and denoise the IMF when its permutation entropy is greater than or equal to the preset value. The denoising method is wavelet threshold denoising.
4. A power distribution box fault detection method according to claim 1, characterized in that When calculating the fuzzy entropy for each IMF component, for the IMF component sequence construct a multi-scale coarse-grained sequence , where is the sequence length, and its formula is as follows: In the above formula , represents the scale factor. For a given the original sequence is segmented into coarse-grained vectors of length ; subsequently, the fuzzy entropy is calculated for the coarse-grained sequence at each scale .
5. A method for detecting faults in a distribution box according to claim 4, characterized in that, The multi-scale fuzzy entropy is: , and its mean value , where \(k = 1, 2, \ldots, n\); calculate its variance according to the fuzzy entropy, and its formula is: , arrange the variances in descending order, and select the fuzzy entropies of the first \(Z\) scales as the final features and input them into the GG clustering algorithm.
6. A power distribution box fault detection method according to claim 5, characterized in that, The selected sample set of fuzzy entropy is used as the input of the features of . If there are d features in the set elements , then . Let the cluster center vector of set Y be , and the membership matrix is defined as: , where c is the number of cluster centers; , representing the membership degree of the b-th sample to the a-th class, where . By iterating (U, V), the objective function J is minimized, and the expression of J is: , (1) In the above formula: M is the weighting exponent, generally taken as 2, is the distance measure to be calculated during clustering.
7. A method for detecting faults in a distribution box according to claim 6, characterized in that, The clustering algorithm is as follows: It also includes setting a termination tolerance e > 0 and randomly initializing the membership matrix as U. Subsequently, the cluster centers are calculated, and the formula is: , where l is an integer and l > 1; calculate the maximum likelihood estimation distance measure, and the formula is: , In the above formula is the covariance matrix of the i-th cluster, is the prior probability that the i-th cluster is selected; Update the membership matrix U, which is as follows: ; When is satisfied, terminate the iteration. If the condition is not met, let l = l + 1 and continue to iterate V and U until is satisfied, so that the function J obtains the minimum value.
8. A power distribution box fault detection method according to claim 1, characterized in that, Among them ; 。 9. An electronic device, comprising a memory and a processor, characterized in that, The memory stores a computer program, and the processor is set to run the computer program to execute the distribution box fault detection method according to any one of claims 1 to 8.
10. A readable storage medium, characterized in that, A program is stored thereon, and when the program is executed by the processor, the distribution box fault detection method according to any one of claims 1 to 8 is implemented.
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