A switch cabinet partial discharge monitoring system

Abstract

The application discloses a switch cabinet partial discharge monitoring system, comprising: a microphone array module for collecting acoustic signals in the switch cabinet; an acoustic gene library for storing partial discharge acoustic signals according to the types of the partial discharge acoustic signals in the switch cabinet; an identification module for comparing the collected acoustic signals in the switch cabinet with the partial discharge acoustic signals stored in the acoustic gene library to identify whether the collected acoustic signals in the switch cabinet are partial discharge acoustic signals; an output module for outputting the types and pointing information of the partial discharge acoustic signals when the identification result of the identification module is that the acoustic signals in the switch cabinet are partial discharge acoustic signals; and an indication module for indicating the source area of the partial discharge acoustic signals according to the pointing information output by the output module. The application can accurately identify the types of the partial discharge in the switch cabinet and accurately indicate the positions where the partial discharge occurs, thereby improving the identification accuracy and the maintenance efficiency of the partial discharge.

Description

Technical Field

[0001] This invention belongs to the field of switchgear technology, specifically relating to a partial discharge monitoring system for switchgear. Background Technology

[0002] Partial discharge in switchgear is a localized, non-penetrating discharge caused by insulation defects. Common types include internal air gaps, surface flashover, corona discharge, and poor contact discharge, which can affect the normal operation of switchgear to varying degrees.

[0003] However, in existing partial discharge detection technologies for switchgear, partial discharge detection often focuses on the changes in the operating status parameters of the switchgear itself. The detection results are rigid, the detection accuracy is fixed and constrained by the acquisition accuracy of the switchgear operating status parameter acquisition equipment. At the same time, it cannot quickly indicate the partial discharge problem detected. As a result, when a partial discharge problem occurs in the switchgear, maintenance personnel still need to spend a certain amount of time to find the location of the partial discharge, which affects the efficiency of partial discharge problem maintenance. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a partial discharge monitoring system for switchgear, which can accurately identify the type of partial discharge within the switchgear and accurately indicate the location where the partial discharge occurs, thereby improving the accuracy of partial discharge identification and maintenance efficiency.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a partial discharge monitoring system for switchgear, comprising: a microphone array module for collecting acoustic fingerprint signals within the switchgear; an acoustic fingerprint gene library for storing partial discharge acoustic fingerprint signals according to the type of the partial discharge acoustic fingerprint signals within the switchgear; an identification module for comparing the collected acoustic fingerprint signals within the switchgear with the partial discharge acoustic fingerprint signals stored in the acoustic fingerprint gene library to identify whether the collected acoustic fingerprint signals within the switchgear are partial discharge acoustic fingerprint signals; an output module for outputting the type and directional information of the partial discharge acoustic fingerprint signal when the identification result of the identification module indicates that the acoustic fingerprint signal within the switchgear is a partial discharge acoustic fingerprint signal; and an indication module for indicating the source area of ​​the partial discharge acoustic fingerprint signal according to the directional information output by the output module.

[0006] Furthermore, the microphone array module includes several miniature microphone components arranged in an array on the inner wall of the switch cabinet. The distribution area of ​​components and lines within the switch cabinet is determined by the frontal view of the inner wall of the switch cabinet, which serves as the deployment surface of the microphone array module. The corresponding area of ​​the distribution area of ​​components and lines within the switch cabinet under the frontal view of the inner wall of the switch cabinet, which serves as the deployment surface of the microphone array module, is used as the deployment area of ​​the microphone array module to deploy each miniature microphone component. In this case, under the frontal view of the inner wall of the switch cabinet, which serves as the deployment surface of the microphone array module, the deployment area of ​​the microphone array module overlaps with the distribution area of ​​components and lines within the switch cabinet, and the edges of the areas coincide.

[0007] Furthermore, the number of miniature microphone components in the microphone array module is one-third of the total number of components and circuits in the switch cabinet, rounded up.

[0008] Furthermore, the microphone array module is equipped with a control unit for adjusting the operating cycle of the microphone array module. The control unit is set with an initial operating cycle of the microphone array module. When the microphone array module is first run, it operates based on the set initial operating cycle.

[0009] Methods for adjusting the operating cycle of a microphone array module include:

[0010] Method 1: Adjust the operating cycle based on the temperature and humidity values ​​of the area where the switchgear is located;

[0011] ;

[0012] in, For the next running cycle; This is the current running cycle; This is the highest temperature monitored in the current cycle; Standard temperature; This represents the highest humidity level monitored during the current cycle. Standard humidity; These are temperature weights and humidity weights, respectively.

[0013] Method 2: Adjust the operating cycle based on the collected voiceprint signal spectrum;

[0014] Obtain the audioprint signal spectra collected by the microphone array module in the two most recent operations, and denot them as H1 and H2 based on time sequence. The ratio of the maximum amplitude to the minimum amplitude in H2 is denoted as h2, and the ratio of the maximum amplitude to the minimum amplitude in H1 is denoted as h1.

[0015] ;

[0016] Obtain the operating cycle T1 obtained by method one and the operating cycle T2 obtained by method two. If T1-T2≤0, then T1 is taken as the next operating cycle of the microphone array module; if T1-T2>0, then T2 is taken as the next operating cycle of the microphone array module.

[0017] Furthermore, the ratio of the current operating cycle to the initial operating cycle is monitored in real time. When the ratio is less than the set cycle threshold, an early warning signal is issued to prompt technicians to carry out maintenance.

[0018] Furthermore, the types of partial discharge acoustic signature signals include: internal air gap discharge, surface discharge, corona discharge, contact failure discharge, and insulation aging discharge.

[0019] Furthermore, the voiceprint gene database is updated in real time based on the recognition results of the recognition module; a temporary storage area is set in the voiceprint gene database to store the voiceprint signals collected from the switch cabinet, and when the recognition result of the recognition module is that the voiceprint signal in the switch cabinet is a partial discharge voiceprint signal, the voiceprint signal collected from the switch cabinet is moved from the temporary storage area to the storage area corresponding to the recognition result.

[0020] Furthermore, each miniature microphone component in the microphone array module collects a voiceprint signal from within the switch cabinet, namely a suspected partial discharge voiceprint signal. The identification module picks up the suspected partial discharge voiceprint signal with the highest intensity as the comparison target and performs a similarity comparison with the partial discharge voiceprint signals stored in the voiceprint gene library to determine the storage range with the highest comprehensive similarity to the suspected partial discharge voiceprint signal. The comprehensive similarity calculation result is then compared with a preset similarity judgment threshold. When the comprehensive similarity is greater than the preset similarity judgment threshold, the suspected partial discharge voiceprint signal is determined to be a partial discharge voiceprint signal, and the output module is triggered to run.

[0021] Furthermore, the type of partial discharge voiceprint signal output by the output module is the type of partial discharge voiceprint signal corresponding to the storage interval in the voiceprint gene library pointed to by the comprehensive similarity calculation result; the pointing information output by the output module is the position information of the micro microphone component in the microphone array module that collected the partial discharge voiceprint signal; wherein, the partial discharge voiceprint signal stored in the voiceprint gene library performs deduplication and duplicate processing in real time based on the operating cycle of the microphone array module, and the deduplication and duplicate processing condition is set to the similarity between two partial discharge voiceprint signals being greater than 99%.

[0022] Furthermore, the indicating module includes an indicating laser module for emitting a laser beam and an electric slide rail for moving the indicating laser module; after receiving the pointing information output by the output module, the electric slide rail moves the indicating laser module to the relative position of the partial discharge acoustic signature signal indicated by the pointing information, and triggers the indicating laser module to emit a laser beam; wherein, the laser beam emitted by the indicating laser module is perpendicular to the inner wall of the microphone array module in the switch cabinet, and the miniature microphone assembly corresponding to the pointing information of the partial discharge acoustic signature signal is located on the optical path of the laser beam, and the laser beam emitted by the indicating laser module is used to indicate the source area of ​​the partial discharge acoustic signature signal.

[0023] Furthermore, the electric slide rail is deployed on the inner wall of the switch cabinet opposite to the microphone array module. The maximum area of ​​the electric slide rail that indicates the movement of the laser module is not less than the deployment area of ​​the microphone array module from the perspective of the microphone array module.

[0024] Furthermore, it also includes a manual control unit located inside the switch cabinet for refreshing system operation after maintenance of the area where the partial discharge acoustic signal originates.

[0025] Furthermore, the microphone array module is internally connected to a control unit via a dielectric electrical connection. The microphone array module is also interconnected with a voiceprint gene database, a recognition module, and an output module via a wireless network. The output module is interconnected with an indicator module via a wireless network. The indicator module is interconnected with an electric slide rail and an indicator laser module via a wireless network. The indicator module is also interconnected with a manual control unit via a wireless network.

[0026] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0027] (1) The present invention uses a microphone array module for collecting acoustic signals in switch cabinets; an acoustic gene library for storing partial discharge acoustic signals according to the type of partial discharge acoustic signals in switch cabinets; an identification module for comparing the collected acoustic signals in switch cabinets with the partial discharge acoustic signals stored in the acoustic gene library to identify whether the collected acoustic signals in switch cabinets are partial discharge acoustic signals; an output module for outputting the type and direction information of partial discharge acoustic signals when the identification result of the identification module is that the acoustic signals in switch cabinets are partial discharge acoustic signals; and an indication module for indicating the source area of ​​partial discharge acoustic signals according to the direction information output by the output module. The present invention can accurately identify the type of partial discharge in switch cabinets and accurately indicate the location of partial discharge, thereby improving the accuracy of partial discharge identification and maintenance efficiency.

[0028] (2) During operation, the present invention accurately collects suspected partial discharge sound patterns in the switch cabinet through a multi-microphone array, and combines the partial discharge sound pattern feature library to achieve rapid identification of partial discharge type, effectively improving the sensitivity and accuracy of partial discharge monitoring. It optimizes the microphone deployment according to the distribution of components in the cabinet, and accurately locates the source area of ​​partial discharge with laser indication, which can significantly shorten the fault investigation time.

[0029] (3) The present invention dynamically adjusts the monitoring cycle by temperature, humidity and spectral characteristics, so as to reduce ineffective energy consumption while ensuring the timeliness of monitoring, and balance monitoring efficiency and energy consumption control.

[0030] (4) The voiceprint feature library of the present invention is continuously enriched through real-time updates and deduplication. Combined with manual inspection and verification, it improves the reliability of partial discharge identification. The manual control function makes it convenient for maintenance personnel to flexibly refresh the system, ensuring long-term stable operation. Compared with the existing technology, the system has higher sensitivity and more accurate positioning for partial discharge monitoring, effectively improving the safety of equipment operation and the convenience of maintenance. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of a partial discharge monitoring system for switchgear provided in an embodiment of the present invention. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0033] like Figure 1 As shown, a partial discharge monitoring system for switchgear includes: a microphone array module for collecting acoustic fingerprint signals within the switchgear; an acoustic fingerprint gene library for storing partial discharge acoustic fingerprint signals according to their type; an identification module for comparing the collected acoustic fingerprint signals within the switchgear with the partial discharge acoustic fingerprint signals stored in the acoustic fingerprint gene library to identify whether the collected acoustic fingerprint signals within the switchgear are partial discharge acoustic fingerprint signals; an output module for outputting the type and direction information of the partial discharge acoustic fingerprint signal when the identification result of the identification module indicates that the acoustic fingerprint signal within the switchgear is a partial discharge acoustic fingerprint signal; an indication module for indicating the source area of ​​the partial discharge acoustic fingerprint signal based on the direction information output by the output module; and a manual control unit for refreshing the system operation after maintenance of the source area of ​​the partial discharge acoustic fingerprint signal.

[0034] The microphone array module comprises several miniature microphone components arranged in an array on the inner wall of any side of the switch cabinet. The initial number of miniature microphone components in the microphone array module is set to one-third of the total number of components and wiring in the switch cabinet, rounded up. The total number of wiring can be calculated based on independent electrical connection paths, including main circuits, control circuits, and auxiliary circuits. Each complete path from the circuit breaker to the load is counted as one line.

[0035] When deploying the microphone array module, the spacing between each miniature microphone component is equal. The distribution area of ​​components and lines inside the switch cabinet is determined by the frontal view of the inner wall of the switch cabinet, which serves as the deployment surface of the microphone array module. The corresponding area of ​​the distribution area of ​​components and lines inside the switch cabinet under the frontal view of the inner wall of the switch cabinet, which serves as the deployment surface of the microphone array module, is used as the deployment area of ​​the microphone array module.

[0036] From a frontal view of the inner wall of the switch cabinet, which serves as the deployment surface for the microphone array module, the deployment area of ​​the microphone array module overlaps with the distribution area of ​​components and lines within the switch cabinet, and the edges of the areas coincide.

[0037] The microphone array module has an internal control unit, which is used to control the microphone array module to operate at a specified frequency.

[0038] The control unit sets the initial operating cycle of the microphone array module. The microphone array module runs for the first time based on the initial operating cycle, and the initial operating cycle is coordinated in real time through the following methods to control the real-time dynamic change of the microphone array module's operating cycle.

[0039] Methods for adjusting the operating cycle of a microphone array module include:

[0040] Method 1: Adjust the operating cycle based on the temperature and humidity values ​​of the area where the switchgear is located;

[0041] Real-time monitoring of temperature and humidity in the area where the switchgear is located; setting standard temperature and humidity thresholds; and comparing measured temperature and humidity values ​​with standard thresholds to coordinate the operating cycle of the microphone array module.

[0042] ;

[0043] in, For the next running cycle; This is the current running cycle; This is the highest temperature monitored in the current cycle; Standard temperature; This represents the highest humidity level monitored during the current cycle. Standard humidity; These are temperature weights and humidity weights, respectively. Their values ​​are user-defined on the system side and follow a set order. The sum is 1. All are positive numbers, and their initial values ​​are all 0.5.

[0044] Method 2: Adjust the operating cycle based on the collected voiceprint signal spectrum;

[0045] Obtain the audioprint signal spectra collected by the microphone array module in the two most recent operations, and denot them as H1 and H2 based on time sequence. The ratio of the maximum amplitude to the minimum amplitude in H2 is denoted as h2, and the ratio of the maximum amplitude to the minimum amplitude in H1 is denoted as h1.

[0046] ;

[0047] Simultaneously, the operating cycles obtained from Method 1 and Method 2 are acquired, and the smaller cycle from Method 1 and Method 2 is taken as the next operating cycle of the microphone array module. That is, the operating cycle T1 obtained from Method 1 and the operating cycle T2 obtained from Method 2 are acquired. If T1-T2≤0, then T1 is taken as the next operating cycle of the microphone array module; if T1-T2>0, then T2 is taken as the next operating cycle of the microphone array module.

[0048] The above formula compares the highest temperature and humidity of the current cycle with standard temperature and humidity thresholds, and calculates the next operating cycle by combining custom weights. This achieves real-time adaptation of temperature and humidity to the monitoring frequency. When the measured temperature and humidity deviate from the standard values, the operating cycle will be shortened (increased monitoring density) or extended (reduced redundant monitoring) accordingly. The weight parameters ensure that the influence ratio of temperature and humidity factors is controllable. This dynamic cycle adjustment mechanism of temperature and humidity coupling achieves "on-demand allocation" of monitoring frequency by quantifying the deviation between environmental parameters and standard thresholds and using a weighted fusion algorithm. It automatically densifies monitoring in harsh environments such as high temperature and high humidity, and adaptively relieves monitoring pressure when the environment is stable. This ensures high sensitivity capture in abnormal conditions and avoids resource waste in normal conditions, forming an intelligent monitoring rhythm driven by environmental perception.

[0049] This invention monitors the ratio of the current operating cycle to the initial operating cycle in real time. When the ratio is less than a set cycle threshold, it issues an early warning signal to prompt technicians to perform maintenance.

[0050] In this invention, the area where the switch cabinet is located is centered on the switch cabinet, and the radius is determined by the user-defined radius on the system side. Each change of the microphone array module in the next operating cycle is completed before the end of the current operating cycle and applied after being received in the current operating cycle.

[0051] During the process of the control unit regulating the operating cycle of the microphone array module, the ratio of the latest application operating cycle to the initial operating cycle is monitored in real time. When the ratio is less than the preset value, the switch cabinet maintenance personnel carry out offline maintenance on the switch cabinet. After the offline maintenance is completed, the control unit restores the microphone array module to the initial operating cycle and then re-coordinates the next operating cycle according to Method 1 and Method 2, and so on.

[0052] The voiceprint gene library is used to upload various types of partial discharge voiceprint signals (partial discharge voiceprint signals are also known as partial discharge voiceprint signals) of switchgear. Based on the type of partial discharge voiceprint signal, each partial discharge voiceprint signal is stored in a separate partition.

[0053] The types of partial discharge acoustic signals in switchgear include internal air gap discharge, surface discharge, corona discharge, poor contact of contacts, and insulation aging discharge.

[0054] The voiceprint gene database is updated in real time based on the partial discharge voiceprint signals determined by the system.

[0055] The voiceprint gene database has a temporary storage area. The voiceprint gene database stores the partial discharge voiceprint signals determined by the system based on the temporary storage area. The system user performs partial discharge location detection on the target switch cabinet based on the system output results. When the detection result indicates that there is a partial discharge problem, the partial discharge voiceprint signal is moved from the temporary storage area to the corresponding partition storage.

[0056] The identification module is used to receive suspected partial discharge voiceprint signals collected by the microphone array module. It compares the suspected partial discharge voiceprint signals with the partial discharge voiceprints stored in the voiceprint gene database to identify whether the suspected partial discharge voiceprint signals are indeed partial discharge voiceprint signals.

[0057] Each miniature microphone component in the microphone array module collects a voiceprint signal from the switch cabinet, which is a suspected partial discharge voiceprint signal. After receiving the suspected partial discharge voiceprint signals collected by each miniature microphone component in the microphone array module, the recognition module picks the suspected partial discharge voiceprint signal with the highest overall intensity as the comparison target. It compares the similarity with the partial discharge voiceprints stored in each storage interval of the voiceprint gene database to determine the storage interval with the highest comprehensive similarity to the suspected partial discharge voiceprint signal. The comprehensive similarity calculation result is compared with the preset judgment threshold. When the comprehensive similarity is greater than the preset judgment threshold, the suspected partial discharge voiceprint signal is determined to be a partial discharge voiceprint signal, which is the recognition result of the recognition module, and the output module is triggered to run.

[0058] ;

[0059] In the formula: The overall strength of the partial discharge acoustic signature signal; For high-frequency weights and time stability coefficients; This represents the maximum spectral amplitude in the partial discharge acoustic waveform signal. The average amplitude within the effective frequency band is defined by the system user and is initially set to 50-500kHz. The standard deviation of the amplitude of the partial discharge acoustic waveform signal; Peak frequency; This is the upper limit of the effective frequency band.

[0060] In acoustic signal analysis, the highest frequency threshold that can reflect partial discharge characteristics and whose signal-to-noise ratio meets the identification requirements is the key frequency boundary defined for the characteristics of ultrasonic signals of partial discharge in switchgear. In one example, the signal-to-noise ratio meeting the identification requirements means that the signal-to-noise ratio of the acoustic signal is ≥20dB. At this time, the frequency components can be effectively distinguished from the background noise, ensuring the accuracy of partial discharge feature extraction.

[0061] The initial setting is 0.6-0.9. Take the reciprocal of the amplitude fluctuation coefficient for three consecutive periods.

[0062] The above formula highlights the proportion of the maximum and average amplitude within the effective frequency band through high-frequency weighting, reflects the signal persistence with the time stability coefficient, and quantifies the "effective information content" of the signal by combining the ratio of peak frequency to the upper limit of the effective frequency band, providing an intensity benchmark for subsequent similarity comparison. By locking the core frequency band of the partial discharge signal through high-frequency weighting and filtering instantaneous interference noise with the time stability coefficient, the frequency distribution characteristics are incorporated into the intensity assessment dimension, constructing a three-dimensional intensity index of "amplitude-stability-spectrum". This design enables weak but continuous partial discharge signals to stand out, while suppressing the risk of misjudgment of sudden strong interference, providing a more accurate quantitative basis for signal screening.

[0063] The similarity comparison between suspected partial discharge voiceprint signals and partial discharge voiceprint signals stored in the voiceprint gene database follows the following order:

[0064]

[0065] in, The similarity between the suspected partial discharge acoustic signature signal X and the partial discharge acoustic signature signal Y; These are the weighting coefficients; The total number of samples; For the suspected partial discharge acoustic fingerprint signal X and the partial discharge acoustic fingerprint signal Y, the time-domain discrete sampling point values ​​are at the i-th sampling position. , To adjust the parameters; The normalized Fourier transform vectors of the suspected partial discharge acoustic signature signal X and the partial discharge acoustic signature signal Y. The wavelet energy distribution vectors of the suspected partial discharge acoustic signature signal X and the partial discharge acoustic signature signal Y; Describing the 1-norm, It represents the 2-norm.

[0066] All values ​​are positive and their sum is 1. The values ​​of each weight coefficient are user-defined on the system side. , The value can be adaptively selected within the range of 0.5-2.0 based on the frequency band distribution characteristics and energy attenuation rate of the partial discharge acoustic signal; for example, when the main frequency band of the partial discharge acoustic signal is concentrated in 1-10kHz, The value ranges from 0.8 to 1.2; when the energy decay rate is >0.5, The value ranges from 1.5 to 2.0; the specific range is automatically matched to the corresponding parameter based on the real-time detected spectral characteristics.

[0067] The above formula uses a weighted fusion of differences in discrete sampling points in the time domain, differences in normalized Fourier transform vectors, and differences in wavelet energy distribution vectors. Combined with adjustment parameters to adapt to the characteristics of different frequency bands, it finally outputs a comprehensive similarity value, which serves as the core criterion for signal matching. This enables high-precision identification of partial discharge signals. It incorporates time-domain waveform consistency, frequency-domain spectral distribution similarity, and energy-domain wavelet feature matching into a unified calculation framework. By flexibly adjusting the weights of each dimension through custom weights, the adjustment parameters adaptively match the frequency band characteristics of different types of partial discharge signals. This design allows the system to capture the high-frequency characteristics of air gap discharge and identify the energy decay law of insulation aging, significantly improving the signal matching accuracy under complex operating conditions.

[0068] Based on the above formula, the similarity between the suspected partial discharge voiceprint signal and the partial discharge voiceprint signals in each storage interval of the voiceprint gene database is calculated, and then the calculation results are weighted and averaged to be recorded as the comprehensive similarity.

[0069] The voiceprint gene database is updated in real time based on the recognition results of the recognition module. The voiceprint gene database is equipped with a temporary storage area to store the voiceprint signals collected from the switch cabinet. When the recognition module determines that the voiceprint signal in the switch cabinet is a partial discharge voiceprint signal, the collected voiceprint signal in the switch cabinet is moved from the temporary storage area to the storage area corresponding to the recognition result.

[0070] The output module is used to output the partial discharge acoustic pattern signal type and direction information when the identification module identifies the acoustic pattern signal in the switch cabinet as a partial discharge acoustic pattern signal.

[0071] The partial discharge voiceprint signal type output by the output module is such that the comprehensive similarity calculation result points to the partial discharge voiceprint signal type corresponding to the storage interval in the voiceprint gene library.

[0072] The partial discharge acoustic pattern signal output by the output module indicates the location information of the miniature microphone component in the microphone array module from which the partial discharge acoustic pattern signal originates.

[0073] Among them, the partial discharge voiceprint signals stored in the voiceprint gene bank are subjected to real-time deduplication and deduplication processing based on the operation cycle of the microphone array module. The deduplication and deduplication conditions are set to the similarity between two partial discharge voiceprint signals being greater than 99%.

[0074] The indicator module is used to receive the partial discharge acoustic pattern signal direction information output by the output module, and to indicate the source area of ​​the partial discharge acoustic pattern signal based on the partial discharge acoustic pattern signal direction information.

[0075] The lower level of the indicator module is equipped with a cross-shaped electric slide rail and an indicator laser module. The cross-shaped electric slide rail is used to move the indicator laser module, and the indicator laser module is used to emit a laser beam.

[0076] The cross-shaped electric slide rail is deployed on the inner wall of the switch cabinet opposite to the microphone array module. The maximum area of ​​the cross-shaped electric slide rail that indicates the movement of the laser module is not less than the deployment area of ​​the microphone array module from the perspective of the microphone array module.

[0077] After receiving the partial discharge acoustic pattern signal pointing information, the indicator module moves the laser module to the relative position of the partial discharge acoustic pattern signal pointing information via the cross-shaped electric slide rail, and triggers the indicator laser module to emit a laser beam.

[0078] Among them, the laser beam emitted by the indicator laser module is perpendicular to the inner wall where the microphone array module is located in the switch cabinet, and the micro microphone component corresponding to the partial discharge acoustic pattern signal pointing information is on the optical path of the laser beam. The display result of the laser beam emitted by the indicator laser module is the indication result of the source area of ​​the partial discharge acoustic pattern signal.

[0079] The manual control unit is used to control the system refresh operation.

[0080] It should be noted that the manual control unit can be integrated with electrical components that have automatic disconnection (pop-out, pop-out) functions, such as the principle of circuit breaker protection. After the system detects a partial discharge acoustic signal, the manual control unit automatically disconnects. After the switch cabinet manager completes the partial discharge problem repair, the switch cabinet manager manually operates the manual control unit to reset the manual control unit. When the manual control unit is reset, the control system is refreshed and put into operation.

[0081] The manual control unit is integrated inside the switch cabinet. Switch cabinet managers perform partial discharge maintenance on the switch cabinet based on the type of acoustic fingerprint signal output by the output module and the source area of ​​the partial discharge acoustic fingerprint signal indicated by the indicator module. After the maintenance is completed, the system operation is refreshed through the manual control unit.

[0082] The manual control unit is integrated inside the switch cabinet. Switch cabinet managers perform partial discharge maintenance on the switch cabinet based on the type of acoustic fingerprint signal output by the output module and the source area of ​​the partial discharge acoustic fingerprint signal indicated by the indicator module. After the maintenance is completed, the system operation is refreshed through the manual control unit.

[0083] In this invention, the microphone array module collects suspected partial discharge (PD) acoustic signature signals inside the switchgear in real time. The control unit synchronously controls the microphone array module to operate at a specified frequency. The acoustic signature gene database uploads various types of PD acoustic signature signals from the switchgear. Based on the PD acoustic signature signal type, each PD acoustic signature signal is distinguished and stored. Then, the identification module receives the suspected PD acoustic signature signals collected by the microphone array module and compares them with the PD acoustic signatures stored in the acoustic signature gene database to identify whether the suspected PD acoustic signature signal is indeed a PD acoustic signature signal. When the identification module identifies it as a PD acoustic signature signal, the output module outputs the PD acoustic signature signal type and directional information. The indication module further receives the PD acoustic signature signal directional information output by the output module and indicates the source area of ​​the PD acoustic signature signal based on the PD acoustic signature signal directional information. During the operation of the indication module, the cross-shaped electric slide rail moves the indication laser module in real time. The indication laser module synchronously emits a laser beam to indicate the source area of ​​the PD acoustic signature signal. Finally, the manual control unit controls the system to refresh the operation.

[0084] In this invention, a control unit is electrically connected to the microphone array module via a dielectric. The microphone array module is interconnected with a voiceprint gene database, a recognition module, and an output module via a wireless network. The output module is interconnected with an indicator module via a wireless network. The indicator module is interconnected with an electric slide rail and an indicator laser module via a wireless network. The indicator module is interconnected with a manual control unit via a wireless network.

[0085] This invention optimizes microphone array deployment to accurately collect partial discharge acoustic patterns, quickly identifies discharge types by comparing with a gene database, accurately locates the source area with laser indication, shortens fault diagnosis time, balances monitoring efficiency and energy consumption by dynamically adjusting the monitoring cycle, improves identification reliability by updating the gene database in real time to remove duplicates, and allows for easy updating after maintenance by manual control. It effectively achieves high-sensitivity monitoring and early warning of partial discharge in switchgear, improving equipment operation safety and maintenance convenience.

[0086] The following describes an application example of the switchgear partial discharge monitoring system described in the above embodiments.

[0087] A 10kV switchgear in a substation was equipped with the partial discharge monitoring system described in this invention. The switchgear contains 120 components and wiring. Accordingly, the microphone array module initially consists of 40 miniature microphone components, evenly spaced and arranged on the inner wall of the front of the switchgear. From a frontal view, its deployment area completely overlaps with the area containing the components and wiring within the cabinet, and their edges also coincide.

[0088] After the system starts up, the microphone array module begins to work according to the initial operating cycle. The initial operating cycle set by the control unit is 10 minutes. The weights in the control unit... The initial values ​​of both are 0.5, and their sum is 1.

[0089] During operation, the temperature and humidity of the area where the switchgear is located are monitored in real time using Method 1. Assuming the current operating cycle is 10 minutes, the highest temperature monitored in the current cycle is 35℃, the standard temperature is 30℃, the highest humidity (RH) monitored in the current cycle is 70%, and the standard humidity is 60%, the next operating cycle, after adjusting for temperature and humidity, is calculated to be 8 minutes.

[0090] Simultaneously, the latest two acquired voiceprint signal spectra H1 and H2 are obtained using Method 2. The ratio h2 of the maximum to minimum amplitude in H2 is 5, and the ratio h1 in H1 is 3. Based on this logic, the next operating cycle is calculated to be 7 minutes. The control unit takes the shorter cycle of the two, i.e., 7 minutes, as the next operating cycle.

[0091] The microphone array module collects voiceprint signals every 7 minutes, with each miniature microphone component collecting a suspected partial discharge voiceprint signal. The recognition module receives these signals and selects the one with the highest overall intensity as the comparison target. The high-frequency weighting of this signal... The initial value was set to 0.7. The time stability coefficient β was calculated to be 1.2 after three consecutive periods of amplitude fluctuation coefficient. After calculation, parameters such as maximum spectral amplitude, average amplitude within the effective frequency band, amplitude standard deviation, peak frequency, and upper limit of the effective frequency band were determined to meet the comparison requirements.

[0092] Subsequently, the suspected signal was compared with the partial discharge voiceprint signals in each storage region of the voiceprint gene database. By calculating parameters such as the discrete sampling point values ​​in the time domain, the normalized Fourier transform vector, and the wavelet energy distribution vector, the overall similarity with the corona discharge storage region was found to be 85%. The preset judgment threshold was 70%. Since 85% > 70%, the signal was determined to be a partial discharge voiceprint signal, and the type was corona discharge, triggering the output module to run.

[0093] The output module outputs a partial discharge acoustic signature signal of corona discharge type, and the directional information indicates the location of the miniature microphone component that acquired the signal. After receiving the directional information, the indicator module moves its lower-level cross-shaped motorized slide rail (deployed on the opposite side of the inner wall of the microphone array module) to the corresponding relative position, triggering the indicator laser module to emit a laser beam perpendicular to the inner wall of the microphone array module. The miniature microphone component is located on the laser beam path, and the area displayed by the laser beam is the corona discharge source area.

[0094] Switchgear maintenance personnel perform offline inspections based on the output type and indicated area. After inspection, the system is refreshed via the manual control unit integrated inside the switchgear. During system operation, the voiceprint gene database performs real-time deduplication of stored partial discharge voiceprint signals, and deduplication is performed when two signals have a similarity greater than 99%.

[0095] Afterwards, the system continues to monitor. When it detects that the ratio of the latest application running cycle to the initial running cycle is less than the preset value, the maintenance personnel will conduct offline maintenance again. After the maintenance is completed, the system will restore the initial running cycle and then re-coordinate the next running cycle according to the above logic, and so on.

[0096] In summary, the system described in the above embodiments accurately collects suspected partial discharge (PD) acoustic signatures within the switch cabinet using a multi-microphone array during operation. Combined with a PD acoustic signature feature database, it achieves rapid PD type identification, effectively improving the sensitivity and accuracy of PD monitoring. Optimizing microphone deployment based on the distribution of components within the cabinet, along with laser indication, allows for precise location of the PD source area, significantly shortening troubleshooting time. Dynamically adjusting the monitoring cycle based on temperature, humidity, and spectral characteristics ensures timely monitoring while reducing ineffective energy consumption, balancing monitoring efficiency and energy control. Furthermore, the acoustic signature feature database is continuously enriched through real-time updates and deduplication, and combined with manual inspection and verification, it enhances the reliability of PD identification. The manual control function allows maintenance personnel to flexibly update the system, ensuring long-term stable operation. Overall, compared to existing technologies, the system offers higher PD monitoring sensitivity and more accurate positioning, effectively improving equipment operational safety and maintenance convenience.

[0097] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A partial discharge monitoring system for switchgear, characterized in that, include: Microphone array module used to collect acoustic signature signals inside switch cabinets; A voiceprint gene library for storing partial discharge voiceprint signals according to the type of partial discharge voiceprint signal in the switch cabinet; An identification module is used to compare the collected acoustic fingerprint signals inside the switch cabinet with the partial discharge acoustic fingerprint signals stored in the acoustic fingerprint gene bank in order to identify whether the collected acoustic fingerprint signals inside the switch cabinet are partial discharge acoustic fingerprint signals. An output module for outputting the type and direction information of the partial discharge acoustic pattern signal when the identification result of the identification module is that the acoustic pattern signal in the switch cabinet is a partial discharge acoustic pattern signal; An indicator module used to indicate the source area of ​​partial discharge acoustic signature signals based on the directional information output by the output module; The microphone array module is equipped with a control unit for adjusting the operating cycle of the microphone array module. The control unit is set with an initial operating cycle of the microphone array module. When the microphone array module is first run, it operates based on the set initial operating cycle. Methods for adjusting the operating cycle of a microphone array module include: Method 1: Adjust the operating cycle based on the temperature and humidity values ​​of the area where the switchgear is located; in, For the next running cycle; This is the current running cycle; This is the highest temperature monitored in the current cycle; Standard temperature; This represents the highest humidity level monitored during the current cycle. Standard humidity; These are temperature weights and humidity weights, respectively. Method 2: Adjust the operating cycle based on the collected voiceprint signal spectrum; Obtain the audioprint signal spectra collected by the microphone array module in the two most recent operations, and denot them as H1 and H2 based on time sequence. The ratio of the maximum amplitude to the minimum amplitude in H2 is denoted as h2, and the ratio of the maximum amplitude to the minimum amplitude in H1 is denoted as h1. Obtain the operating cycle T1 obtained by method one and the operating cycle T2 obtained by method two. If T1-T2≤0, then T1 is taken as the next operating cycle of the microphone array module; if T1-T2>0, then T2 is taken as the next operating cycle of the microphone array module.

2. The switchgear partial discharge monitoring system according to claim 1, characterized in that, The microphone array module includes several miniature microphone components arranged in an array on the inner wall of the switch cabinet. The distribution area of ​​components and lines inside the switch cabinet is determined by the frontal view of the inner wall of the switch cabinet, which serves as the deployment surface of the microphone array module. From the frontal view of the inner wall of the switch cabinet, which serves as the deployment surface for the microphone array module, the corresponding area of ​​the component and wiring distribution area inside the switch cabinet is used as the deployment area for the microphone array module, where each miniature microphone component is deployed. From a frontal view of the inner wall of the switch cabinet, which serves as the deployment surface for the microphone array module, the deployment area of ​​the microphone array module overlaps with the distribution area of ​​components and lines within the switch cabinet, and the edges of the areas coincide.

3. The switchgear partial discharge monitoring system according to claim 1, characterized in that, The number of miniature microphone components in the microphone array module is one-third of the total number of components and lines in the switch cabinet, rounded up.

4. The switchgear partial discharge monitoring system according to claim 1, characterized in that, The system monitors the ratio of the current operating cycle to the initial operating cycle in real time. When the ratio is less than the set cycle threshold, it issues an early warning signal to prompt technicians to perform maintenance.

5. The partial discharge monitoring system for switchgear according to claim 1, characterized in that, Types of partial discharge acoustic signatures include: internal air gap discharge, surface discharge, corona discharge, poor contact discharge, and insulation aging discharge.

6. The switchgear partial discharge monitoring system according to claim 1, characterized in that, The voiceprint gene database is updated in real time based on the recognition results of the recognition module. The voiceprint gene database is equipped with a temporary storage area to store the voiceprint signals collected from the switch cabinet. When the recognition module determines that the voiceprint signal in the switch cabinet is a partial discharge voiceprint signal, the collected voiceprint signal in the switch cabinet is moved from the temporary storage area to the storage area corresponding to the recognition result.

7. The switchgear partial discharge monitoring system according to claim 1, characterized in that, Each miniature microphone component in the microphone array module collects a voiceprint signal from the switch cabinet, namely a suspected partial discharge voiceprint signal. The identification module picks up the suspected partial discharge voiceprint signal with the highest intensity as the comparison target and compares it with the partial discharge voiceprint signals stored in the voiceprint gene library to determine the storage range with the highest comprehensive similarity to the suspected partial discharge voiceprint signal. The comprehensive similarity calculation result is compared with a preset similarity judgment threshold. When the comprehensive similarity is greater than the preset similarity judgment threshold, the suspected partial discharge voiceprint signal is determined to be a partial discharge voiceprint signal, and the output module is triggered to run.

8. The switchgear partial discharge monitoring system according to claim 7, characterized in that, The type of partial discharge voiceprint signal output by the output module is the type of partial discharge voiceprint signal corresponding to the storage interval in the voiceprint gene library pointed to by the comprehensive similarity calculation result; the directional information output by the output module is the position information of the micro microphone component in the microphone array module that collected the partial discharge voiceprint signal. Among them, the partial discharge voiceprint signals stored in the voiceprint gene library are subjected to real-time deduplication and deduplication processing based on the operation cycle of the microphone array module. The deduplication and deduplication conditions are set to the similarity between two partial discharge voiceprint signals being greater than 99%.

9. The switchgear partial discharge monitoring system according to claim 8, characterized in that, The indicating module includes an indicating laser module for emitting a laser beam and an electric slide rail for moving the indicating laser module; after receiving the pointing information output by the output module, the electric slide rail moves the indicating laser module to the relative position of the partial discharge acoustic signature signal indicated by the pointing information, and triggers the indicating laser module to emit a laser beam. The laser beam emitted by the indicator laser module is perpendicular to the inner wall of the microphone array module in the switch cabinet, and the miniature microphone component corresponding to the directional information of the partial discharge acoustic pattern signal is located on the optical path of the laser beam. The laser beam emitted by the indicator laser module is used to indicate the source area of ​​the partial discharge acoustic pattern signal.

10. The switchgear partial discharge monitoring system according to claim 9, characterized in that, The electric slide rail is deployed on the inner wall of the switch cabinet opposite to the microphone array module. The maximum area of ​​the electric slide rail that indicates the movement of the laser module is not less than the deployment area of ​​the microphone array module from the perspective of the microphone array module.

11. The switchgear partial discharge monitoring system according to claim 1, characterized in that, It also includes a manual control unit located inside the switch cabinet, used to refresh the system operation after maintenance of the area where the partial discharge acoustic signal originates.

12. The switchgear partial discharge monitoring system according to claim 11, characterized in that, The microphone array module is internally connected to a control unit via a dielectric. The microphone array module is also interconnected with a voiceprint gene database, a recognition module, and an output module via a wireless network. The output module is interconnected with an indicator module via a wireless network. The indicator module is interconnected with an electric slide rail and an indicator laser module via a wireless network. The indicator module is also interconnected with a manual control unit via a wireless network.

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