A method, system and storage medium for detecting multi-channel partial discharge signals

Abstract

The present application relates to the technical field of partial discharge detection, and discloses a detection method, system and storage medium of a multi-channel partial discharge signal, the method: initialize the first to third channels, and multiple channels are all closed; start the second channel, obtain the second channel interference signal; close the second channel, start the third channel, obtain the third channel interference signal; close the third channel, start the first channel, and obtain the first detection signal; close the first channel, calculate and obtain the first partial discharge data based on the first detection signal; output the first partial discharge data; calculate and measure the second interference data according to the second channel interference signal, and calculate and obtain the third interference data according to the third channel interference signal; match the second correction data according to the second interference data, and correct the detection parameters of the second channel; match the third correction data according to the third interference data, and correct the detection parameters of the third channel. The present application reduces the detection error caused by the influence of setting parameters in multiple channels.

Description

Technical Field

[0001] The present application relates to the technical field of partial discharge detection, and in particular to a detection method, system and storage medium for multi-channel partial discharge signals. Background Art

[0002] The main function of partial discharge monitoring equipment is to conduct real-time detection of the insulation status of power equipment. Partial discharge monitoring equipment is divided into multiple types according to different detection signals. The types of detection signals include: ultrasonic, transient ground voltage, ultra-high frequency, etc. Different detection signals belong to different measurement frequency bands of partial discharge monitoring equipment.

[0003] Different partial discharge monitoring equipment is susceptible to interference from electromagnetic waves or interference signals in other frequency bands. Therefore, most companies develop a partial discharge monitoring equipment product for a signal, with the purpose of detecting the partial discharge signal corresponding to the signal. If you want to develop a product that can simultaneously detect ultrasonic, transient ground voltage and ultra-high frequency partial discharge signals, you need to set up multiple monitoring channels in a product. Each monitoring channel has its own setting parameters, such as filtering parameters. Detecting the signal of the current channel will affect the setting parameters in other channels. The detection accuracy of multi-channel partial discharge monitoring equipment needs to be improved. Summary of the invention

[0004] In order to reduce the detection error caused by the influence of setting parameters in multiple channels, the present application provides a multi-channel partial discharge signal detection method, system and storage medium.

[0005] In a first aspect, the present application provides a method for detecting a multi-channel partial discharge signal, which adopts the following technical solution:

[0006] A method for detecting a multi-channel partial discharge signal comprises the following steps:

[0007] Initializing the first channel, the second channel and the third channel, wherein the first channel, the second channel and the third channel are all in a closed state;

[0008] Based on the acquired first channel start signal, start the second channel, acquire the second channel interference signal, close the second channel, start the third channel, acquire the third channel interference signal, and close the third channel;

[0009] Based on the obtained first channel working signal, start the first channel to obtain a first detection signal;

[0010] Based on the acquired first channel stop signal, close the first channel, calculate and obtain first partial discharge data based on the first detection signal; and output the first partial discharge data;

[0011] The second interference data is measured according to the second channel interference signal, and the third interference data is calculated according to the third channel interference signal;

[0012] Match the second correction data according to the second interference data, and use the second correction data to correct the detection parameters of the second channel; match the third correction data according to the third interference data, and use the third correction data to correct the detection parameters of the third channel.

[0013] By adopting the above technical solution, the first channel, the second channel and the third channel are used to detect partial discharge signals. First, the interference signal is obtained by starting and closing different channels, and then correction is performed based on these interference signals to improve the accuracy of subsequent detection signals. Finally, the actual detection signal is obtained when the first channel is working, and the partial discharge data is calculated. By dynamically adjusting the detection parameters, the detection accuracy and anti-interference ability of the multi-channel partial discharge monitoring equipment are improved.

[0014] Optionally, the method further comprises the following steps:

[0015] After closing the first channel, restarting the second channel and the third channel to obtain a second channel interference correction signal and a third channel interference correction signal;

[0016] The second interference correction data is calculated according to the second channel interference correction signal, and the third interference correction data is calculated according to the third channel interference correction signal;

[0017] The second correction data is calculated by weighted average based on the second interference data and the second interference correction data, and the third correction data is calculated by weighted average based on the third interference data and the third interference correction data.

[0018] By adopting the above technical solution and adding the step of acquiring the interference signal for a second time and calculating the correction data by weighted average, the accuracy and stability of the multi-channel partial discharge monitoring equipment can be further improved.

[0019] Optionally, the method further comprises the following steps:

[0020] When the second channel or the third channel is started according to the corresponding start signal, the first channel is started, the first channel interference signal is obtained, and the first channel is closed;

[0021] Calculating and measuring first interference data according to the first channel interference signal, matching first correction data according to the first interference data, and correcting the detection parameters of the first channel using the first correction data;

[0022] Extracting a first interference signal energy value according to the first channel interference signal, extracting a second interference signal energy value according to the second channel interference signal, and extracting a third interference signal energy value according to the third channel interference signal;

[0023] Calculate the ratio of the first interference signal energy value, the second interference signal energy value and the third interference signal energy value as an energy ratio;

[0024] The duration of the first channel detecting the interference signal is the first duration, the duration of the second channel detecting the interference signal is the second duration, and the duration of the third channel detecting the interference signal is the third duration; the sum of the first duration, the second duration and the third duration is a fixed acquisition time value; the first duration corresponds to the first interference signal energy value, the second duration corresponds to the second interference signal energy value, and the third duration corresponds to the third interference signal energy value;

[0025] The values ​​of the first duration, the second duration and the third duration are adjusted according to the energy ratio.

[0026] By adopting the above technical solution, on the basis of the original multi-channel partial discharge signal detection method, the steps of measuring the mutual interference between channels, calculating the energy ratio and adjusting the duration are further added. This improvement aims to optimize the performance of multi-channel partial discharge monitoring equipment by more finely managing the interference signal and detection duration of each channel.

[0027] Optionally, the method further comprises the following steps:

[0028] When the first channel performs detection, the ratio between the energy value of the second interference signal and the energy value of the third interference signal is calculated as a first calculated ratio;

[0029] According to the first calculated ratio, positively correlatedly adjust the ratio between the weights of the second interference data and the second interference correction data; the larger the first calculated ratio, the larger the ratio between the weights of the second interference data and the second interference correction data; the smaller the first calculated ratio, the smaller the ratio between the weights of the second interference data and the second interference correction data;

[0030] According to the first calculated ratio, the ratio between the weights of the third interference data and the third interference correction data is anti-correlatedly adjusted; the larger the first calculated ratio is, the smaller the ratio between the weights of the third interference data and the third interference correction data is; the smaller the first calculated ratio is, the larger the ratio between the weights of the third interference data and the third interference correction data is.

[0031] By adopting the above technical solution and adding a step of dynamically adjusting the weight according to the first calculated ratio, the performance and accuracy of the multi-channel partial discharge monitoring device can be further improved.

[0032] Optionally, the method further comprises the following steps:

[0033] When the first channel performs detection, a second interference signal frequency value is extracted according to the second channel interference signal, a third interference signal frequency value is extracted according to the third channel interference signal, and a ratio between the second interference signal frequency value and the third interference signal frequency value is calculated as a second calculated ratio;

[0034] According to the second calculated ratio, positively correlatedly adjust the ratio between the weights of the second interference data and the second interference correction data; the larger the second calculated ratio, the larger the ratio between the weights of the second interference data and the second interference correction data; the smaller the second calculated ratio, the smaller the ratio between the weights of the second interference data and the second interference correction data;

[0035] According to the second calculated ratio, the ratio between the weights of the third interference data and the third interference correction data is anti-correlatedly adjusted; the larger the second calculated ratio is, the smaller the ratio between the weights of the third interference data and the third interference correction data is; the smaller the second calculated ratio is, the larger the ratio between the weights of the third interference data and the third interference correction data is.

[0036] By adopting the above technical solution, a new step of adjusting the weight according to the ratio of the interference signal frequency value is added. The introduction of this step not only considers the energy value of the interference signal, but also considers the frequency characteristics, thereby more comprehensively evaluating the interference situation of each channel.

[0037] Optionally, the method further comprises the following steps:

[0038] A first shielding coil is disposed next to the first channel, a second shielding coil is disposed next to the second channel, and a third shielding coil is disposed next to the third channel; the first shielding coil, the second shielding coil and the third shielding coil are all in an open state;

[0039] Based on the acquired first channel start signal, close the first shielding coil, start the second channel, acquire the second channel interference signal, close the second channel, start the third channel, acquire the third channel interference signal, and close the third channel; start the first shielding coil after outputting the first partial discharge data;

[0040] The open state is grounded or maintains the set voltage value.

[0041] By adopting the above technical solution, mutual interference between channels is reduced by shielding coils, thereby improving the accuracy of detection.

[0042] Optionally, the method further comprises the following steps:

[0043] If the on state is to maintain the set voltage value, the voltage value of the shielding coil of the corresponding channel is adjusted in positive correlation with the energy value of the interference signal of the corresponding channel; the greater the energy value of the interference signal of the corresponding channel, the greater the voltage value of the shielding coil of the corresponding channel; the smaller the energy value of the interference signal of the corresponding channel, the smaller the voltage value of the shielding coil of the corresponding channel.

[0044] By adopting the above technical solution, the mutual interference between channels can be more effectively reduced by adjusting the voltage value of the shielding coil, thereby improving the accuracy of detection.

[0045] Optionally, the method further comprises the following steps:

[0046] There are multiple shielding coils corresponding to the channel;

[0047] The number of shielding coils of the corresponding channel is adjusted in positive correlation with the energy value of the interference signal of the corresponding channel; the greater the energy value of the interference signal of the corresponding channel, the greater the number of shielding coils of the corresponding channel; the smaller the energy value of the interference signal of the corresponding channel, the smaller the number of shielding coils of the corresponding channel.

[0048] By adopting the above technical solution, the mutual interference between channels can be more effectively controlled by increasing or decreasing the number of shielding coils, thereby further improving the accuracy of detection.

[0049] In a second aspect, the present application provides a multi-channel partial discharge signal detection system, which adopts the following technical solution:

[0050] A multi-channel partial discharge signal detection system comprises a processor, wherein the processor executes the steps of any one of the multi-channel partial discharge signal detection methods described above.

[0051] In a third aspect, the present application provides a storage medium, which adopts the following technical solution:

[0052] A storage medium stores a program, wherein the program, when executed by a processor, implements the steps of any one of the above-mentioned methods for detecting multi-channel partial discharge signals.

[0053] In summary, the present application includes at least one of the following beneficial technical effects:

[0054] Three channels are used to detect partial discharge signals. First, interference signals are obtained by starting and closing different channels, and then corrections are made based on these interference signals to improve the accuracy of subsequent detection signals. Finally, the actual detection signal is obtained when the first channel is working, and partial discharge data is calculated; the influence of interference signals is reduced by mutual verification and correction between multiple channels. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 The present invention is a step diagram of a method for detecting a multi-channel partial discharge signal.

[0056] Figure 2 This is a diagram of the steps of newly adding a second acquisition of interference signals and performing weighted average calculation of correction data.

[0057] Figure 3 It is a step-by-step diagram for measuring mutual interference between channels, calculating energy ratios, and adjusting duration.

[0058] Figure 4 It is a step diagram for dynamically adjusting the weight according to the first calculated ratio.

[0059] Figure 5 It is a step diagram for adjusting the weights according to the ratio of the interference signal frequency values.

[0060] Figure 6 This is a diagram of the steps to reduce mutual interference between channels by shielding the coils. DETAILED DESCRIPTION

[0061] Embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings.

[0062] In the description of this specification, the description with reference to the terms "certain embodiments", "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0063] The present application embodiment discloses a method for detecting a multi-channel partial discharge signal. Figure 1 , including the following steps:

[0064] Initialize the first channel, the second channel, and the third channel, all of which are in a closed state; to ensure that all channels are in a known and consistent state before the detection begins.

[0065] Based on the first channel start signal obtained, the second channel is started, the second channel interference signal is obtained, and the second channel is turned off; the third channel is started, the third channel interference signal is obtained, and the third channel is turned off. The purpose is to record the potential interference of other channels before the main detection channel, that is, the first channel, starts working, so as to perform interference correction later. Among them, the second channel interference signal and the third channel interference signal refer to all other non-target signals received by the channel in addition to the target partial discharge signal when a specific channel (such as the first channel) is activated. These signals come from the external environment, electromagnetic interference inside the equipment, and the noise of the channel itself.

[0066] Based on the acquired first channel working signal, the first channel is started to acquire a first detection signal.

[0067] Based on the obtained first channel stop signal, the first channel is closed, and the first partial discharge data is calculated based on the first detection signal; the first partial discharge data is output. Among them, the process of calculating the first partial discharge data adopts the calculation method in the prior art. Usually, the following method is used: First, the partial discharge signal in the electrical equipment is obtained through a sensor, such as an ultrasonic sensor, a high-frequency current sensor, etc. These signals usually exist in the form of voltage or current and contain various characteristic information of partial discharge. The original signal obtained often contains noise and interference, so preprocessing is required to improve the signal-to-noise ratio of the signal. The preprocessing process includes filtering, denoising, amplification and other steps to ensure the accuracy of subsequent analysis. Based on the extracted characteristic information, the amount of electricity or energy of the partial discharge can be calculated. This is usually achieved by comparing the characteristic information with a known discharge model or calibration data. In the calculation process, it is necessary to consider the influence of multiple factors, such as the type of discharge, the properties of the insulating material, the electric field strength, etc. Finally, the calculated partial discharge data needs to be further analyzed and diagnosed. This includes judging the severity of the discharge, determining the location and cause of the discharge, and evaluating the degree of damage to the insulating material. Through data analysis, a strong basis can be provided for the maintenance, overhaul and replacement of equipment.

[0068] The second interference data is measured according to the interference signal of the second channel, and the third interference data is calculated according to the interference signal of the third channel. Among them, the calculation method for calculating the second interference data includes signal extraction algorithms such as smoothing filtering + peak detection. Obtain the interference signal from the second channel. This signal contains various noises and interferences, such as electromagnetic interference, background noise, etc. Apply the smoothing filtering algorithm to preprocess the interference signal. The purpose of smoothing filtering is to reduce noise and random fluctuations and make the signal smoother. Common smoothing filtering methods include moving average filtering, Gaussian filtering, etc. By selecting appropriate filters and parameters, high-frequency noise can be effectively removed while retaining the main features of the signal. Peak detection is performed on the signal after smoothing filtering. The purpose of peak detection is to find the local maximum value in the signal, which corresponds to the peak value of the interference signal. Peak detection can be achieved by setting a threshold, calculating the derivative of the signal, etc. Through peak detection, the key feature points in the signal can be extracted to provide a basis for subsequent interference data calculation. Based on the results of peak detection, the interference data of the second channel is calculated. Including parameters such as the peak value of the interference signal, the time when the peak value occurs, and the interval between peak values. These parameters together constitute the second interference data for subsequent analysis and evaluation.

[0069] Match the second correction data according to the second interference data, and use the second correction data to correct the detection parameters of the second channel. Match the third correction data according to the third interference data, and use the third correction data to correct the detection parameters of the third channel. Among them, the method of matching the correction data according to the interference data includes a template matching method, especially a second matching template. The interference data of the second channel is calculated by the signal extraction algorithms such as smoothing filtering and peak detection mentioned above. Define the second matching template according to known or preset standards. This template contains a series of expected interference data features, such as peak range, peak interval, waveform characteristics, etc. Match the second interference data with the second matching template. This can be achieved by calculating the similarity or distance between the interference data and the template. Common matching methods include Euclidean distance, Mahalanobis distance, correlation coefficient, etc. According to the matching results, select the best matching correction data from the preset correction data set as the second correction data. These correction data include parameters such as gain, offset, filter, etc. required to adjust the detection parameters. Use the second correction data to adjust the detection parameters of the second channel. It involves adjusting the gain of the amplifier, the offset and gain of the ADC, the parameters of the filter, etc., to ensure that the detected signal is more accurate and reliable.

[0070] Therefore, three channels are used to detect partial discharge signals. First, interference signals are obtained by starting and closing different channels, and then corrections are made based on these interference signals to improve the accuracy of subsequent detection signals. Finally, the actual detection signal is obtained when the first channel is working, and partial discharge data is calculated; the influence of interference signals is reduced by mutual verification and correction between multiple channels. By dynamically adjusting the detection parameters, the detection accuracy and anti-interference ability of the multi-channel partial discharge monitoring equipment are improved.

[0071] Reference Figure 2 , the method further comprises the following steps:

[0072] After closing the first channel, start the second and third channels again to obtain the second channel interference correction signal and the third channel interference correction signal; the purpose is to re-evaluate the interference conditions of other channels after the first channel detection is completed to reflect any impact on other channels during the first channel detection process.

[0073] The second interference correction data is calculated based on the interference correction signal of the second channel, and the third interference correction data is calculated based on the interference correction signal of the third channel; the interference correction data of the second and third channels are calculated based on the interference correction signals obtained for the second time. These data will be used for subsequent weighted average calculation.

[0074] The second correction data is calculated by weighted average based on the second interference data and the second interference correction data, and the third correction data is calculated by weighted average based on the third interference data and the third interference correction data. The weighted average method is used to combine the initially acquired interference data and the secondly acquired interference correction data to calculate the correction data of the second and third channels. The weighted average can comprehensively consider the interference conditions at different time points, so as to more accurately reflect the actual interference level of the channel. By acquiring the interference signal twice and performing weighted average calculation, the influence of random interference and dynamic changes in the detection process on the detection results can be more effectively eliminated, thereby improving the accuracy of the detection. The weighted average method can smooth out some sudden interference signals, making the detection results more stable and reliable. This method can adapt to the complexity and diversity of partial discharge signals in different environments, and improve the applicability of the equipment in different application scenarios.

[0075] For example, the second interference data D2=10 is a measured value;

[0076] The second interference correction data C2′=8, wherein C2′ is a known correction value updated last time or a preset correction value;

[0077] The second interference data weight wD=0.5; the second interference correction data weight wC=0.5; the sum of the weights should be 1, that is, wD+wC=1. The weights can be set according to actual conditions, such as based on data reliability, measurement conditions, etc., and the initial values ​​are all 0.5.

[0078] The second correction data C2=wD×D2+wC×C2′=9.

[0079] The third interference data D3=12 is the measured value;

[0080] The third interference correction data C3′=10, wherein C3′ is a known correction value updated last time or a preset correction value;

[0081] The third interference data weight wD=0.5; the third interference correction data weight wC=0.5; the sum of the weights should be 1, that is, wD+wC=1. The weights can be set according to actual conditions, such as based on data reliability, measurement conditions, etc., and the initial values ​​are all 0.5.

[0082] The third correction data=wD×D3+wC×C3′=11.

[0083] By adding the steps of acquiring interference signals for a second time and calculating correction data by weighted average, the accuracy and stability of multi-channel partial discharge monitoring equipment can be further improved.

[0084] The channel can be opened and closed by setting a transistor switch circuit in the circuit, and the opening and closing can be achieved through the control system of the detection device.

[0085] Reference Figure 3 , the method further comprises the following steps:

[0086] When the second channel or the third channel receives the corresponding start signal, the first channel is started, the interference signal of the first channel is obtained, and the first channel is closed; the purpose is to measure the interference of other channels on the first channel when they are working, so as to understand the mutual influence between channels.

[0087] First interference data is calculated and measured according to the first channel interference signal, first correction data is matched according to the first interference data, and the first correction data is used to correct the detection parameters of the first channel.

[0088] The energy value of the first interference signal is extracted from the first channel interference signal, the energy value of the second interference signal is extracted from the second channel interference signal, and the energy value of the third interference signal is extracted from the third channel interference signal; these energy values ​​reflect the intensity and duration of the interference signals of each channel. Among them, the energy value corresponding to the interference signal is: the corresponding signal is divided into several time windows, and then the signal in each time window is squared and summed to obtain the energy value in the time window. Finally, the energy values ​​of all time windows are averaged or integrated to obtain the total energy value of the entire signal. The energy value is reflected in the graph as the area corresponding to the interference signal curve.

[0089] The ratio among the energy value of the first interference signal, the energy value of the second interference signal and the energy value of the third interference signal is calculated as the energy ratio; the purpose is to evaluate the relative strength of the interference signals of each channel and provide a basis for subsequent duration adjustment.

[0090] The duration of the first channel detecting the interference signal is the first duration, the duration of the second channel detecting the interference signal is the second duration, and the duration of the third channel detecting the interference signal is the third duration; the sum of the first duration, the second duration and the third duration is a fixed acquisition time value; the first duration corresponds to the first interference signal energy value, the second duration corresponds to the second interference signal energy value, and the third duration corresponds to the third interference signal energy value.

[0091] The values ​​of the first duration, the second duration and the third duration are adjusted according to the energy ratio; the purpose is to dynamically allocate the detection duration according to the strength of the interference signal of each channel within the fixed acquisition time value to optimize the overall detection efficiency. If the energy ratio of a channel is high, it means that the interference signal of the channel is strong, and more detection time needs to be allocated to ensure that the interference signal can be accurately captured. On the contrary, if the energy ratio of a channel is low, its detection time can be appropriately reduced. The fixed acquisition time value ensures the stability of the total detection time, while the detection time of each channel is flexibly adjusted according to its real-time interference situation. By dynamically adjusting the detection time of each channel, the total detection time can be used more effectively, thereby improving the detection efficiency. This method can adapt to the changes in the intensity and duration of the interference signal of each channel under different environments, and improve the adaptability of the equipment in different application scenarios. By finely managing the interference signal and detection time of each channel, the performance of the multi-channel partial discharge monitoring equipment can be further optimized.

[0092] The specific method of adjusting the duration can be to allocate it in proportion, that is, to determine the proportion of the detection duration that each channel should occupy according to the energy ratio of each channel. It can also be to set a threshold, and when the energy ratio of a channel exceeds the threshold, its detection duration is increased; when the energy ratio is lower than the threshold, its detection duration is reduced.

[0093] Based on the original multi-channel partial discharge signal detection method, the measurement of mutual interference between channels, calculation of energy ratio and duration adjustment steps are further added. The purpose is to optimize the performance of multi-channel partial discharge monitoring equipment by more finely managing the interference signal and detection duration of each channel.

[0094] Reference Figure 4 , the method further comprises the following steps:

[0095] When the first channel performs detection, the ratio between the energy value of the second interference signal and the energy value of the third interference signal is calculated as the first calculated ratio; the purpose is to evaluate the relative strength of the interference signals of the second and third channels and provide a basis for the subsequent adjustment of weights.

[0096] When the first channel performs detection, the ratio between the energy value of the second interference signal and the energy value of the third interference signal is calculated, which is recorded as the first calculated ratio R1. R1=the energy value of the second interference signal / the energy value of the third interference signal.

[0097] According to the first calculated ratio, the ratio between the weights of the second interference data and the second interference correction data is positively correlated and adjusted. The larger the first calculated ratio, the larger the ratio between the weights of the second interference data and the second interference correction data; the smaller the first calculated ratio, the smaller the ratio between the weights of the second interference data and the second interference correction data. The larger the first calculated ratio, the stronger the interference signal of the second channel is. Therefore, the second interference data and the second interference correction data are given a larger weight to more accurately reflect the actual situation of the second channel.

[0098] According to the first calculated ratio R1, the ratio between the weights of the second interference data (denoted as D2) and the second interference correction data (denoted as C2) is positively correlated and adjusted.

[0099] Set an initial weight ratio wD2 / wC2=1; where wD2 and wC2 are the weights of D2 and C2 respectively.

[0100] When R1 increases, the ratio of wD2 to wC2 increases, that is, wD2 / wC2 also increases.

[0101] When R1 decreases, the ratio of wD2 to wC2 decreases, that is, wD2 / wC2 also decreases.

[0102] This positive correlation regulation can be achieved through an increasing function relationship, for example: wD2 / wC2=k1×R1; where k1 is a constant.

[0103] According to the first calculation ratio, the ratio between the weights of the third interference data and the third interference correction data is adjusted in an anti-correlation manner; the larger the first calculation ratio is, the smaller the ratio between the weights of the third interference data and the third interference correction data is; the smaller the first calculation ratio is, the larger the ratio between the weights of the third interference data and the third interference correction data is. That is, the larger the first calculation ratio is, the relatively weaker the interference signal of the third channel is, and thus the third interference data and the third interference correction data are given smaller weights.

[0104] According to the first calculated ratio R1, the ratio between the weights of the third interference data (denoted as D3) and the third interference correction data (denoted as C3) is anti-correlatedly adjusted.

[0105] Set an initial weight ratio wD3 / wC3=1, where wD3 and wC3 are the weights of D3 and C3 respectively.

[0106] When R1 increases, the ratio of wD3 to wC3 decreases, that is, wD3 / wC3 decreases.

[0107] When R1 decreases, the ratio of wD3 to wC3 increases, that is, wD3 / wC3 increases.

[0108] This anti-correlation regulation can be achieved through a decreasing function relationship, for example: wD3 / wC3=k2 / R1; where k2 is another constant.

[0109] By dynamically adjusting the weights according to the ratio of the energy values ​​of the interference signals, the actual conditions of each channel can be more accurately reflected, thereby improving the accuracy of detection. This method can flexibly adjust the weights according to the strength of the interference signals in each channel to meet the detection needs in different environments. By carefully managing the weights of the interference data and correction data of each channel, the performance of the multi-channel partial discharge monitoring equipment can be further optimized.

[0110] Reference Figure 5 , the method further comprises the following steps:

[0111] When the first channel is detecting, the frequency value of the second interference signal is extracted according to the second channel interference signal; the frequency value of the third interference signal is extracted according to the third channel interference signal; the ratio between the frequency value of the second interference signal and the frequency value of the third interference signal is calculated as the second calculated ratio. Among them, the method for extracting the frequency value of the second interference signal is as follows: the second channel interference signal obtained from the second channel is converted into a frequency domain signal using Fourier transform. In the frequency domain signal, the frequency components with higher energy are identified. Usually, the frequency component with the highest energy corresponds to the main frequency of the interference signal. The main frequency value of the second channel interference signal is recorded and recorded as f2. Similarly, the method for extracting the frequency value of the third interference signal is as follows: the third channel interference signal obtained from the third channel is also converted into a frequency domain signal using Fourier transform and other algorithms; in the frequency domain signal, the frequency component with the highest energy is identified. The main frequency value of the third channel interference signal is recorded and recorded as f3. The second calculated ratio = f2 / f3.

[0112] According to the second calculation ratio, the ratio between the weights of the second interference data and the second interference correction data is positively correlated and adjusted. The larger the second calculation ratio, the larger the ratio between the weights of the second interference data and the second interference correction data; the smaller the second calculation ratio, the smaller the ratio between the weights of the second interference data and the second interference correction data. That is, the larger the second calculation ratio, the stronger the interference signal of the second channel is in the frequency domain, so the second interference data and the second interference correction data are given a larger weight to more accurately reflect the actual situation of the second channel. High-frequency signals often contain more detailed information, but may also be more susceptible to noise or interference. Therefore, when processing high-frequency signals, it is necessary to increase the correction ratio to better suppress noise or interference, thereby retaining the detailed information of the signal. This can be achieved by adjusting the relevant parameters in the signal processing algorithm, such as increasing the filtering strength of the high-frequency band or adjusting the gain of the high-frequency band. In contrast, low-frequency signals usually contain less detailed information, but may contain more background information or low-frequency features. When processing low-frequency signals, due to their relatively low sensitivity to noise or interference, it is not necessary to significantly increase the correction ratio as high-frequency signals. On the contrary, a low correction ratio can be maintained to avoid excessive processing of low-frequency features.

[0113] The ratio between the weight of the second interference data and the weight of the second interference correction data=weight wD2 / weight wC2, and the initial value of the ratio is 1.

[0114] If the second calculated ratio = 2 (greater than 1):

[0115] Adjust the weight wD2 to 0.7 and the weight wC2 to 0.3.

[0116] At this time, weight wD2 / weight wC2>1.

[0117] If the second calculated ratio = 0.5 (less than 1):

[0118] Adjust the weight wD2 to 0.3 and the weight wC2 to 0.7.

[0119] At this time, weight wD2 / weight wC2<1. The specific adjustment value is obtained by looking up the table.

[0120] According to the second calculated ratio, the ratio between the weights of the third interference data and the third interference correction data is adjusted in an anti-correlation manner; the larger the second calculated ratio is, the smaller the ratio between the weights of the third interference data and the third interference correction data is; the smaller the second calculated ratio is, the larger the ratio between the weights of the third interference data and the third interference correction data is. That is, the larger the second calculated ratio is, the stronger the interference signal of the third channel is in the energy domain, but weaker in the frequency domain, and thus the third interference data and the third interference correction data are given smaller weights.

[0121] The ratio between the weights of the third interference data and the third interference correction data=weight wD3 / weight wC3, and the initial value of the ratio is 1.

[0122] If the second calculated ratio = 2 (greater than 1):

[0123] Adjust the weight wD3 to 0.3 and the weight wC3 to 0.7.

[0124] At this time, weight wD3 / weight wC3=0.3 / 0.7<1.

[0125] If the second calculated ratio = 0.5 (less than 1):

[0126] Adjust the weight wD3 to 0.7 and the weight wC3 to 0.3.

[0127] At this time, weight wD3 / weight wC3=0.7 / 0.3>1. The specific adjustment value is obtained by looking up the table.

[0128] By considering both the energy value and frequency characteristics of the interference signal, the interference situation of each channel can be more accurately evaluated, thereby improving the accuracy of detection. This method can flexibly adjust the weights according to the strength and frequency characteristics of the interference signal of each channel to meet the detection needs in different environments. By comprehensively considering the energy value and frequency characteristics, the performance of multi-channel partial discharge monitoring equipment can be more comprehensively optimized. A new step for adjusting the weights according to the ratio of the frequency values ​​of the interference signal has been added. Not only the energy value of the interference signal but also the frequency characteristics are considered, thereby more comprehensively evaluating the interference situation of each channel.

[0129] Reference Figure 6 , the method further comprises the following steps:

[0130] A first shielding coil is arranged around the first channel, a second shielding coil is arranged around the second channel, and a third shielding coil is arranged around the third channel; the first shielding coil, the second shielding coil and the third shielding coil are all in an open state. These shielding coils are in an open state by default, that is, grounded or maintaining a set voltage value to effectively shield external interference signals.

[0131] Based on the first channel start signal obtained, the first shielding coil is turned off, the second channel is started, and the second channel interference signal is obtained; the second channel is turned off, the third channel is started, and the third channel interference signal is obtained; the third channel is turned off; and the first shielding coil is started after the first partial discharge data is output.

[0132] When the first channel needs to perform detection work, the first shielding coil is first turned off. At this time, the first channel is in a non-shielding state to receive and detect partial discharge signals.

[0133] Then start the second channel, obtain its interference signal, and immediately turn off the second channel. The purpose of this step is to evaluate the potential interference of the second channel on the first channel.

[0134] Then start the third channel, obtain its interference signal, and turn off the third channel. The purpose of this step is to evaluate the potential interference of the third channel on the first channel.

[0135] After completing the acquisition of the interference signals of the second and third channels, the partial discharge data of the first channel is output, and the first shielding coil is reopened to prepare for the next detection work.

[0136] By setting and using shielding coils, mutual interference between channels can be effectively reduced, thereby improving the accuracy of detection. This method allows the shielding coil to be turned off when necessary to receive and detect partial discharge signals, and to be reopened after the detection is completed to shield the interference signal, thereby improving the flexibility of the method. By comprehensively considering the use of shielding coils and the interference between channels, the performance of multi-channel partial discharge monitoring equipment can be further optimized.

[0137] When the on state of the shielding coil is set to maintain the set voltage value, the step starts to execute the following steps:

[0138] The voltage value of the shielding coil of the corresponding channel is adjusted in a positive correlation with the energy value of the interference signal of the corresponding channel; the greater the energy value of the interference signal of the corresponding channel, the greater the voltage value of the shielding coil of the corresponding channel; the smaller the energy value of the interference signal of the corresponding channel, the smaller the voltage value of the shielding coil of the corresponding channel. This means that when the energy value of the interference signal of a certain channel is large, it means that the channel is subject to strong interference, so it is necessary to increase the voltage value of the corresponding shielding coil to enhance its shielding effect. On the contrary, when the energy value of the interference signal is small, the voltage value of the shielding coil can be reduced to avoid unnecessary energy consumption.

[0139] By dynamically adjusting the voltage value of the shielding coil according to the energy value of the interference signal, the mutual interference between channels can be more effectively reduced, thereby improving the accuracy of detection. When the interference signal is weak, by reducing the voltage value of the shielding coil, unnecessary energy consumption can be reduced and the energy efficiency of the equipment can be improved. This method allows the voltage value of the shielding coil to be dynamically adjusted according to the real-time interference situation, thereby enhancing the flexibility of the method.

[0140] In order to further improve the accuracy of detection, the method also includes the following steps:

[0141] There are multiple shielding coils corresponding to a channel; some shielding coils can be selectively enabled or disabled as needed.

[0142] The number of shielding coils of the corresponding channel is adjusted according to the positive correlation of the interference signal energy value of the corresponding channel; the greater the interference signal energy value of the corresponding channel, the greater the number of shielding coils of the corresponding channel; the smaller the interference signal energy value of the corresponding channel, the smaller the number of shielding coils of the corresponding channel. When the interference signal energy value of a certain channel is large, it means that the channel is subject to strong interference, so the number of corresponding shielding coils needs to be increased to enhance its shielding effect. On the contrary, when the interference signal energy value is small, the number of shielding coils can be reduced to reduce cost and complexity.

[0143] By increasing the number of shielding coils, the mutual interference between channels can be reduced more effectively, thereby improving the accuracy of detection. When the interference signal is weak, the cost and complexity of the equipment can be reduced by reducing the number of shielding coils. This method allows the number of shielding coils to be dynamically adjusted according to the real-time interference situation, thereby improving the flexibility of the method.

[0144] Among them, the shielding wires are arranged on the circuit board and around the channel; the shielding wires are selected in number through the transistor switch circuit, especially when they need to be connected to a voltage value set to maintain a set value.

[0145] An embodiment of the present application further discloses a multi-channel partial discharge signal detection system, comprising a processor, wherein the processor executes the steps of the multi-channel partial discharge signal detection method as described in any one of the above items.

[0146] An embodiment of the present application further discloses a storage medium, wherein a program is stored in the storage medium, and when the program is executed by a processor, the steps of any one of the above-mentioned methods for detecting multi-channel partial discharge signals are implemented.

[0147] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A method for detecting a multi-channel partial discharge signal, characterized in that: The steps include: Initializing the first channel, the second channel and the third channel, wherein the first channel, the second channel and the third channel are all in a closed state; Based on the acquired first channel start signal, start the second channel, acquire the second channel interference signal, close the second channel, start the third channel, acquire the third channel interference signal, and close the third channel; Based on the obtained first channel working signal, start the first channel to obtain a first detection signal; Based on the acquired first channel stop signal, the first channel is closed, and first partial discharge data is calculated based on the first detection signal; outputting the first partial discharge data; The second interference data is measured according to the second channel interference signal, and the third interference data is calculated according to the third channel interference signal; Matching second correction data according to the second interference data, and using the second correction data to correct the detection parameters of the second channel; matching third correction data according to the third interference data, and using the third correction data to correct the detection parameters of the third channel; After closing the first channel, restarting the second channel and the third channel to obtain a second channel interference correction signal and a third channel interference correction signal; The second interference correction data is calculated according to the second channel interference correction signal, and the third interference correction data is calculated according to the third channel interference correction signal; The second correction data is calculated by using a weighted average according to the second interference data and the second interference correction data, and the third correction data is calculated by using a weighted average according to the third interference data and the third interference correction data; When the second channel or the third channel is started according to the corresponding start signal, the first channel is started, the first channel interference signal is obtained, and the first channel is closed; First interference data is calculated and measured according to the interference signal of the first channel, first correction data is matched according to the first interference data, and the detection parameters of the first channel are corrected using the first correction data.

2. The method for detecting multi-channel partial discharge signals according to claim 1, characterized in that: The method further comprises the steps of: Extracting a first interference signal energy value according to the first channel interference signal, extracting a second interference signal energy value according to the second channel interference signal, and extracting a third interference signal energy value according to the third channel interference signal; Calculate the ratio of the first interference signal energy value, the second interference signal energy value and the third interference signal energy value as an energy ratio; The duration of the first channel detecting the interference signal is a first duration, the duration of the second channel detecting the interference signal is a second duration, and the duration of the third channel detecting the interference signal is a third duration; The sum of the first duration, the second duration and the third duration is a fixed acquisition time value; the first duration corresponds to the first interference signal energy value, the second duration corresponds to the second interference signal energy value, and the third duration corresponds to the third interference signal energy value; The values ​​of the first duration, the second duration and the third duration are adjusted according to the energy ratio.

3. The method for detecting multi-channel partial discharge signals according to claim 2, characterized in that: The method further comprises the steps of: When the first channel performs detection, the ratio between the energy value of the second interference signal and the energy value of the third interference signal is calculated as a first calculated ratio; positively correlate and adjust the ratio between the weights of the second interference data and the second interference correction data according to the first calculated ratio; The larger the first calculation ratio is, the larger the ratio between the weights of the second interference data and the second interference correction data is; The smaller the first calculation ratio is, the smaller the ratio between the weights of the second interference data and the second interference correction data is; According to the first calculated ratio, anti-correlation adjusts the ratio between the weights of the third interference data and the third interference correction data; The larger the first calculation ratio is, the smaller the ratio between the weights of the third interference data and the third interference correction data is; and the smaller the first calculation ratio is, the larger the ratio between the weights of the third interference data and the third interference correction data is.

4. The method for detecting multi-channel partial discharge signals according to claim 3, characterized in that: The method further comprises the steps of: When the first channel performs detection, a second interference signal frequency value is extracted according to the second channel interference signal, a third interference signal frequency value is extracted according to the third channel interference signal, and a ratio between the second interference signal frequency value and the third interference signal frequency value is calculated as a second calculated ratio; positively correlate and adjust the ratio between the weights of the second interference data and the second interference correction data according to the second calculated ratio; The larger the second calculation ratio is, the larger the ratio between the weights of the second interference data and the second interference correction data is; The smaller the second calculation ratio is, the smaller the ratio between the weights of the second interference data and the second interference correction data is; According to the second calculated ratio, anti-correlation adjusts the ratio between the weights of the third interference data and the third interference correction data; The larger the second calculation ratio is, the smaller the ratio between the weights of the third interference data and the third interference correction data is; and the smaller the second calculation ratio is, the larger the ratio between the weights of the third interference data and the third interference correction data is.

5. The method for detecting multi-channel partial discharge signals according to claim 1, characterized in that: The method further comprises the steps of: A first shielding coil is disposed next to the first channel, a second shielding coil is disposed next to the second channel, and a third shielding coil is disposed next to the third channel; the first shielding coil, the second shielding coil and the third shielding coil are all in an open state; Based on the acquired first channel start signal, turn off the first shielding coil, start the second channel, acquire the second channel interference signal, turn off the second channel, start the third channel, acquire the third channel interference signal, and turn off the third channel; After outputting the first partial discharge data, starting the first shielding coil; The open state is grounded or maintains the set voltage value.

6. The method for detecting multi-channel partial discharge signals according to claim 5, characterized in that: The method further comprises the steps of: If the on state is to maintain the set voltage value, the voltage value of the shielding coil of the corresponding channel is adjusted in positive correlation with the energy value of the interference signal of the corresponding channel; the greater the energy value of the interference signal of the corresponding channel, the greater the voltage value of the shielding coil of the corresponding channel; the smaller the energy value of the interference signal of the corresponding channel, the smaller the voltage value of the shielding coil of the corresponding channel.

7. The method for detecting multi-channel partial discharge signals according to claim 5, characterized in that: The method further comprises the steps of: There are multiple shielding coils corresponding to the channel; The number of shielding coils of the corresponding channel is adjusted in positive correlation with the energy value of the interference signal of the corresponding channel; the greater the energy value of the interference signal of the corresponding channel, the greater the number of shielding coils of the corresponding channel; the smaller the energy value of the interference signal of the corresponding channel, the smaller the number of shielding coils of the corresponding channel.

8. A multi-channel partial discharge signal detection system, characterized in that: The method comprises a processor, wherein the processor executes the steps of the multi-channel partial discharge signal detection method as claimed in any one of claims 1 to 7.

9. A storage medium, characterized in that: The medium stores a program, and when the program is executed by a processor, the steps of the multi-channel partial discharge signal detection method according to any one of claims 1 to 7 are implemented.

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