Interference filtering system for monitoring partial discharge signal of power equipment

Abstract

The invention discloses an interference filtering system for power equipment partial discharge signal monitoring, relates to the technical field of power equipment partial discharge monitoring, and effectively inhibits interference of interference signals on partial discharge signal detection. According to the method, the partial discharge signal of the power equipment is collected, Fourier transform is performed on the partial discharge signal to generate the corresponding partial discharge spectrum signal, the center frequency of the interference signal is extracted from the partial discharge spectrum data, and the suppression frequency point is established according to the center frequency of the interference signal. The method comprises the following steps of: generating real-time partial discharge spectrum data, extracting spectrum data of an interference signal from the real-time partial discharge spectrum data according to a suppression frequency point, further obtaining pure spectrum data, generating a partial discharge time domain signal according to the pure spectrum data, and further performing peak searching processing on the partial discharge time domain signal to obtain PRPS characteristic spectrogram data.

Description

Technical Field

[0001] The invention relates to the technical field of partial discharge monitoring of electric power equipment, in particular to an interference filtering system for partial discharge signal monitoring of electric power equipment. Background Art

[0002] With the rapid development of my country's economic construction and the gradual improvement of people's living standards, the safety and reliability of power grid operation are becoming increasingly important. As one of the core components of power transmission, the operating status of cables will directly affect the stable operation of the power grid. However, during production, transportation, storage, installation and operation, certain accidental factors may cause defects in the insulation system and may further develop into equipment failures. Partial discharge (PD) is the main cause of cable insulation failure and can also be used as a means to assess the degree of insulation degradation. Carrying out PD online monitoring of cables and obtaining PD information will help to understand their insulation status and provide strong support for the formulation of maintenance and operation strategies.

[0003] Among the many partial discharge detection methods, high frequency current method (HFCT) is an effective detection method, but this method is easily affected by on-site interference, most of which is single-frequency interference. This interference has a great impact on partial discharge detection. When it occurs, it often drowns out normal partial discharge signals. In order to suppress interference signals, improve the signal-to-noise ratio of the system, and reduce the false alarm rate, an interference filtering system for partial discharge signal monitoring of power equipment is provided. Summary of the invention

[0004] In order to solve the above technical problems, the object of the present invention is to provide an interference filtering system for monitoring partial discharge signals of power equipment.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: An interference filtering system for monitoring partial discharge signals of power equipment comprises a cloud computing platform, wherein the cloud computing platform is communicatively connected with a signal acquisition module, an interference suppression module, a Fourier transform module and a signal extraction module; The signal acquisition module is used to collect partial discharge signals of power equipment; The Fourier transform module is used to perform weighted processing on the partial discharge signal, and perform Fourier transform on the weighted partial discharge signal to obtain a corresponding partial discharge spectrum signal, and convert the spectrum data of the interference signal from the interference suppression module into the corresponding partial discharge spectrum data; The interference suppression module is provided with a DDR storage unit and a signal suppression unit; The DDR storage unit is used to extract the center frequency of the interference signal from the partial discharge spectrum data from the Fourier transform module, and send the extraction result to the signal suppression unit; The signal suppression unit is used to establish a suppression frequency point according to the center frequency of the interference signal, and then extract the spectrum data of the interference signal from the real-time partial discharge spectrum data according to the suppression frequency point, and send the extraction result to the Fourier transform module; The signal extraction module is used to perform peak-finding processing on the partial discharge time domain signal, thereby obtaining PRPS characteristic spectrum data.

[0006] Furthermore, the partial discharge signal acquisition process includes: Signal acquisition module: Each power equipment in the power grid is respectively provided with three groups of signal acquisition devices, and the signal acquisition devices of each power equipment are numbered; When any power equipment in the power grid is running, the cloud computing platform sends a signal acquisition instruction to the signal acquisition module; The signal acquisition module sends the signal acquisition instruction to the three groups of signal acquisition devices of the corresponding power equipment at the same time. Then, when the power equipment has a fault point or the electric field strength at the location is too high, the power equipment generates a partial discharge signal, and then each group of signal acquisition devices collects the partial discharge signal. Furthermore, the process of performing weighted processing on the partial discharge signal includes: The Fourier transform module is provided with a window function node for optimizing and adjusting the partial discharge signal from the signal acquisition module; A rectangular coordinate system is established. When the Fourier transform module receives the partial discharge signal, the partial discharge signal is mapped onto the rectangular coordinate system in real time. The unit time length is set, and the partial discharge signal is divided into a plurality of partial discharge sub-signals according to the unit time length. The part of the partial discharge signal that is less than the unit time length is not divided temporarily. When the cumulative time length of the partial discharge signal subsequently sent by the signal acquisition module and the undivided part is equal to the unit time length, it is divided; A window function is established, and the local signal at each time node is multiplied with the corresponding window function sequence in sequence to obtain a weighted local discharge signal.

[0007] Furthermore, the process of performing Fourier transform on the weighted partial discharge signal includes: The amplitude value and power value of each frequency domain component on the partial discharge frequency domain signal are obtained, and each amplitude value and power value are sequentially spliced ​​according to the position of the corresponding frequency domain component on the partial discharge frequency domain signal, so as to obtain the corresponding partial discharge amplitude spectrum and partial discharge power spectrum; After normalizing the partial discharge amplitude spectrum and the partial discharge power spectrum, the partial discharge amplitude spectrum and the partial discharge power spectrum are overlapped and mapped according to the time nodes corresponding to the amplitude values ​​and power values ​​in the two, so as to obtain the partial discharge spectrum data.

[0008] Furthermore, the process of extracting the center frequency of the interference signal from the partial discharge spectrum data includes: The interference suppression module sends the partial discharge spectrum data to the DDR storage unit and the signal suppression unit respectively; Since the positions of the signal acquisition devices for acquiring partial discharge signals relative to the power equipment are different, the interference signals contained in the partial discharge signals acquired by the three groups of signal acquisition devices are not completely the same; As a result, the partial discharge spectrum data generated by the corresponding processing of the partial discharge signals collected by the three groups of signal acquisition devices are somewhat different; A rectangular coordinate system is established, and after passing three groups of partial discharge spectrum data of the same power equipment through a filter, a plurality of partial discharge spectrum sub-data are separated, and each partial discharge spectrum sub-data is marked with the serial number of the corresponding signal acquisition device, and then the partial discharge spectrum sub-data corresponding to the three groups of partial discharge spectrum data are simultaneously mapped on a rectangular coordinate system; Matching the partial discharge spectrum sub-data with different numbers with each other, if any two partial discharge spectrum sub-data with different numbers are the same, then the two are judged to be matched, otherwise, the two are judged to be mismatched; Since the partial discharge signals collected by the three groups of signal acquisition devices are the same, the partial discharge spectrum sub-data corresponding to the partial discharge signals with different numbers must have a matching relationship. For the interference signals in the partial discharge signals collected by different signal acquisition devices, the corresponding partial discharge spectrum sub-data do not have a matching relationship. Count the matching results of each partial discharge spectrum sub-data, remove the matching results with three numbers, and keep the matching results without three numbers; splicing the partial discharge spectrum sub-data with the same number in the retained matching results, thereby obtaining the spectrum data of the interference signal collected by the corresponding signal collection device; Set the peak threshold to mark the locations where the peak value in the spectrum data of the interference signal is greater than or equal to the peak threshold, and automatically ignore the locations where the peak value is less than the peak threshold; The weighted average of the peak values ​​with marked positions is obtained, and then the center frequency of the corresponding interference signal is obtained. The above operation is repeated to obtain the center frequency of the interference signal in each partial discharge signal.

[0009] Furthermore, the process of generating clean spectrum data includes: The DDR memory unit sends the center frequency of each interference signal to the interference suppression module, and then the interference suppression module sets the corresponding suppression frequency point according to the center frequency of each interference signal; The suppression frequency point is used to extract the spectrum data of the corresponding interference signal from the partial discharge spectrum data from the Fourier transform module. The interference suppression module extends the data transmission channel between it and the Fourier transform module to the signal suppression unit, and sets the corresponding suppression frequency point in the data transmission channel; When the Fourier transform module sends the partial discharge spectrum data to the signal suppression unit through the data transmission channel, the suppression frequency point set in the data transmission channel eliminates the spectrum data of the frequency corresponding to the partial discharge spectrum data to obtain spectrum data that does not contain the interference signal part, which is recorded as pure spectrum data.

[0010] Furthermore, the process of generating a local time domain signal according to the clean spectrum data includes: Whenever the signal suppression unit filters out pure spectrum data of unit time length, the pure spectrum data is sent to the Fourier transform module through the data transmission channel; The Fourier transform module copies the pure spectrum data, and splices the copied pure spectrum data with the original pure spectrum data to obtain complete pure spectrum data; According to the time sequence of the complete clean spectrum data, the complete clean spectrum data is reversed, and an IFFT operation is performed on the reversed complete clean spectrum data to obtain the corresponding local time domain signal.

[0011] Furthermore, the process of performing peak search processing on the local party time domain signal includes: The signal extraction module obtains the first-order derivative of the local time domain signal and sets a derivative value threshold. If the derivative value at the corresponding time node is greater than or equal to the derivative value threshold, the peak value at the corresponding time node is recorded as the target peak value. If the derivative value at the corresponding time node is greater than or equal to the derivative value threshold, the peak value at the time node is ignored. The target peak is integrated to obtain the PRPS characteristic spectrum data of the corresponding local time domain signal.

[0012] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention collects local discharge signals of power equipment, generates corresponding local discharge spectrum signals after Fourier transform of the local discharge signals, extracts the center frequency of the interference signal from the local discharge spectrum data, establishes a suppression frequency point according to the center frequency of the interference signal, and then extracts the spectrum data of the interference signal from the real-time partial discharge spectrum data according to the suppression frequency point, thereby realizing the real-time suppression function of multiple frequency interference signals to a certain extent.

[0013] 2. The present invention generates a partial discharge time domain signal based on pure spectrum data, and then performs peak-finding processing on the partial discharge time domain signal to obtain PRPS characteristic spectrum data, thereby effectively improving the signal-to-noise ratio of the partial discharge signal and reducing the false alarm rate of power equipment detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention.

[0015] Figure 1 It is a schematic diagram of the present invention. DETAILED DESCRIPTION

[0016] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0017] like Figure 1 As shown, an interference filtering system for partial discharge signal monitoring of power equipment includes a cloud computing platform, and the cloud computing platform is communicatively connected with a signal acquisition module, an interference suppression module, a Fourier transform module, and a signal extraction module; The signal acquisition module is used to collect partial discharge signals of power equipment; The Fourier transform module is used to perform weighted processing on the partial discharge signal, and perform Fourier transform on the weighted partial discharge signal to obtain a corresponding partial discharge spectrum signal, and convert the spectrum data of the interference signal from the interference suppression module into the corresponding partial discharge spectrum data; The interference suppression module is provided with a DDR storage unit and a signal suppression unit; The DDR storage unit is used to extract the center frequency of the interference signal from the partial discharge spectrum data from the Fourier transform module, and send the extraction result to the signal suppression unit; The signal suppression unit is used to establish a suppression frequency point according to the center frequency of the interference signal, and then extract the spectrum data of the interference signal from the real-time partial discharge spectrum data according to the suppression frequency point, and send the extraction result to the Fourier transform module; The signal extraction module is used to perform peak-finding processing on the partial discharge time domain signal, thereby obtaining PRPS characteristic spectrum data.

[0018] Further, the working principle of the present invention is described below by way of examples: Signal acquisition module Each power equipment in the power grid is equipped with three groups of signal acquisition devices, and each power equipment is numbered, where the number can be s1, s2, ..., s n , where n is a natural number greater than 0, and n represents the total number of power devices in the power grid; It should be noted that the power equipment in the power grid includes generators, cables, etc., and the positions of the three groups of signal acquisition devices relative to the power equipment are different; Then the signal acquisition module sets a number s for the signal acquisition device of each power equipment according to the number of the power equipment. 1，1 、s 1,2 ,……,s n，3 , where s n，3 Indicates the number is s n The third group of signal acquisition devices for power equipment; When any power equipment in the power grid is running, the cloud computing platform sends a signal collection instruction to the signal collection module according to the number of the corresponding power equipment; The signal acquisition module sends the signal acquisition instruction to the three groups of signal acquisition devices of the corresponding power equipment at the same time, and then when the power equipment has a fault point or the electric field strength at the location is too high, the power equipment generates a partial discharge signal; Each group of signal acquisition devices acquires partial discharge signals and sends them to the signal acquisition device. Then, after the signal acquisition module marks each partial discharge signal with the number of the corresponding signal acquisition device, the partial discharge signal is sent to the Fourier transform module in real time.

[0019] Furthermore, the Fourier transform module is provided with a window function node for optimizing and adjusting the partial discharge signal from the signal acquisition module, and a data transmission channel with a bandwidth of N is provided between the Fourier transform module and the signal acquisition module; The process of optimizing and adjusting the local release point signal according to the window function node includes: A rectangular coordinate system is established. When the Fourier transform module receives the partial discharge signal, the partial discharge signal is mapped onto the rectangular coordinate system in real time. The unit time length is set, and the partial discharge signal is divided into a plurality of partial discharge sub-signals according to the unit time length. The part of the partial discharge signal that is less than the unit time length is not divided temporarily. When the cumulative time length of the partial discharge signal subsequently sent by the signal acquisition module and the undivided part is equal to the unit time length, it is divided; It should be noted that the unit time length represents the length of the partial discharge signal collected by the signal collection device within a unit time; A window function is established, and the expression of the window function is: ; Where W(n) represents the window function sequence at the nth time node, and n represents each time node on the partial discharge signal; The local signal at each time node is multiplied with the corresponding window function sequence in turn to obtain a weighted local discharge signal.

[0020] Further, the Fourier transform module performs Fourier transform on the weighted partial discharge signal, and converts the partial discharge signal into a partial discharge frequency domain signal according to the Fourier transform result; The amplitude value and power value of each frequency domain component on the partial discharge frequency domain signal are obtained, and each amplitude value and power value are sequentially spliced ​​according to the position of the corresponding frequency domain component on the partial discharge frequency domain signal, so as to obtain the corresponding partial discharge amplitude spectrum and partial discharge power spectrum; After normalizing the partial discharge amplitude spectrum and the partial discharge power spectrum, the partial discharge amplitude spectrum and the partial discharge power spectrum are overlapped and mapped according to the time nodes corresponding to the amplitude values ​​and power values ​​in the two, so as to obtain the partial discharge spectrum data.

[0021] Further, the Fourier transform module sends the partial discharge spectrum signal to the interference suppression module, and then the interference suppression module sends the partial discharge spectrum data to the DDR storage unit and the signal suppression unit respectively; Since the positions of the signal acquisition devices for collecting partial discharge signals relative to the power equipment are different, but the partial discharge signals released by the power equipment are consistent, and since the positions of the three groups of signal acquisition devices are different, the interference signals contained in the partial discharge signals collected by the three groups of signal acquisition devices are not completely the same; As a result, the partial discharge spectrum data generated by the corresponding processing of the partial discharge signals collected by the three groups of signal acquisition devices are somewhat different; A rectangular coordinate system is established, and after passing three groups of partial discharge spectrum data of the same power equipment through a filter, a plurality of partial discharge spectrum sub-data are separated, and each partial discharge spectrum sub-data is marked with the serial number of the corresponding signal acquisition device, and then the partial discharge spectrum sub-data corresponding to the three groups of partial discharge spectrum data are simultaneously mapped on a rectangular coordinate system; Matching the partial discharge spectrum sub-data with different numbers with each other, if any two partial discharge spectrum sub-data with different numbers are the same, then the two are judged to be matched, otherwise, the two are judged to be mismatched; Since the partial discharge signals collected by the three groups of signal acquisition devices are the same, the partial discharge spectrum sub-data corresponding to the partial discharge signals with different numbers must have a matching relationship. For the interference signals in the partial discharge signals collected by different signal acquisition devices, the corresponding partial discharge spectrum sub-data do not have a matching relationship. Count the matching results of each partial discharge spectrum sub-data, remove the matching results with three numbers, and keep the matching results without three numbers; splicing the partial discharge spectrum sub-data with the same number in the retained matching results, thereby obtaining the spectrum data of the interference signal collected by the corresponding signal collection device; Set the peak threshold to mark the locations where the peak value in the spectrum data of the interference signal is greater than or equal to the peak threshold, and automatically ignore the locations where the peak value is less than the peak threshold; Calculate the weighted average of the peaks with marked positions to obtain the center frequency of the corresponding interference signal; The above operation is repeated to obtain the center frequency of the interference signal in each partial discharge signal. Further, the DDR memory unit sends the center frequency of each interference signal to the interference suppression module; Then the interference suppression module sets the corresponding suppression frequency point according to the center frequency of each interference signal; The suppressed frequency point is used to extract the spectrum data of the corresponding interference signal from the partial discharge spectrum data from the Fourier transform module; Then the interference suppression module extends the data transmission channel between it and the Fourier transform module to the signal suppression unit, and sets the corresponding suppression frequency point in the data transmission channel; When the Fourier transform module sends the partial discharge spectrum data to the signal suppression unit through the data transmission channel, the suppression frequency point set in the data transmission channel eliminates the spectrum data of the frequency corresponding to the partial discharge spectrum data, thereby obtaining the spectrum data that does not contain the interference signal part, which is recorded as pure spectrum data.

[0022] Furthermore, whenever the signal suppression unit filters out pure spectrum data of unit time length, the pure spectrum data is sent to the Fourier transform module through the data transmission channel; The Fourier transform module copies the pure spectrum data, and splices the copied pure spectrum data with the original pure spectrum data to obtain complete pure spectrum data; According to the time sequence of the complete clean spectrum data, the complete clean spectrum data is reversed, and an IFFT operation is performed on the reversed complete clean spectrum data to obtain the corresponding local time domain signal; The Fourier transform module sends the local time domain signal to the signal extraction module.

[0023] Furthermore, the signal extraction module obtains the first-order derivative of the local time domain signal and sets a derivative value threshold; If the derivative value at the corresponding time node is greater than or equal to the derivative value threshold, the peak value at the corresponding time node is recorded as the target peak value; If the derivative value at the corresponding time node is greater than or equal to the derivative value threshold, the peak value at the time node is ignored; The target peak is integrated to obtain the PRPS characteristic spectrum data of the corresponding local time domain signal.

[0024] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. An interference filtering system for monitoring partial discharge signals of power equipment, comprising a cloud computing platform, characterized in that: The cloud computing platform is communicatively connected with a signal acquisition module, an interference suppression module, a Fourier transform module and a signal extraction module; The signal acquisition module is used to collect partial discharge signals of power equipment; The Fourier transform module is used to perform weighted processing on the partial discharge signal, and perform Fourier transform on the weighted partial discharge signal to obtain a corresponding partial discharge spectrum signal, and convert the spectrum data of the interference signal from the interference suppression module into the corresponding partial discharge spectrum data; The interference suppression module is provided with a DDR storage unit and a signal suppression unit; The DDR storage unit is used to extract the center frequency of the interference signal from the partial discharge spectrum data from the Fourier transform module, and send the extraction result to the signal suppression unit; The signal suppression unit is used to establish a suppression frequency point according to the center frequency of the interference signal, and then extract the spectrum data of the interference signal from the real-time partial discharge spectrum data according to the suppression frequency point, and send the extraction result to the Fourier transform module; The signal extraction module is used to perform peak-finding processing on the partial discharge time domain signal, thereby obtaining PRPS characteristic spectrum data.

2. The interference filtering system for monitoring partial discharge signals of power equipment according to claim 1, characterized in that: The acquisition process of partial discharge signals includes: Signal acquisition module: Each power equipment in the power grid is respectively provided with three groups of signal acquisition devices, and the signal acquisition devices of each power equipment are numbered; When any power equipment in the power grid is running, the cloud computing platform sends a signal acquisition instruction to the signal acquisition module; The signal acquisition module sends the signal acquisition instructions to the three groups of signal acquisition devices of the corresponding power equipment at the same time. When a fault point occurs in the power equipment or the electric field strength at the location is too high, the power equipment generates a local discharge signal, and then each group of signal acquisition devices collects the local discharge signal.

3. The interference filtering system for monitoring partial discharge signals of power equipment according to claim 2, characterized in that: The process of weighting the partial discharge signal includes: The Fourier transform module is provided with a window function node for optimizing and adjusting the partial discharge signal from the signal acquisition module; A rectangular coordinate system is established. When the Fourier transform module receives the partial discharge signal, the partial discharge signal is mapped onto the rectangular coordinate system in real time. The unit time length is set, and the partial discharge signal is divided into a plurality of partial discharge sub-signals according to the unit time length. The part of the partial discharge signal that is less than the unit time length is not divided temporarily. When the cumulative time length of the partial discharge signal subsequently sent by the signal acquisition module and the undivided part is equal to the unit time length, it is divided; A window function is established, and the local signal at each time node is multiplied with the corresponding window function sequence in sequence to obtain a weighted local discharge signal.

4. The interference filtering system for monitoring partial discharge signals of power equipment according to claim 3, characterized in that: The process of Fourier transforming the weighted partial discharge signal includes: The amplitude value and power value of each frequency domain component on the partial discharge frequency domain signal are obtained, and each amplitude value and power value are sequentially spliced ​​according to the position of the corresponding frequency domain component on the partial discharge frequency domain signal, so as to obtain the corresponding partial discharge amplitude spectrum and partial discharge power spectrum; After normalizing the partial discharge amplitude spectrum and the partial discharge power spectrum, the partial discharge amplitude spectrum and the partial discharge power spectrum are overlapped and mapped according to the time nodes corresponding to the amplitude values ​​and power values ​​in the two, so as to obtain the partial discharge spectrum data.

5. The interference filtering system for monitoring partial discharge signals of power equipment according to claim 4, characterized in that: The process of extracting the center frequency of the interference signal from the partial discharge spectrum data includes: The interference suppression module sends the partial discharge spectrum data to the DDR storage unit and the signal suppression unit respectively; Since the positions of the signal acquisition devices for acquiring partial discharge signals relative to the power equipment are different, the interference signals contained in the partial discharge signals acquired by the three groups of signal acquisition devices are not completely the same; As a result, the partial discharge spectrum data generated by the corresponding processing of the partial discharge signals collected by the three groups of signal acquisition devices are somewhat different; A rectangular coordinate system is established, and after passing three groups of partial discharge spectrum data of the same power equipment through a filter, a plurality of partial discharge spectrum sub-data are separated, and each partial discharge spectrum sub-data is marked with the serial number of the corresponding signal acquisition device, and then the partial discharge spectrum sub-data corresponding to the three groups of partial discharge spectrum data are simultaneously mapped on a rectangular coordinate system; Matching the partial discharge spectrum sub-data with different numbers with each other, if any two partial discharge spectrum sub-data with different numbers are the same, then the two are judged to be matched, otherwise, the two are judged to be mismatched; Since the partial discharge signals collected by the three groups of signal acquisition devices are the same, the partial discharge spectrum sub-data corresponding to the partial discharge signals with different numbers must have a matching relationship. For the interference signals in the partial discharge signals collected by different signal acquisition devices, the corresponding partial discharge spectrum sub-data do not have a matching relationship. Count the matching results of each partial discharge spectrum sub-data, remove the matching results with three numbers, and keep the matching results without three numbers; splicing the partial discharge spectrum sub-data with the same number in the retained matching results, thereby obtaining the spectrum data of the interference signal collected by the corresponding signal collection device; Set the peak threshold to mark the locations where the peak value in the spectrum data of the interference signal is greater than or equal to the peak threshold, and automatically ignore the locations where the peak value is less than the peak threshold; The weighted average of the peak values ​​with marked positions is obtained, and then the center frequency of the corresponding interference signal is obtained, and then the center frequency of the interference signal in each partial discharge signal is obtained.

6. The interference filtering system for monitoring partial discharge signals of power equipment according to claim 5, characterized in that: The process of generating clean spectrum data includes: The DDR memory unit sends the center frequency of each interference signal to the interference suppression module, and then the interference suppression module sets the corresponding suppression frequency point according to the center frequency of each interference signal; The suppression frequency point is used to extract the spectrum data of the corresponding interference signal from the partial discharge spectrum data from the Fourier transform module. The interference suppression module extends the data transmission channel between it and the Fourier transform module to the signal suppression unit, and sets the corresponding suppression frequency point in the data transmission channel; When the Fourier transform module sends the partial discharge spectrum data to the signal suppression unit through the data transmission channel, the suppression frequency point set in the data transmission channel eliminates the spectrum data of the frequency corresponding to the partial discharge spectrum data to obtain spectrum data that does not contain the interference signal part, which is recorded as pure spectrum data.

7. The interference filtering system for monitoring partial discharge signals of power equipment according to claim 6, characterized in that: The process of generating a local time domain signal according to the clean spectrum data includes: Whenever the signal suppression unit filters out pure spectrum data of unit time length, the pure spectrum data is sent to the Fourier transform module through the data transmission channel; The Fourier transform module copies the pure spectrum data, and splices the copied pure spectrum data with the original pure spectrum data to obtain complete pure spectrum data; According to the time sequence of the complete clean spectrum data, the complete clean spectrum data is reversed, and an IFFT operation is performed on the reversed complete clean spectrum data to obtain the corresponding local time domain signal.

8. The interference filtering system for monitoring partial discharge signals of power equipment according to claim 7, characterized in that: The process of performing peak search processing on the local time domain signal includes: The signal extraction module obtains the first-order derivative of the local time domain signal and sets a derivative value threshold. If the derivative value at the corresponding time node is greater than or equal to the derivative value threshold, the peak value at the corresponding time node is recorded as the target peak value. If the derivative value at the corresponding time node is greater than or equal to the derivative value threshold, the peak value at the time node is ignored. The target peak is integrated to obtain the PRPS characteristic spectrum data of the corresponding local time domain signal.

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