A high-precision porcelain insulator zero-value electrification detection method and device

Abstract

This invention provides a high-precision method and apparatus for detecting zero-value live defects in porcelain insulators, belonging to the field of power equipment testing. The apparatus includes a main unit and a handheld terminal; the main unit comprises a high-voltage pulse generator, test electrodes, a pulse current sensor, a data acquisition unit, and a communication unit, and can be mounted on a drone, robot, or insulating pole; the handheld terminal includes wireless communication, data processing, intelligent diagnostics, and human-machine interaction units. The method includes: bringing the test electrodes into contact with the live insulator via a work platform; applying a high-voltage pulse excitation; acquiring voltage and current signals and transmitting them to the handheld terminal; filtering out power frequency interference; performing joint diagnostics based on insulation resistance calculation and discharge signal identification, and outputting the insulator status. This invention achieves high-precision, safe, and reliable detection of zero-value defects in porcelain insulators under uninterrupted power supply conditions.

Description

Technical Field

[0001] This invention relates to the field of zero-value detection of porcelain insulators, specifically a high-precision method and device for zero-value live detection of porcelain insulators. Background Technology

[0002] Disc suspension porcelain insulators are widely used due to their outstanding advantages such as high mechanical strength, long service life, and good plasticity. They cannot be replaced by composite or glass insulators in many fields. In particular, large-tonnage porcelain insulators of 420kN and above are indispensable in the ultra-high voltage field. However, the zero-value problem is a key factor restricting the application and development of porcelain insulators. In addition, the difficulty of power outages and the short time window for power outage maintenance are common objective factors. Therefore, there is a particular lack of accurate zero-value live detection technology for porcelain insulators.

[0003] Currently, methods for detecting zero values ​​in porcelain insulators include the insulator resistance method, power frequency withstand voltage method, high-voltage pulse method, spark gap method, distributed voltage method, and infrared detection method. Among these, the high-voltage pulse method is highly accurate and convenient, but it requires operation under power outage conditions. The spark gap method, distributed voltage method, and infrared detection method, which are used for detecting zero values ​​while the insulator is live, cannot guarantee completely accurate measurement results and cannot definitively determine whether a suspected zero-value porcelain insulator actually has a zero-value problem, thus making it impossible to provide a targeted and scientific solution. Summary of the Invention

[0004] This invention provides a high-precision method and device for detecting zero-value energized porcelain insulators. It can output pulsed high voltage of 35kV or above, avoid strong electromagnetic interference, prevent external high voltage from causing overcurrent in the test circuit, effectively filter out power frequency information, and accurately diagnose zero-value insulators. Relying on operating platforms such as drones, robots, and insulating rods, it can accurately detect the zero value of porcelain insulators under energized operating conditions.

[0005] A high-precision zero-value live detection device for porcelain insulators includes a main unit and a handheld terminal;

[0006] The host includes:

[0007] A pulse high voltage generator is used to generate and output high voltage pulses and apply them to the insulator under test.

[0008] Test electrodes are used to make electrical contact with both ends of the energized porcelain insulator under test.

[0009] A pulse current sensor is used to measure the current signal flowing through the insulator under test under the excitation of the high voltage pulse.

[0010] The data acquisition unit is used to acquire the voltage signal across the insulator under test and the current signal measured by the pulse current sensor, and perform analog-to-digital conversion to obtain a digital signal sequence.

[0011] The communication unit is used to transmit signals to the outside world, receive control signals from the handheld terminal, and send digital signal sequences converted from analog to digital by the data acquisition unit.

[0012] A power module is used to supply power to the host computer;

[0013] A work platform for mounting the host computer, the work platform including a drone, a robot or an insulating pole;

[0014] The handheld terminal includes:

[0015] The wireless communication unit is used to establish a communication connection with the communication unit of the host, output control signals, and receive signals from the host.

[0016] The data processing unit is used to process the received signals to eliminate power frequency interference;

[0017] The intelligent diagnostic unit is used to diagnose the condition of the insulator under test by analyzing the insulation resistance value and high-voltage pulse discharge characteristics based on the processed signal.

[0018] The human-computer interaction unit is used for parameter setting and result display.

[0019] Furthermore, the host also includes a protection resistor, which includes a first resistor connected in series between the high-voltage end of the test electrode and the pulse high-voltage generator, and a second resistor connected in series between the low-voltage end of the test electrode and ground, for limiting the current introduced by the external high voltage.

[0020] Furthermore, the data acquisition unit includes an electromagnetic shielding shell and a high-resolution ADC module disposed within the electromagnetic shielding shell, the electromagnetic shielding shell being provided with a radio frequency shielding interface.

[0021] Furthermore, the test electrode includes a detachable magnetic elastic electrode, a spiral electrode support rod for connecting and adjusting the electrode, a universal connecting flange, and a wire connecting rod, which is connected to the high-voltage pulse generator potting box.

[0022] Furthermore, the intelligent diagnostic unit is configured to execute the following diagnostic logic: identify the discharge signal under the action of the high-voltage pulse and calculate the insulation resistance value of the insulator under test; perform joint diagnosis based on the logical relationship between the identification result of the discharge signal and the insulation resistance value.

[0023] Furthermore, the intelligent diagnostic unit is also configured to compare the data of the currently tested insulator with the data of other insulators in the same string using a big data model to assist in diagnosis.

[0024] Furthermore, the high-resolution ADC module has a sampling rate of ≥100MS / s and a resolution of ≥14 bits.

[0025] Furthermore, the test electrode also includes a contact state detection module, which is used to detect the contact resistance or contact pressure between the electrode and the insulator under test in real time during the contact step, and to feed back the contact state to the handheld terminal.

[0026] Furthermore, the host also includes an overcurrent protection module, which automatically cuts off the pulse high voltage output and reports the fault information to the handheld terminal when the detected current exceeds a set threshold.

[0027] A high-precision method for zero-value live detection of porcelain insulators, using the device described above, includes the following steps:

[0028] Contact step: The test electrode is reliably contacted with both ends of the porcelain insulator under test by using the working platform equipped with the host computer;

[0029] Excitation step: The handheld terminal is used to set and trigger the high-voltage pulse generator to apply a high-voltage pulse to the insulator under test;

[0030] Data Acquisition and Transmission Steps: The host computer's data acquisition unit acquires the voltage signal and current signal flowing through the two ends of the insulator under test during the application of the high-voltage pulse, and transmits the converted digital signal sequence to the handheld terminal through the communication unit.

[0031] Filtering step: In the handheld terminal, a filtering algorithm is used to process the received digital signal sequence to filter out the power frequency interference signal and obtain the filtered pulse response signal;

[0032] Diagnostic steps: Based on the filtered pulse response signal, calculate the insulation resistance value of the insulator under test, and identify whether a discharge signal is generated under the action of the high voltage pulse; combine the insulation resistance value and the identification result of the discharge signal to diagnose the state of the insulator under test.

[0033] Furthermore, the filtering step specifically involves: employing a band-stop filtering algorithm to calculate the signal difference before and after applying the pulsed high voltage, thereby eliminating the power frequency periodic component in the signal.

[0034] Furthermore, the diagnostic steps specifically include:

[0035] If a discharge signal is detected, the insulator is diagnosed as having a zero value.

[0036] If no discharge signal is detected, then determine the calculated insulation resistance value:

[0037] If the insulation resistance value is lower than the zero-value insulator resistance threshold, it is diagnosed as zero.

[0038] If the insulation resistance value is higher than the high resistance threshold, it is diagnosed as a high value.

[0039] If the insulation resistance value is between the zero-value insulator resistance threshold and the high-value resistance threshold, and the voltage waveform does not discharge, it is judged to be a high value.

[0040] Furthermore, the contact step also includes: monitoring the contact quality in real time through the contact state detection module of the test electrode; if the contact resistance exceeds the set range, issuing an adjustment prompt or interrupting the test.

[0041] Furthermore, the band-stop filtering algorithm used in the filtering step also includes an adaptive power frequency tracking function, which dynamically adjusts the filtering parameters according to the actual power grid frequency.

[0042] Furthermore, the diagnostic steps also include: combining historical test data and environmental parameters of each insulator in the same insulator string, and using a machine learning model to assess and correct the confidence level of the current diagnostic results.

[0043] This invention addresses the shortcomings of traditional zero-value live-line detection methods for porcelain insulators by proposing a high-precision zero-value live-line detection device and method based on pulsed high voltage. This device fully leverages the convenience and high accuracy advantages of the high-voltage pulse method. Through electromagnetic shielding and protective resistor design, it achieves contact measurement under high-voltage live-line conditions, avoiding interference from strong electromagnetic fields and overcurrent effects from external high voltage in the test circuit. A filtering algorithm effectively filters out interference from power frequency voltage and current. Furthermore, by employing a discharge signal identification algorithm under pulsed high voltage and an insulation resistance value calculation method, a joint diagnostic criterion of insulation resistance and pulsed high-voltage discharge signal is proposed, avoiding the inaccuracy problem caused by a single insulation resistance value criterion. Attached Figure Description

[0044] Figure 1 This is a schematic diagram of the main unit in the high-precision porcelain insulator zero-value live detection device of the present invention;

[0045] Figure 2 This is a schematic diagram of the handheld terminal in the high-precision porcelain insulator zero-value live detection device of the present invention;

[0046] Figure 3 This is a schematic diagram of the structure of the test electrode in this invention;

[0047] Figure 4 This is a flowchart of the high-precision zero-value live detection method for porcelain insulators according to the present invention;

[0048] Figure 5This is a flowchart of the power frequency signal rejection algorithm of the present invention:

[0049] Figure 6 It is the response signal of a normal insulator before filtering under pulse excitation;

[0050] Figure 7 It is the filtered response signal after normal insulator pulse excitation;

[0051] Figure 8 It is the response signal of a zero-value insulator before filtering under pulse excitation;

[0052] Figure 9 It is the filtered response signal after pulse excitation of a zero-value insulator;

[0053] Figure 10 This is a diagnostic logic block diagram for zero-value porcelain insulators.

[0054] The reference numerals in the figure are described below:

[0055] 1. Pulse high voltage generator; 2. Pulse current sensor; 3. Protective current limiting resistor; 4. Test electrode; 5. Data acquisition unit; 6. Communication unit; 7. Microprocessor; 8. Power supply module; 9. Working platform;

[0056] 10. Wireless communication unit; 11. Data processing unit; 12. Intelligent diagnostic unit; 13. Human-computer interaction unit;

[0057] 101. Detachable magnetic elastic electrode; 102. Spiral electrode support rod; 103. Universal connecting flange; 104. Threading connecting rod; 105. High voltage pulse generator potting box; 106. UAV mounting flange; 107. Insulator testing equipment; 108. Communication box; 109. Connecting operating rod flange. Detailed Implementation

[0058] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0059] Please see Figure 1-3 This invention provides a high-precision zero-value live detection device for porcelain insulators, including a main unit and a handheld terminal.

[0060] The host includes a pulse high voltage generator 1, a pulse current sensor 2, a protective resistor 3, a test electrode 4, a data acquisition unit 5, a communication unit 6, a microprocessor 7, a power supply module 8, and a working platform 9.

[0061] The pulse high voltage generator 1 is used to generate a high voltage pulse square wave with adjustable amplitude and width and extremely fast rise time (microsecond level). The pulse is applied to the insulator under test through a capacitive coupler.

[0062] The pulse current sensor 2, employing a Rogowski coil or a high-frequency current transformer, is installed at the low-voltage end of the test electrode 4 to measure the current signal flowing through the insulator under pulse high-voltage excitation, with a frequency band covering 1MHz-100MHz.

[0063] The protection resistor 3 consists of two high-power resistors, which are placed at the high-voltage end and the low-voltage end of the test electrode 4, respectively, to limit the current amplitude generated by the external high voltage acting on the test electrode 4.

[0064] Test electrode 4 is used for electrical contact with the insulator under test. It has a magnetic attraction function for reliable contact, a telescopic function for flexible contact, and a limiting function for adjusting the electrode angle.

[0065] Data acquisition unit 5 includes an electromagnetic shielding shell and a high-resolution ADC module. The electromagnetic shielding shell is made of a high-conductivity material and is equipped with an RF shielding interface to ensure isolation between the internal circuitry and external strong electromagnetic fields. The high-resolution ADC module uses a high sampling rate (≥100MS / s) and high resolution (≥14 bits) analog-to-digital converter to acquire the voltage signal across the insulator under test and the current signal measured by the pulse current sensor 2, converting the filtered analog signal into a digital signal sequence. A comparison of the response signals of a normal insulator and a zero-value insulator before and after filtering under pulse excitation is shown below. Figure 6-9 .

[0066] Communication unit 6 is used to receive control signals and transmit digital signals of pulse voltage and current.

[0067] Power module 7 supplies power to the entire device and can use a rechargeable lithium battery.

[0068] The work platform 9 includes operating platforms such as drones, robots, and insulating rods. The host can rely on the work platform 9 to carry out zero-value live-line testing of porcelain insulators.

[0069] The handheld terminal includes: a wireless communication unit 10, a data processing unit 11, an intelligent diagnostic unit 12, and a human-computer interaction unit 13.

[0070] The wireless communication unit 10 is used to receive the digital signal sequence transmitted from the host communication unit 6.

[0071] The data processing unit 11 is used to process the digital signal sequence transmitted by the wireless communication unit 10. Specifically, the data processing unit 11 uses a band-stop filtering algorithm to further filter out power frequency voltage and current signals, thereby achieving power frequency signal elimination.

[0072] The intelligent diagnostic unit 12 is used to process the data processed by the data processing unit 11 using intelligent diagnostic algorithms.

[0073] 1) Calculate the insulation resistance value based on the pulse voltage and pulse current data after filtering out the power frequency voltage and current.

[0074] 2) Intelligent discharge signal recognition algorithm: Recognizes the discharge signal when the porcelain insulator is broken down by pulse high voltage, and obtains the number of discharges of the porcelain insulator under the action of pulse high voltage.

[0075] 3) Intelligent diagnostic criteria for zero-value insulators: Based on the logical relationship between insulation resistance value and discharge count, the condition of porcelain insulators is diagnosed.

[0076] Human-computer interaction unit 13: includes an LCD screen and buttons, used for parameter setting, result display and status indication.

[0077] like Figure 3 As shown, the test electrode 4 includes a detachable magnetic elastic electrode 101, a spiral electrode support rod 102, a universal connecting flange 103, and a wire connecting rod 104. The spiral electrode support rod 102 is used to connect the detachable magnetic elastic electrode 101 and the universal connecting flange 103. The universal connecting flange 103 is used to connect the spiral electrode support rod 102 and the wire connecting rod 104. The wire connecting rod 104 is connected to the high-voltage pulse generator potting box 105. One side of the high-voltage pulse generator potting box 105 is the wire connecting rod 104, and the other side is the insulator testing device 107. The drone mounting flange 1016 is connected above the insulator testing device 107. Above the insulator testing device 107 are the drone mounting flange 1016 and the communication box 108. On the other side is the connecting operating rod flange 109. The communication box 108 is connected above the insulator testing device 107. The connecting operating rod flange 109 is connected to the insulator testing equipment 107.

[0078] The equipment is used as follows:

[0079] Method 1: After connecting the equipment, the operator can use an insulated operating rod or a robot to connect to the connecting operating rod flange 109. The operator then uses the insulated operating rod or robot to operate the detachable magnetic elastic electrode 101 in the main unit to contact the steel cap and steel feet of the energized insulator under test.

[0080] Method 2: After the operator connects the equipment, they can use the drone mounting flange 106 to connect to the drone. The operator then operates the drone to make the detachable magnetic elastic electrode 101 in the main unit contact the steel cap and steel feet of the energized insulator under test.

[0081] Please see Figure 4 This invention provides a high-precision method for detecting zero-value energization in porcelain insulators, comprising the following steps:

[0082] Step S1: Make contact with both ends of the ceramic insulator under test through the test electrode 4.

[0083] Step S2: Set the amplitude and width of the high voltage pulse output by the pulse high voltage generator 1 via the handheld terminal.

[0084] Step S3: The host is remotely started via a handheld terminal, and the pulse high voltage generator 1 generates a standardized pulse high voltage and applies it to the insulator under test.

[0085] Step S4: The host's data acquisition unit 5 acquires the voltage signal across the porcelain insulator and the current signal flowing through the porcelain insulator, and performs analog-to-digital conversion to obtain a digital signal sequence.

[0086] Step S5: Transmit the digital signal sequence of pulse voltage and current to the handheld terminal through the communication unit 6.

[0087] Step S6: Further filter out the superimposed power frequency voltage and current signals in the pulse voltage and current digital signals through the power frequency signal elimination algorithm to achieve power frequency signal elimination.

[0088] Step S7: Intelligent diagnosis of zero value in porcelain insulators, specifically including:

[0089] S7.1: Calculate the insulation resistance value based on the collected pulse voltage and pulse current.

[0090] S7.2: Intelligent discharge signal recognition algorithm, which identifies the discharge signal when the porcelain insulator is broken down by pulse high voltage, and obtains the number of discharges of the porcelain insulator under the action of pulse high voltage.

[0091] S7.3: Employ a big data model algorithm for defective insulators under wet and dirty conditions, and perform big data model comparison and diagnosis based on the data of each piece of a string of insulators measured in the current measurement.

[0092] S7.4: Intelligent diagnostic criteria for zero-value insulators. Based on the logical relationship between insulation resistance value and discharge count, the status of porcelain insulators is diagnosed as zero value, normal, or retest.

[0093] Step S8: The diagnostic results are displayed through the human-computer interaction unit.

[0094] Among them, such as Figure 5 As shown, the steps of the power frequency signal rejection algorithm are as follows:

[0095] T1, Voltage waveform before applying pulse voltage during live measurement and current waveform .

[0096] T2, Voltage waveform after applying pulse voltage and current waveform .

[0097] The T3, 50Hz power frequency signal has a cycle of 20ms. The power frequency signal is collected in the last 20ms after the test is completed, and the DC component of the current cycle is subtracted to obtain the "clean" power frequency signal.

[0098] T4, Clean Voltage Signal: = ;

[0099] = ;

[0100] Joint diagnostic algorithms such as Figure 10 As shown, the steps are as follows:

[0101] 1. Analyze the voltage waveform to determine if there is a discharge. If a discharge is detected, the value is set to zero.

[0102] 2. Set the zero-value insulator resistance threshold R1 and the high-value resistance threshold R2 according to different insulator models;

[0103] 3. If the insulator resistance value is less than R1, it is judged as zero; if the insulator resistance value is greater than R2, it is judged as high.

[0104] 4. If the insulation resistance value is between R1 and R2 and the voltage waveform shows no discharge, it is considered a high value.

[0105] The advantages of this invention compared to the prior art are:

[0106] 1. Contact measurement under high voltage energized conditions is achieved through electromagnetic shielding design and protection resistor design, avoiding interference from strong electromagnetic fields to the data acquisition unit and the overcurrent effect caused by external high voltage in the test circuit;

[0107] 2. Through filtering algorithms, power frequency voltage and current interference are effectively filtered out, enabling effective extraction of test data.

[0108] 3. Based on the discharge signal identification algorithm and insulation resistance value calculation method under pulsed high voltage, a joint diagnostic criterion of insulation resistance and pulsed high voltage discharge signal is proposed to avoid the inaccuracy problem caused by a single insulation resistance value criterion.

[0109] 4. By comparing and diagnosing the data of each insulator in a series using a big data model, we can avoid the influence of humidity and dirt on the zero-value diagnosis of insulators.

[0110] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A high-precision device for detecting zero-value liveness in porcelain insulators, characterized in that, Includes main unit and handheld terminal; The host includes: A pulse high voltage generator is used to generate and output high voltage pulses and apply them to the insulator under test. Test electrodes are used to make electrical contact with both ends of the energized porcelain insulator under test. A pulse current sensor is used to measure the current signal flowing through the insulator under test under the excitation of the high voltage pulse. The data acquisition unit is used to acquire the voltage signal across the insulator under test and the current signal measured by the pulse current sensor, and perform analog-to-digital conversion to obtain a digital signal sequence. The communication unit is used to transmit signals to the outside world, receive control signals from the handheld terminal, and send digital signal sequences converted from analog to digital by the data acquisition unit. A power module is used to supply power to the host computer; A work platform for mounting the host computer, the work platform including a drone, a robot or an insulating pole; The handheld terminal includes: The wireless communication unit is used to establish a communication connection with the communication unit of the host, output control signals, and receive signals from the host. The data processing unit is used to process the received signals to eliminate power frequency interference; The intelligent diagnostic unit is used to diagnose the condition of the insulator under test by analyzing the insulation resistance value and high-voltage pulse discharge characteristics based on the processed signal. The human-computer interaction unit is used for parameter setting and result display.

2. The apparatus according to claim 1, characterized in that, The host also includes a protection resistor, which includes a first resistor connected in series between the high-voltage end of the test electrode and the pulse high-voltage generator, and a second resistor connected in series between the low-voltage end of the test electrode and ground, for limiting the current introduced by the external high voltage.

3. The apparatus according to claim 1, characterized in that, The data acquisition unit includes an electromagnetic shielding shell and a high-resolution ADC module disposed inside the electromagnetic shielding shell. The electromagnetic shielding shell is provided with a radio frequency shielding interface.

4. The apparatus according to claim 1, characterized in that, The test electrode includes a detachable magnetic elastic electrode, a spiral electrode support rod for connecting and adjusting the electrode, a universal connecting flange, and a wire connecting rod, which is connected to the high-voltage pulse generator potting box.

5. The apparatus according to claim 1, characterized in that, The intelligent diagnostic unit is configured to execute the following diagnostic logic: identify the discharge signal under the action of the high voltage pulse and calculate the insulation resistance value of the insulator under test; perform joint diagnosis based on the logical relationship between the identification result of the discharge signal and the insulation resistance value.

6. The apparatus according to claim 5, characterized in that, The intelligent diagnostic unit is also configured to compare the data of the currently tested insulator with the data of other insulators in the same string using a big data model to assist in diagnosis.

7. The apparatus according to claim 1, characterized in that, The high-resolution ADC module has a sampling rate of ≥100MS / s and a resolution of ≥14 bits.

8. The apparatus according to claim 1, characterized in that, The test electrode also includes a contact state detection module, which is used to detect the contact resistance or contact pressure between the electrode and the insulator under test in real time during the contact step, and to feed back the contact state to the handheld terminal.

9. The apparatus according to claim 1, characterized in that, The host also includes an overcurrent protection module, which automatically cuts off the pulse high voltage output and reports the fault information to the handheld terminal when the detected current exceeds a set threshold.

10. A high-precision method for detecting zero-value energization in porcelain insulators, using the apparatus as described in any one of claims 1-7, characterized in that... The method includes the following steps: Contact step: The test electrode is reliably contacted with both ends of the porcelain insulator under test by using the working platform equipped with the host computer; Excitation step: The handheld terminal is used to set and trigger the high-voltage pulse generator to apply a high-voltage pulse to the insulator under test; Data Acquisition and Transmission Steps: The host computer's data acquisition unit acquires the voltage signal and current signal flowing through the two ends of the insulator under test during the application of the high-voltage pulse, and transmits the converted digital signal sequence to the handheld terminal through the communication unit. Filtering step: In the handheld terminal, a filtering algorithm is used to process the received digital signal sequence to filter out the power frequency interference signal and obtain the filtered pulse response signal; Diagnostic steps: Based on the filtered pulse response signal, calculate the insulation resistance value of the insulator under test, and identify whether a discharge signal is generated under the action of the high voltage pulse; combine the insulation resistance value and the identification result of the discharge signal to diagnose the state of the insulator under test.

11. The method according to claim 10, characterized in that, The filtering step specifically involves using a band-stop filtering algorithm to calculate the signal difference before and after applying the pulsed high voltage, thereby eliminating the power frequency periodic component in the signal.

12. The method according to claim 10, characterized in that, The diagnostic steps specifically include: If a discharge signal is detected, the insulator is diagnosed as having a zero value. If no discharge signal is detected, then determine the calculated insulation resistance value: If the insulation resistance value is lower than the zero-value insulator resistance threshold, it is diagnosed as zero. If the insulation resistance value is higher than the high resistance threshold, it is diagnosed as a high value. If the insulation resistance value is between the zero-value insulator resistance threshold and the high-value resistance threshold, and the voltage waveform does not discharge, it is judged to be a high value.

13. The method according to claim 10, characterized in that, The contact step further includes: monitoring the contact quality in real time through the contact state detection module of the test electrode; if the contact resistance exceeds the set range, issuing an adjustment prompt or interrupting the test.

14. The method according to claim 10, characterized in that, The band-stop filtering algorithm used in the filtering step also includes an adaptive power frequency tracking function, which dynamically adjusts the filtering parameters according to the actual power grid frequency.

15. The method according to claim 10, characterized in that, The diagnostic steps also include: combining historical test data and environmental parameters of each insulator in the same insulator string, and using a machine learning model to assess and correct the confidence level of the current diagnostic results.

Images