Fast Detection Method and Device for Zero-Value Porcelain Insulators Based on Impulse Current Characteristics

Abstract

A method and device for rapid detection of zero value of porcelain insulators based on impulse current characteristics, comprising: applying a high voltage pulse to both ends of the porcelain insulator to be tested; using a magnetic ring to sense the impulse current signal in the insulator loop, and converting it into an integral voltage signal through an integral circuit; comparing the integral voltage signal with a preset threshold, if the integral voltage signal is higher than the preset threshold, the insulator is determined to be a zero value insulator with an internal breakdown defect, and the preset threshold is predetermined according to a given multiple of the integral voltage measured by a normal insulator under the same conditions. By detecting the integral voltage signal of the breakdown current, the present invention effectively avoids misjudgment and missed judgment caused by different surface states or internal defect types of the insulator, improves the accuracy and reliability of the detection, and provides a new and effective means for rapid detection of porcelain insulators.

Description

Technical Field

[0001] The invention relates to a transmission line defect detection and evaluation technology, and in particular to a porcelain insulator zero value rapid detection method and device based on impulse current characteristics. Background Art

[0002] Line insulators are an important part of overhead transmission lines. Their main function is to maintain the mechanical connection and electrical insulation between the transmission conductors and the towers. Disc suspension insulators are one of the most widely used types of insulators in lines. Insulators are subject to various adverse natural environmental influences during operation. In terms of electrical performance, insulators should be able to withstand transient operating overvoltages and lightning overvoltages to ensure that no breakdown occurs; in terms of mechanical performance, insulators must withstand both the mechanical stress caused by the deadweight of the conductors and the thermal and electrical stresses caused by changes in the operating environment. Porcelain insulators are widely used in domestic transmission lines of various transmission levels due to the good chemical stability of their porcelain materials, the ability to withstand adverse environmental conditions, and good heat resistance and aging resistance.

[0003] Traditional porcelain insulator inspection methods include power frequency spark, power frequency withstand voltage, megohmmeter, distributed voltage (live working), spark fork (live working), etc., which have been used in engineering. However, these inspection methods have their own shortcomings. Using a portable impulse voltage generator to generate high-voltage pulses and measure the discharge waveform information has high accuracy and rapid measurement. The principle is to apply a 50-60KV high-voltage pulse at both ends of the insulator, which is aligned with the power frequency withstand voltage test, and the rising edge climbing rate is 1KV / , the falling edge depends on the first-order RC discharge circuit of the insulator. Due to the penetration defects inside the zero-value insulator, internal breakdown will occur at the rising edge of the voltage, and a high-frequency breakdown current with a very large amplitude will be formed. Normal insulators will not have breakdown. After the voltage across the insulator reaches the maximum value (the discharge of the primary side capacitor ends), it will discharge in a first-order RC discharge circuit. As a criterion, first, the amplitude of the charging voltage, which is a method that has been used, and second, the size of the discharge current (collection of the amount of charge). Since the capacitance of insulators with different mechanical loads is different, and the surface condition (contamination, moisture, etc.) will also affect the height of the charging amplitude, in addition, it has been verified in practice that the breakdown voltage amplitude of some insulators with smaller defects is also quite high. Therefore, it is easy to miss and misjudge if only criterion one is used.

[0004] It should be noted that the information disclosed in the above background technology section is only used for understanding the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0005] The main purpose of the present invention is to overcome the defects existing in the above-mentioned background technology and provide a method and device for rapid detection of zero value of porcelain insulator based on impulse current characteristics.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A method for quickly detecting zero value of a porcelain insulator based on impulse current characteristics comprises the following steps:

[0008] Apply high voltage pulses to both ends of the porcelain insulator to be tested;

[0009] Inducing the impulse current signal in the insulator loop through the magnetic ring, and converting the impulse current signal into an integrated voltage signal using an integration circuit;

[0010] The integrated voltage signal is compared with a preset threshold value. If the integrated voltage signal is higher than the preset threshold value, the porcelain insulator is determined to be a zero-value insulator with an internal breakdown defect; wherein the preset threshold value is predetermined according to a given multiple of the integrated voltage measured by a normal insulator under the same conditions.

[0011] A porcelain insulator zero value rapid detection device based on impulse current characteristics, comprising:

[0012] A high-voltage pulse generating circuit is used to generate high-voltage pulses and apply them to both ends of the porcelain insulator to be tested;

[0013] A measuring circuit, comprising a magnetic ring induction unit, an integration circuit and a voltmeter, wherein the magnetic ring induction unit is used to collect a high-frequency breakdown current signal in the insulator circuit, the integration circuit is used to convert the breakdown current signal into an integrated voltage signal, and the voltmeter is used to measure the integrated voltage signal;

[0014] A data processing module is connected to the voltmeter and is used to collect the integrated voltage signal and compare it with a preset threshold value. If the integrated voltage signal is higher than the preset threshold value, the porcelain insulator is determined to be a zero-value insulator with an internal breakdown defect; wherein the preset threshold value is predetermined according to a given multiple of the integrated voltage measured by a normal insulator under the same conditions;

[0015] The present invention has the following beneficial effects:

[0016] The present invention proposes a fast zero-value detection scheme for porcelain insulators. By adopting the impact current characteristic detection technology, it overcomes the limitation of traditional porcelain insulator detection methods that rely on the charging voltage amplitude as a criterion, and proposes a new detection method and device based on the determination of the integral voltage of the impact current. By applying a high-voltage pulse to both ends of the porcelain insulator to be tested, the high-frequency breakdown current signal in the magnetic ring induction loop is utilized, and the impact current is converted into an integral voltage signal through an integrating circuit. By comparing with a preset threshold calibrated based on the experimental data of normal insulators, the risk of misjudgment and missed judgment caused by differences in the surface contamination, humidity and other states of the insulator or different types of internal defects is significantly reduced. Compared with the defect that the traditional single voltage amplitude criterion is easily interfered by capacitance differences and surface states, the present invention realizes accurate determination through the significant difference in integral voltage (the integral voltage of a zero-value insulator can reach several times to dozens of times that of the normal value), effectively adapts to porcelain insulators with different mechanical load levels and complex external insulation conditions, greatly improves the detection reliability, and provides technical guarantee for the operation safety of grid insulators.

[0017] Other beneficial effects in the embodiments of the present invention will be further described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is the overall flowchart of the fast zero-value detection method for porcelain insulators based on the impact current characteristics of the present invention.

[0019] Figure 2 It is the structural schematic diagram of the high-voltage pulse detection device for porcelain insulators in the embodiment of the present invention.

[0020] Figure 3 It is the schematic diagram of the measurement circuit in the embodiment of the present invention.

[0021] Figure 4 It is the working flowchart in the embodiment of the present invention.

[0022] Figure 5 It is the voltage curve at the breakdown moment of the 420KN zero-value insulator in the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The following makes a detailed description of the embodiments of the present invention. It should be emphasized that the following description is merely exemplary and not intended to limit the scope of the present invention and its applications.

[0024] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element. In addition, the connection can be for a fixing function or for a coupling or communication function.

[0025] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0027] At present, the pulse detection method for porcelain insulators generally takes the amplitude of the insulator charging voltage as the zero judgment standard. However, due to the different surface conditions and types of internal defects of the insulators, relying solely on the amplitude as the judgment criterion will result in missed judgments and misjudgments, causing safety hazards. The present invention proposes a porcelain insulator internal defect detection device that can collect impulse currents to achieve accurate detection of internal defects in porcelain insulators. The present invention can perform internal defect detection on porcelain insulators with different mechanical load levels under different external insulation states, effectively prevent power grid accidents caused by the zero value of porcelain insulators, and provide support for the safe operation of the power grid.

[0028] See also Figure 1 The embodiment of the present invention provides a method for quickly detecting the zero value of a porcelain insulator based on the impulse current characteristic, comprising the following steps:

[0029] Apply high voltage pulses to both ends of the porcelain insulator to be tested;

[0030] Inducing the impulse current signal in the insulator loop through the magnetic ring, and converting the impulse current signal into an integrated voltage signal using an integration circuit;

[0031] The integrated voltage signal is compared with a preset threshold value. If the integrated voltage signal is higher than the preset threshold value, the porcelain insulator is determined to be a zero-value insulator with an internal breakdown defect; wherein the preset threshold value is predetermined according to a given multiple of the integrated voltage measured by a normal insulator under the same conditions.

[0032] The high-voltage pulse can be generated by boosting the voltage through a transformer during the charge and discharge process of a discharge capacitor. The integral voltage signal accumulates the electric charge corresponding to the breakdown current, causing a significant difference in the integral voltage between the zero-value insulator and the normal insulator, and realizing zero-value determination through voltage comparison.

[0033] In some embodiments, the process of generating a high-voltage pulse includes: charging the discharge capacitor to a set voltage value; triggering the switch device to conduct, so that the discharge capacitor generates a high-voltage pulse through transformer voltage boosting.

[0034] In some embodiments, the process of converting the impact current signal includes: inducing the high-frequency breakdown current signal in the magnetic ring induction loop, and using an integrating circuit to accumulate the electric charge of the breakdown current; using a fast-recovery diode to suppress current oscillation, so that the integral voltage signal reflects the breakdown current characteristics; by adjusting the parameters of the integrating circuit, making the measurement process sensitive to the high-frequency breakdown current and insensitive to the low-frequency discharge current.

[0035] In some embodiments, the process of determining an internal breakdown defect includes: collecting the voltage signal of the integrating capacitor and comparing it with a preset threshold; if the integral voltage signal is significantly higher than the threshold, it is determined that the insulator has an internal breakdown defect; using the integral voltage difference of the breakdown current as a criterion to eliminate the interference of the insulator surface state on the detection result.

[0036] In some embodiments, the process of determining an internal breakdown defect includes: during the rising edge stage of the high-voltage pulse, monitoring the generation of the breakdown current, and converting the breakdown current into an integral voltage signal through an integrating circuit; converting the integral voltage signal into a digital signal, and processing the digital signal to determine whether it exceeds a preset threshold, and outputting the detection result.

[0037] In some embodiments, the operation flow of the method includes:

[0038] (1) After charging the discharge capacitor to a preset voltage, generating a high-voltage pulse and applying it to the insulator;

[0039] (2) Inducing the loop current through the magnetic ring and converting it into an integral voltage signal;

[0040] (3) Based on the comparison result of the integral voltage amplitude, determining whether the insulator is a zero-value insulator;

[0041] (4) Outputting the detection result through an acoustic and optical prompt or a display screen to achieve fast interactive feedback.

[0042] Refer to Figure 2, a porcelain insulator zero-value rapid detection device based on impulse current characteristics, comprising: a high-voltage pulse generating circuit, used to generate a high-voltage pulse and apply it to both ends of the porcelain insulator to be tested; a measuring circuit, comprising a magnetic ring induction unit, an integration circuit and a voltmeter, the magnetic ring induction unit is used to collect a high-frequency breakdown current signal in the insulator circuit, the integration circuit is used to convert the breakdown current signal into an integrated voltage signal, and the voltmeter is used to measure the integrated voltage signal; a data processing module, connected to the voltmeter, is used to collect the integrated voltage signal and compare it with a preset threshold value, if the integrated voltage signal is higher than the preset threshold value, the porcelain insulator is determined to be a zero-value insulator with an internal breakdown defect; wherein the preset threshold value is predetermined according to a given multiple of the integrated voltage measured by a normal insulator under the same conditions.

[0043] The high-voltage pulse generating circuit can generate high-voltage pulses by controlling the charging and discharging of the discharge capacitor. The measuring circuit accumulates the charge corresponding to the breakdown current through the integrating capacitor, so that the integrated voltage of the zero-value insulator and the normal insulator differ. The data processing module outputs the detection result through voltage comparison.

[0044] See also Figure 2 In some embodiments, the high-voltage pulse generating circuit includes a discharge capacitor C1, a first switch device IGBT1, a second switch device IGBT2, a boost and control circuit, and a transformer T; by controlling the conduction timing of the first switch device IGBT1 and the second switch device IGBT2 located at the front end and the rear end of the boost and control circuit, the boost and control circuit boosts the power supply voltage to a set value and charges the discharge capacitor C1; the transformer T transfers the high-voltage pulse from the primary side to the secondary side and provides a high-voltage pulse for the insulator to be tested; the primary side and the secondary side of the transformer T are respectively connected with diodes, including a primary side diode D1 and a secondary side diode D2; the discharge energy of the discharge capacitor C1 is boosted by the secondary side of the transformer T to form a high-voltage pulse, which is applied to both ends of the insulator to be tested through the air gap formed by the two spherical electrodes. The amplitude and rising rate of the high-voltage pulse are adjustable to meet the breakdown threshold requirements of insulators with different mechanical load levels.

[0045] See also Figure 3 In some embodiments, the integration circuit includes an integration capacitor C2, a resistor R1 and a fast recovery diode D3 arranged in the measurement loop; the combination of the integration capacitor C2 and the resistor R1 realizes sensitive accumulation of high-frequency breakdown current (which can be caused by the impact current) and suppresses the low-frequency discharge current. The fast recovery diode D3 eliminates the current oscillation at the moment of breakdown (including the moment of breakdown caused by the impact current) to ensure the stability of the integrated voltage signal. The measurement loop measures the integrated voltage signal through a voltmeter V.

[0046] In some embodiments, the data processing module includes: an ADC acquisition unit for sampling and obtaining the voltage signal of the integrating capacitor C2; a comparison unit for comparing the voltage signal with a preset threshold, and determining a zero-value insulator if the integrated voltage is significantly higher than the threshold; and a result output unit for feeding back the detection result through an acoustic-optic prompt device or a display screen to achieve user interaction.

[0047] The specific embodiments of the present invention and experimental verification are further described below.

[0048] A method and device for rapid detection of zero value of porcelain insulators, and the structure of the detection device is as Figure 2 shown. The device includes a pulse generation circuit, a measurement circuit, and a data processing module (not shown).

[0049] During actual testing, the porcelain insulator is applied to the high-voltage side. The discharge capacitor C1 discharges when the second switching device IGBT2 is turned on, and the energy is transmitted to the secondary side through the transformer to charge the insulator to be tested. The loop current is extracted by the magnetic ring, and it is determined whether internal breakdown occurs according to the charging voltage of the integrating capacitor C2 in the measurement circuit.

[0050] The principle of the measurement circuit can be explained by a simple R / / C equivalent model of the porcelain insulator. During the charging process of the porcelain insulator, after a normal insulator is charged to about 60 KV, due to the presence of the secondary-side diode D2, it discharges according to a first-order RC circuit; the zero-value insulator will have one or more breakdowns during the voltage boost process, resulting in one or more breakdown currents, which will be induced and collected by the magnetic ring and charge the integrating capacitor C2, causing a significant difference in the integrated voltage signal from that of a normal insulator. By controlling the size of the integrating capacitor C2, the observability of the integrated voltage signal is ensured; by adjusting the value of R1, the high-frequency current is more easily accumulated by the integrating capacitor C2 and is insensitive to the low-frequency current, thereby fully reflecting the effect brought by the breakdown current. Under normal circumstances, the integrated voltage signal of the zero-value insulator is much higher than that of the normal insulator.

[0051] The integrated voltage signal acquired by the voltmeter is compared with the set value after ADC sampling to complete the determination. For example, after testing zero-value and normal insulators of different tonnages under the selected integrating capacitor C2, it is found that the integrated voltage signal shows the data as shown in Table 1. Based on the statistical results of the data in Table 1, it can be seen that for through defects, because the breakdown current is particularly large, the integrated voltage signal The difference is obvious. A wide range from 0.1V to 0.6V can be used as the discrimination value. When m is smaller, it is more sensitive to the breakdown current and thus more sensitive to local defects. Here, m = 0.3V is taken as a compromise. When , it is determined as a zero-value insulator; when , it is determined as a normal insulator.

[0052] During the process of the voltage at both ends of the insulator rising, since the capacitances of the zero-value and normal insulators are not much different, the impulse currents generated due to the change in the capacitive reactance of the insulator during this process are also not much different. During this process, the amount of charge flowing through the insulator is small; in addition, a breakdown current will be generated during the breakdown process of the zero-value insulator, which is the source of the difference in the integral voltage signal . The formula is as follows:

[0053]

[0054] Since the amplitude and frequency of the breakdown current are extremely high, it is not convenient to sample directly with a current transformer. Only a Rogowski coil can be used to collect its waveform. Therefore, this integration circuit is designed to reflect the existence of the breakdown current by the difference in the integral voltage signal . Due to the high-frequency characteristics of the breakdown current, the fast-recovery diode D3 prevents the current from oscillating at the moment of breakdown, affecting the discrimination of the integral voltage signal .

[0055] Taking the existence or non-existence of the breakdown current as the criterion for judgment is less affected by the surface state of the insulator. Even if the surface resistance is very small, since only whether internal breakdown occurs is concerned, no misjudgment will occur; for insulators with a maximum mechanical load of 550KN, when the outer surface is clean, it is ensured that the peak value of the pulse voltage can reach 60KV. As long as any insulator with any mechanical load level has internal breakdown, there will definitely be a breakdown current, so no missed judgment will occur.

[0056] The operation logic of the zero-value rapid detection device for porcelain insulators is as follows:

[0057] Step 1: Charge the discharge capacitor C1. The power supply boosts the voltage of the discharge capacitor C1 to the set value through the boost and control circuit.

[0058] Step 2: Discharge the discharge capacitor C1 to form a high-voltage pulse on the secondary side through the transformer boost. Both the first switching device IGBT1 and the second switching device IGBT2 are controlled by the MCU. When the discharge capacitor C1 is charged to the set value, the MCU controls the second switching device IGBT2 to conduct and start discharging. The energy is transferred to the secondary side through the transformer to charge the insulator.

[0059] Step 3: Measure and judge. The magnetic ring senses the loop current and hands it over to the measurement loop for integral processing. The ADC samples the integral voltage signal , perform a comparison and judgment. For example, at a selected specific value of the integral capacitor C2, the data shown in Table 1 is presented. According to the test data in Table 1, the critical value m can be set to 0.3V. When , it is determined as a zero-value insulator; when , it is determined as a normal insulator. The result can be prompted through a display screen and a sound, enhancing the simplicity of device use.

[0060] Figure 2 is a schematic structural diagram of the high-voltage pulse detection device for porcelain insulators according to an embodiment of the present invention. Figure 3 is the measurement circuit according to an embodiment of the present invention. Figure 4 shows the working process of the device, including: Step S1: Test preparation. Connect the insulator to the high-voltage end. Step S2: Detection. Press the detection button, and the MCU automatically charges the discharge capacitor C1 to the set value and then discharges it to form a high-voltage pulse on the secondary side. Step S3: Output the result. The detection circuit collects the current information during the pulse process, makes a comparison and judgment. The detection result is prompted through a display screen and a sound.

[0061] Figure 5 is the breakdown moment voltage curve of a non-standard zero-value insulator 420KN-3. Its impulse voltage peak is higher than 55KV and it breaks down at the falling edge. If a single voltage amplitude is used as the criterion, it may be misjudged as a normal insulator. The embodiment of the present invention is based on the impulse current characteristic, and by detecting the integral voltage signal of the breakdown current generated by the insulator under the action of a high-voltage pulse and comparing it with a preset threshold value, it effectively avoids misjudgment and missed judgment caused by different surface states or internal defect types of the insulator, thereby realizing the accurate determination of normal insulators and zero-value insulators.

[0062] Table 1 shows the integral voltage signals for comparing zero-value and normal insulators differences.

[0063] Table 1 of the insulator measured data

[0064]

[0065] It can be seen that generally, for zero-value and normal insulators, the integral voltage signal difference can reach more than 10 times. This huge gap reflects the superiority of the criterion used in the present invention.

[0066] In summary, the present invention proposes a method and device for rapid zero-value detection of porcelain insulators based on impulse current characteristics, and designs a high-voltage pulse detection circuit for porcelain insulators and a new zero-value judgment method. Through the measurement circuit of the current integration method, the breakdown current of zero-value insulators, which is different from normal insulators, is highlighted, and the integrated voltage is used as the zero-value judgment standard. Thus, the possibility of missing judgment is greatly reduced. Compared with the traditional method of judging by the amplitude of the impulse voltage, the present invention is more adaptable to insulators with different mechanical load levels and complex external surface insulation conditions. Based on the acquisition of impulse current and zero-value discrimination to detect the through defects existing inside the porcelain insulator, the present invention can accurately detect the long-term operation process and factory defects of the porcelain insulator, and effectively improve the reliability of the insulator operation.

[0067] The above content is a further detailed description of the present invention in combination with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present invention is only limited to these descriptions. For those of ordinary skill in the technical field to which the present invention pertains, without departing from the concept of the present invention, several alternatives or modifications can be made to these described embodiments, and these alternative or modified forms should all be regarded as belonging to the protection scope of the present invention. In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "preferred embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. Without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. Although the embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions, and alterations can be made herein without departing from the protection scope of the patent application.

Claims

1. A rapid zero-value detection method for porcelain insulators based on impulse current characteristics, characterized in that It includes the following steps: Apply a high-voltage pulse across the porcelain insulator to be tested; Induce the impulse current signal in the insulator loop through a magnetic ring, and convert the impulse current signal into an integral voltage signal by using an integrating circuit; Compare the integral voltage signal with a preset threshold. If the integral voltage signal is higher than the preset threshold, it is determined that the porcelain insulator is a zero-value insulator with an internal breakdown defect; wherein the preset threshold is predetermined as a given multiple of the integral voltage measured for a normal insulator under the same conditions.

2. The zero-value rapid detection method for porcelain insulators based on impulse current characteristics according to claim 1, wherein The process of generating a high-voltage pulse includes: charging a discharge capacitor to a set voltage value; triggering a switching device to conduct, so that the discharge capacitor generates a high-voltage pulse with a set amplitude and rising rate through a transformer boost.

3. The zero-value rapid detection method for porcelain insulators based on impulse current characteristics according to claim 1, characterized in that The process of converting the impulse current signal includes: Induce the high-frequency breakdown current signal in the loop through a magnetic ring, and accumulate the charge quantity of the breakdown current by using an integrating circuit; Suppress current oscillation through a fast-recovery diode, so that the integral voltage signal reflects the breakdown current characteristics; The parameters of the integrating circuit are configured so that the measurement process is sensitive to high-frequency breakdown current and insensitive to low-frequency discharge current.

4. The zero-value rapid detection method for porcelain insulators based on impulse current characteristics according to claim 1, characterized in that, The process of determining an internal breakdown defect includes: During the rising edge stage of the high-voltage pulse, monitor the generation of the breakdown current, and convert the breakdown current into an integral voltage signal through an integrating circuit; Convert the integral voltage signal into a digital signal, process the digital signal to determine whether it exceeds a preset threshold, and output a detection result.

5. The zero-value rapid detection method for porcelain insulators based on impulse current characteristics according to any one of claims 1 to 4, characterized in that The operation flow of the method includes: (1) After charging the discharge capacitor to a preset voltage, generate a high-voltage pulse and apply it to the insulator; (2) Induce the loop current through a magnetic ring and convert it into an integral voltage signal; (3) Based on the comparison result of the integral voltage amplitude, determine whether the insulator is a zero-value insulator; (4) Output the detection result through an acoustic-optic prompt or a display screen to achieve fast interactive feedback.

6. A zero-value rapid detection device for porcelain insulators based on impulse current characteristics, characterized in that, It includes: A high-voltage pulse generation circuit for generating a high-voltage pulse and applying it across the porcelain insulator to be tested; A measurement circuit, including a magnetic ring induction unit, an integrating circuit and a voltmeter. The magnetic ring induction unit is used to collect the high-frequency breakdown current signal in the insulator loop, the integrating circuit is used to convert the breakdown current signal into an integral voltage signal, and the voltmeter is used to measure the integral voltage signal; A data processing module, connected to the voltmeter, for collecting the integral voltage signal and comparing it with a preset threshold. If the integral voltage signal is higher than the preset threshold, it is determined that the porcelain insulator is a zero-value insulator with an internal breakdown defect; wherein the preset threshold is predetermined as a given multiple of the integral voltage measured for a normal insulator under the same conditions.

7. The porcelain insulator zero-value rapid detection device according to claim 6, characterized in that, The high-voltage pulse generation circuit includes a discharge capacitor, a switching device, a boost and control circuit, and a transformer; By controlling the conduction timing of the switching device, the boost and control circuit boosts the power supply voltage to a set value and charges the discharge capacitor; The transformer transfers the high-voltage pulse from the primary side to the secondary side and provides a high-voltage pulse for the insulator to be tested; The discharge energy of the discharge capacitor forms a high-voltage pulse after being stepped up by the secondary side of the transformer and is applied to both ends of the insulator to be measured.

8. The porcelain insulator zero-value rapid detection device according to claim 6 or 7, characterized in that, The integration circuit includes an integration capacitor, a resistor, and a fast-recovery diode provided in the measurement loop; The combination of the integration capacitor and the resistor realizes sensitive accumulation of the high-frequency breakdown current while suppressing the low-frequency discharge current. The fast-recovery diode eliminates the current oscillation at the moment of breakdown to ensure the stability of the integrated voltage signal.

9. The porcelain insulator zero-value rapid detection device according to claim 6 or 7, characterized in that, The data processing module includes: an ADC acquisition unit for sampling and obtaining the voltage signal of the integration capacitor; a comparison unit for comparing the voltage signal with a preset threshold, and determining the insulator as a zero-value insulator if the integrated voltage is significantly higher than the threshold; a result output unit for feeding back the detection result through an acoustic-optic prompt device or a display screen to achieve user interaction.

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