Active detection device and method for line insulator discharge defect

Abstract

An active detection device and method for a line insulator discharge defect. The device comprises: a repetition-rate X-ray pulsed light source, a solar-blind ultraviolet photosensitive detection unit, a switching value counter, an ultrasonic ranging unit, an information computing unit, and an execution control unit. The repetition-rate X-ray pulsed light source is configured to generate X-ray pulses at a repetition rate. The ultrasonic ranging unit is configured to obtain the distance between the solar-blind ultraviolet photosensitive detection unit and an insulator under test. The solar-blind ultraviolet photosensitive detection unit, the switching value counter, and the information computing unit are connected in sequence. The solar-blind ultraviolet photosensitive detection unit is configured to detect insulating discharge ultraviolet photons generated after X-ray excitation. The switching value counter is configured to count high-level pulse sequences outputted by the solar-blind ultraviolet photosensitive detection unit. The information computing unit is configured to process information outputted by the switching value counter and provide a state determination result of the insulator under test.

Description

Active detection device and method for discharge defects in line insulators

[0001] This application claims priority to Chinese Patent Application No. 202411915858.0, filed with the Chinese Patent Office on December 24, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of transmission line insulation testing technology, and for example to an active detection device and method for discharge defects in line insulators. Background Technology

[0003] Sudden short circuits in power transmission lines pose a significant threat to the safe operation of the power grid, and contamination, aging, or defects in insulators are a major cause of these faults. Insulators perform both mechanical support and electrical insulation functions in power lines. Operating under complex atmospheric conditions such as ultraviolet radiation, high humidity, dust, salt spray, rain, and snow, they inevitably accumulate dirt, age, and cracks, accelerating insulation failure. Generally, when aging or defects reach a certain level, abnormal discharge phenomena occur under voltage, allowing for the detection of insulation defects using discharge detection technology. However, most partial discharges caused by defects are not continuous and stable; they are insidious, sporadic, and random, sometimes even not obvious under operating voltage. In recent years, several insulator flashover accidents have occurred without obvious pre-discharge signs, highlighting the urgent need to explore sensitive and efficient new methods for insulator defect detection.

[0004] Traditional insulator defect detection methods mainly include the following: ultrasonic detection, where insulator discharge causes rapid thermal expansion and contraction of the local medium, resulting in mechanical waves propagating in different media; ultrasonic signals from insulator discharge can be obtained through ultrasonic coupling sensors; infrared thermal imaging, where discharge energy is strong enough and duration is long enough to cause local heating, and abnormal temperature rises can be detected using infrared thermal imagers to indirectly reflect the discharge situation; and solar-blind ultraviolet imaging, where discharge on the insulator surface causes light emission in the ultraviolet band, and photon imaging detection using the solar-blind band can effectively detect discharge signals while avoiding sunlight interference. However, the main problems with the above detection methods are: ① The operating voltage of insulators is generally much lower than the design field strength, while the critical electric field for insulation defect discharge is high, making it difficult to induce stable discharge under a limited electric field; ② Under limited voltage levels, local discharge of insulation defects often exhibits strong sporadicity, with amplitudes lower than the detection threshold; ③ Conventional detection methods are all passive detection methods, and defect-induced discharge requires specific conditions, such as increased defect size, high humidity, and material aging, making it difficult to capture discharge signals within a limited detection time. Summary of the Invention

[0005] This application provides an active detection device and method for discharge defects in line insulators, providing an active discharge detection technology for the rapid identification of defects in line insulators.

[0006] The first aspect of this application provides an active detection device for discharge defects in line insulators, the device comprising:

[0007] The system includes a high-repetition-rate X-ray pulse source, a solar-blind ultraviolet photosensitive detection unit, a switch counter, an ultrasonic ranging unit, an information computing unit, and an execution control unit.

[0008] The execution control unit is connected to the high-repetition-rate X-ray pulse source, the solar-blind ultraviolet photosensitive detection unit, the switch counter, the ultrasonic ranging unit, and the information calculation unit, respectively. The execution control unit is configured to control at least one of the following: the start and end times of operation and the output parameters of the high-repetition-rate X-ray pulse source, the solar-blind ultraviolet photosensitive detection unit, the switch counter, the ultrasonic ranging unit, and the information calculation unit.

[0009] The high-repetition-rate X-ray pulse source is configured to generate X-ray light pulses with a repetitive frequency. The ultrasonic ranging unit is configured to obtain the distance between the solar-blind ultraviolet photosensitive detection unit and the insulator under test. The solar-blind ultraviolet photosensitive detection unit, the switch counter, and the information calculation unit are connected in sequence. The solar-blind ultraviolet photosensitive detection unit is configured to detect the ultraviolet photons of insulation discharge generated after X-ray excitation. The switch counter is configured to count the high-level pulse sequence output by the solar-blind ultraviolet photosensitive detection unit. The information calculation unit is configured to process the information output by the switch counter and give the state judgment result of the insulator under test.

[0010] The irradiation angle of the repetitive X-ray pulse source is not less than 15°, the center wavelength range is 0.5 to 10 nm, the controllable dose range of a single pulse X-ray is 5 to 15 μSv, the controllable pulse half-peak time is 0.5 to 5 μs, and the optical pulse repetition frequency is adjustable within 10 to 50 Hz.

[0011] In some embodiments, the response wavelength range of the solar-blind ultraviolet photosensitive detection unit is 240–280 nm, the photon efficiency in the solar-blind band is not less than 15%, the photopulse response time is less than 200 ns, the effective detection angle θ includes at least -30° to +30°, and the photoelectric gain is not less than 60 dB.

[0012] In some embodiments, the solar-blind ultraviolet photosensitive detection unit receives a photon signal and then outputs a high-level square wave pulse signal with a pulse width of less than 200 ns.

[0013] In some embodiments, the execution control unit is configured to control the start and stop of operation and output parameters of the high-repetition-rate X-ray pulse source, the start and stop of operation of the solar-blind ultraviolet photosensitive detection unit, the start and stop of operation and output parameters of the switch counter, and the start and stop of operation of the information calculation unit.

[0014] The second aspect of this application provides an active detection method for discharge defects in line insulators, applied to the active detection device for discharge defects in line insulators described in the first aspect of this application, comprising:

[0015] By activating the solar-blind ultraviolet photosensitive detection unit through the execution control unit, the background light pulse when no X-rays are applied is measured to obtain the average discharge frequency within time T, which is denoted as n0.

[0016] The controllable dose R of a single pulse of X-rays from a high-repetition-rate X-ray pulse source is set by the execution control unit;

[0017] The control unit activates a high-repetition-rate X-ray pulse source to irradiate the target area of ​​the insulator of the line under test.

[0018] The control unit activates the solar-blind ultraviolet photosensitive detection unit immediately after the pulse output of the high-repetition-rate X-ray pulse source ends, and the detection frequency is consistent with the X-ray pulse repetition frequency.

[0019] By starting the switch counter through the execution control unit and keeping it consistent with the working time of the repetition rate X-ray pulse source, the frequency of the discharge light pulse in the X-ray pulse interval time Δt is obtained and denoted as n.

[0020] The ultrasonic ranging unit is activated by the execution control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source to obtain the ultrasonic ranging value L in the X-ray pulse interval time Δt.

[0021] The information calculation unit is activated by the execution control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source. The excitation intensity S of the discharge photons at time t is calculated. Based on the calculation result of the excitation intensity S of the discharge photons, the information calculation unit gives a graded evaluation result and obtains the discharge state of the insulator of the line under test.

[0022] In some embodiments, the control unit activates a high-repetition-rate X-ray pulse source to irradiate the target area of ​​the insulator of the line under test, and the cumulative X-ray dose is not higher than 10 mSv.

[0023] In some embodiments, the discharge photon excitation intensity S at time t is calculated using the following formula:

[0024] In the formula, n(t) is the frequency of the X-ray discharge light pulse at time t, n0 is the average discharge frequency of the background light pulse when no X-ray is applied within time T, L(t) is the ultrasonic ranging value at time t, R is the controllable dose of a single pulse of X-ray from the repetitive X-ray pulse source, and θ is the effective detection angle of the solar-blind ultraviolet photosensitive detection unit.

[0025] In some embodiments, the tiered evaluation results provided by the information computing unit include normal, attention, tracking, early warning, and alarm.

[0026] In some embodiments, the information calculation unit provides a graded evaluation result based on the calculation result of the discharge photon excitation intensity S, including:

[0027] Set a valid test value m;

[0028] Input data S(t) i ), in response to S(t) i If )≤0, the output grading evaluation result is normal;

[0029] Response to S(t) i If S(t) > 0, test the data. i Whether it is valid; response to |S(t) i )-S(t i-1 If | ≤ m, confirm the data S(t) i ) Valid, proceed to the next evaluation process;

[0030] Response to S(t) i If a ≤ a1, the output classification assessment result is "concerned"; responding to a1 <S(t i If a ≤ a2, the output hierarchical evaluation result is tracking; the response is a2. <S(t i If a ≤ a3, the output classification assessment result is a warning; the response is a3. <S(t i The output of the graded assessment result is an alarm;

[0031] Where i is a positive integer, and a1, a2 and a3 are state thresholds. Attached Figure Description

[0032] Figure 1 is a schematic diagram of the hardware configuration of a solar-blind ultraviolet photon detection device based on an X-ray source;

[0033] Figure 2 shows the startup sequence of a solar-blind ultraviolet photon detection device based on an X-ray source during operation;

[0034] Figure 3 is a flowchart illustrating the hierarchical evaluation logic based on the excitation intensity S of the discharge photons.

[0035] Figure 4 is a schematic diagram of the results of a hierarchical evaluation logic based on the excitation intensity S of the discharge photons in some implementations. Detailed Implementation

[0036] The embodiments of this application will now be described with reference to the accompanying drawings. The described embodiments are some examples related to this application. Based on the spirit of this application, all other embodiments obtained by those skilled in the art without inventive effort are within the protection scope of this application.

[0037] Theoretically, the necessary condition for insulation defects to discharge is that the applied electric field strength exceeds the critical field strength for defect discharge. Therefore, micro-defects are not necessarily accompanied by discharge phenomena, and with the increase in service life, potential defects may rapidly develop into sudden insulation faults. Under short-wavelength external irradiation such as X-rays, insulation defects can generate stable discharges at lower electric fields, thereby reducing the partial discharge field threshold and facilitating rapid and effective defect detection. Therefore, this application proposes an active light source-excited insulator discharge defect detection technology, which is applicable to UAVs and can be used for active, rapid, and accurate detection of line insulator defects.

[0038] This application provides an active detection device for discharge defects in line insulators in Embodiment 1. As shown in Figure 1, the hardware configuration of this device is a solar-blind ultraviolet photon detection device based on an X-ray source, including: a high-repetition-rate X-ray pulse source, a solar-blind ultraviolet photosensitive detection unit, a switching counter, an ultrasonic ranging unit, an information calculation unit, and an execution control unit.

[0039] The execution control unit is connected to the high-repetition-rate X-ray pulse source, the solar-blind ultraviolet photosensitive detection unit, the switch counter, the ultrasonic ranging unit, and the information calculation unit, respectively. The solar-blind ultraviolet photosensitive detection unit, the switch counter, and the information calculation unit are connected in sequence. The execution control unit controls the high-repetition-rate X-ray pulse source to irradiate the insulator being tested. During the interval period after the high-repetition-rate pulse source irradiation, the solar-blind photosensitive sensor detects the discharge photon signal and transmits it to the switch counter. The information calculation unit evaluates the strength of the discharge signal by using the distance information obtained by the ultrasonic ranging unit and the photon count result obtained by the switch counter.

[0040] In some embodiments, the device is a functional payload for unmanned aerial vehicle (UAV) power line inspection, used for online detection of various line insulator defects and abnormal discharges.

[0041] In some embodiments, the high-repetition-rate X-ray pulse source is configured to generate X-ray light pulses with a repetition frequency.

[0042] For example, the irradiation angle of the high-repetition-rate X-ray pulse source is not less than 15°, the center wavelength should be within the soft X-ray range (0.5–10 nanometers (nm)), the controllable dose range of a single pulse X-ray is 5–15 microsieverts (μSv), the controllable half-peak time of the pulse is 0.5–5 microseconds (μs), and the optical pulse repetition frequency is adjustable within 10–50 hertz (Hz). The peak output power and half-peak time of the pulse source are both adjusted by the execution control unit.

[0043] In some embodiments, the solar-blind ultraviolet photosensitive detection unit is configured to detect insulating discharge ultraviolet photons generated after X-ray excitation; the response wavelength range of the solar-blind ultraviolet photosensitive detection unit is the solar-blind ultraviolet band (240-280nm), the photon efficiency in the solar-blind band is not less than 15%, the photopulse response time is less than 200 nanoseconds (ns), the effective detection angle θ includes at least -30° to +30°, and this detection angle is symmetrical with the horizontal line as the axis of symmetry, the photoelectric gain is not less than 60 dB, and when the photon signal is received, a high-level square wave pulse signal can be output with a pulse width of less than 200 ns.

[0044] In some embodiments, the switch counter is configured to count the high-level pulse sequence output by the solar-blind ultraviolet photosensitive detection unit, and the number of light pulses in the output X-ray pulse interval time Δt is denoted as n;

[0045] In some embodiments, the ultrasonic ranging unit is configured to obtain the distance between the solar-blind ultraviolet photosensitive detection unit and the detection object, and output the ultrasonic ranging value L in the X-ray pulse interval time Δt, denoted as L.

[0046] In some embodiments, the information calculation unit is configured to process the output information of the switch counter, calculate the discharge photon excitation intensity according to the calculation steps of the discharge photon excitation intensity S, and give the state determination result.

[0047] For example, the status determination results include normal, attention, tracking, early warning, and alarm.

[0048] In some embodiments, the execution control unit is configured to control the start and stop of operation and output parameters of the high-repetition-rate X-ray pulse source, the start and stop of operation of the solar-blind ultraviolet photosensitive detection unit, the start and stop of operation and output parameters of the switch counter, and the start and stop of operation of the information calculation unit;

[0049] In some embodiments, the execution of commands by the control unit can be controlled by a host computer.

[0050] This application provides an active detection method for discharge defects in line insulators in Embodiment 2, which is applied to the active detection device for discharge defects in line insulators described in Embodiment 1 of this application, and includes the following steps:

[0051] By activating the solar-blind ultraviolet photosensitive detection unit through the execution control unit, the background light pulse when no X-rays are applied is measured to obtain the average discharge frequency within time T, denoted as n0 (unit: seconds). -1 For example, the rounding of T is as follows:

[0052] Where k is a positive integer and f is the power grid frequency AC cycle;

[0053] The controllable dose R (unit: μSv) of a single pulse of X-ray from a high-repetition-rate X-ray pulse source is set by the execution control unit;

[0054] The control unit activates a high-repetition-rate X-ray pulse source to irradiate the target area of ​​the line insulator, with the cumulative X-ray dose not exceeding 10 mSv;

[0055] The control unit activates the solar-blind ultraviolet photosensitive detection unit immediately after the pulse output of the high-repetition-rate X-ray pulse source ends, and the detection frequency is consistent with the X-ray pulse repetition frequency.

[0056] By activating the switch counter through the control unit and keeping it consistent with the working time of the high-repetition-rate X-ray pulse source, the frequency of the discharge light pulse in the X-ray pulse interval Δt is obtained and denoted as n (unit: s). -1 );

[0057] The ultrasonic ranging unit is started by executing the control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source. The ultrasonic ranging value L in the X-ray pulse interval time Δt is obtained and denoted as L (unit: meters (m)).

[0058] The startup sequence of the solar-blind ultraviolet photon detection device based on an X-ray source is shown in Figure 2.

[0059] The information calculation unit is activated by the execution control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source. The excitation intensity S of the discharge photons at time t is calculated according to the following formula (unit: microsieverts per second per meter (μSv·s)). -1 ·m)) is used for calculation:

[0060] In the formula, n(t) is the frequency of the X-ray discharge light pulse at time t, n0 is the average discharge frequency of the background light pulse when no X-ray is applied within time T, L(t) is the ultrasonic ranging value at time t, R is the controllable dose of a single pulse of X-ray from the repetitive X-ray pulse source, and θ is the effective detection angle of the solar-blind ultraviolet photosensitive detection unit.

[0061] In some embodiments, the tiered evaluation results provided by the information computing unit include normal, attention, tracking, early warning, and alarm.

[0062] As shown in Figure 3, the information computing unit provides a graded evaluation result based on the calculation result of the discharge photon excitation intensity S according to the following judgment logic:

[0063] Set a valid test value m;

[0064] Input S(t) i If S(t) i If )≤0, then the output graded evaluation result is normal;

[0065] If S(t) i If )>0, then test the data S(t) i Whether |S(t) is valid, if |S(t) i )-S(t i-1 If | ≤ m, then the data S(t) is considered to be... i If |S(t) is valid, proceed to the next evaluation process; if |S(t) is valid, proceed to the next evaluation process. i )-S(t i-1 If |>m, then the data S(t) is considered to be... i If invalid, enter the next data and repeat the above process;

[0066] For S(t) i )>0, and S(t) i )-S(t i-1 )|≤m valid data, if S(t) i If a) ≤ a1, then the output graded evaluation result is "concerned"; if a1 ≤ ..., then the output graded evaluation result is "concerned". <S(t i If a) ≤ a2, then the output hierarchical evaluation result is tracking; if a2 <S(t i If a) ≤ a3, then the output graded evaluation result is a warning; if a3 <S(t i If the output is a tiered assessment result, then an alarm will be generated.

[0067] Where i is a positive integer, i can take the values ​​1, 2, 3, ...; m is the valid check value, for example, m = 100; a1, a2, and a3 are state thresholds, the values ​​of a1, a2, and a3 can be given by the insulator type and voltage level, for example, a1 = 250, a2 = 580, a3 = 1000, unit: μSv·s -1 ·m.

[0068] The following describes method embodiments of this application to enable those skilled in the art to understand the nature and scope of this application.

[0069] In some embodiments, a physical detection device was fabricated using the hardware structure and working principle of the solar-blind ultraviolet photon detection device based on an X-ray source proposed in this application. The physical detection device was mounted on a UAV gimbal (e.g., the UAV model can be selected as M300 RTK), realizing UAV mounting. The physical detection device was then applied to the detection of defects in insulators of 10 kV distribution lines, and the defect status of the insulators was ultimately determined to be a warning state.

[0070] The following explains how to apply the principles and processes of this application to achieve the above effects:

[0071] By activating the solar-blind ultraviolet photosensitive detection unit through the execution control unit, the background light pulse when no X-rays are applied is measured, and the average discharge frequency n0 within a time T (T = 100 milliseconds (ms)) is obtained as 210 / s;

[0072] The controllable dose of a single pulse of X-ray from the high-repetition-rate X-ray pulse source is set to R = 8 μSv, and the pulse width is 2 μs by the execution control unit.

[0073] The control unit activates a high-repetition-rate X-ray pulse source to irradiate the target area of ​​the line insulator. The repetition rate is 30 Hz and the cumulative X-ray dose is 3.6 mSv (i.e., the total pulse application time is 15 seconds).

[0074] The control unit activates the solar-blind ultraviolet photosensitive detection unit immediately after the pulse output of the high-repetition-rate X-ray pulse source ends, and the detection frequency is consistent with the X-ray pulse repetition frequency.

[0075] By activating the switch counter through the control unit and keeping it consistent with the working time of the high-repetition-rate X-ray pulse source, the discharge pulse frequency n in the X-ray pulse interval time Δt = 33.331 ms was found to be 420–480 s. -1 ;

[0076] The ultrasonic ranging unit is activated by the execution control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source to obtain the ultrasonic ranging value L = 3.1 to 3.3 m in the X-ray pulse interval time Δt.

[0077] The information calculation unit is activated by the execution control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source. The excitation intensity S of the discharge photons at time t (unit: μSv·s) is calculated according to the following formula. -1Perform calculations with θ = 30°, L = 3.2, n = 433, and n0 = 210 as an example in the following formula:

[0078] Based on the calculation result of the discharge photon excitation intensity S, where a2 < S ≤ a3 (taking a2 = 580 and a3 = 1000 as an example), according to the judgment logic (as shown in Figure 4), the hierarchical evaluation result is determined to be a warning, indicating that the discharge state of the insulator of the measured line is: warning.

[0079] In some embodiments, the present application also provides a system for actively detecting discharge defects of line insulators. This system consists of a device for actively detecting discharge defects of line insulators and a method for actively detecting discharge defects of line insulators. It can utilize the principle of reducing the discharge electric field threshold with a short-wave light source to transform passive discharge detection into active discharge detection, shorten the discharge detection time, improve the discharge activity within the detection period, and借助无人机实现各类线路绝缘子的快速、准确、主动检测,提升线路外绝缘的检测运维效率。(The Chinese part here seems to be incomplete. It should be something like "achieve fast, accurate, and active detection of various line insulators with the help of drones, and improve the detection and operation and maintenance efficiency of the external insulation of the line.")

[0080] Compared with conventional ultrasonic detection, infrared imaging, and ultraviolet imaging detection technologies, the device and method for actively detecting discharge defects of line insulators proposed in the present application have the following significant advantages:

[0081] 1) By using a drone to carry a system composed of a device for actively detecting discharge defects of line insulators and its related detection methods, it can quickly cover a large area of power lines, significantly improve the detection efficiency, and achieve tower-by-tower detection.

[0082] 2) Use an x-ray pulse light source for active irradiation to transform traditional passive discharge detection into active discharge detection, which can effectively excite stable discharges from defects in a short time, shorten the detection waiting time, and improve the detection efficiency.

[0083] 3) Reduce the discharge electric field threshold through an ultraviolet light source, which is not limited by the atmospheric environment and operating voltage.

Claims

1. An active detection device for discharge defects in line insulators, comprising: The system includes a high-repetition-rate X-ray pulse source, a solar-blind ultraviolet photosensitive detection unit, a switch counter, an ultrasonic ranging unit, an information computing unit, and an execution control unit. The execution control unit is connected to the high-repetition-rate X-ray pulse source, the solar-blind ultraviolet photosensitive detection unit, the switch counter, the ultrasonic ranging unit, and the information calculation unit, respectively. The execution control unit is configured to control at least one of the following: the start and end times of operation and the output parameters of the high-repetition-rate X-ray pulse source, the solar-blind ultraviolet photosensitive detection unit, the switch counter, the ultrasonic ranging unit, and the information calculation unit. The high-repetition-rate X-ray pulse source is set to generate X-ray light pulses with a repetition frequency, and the ultrasonic ranging unit is set to obtain the distance between the solar-blind ultraviolet photosensitive detection unit and the insulator under test. The solar-blind ultraviolet photosensitive detection unit, the switch counter, and the information calculation unit are connected in sequence. The solar-blind ultraviolet photosensitive detection unit is set to detect the ultraviolet photons of insulation discharge generated after X-ray excitation. The switch counter is set to count the high-level pulse sequence output by the solar-blind ultraviolet photosensitive detection unit. The information calculation unit is set to process the information output by the switch counter and give the state judgment result of the insulator under test.

2. The active detection device for discharge defects in line insulators according to claim 1, wherein: The irradiation angle of the repetitive X-ray pulse source is not less than 15 degrees, the center wavelength range is 0.5 to 10 nanometers, the controllable dose range of a single pulse X-ray is 5 to 15 microsieverts, the controllable pulse half-peak time is 0.5 to 5 microseconds, and the optical pulse repetition frequency is adjustable within 10 to 50 Hz.

3. The active detection device for discharge defects in line insulators according to claim 1, wherein: The solar-blind ultraviolet photosensitive detection unit has a response wavelength range of 240–280 nm, a photon efficiency of not less than 15% in the solar-blind band, a light pulse response time of less than 200 nanoseconds, an effective detection angle θ of at least -30 degrees to +30 degrees, and a photoelectric gain of not less than 60 dB.

4. The active detection device for discharge defects in line insulators according to claim 1, wherein: The solar-blind ultraviolet photosensitive detection unit receives photon signals and outputs a high-level square wave pulse signal with a pulse width of less than 200 nanoseconds.

5. The active detection device for discharge defects in line insulators according to claim 1, wherein: The execution control unit is configured to control the start and end of operation and output parameters of the high-repetition-rate X-ray pulse source, the start and end of operation of the solar-blind ultraviolet photosensitive detection unit, the start and end of operation and output parameters of the switch counter, and the start and end of operation of the information calculation unit.

6. A method for actively detecting discharge defects in line insulators, applied to the active detection device for discharge defects in line insulators as described in any one of claims 1-5, comprising: By activating the solar-blind ultraviolet photosensitive detection unit through the execution control unit, the background light pulse when no X-rays are applied is measured to obtain the average discharge frequency within time T, which is denoted as n0. The controllable dose R of a single pulse of X-rays from a high-repetition-rate X-ray pulse source is set by the execution control unit; The control unit activates a high-repetition-rate X-ray pulse source to irradiate the target area of ​​the insulator of the line under test. The control unit activates the solar-blind ultraviolet photosensitive detection unit immediately after the pulse output of the high-repetition-rate X-ray pulse source ends, and the detection frequency is consistent with the X-ray pulse repetition frequency. By starting the switch counter through the execution control unit and keeping it consistent with the working time of the repetition rate X-ray pulse source, the frequency of the discharge light pulse in the X-ray pulse interval time Δt is obtained and denoted as n. The ultrasonic ranging unit is activated by the execution control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source to obtain the ultrasonic ranging value L in the X-ray pulse interval time Δt. The information calculation unit is activated by the execution control unit and kept in sync with the working time of the high-repetition-rate X-ray pulse source. The excitation intensity S of the discharge photons at time t is calculated. Based on the calculation result of the excitation intensity S of the discharge photons, the information calculation unit gives a graded evaluation result and obtains the discharge state of the insulator of the line under test.

7. The active detection method for discharge defects in line insulators according to claim 6, wherein: The control unit activates a high-repetition-rate X-ray pulse source to irradiate the target area of ​​the insulator of the line under test, with the cumulative X-ray dose not exceeding 10 millisieverts.

8. The active detection method for discharge defects in line insulators according to claim 6, wherein: The excitation intensity S of the discharge photons at time t is calculated using the following formula: In the formula, n(t) is the frequency of the X-ray discharge light pulse at time t, n0 is the average discharge frequency of the background light pulse when no X-ray is applied within time T, L(t) is the ultrasonic ranging value at time t, R is the controllable dose of a single pulse of X-ray from the repetitive X-ray pulse source, and θ is the effective detection angle of the solar-blind ultraviolet photosensitive detection unit.

9. The active detection method for discharge defects in line insulators according to claim 6, wherein: The information calculation unit provides graded evaluation results including normal, attention, tracking, early warning, and alarm.

10. The active detection method for discharge defects in line insulators according to claim 8 or 9, wherein: The information calculation unit provides a graded evaluation result based on the calculation result of the discharge photon excitation intensity S, including: Set a valid test value m; Input data S(t i ), in response to S(t i )≤0, output the grading evaluation result as normal; In response to S(t i )>0, the data S(t i ) is verified whether it is valid; in response to |S(t i )-S(t i-1 )|≤m, it is confirmed that the data S(t i ) is valid, and the next evaluation process is entered. Response to S(t) i If a ≤ a1, the output classification assessment result is "concerned"; responding to a1 <S(t i If a ≤ a2, the output hierarchical evaluation result is tracking; the response is a2. <S(t i If a ≤ a3, the output classification assessment result is a warning; the response is a3. <S(t i The output of the graded assessment result is an alarm; Where i is a positive integer, and a1, a2 and a3 are state thresholds.

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