Method and system for detecting arc extinguishing capability of a handcart circuit breaker based on oscillating wave response

Abstract

The application discloses a handcart circuit breaker arc extinguishing capacity detection method and system based on oscillating wave response, relates to the technical field of equipment state detection, and comprises the following steps: obtaining a handcart circuit breaker fracture connection state in a test position or a maintenance position and a breaking state, and establishing a fracture external coupling interference reference corresponding to a to-be-detected fracture; applying a decay oscillating voltage for simulating a post-breaking decay oscillating voltage to the to-be-detected fracture, determining voltage responses and discharge pulse response signals on both sides of the fracture; combining a half perimeter boundary, a voltage decay envelope and the fracture external coupling interference reference, separating fracture responses and extracting a withstand recovery characteristic in each oscillating half cycle; determining a fracture medium recovery state according to the withstand recovery characteristic, and outputting an arc extinguishing capacity detection result. The application can identify insufficient fracture medium recovery and potential reignition risks under non-actual high-current breaking conditions.

Description

Technical Field

[0001] This invention relates to the field of equipment condition monitoring technology, and more specifically, to a method and system for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response. Background Technology

[0002] In existing technologies, the operating status of handcart circuit breakers during maintenance or routine testing is typically evaluated through mechanical characteristic testing, circuit resistance testing, insulation resistance testing, power frequency withstand voltage testing, vacuum testing, or partial discharge testing. For example, mechanical characteristic testing is mainly used to determine whether the opening and closing time, travel, and speed are abnormal, while vacuum or withstand voltage testing is mainly used to determine whether the insulation condition of the arc-extinguishing chamber meets the requirements. Although the above testing methods can reflect whether there are obvious defects in the operating mechanism, conductive circuit, or insulation performance, their testing objects are mostly static or single performance indicators, and cannot directly reproduce the dynamic dielectric recovery process when the circuit breaker contacts withstand the recovery voltage after breaking. Therefore, when the handcart circuit breaker is in a test or maintenance position and a real high-current breaking test cannot be performed, the existing testing results are difficult to directly reflect whether the arc-extinguishing capability of the contacts has degraded.

[0003] Furthermore, while oscillating wave detection technology has been used to detect insulation defects and partial discharges in equipment such as cables, transformers, and switchgear, this type of detection typically focuses on the presence of partial discharge pulses in the tested equipment, rather than the withstand recovery process of the circuit breaker's break point under damped oscillating voltage. For circuit breakers inside cabinets, the detection signal not only includes the discharge pulse response signal that may be generated by the break point itself, but also the external coupling response signal formed by the test leads, cabinet grounding structure, adjacent phase conductors, and residual coupling on the busbar side and cable side. If judgment is based solely on the presence of high-frequency pulses or voltage anomalies, it is easy to mistake the external coupling response signal for a break point discharge, or to fail to distinguish between a true break point discharge and ordinary partial discharge.

[0004] The above-disclosed technical solutions have at least the following technical problems: When the existing handcart circuit breaker is in the test position or maintenance position, it is difficult to distinguish the response of the break point itself from the coupling response signal inside and outside the cabinet by using repeatable recovery voltage stress without conducting a real high current breaking test, and further evaluate the dielectric recovery state of the break point under the action of damped oscillating voltage, which makes it difficult to identify the arc extinguishing capability degradation in a timely and repeatable manner. Summary of the Invention

[0005] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide a method and system for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response. By establishing a benchmark for external coupling interference corresponding to the test break point and combining it with the half-cycle withstand recovery characteristics under damped oscillation voltage to identify the dielectric recovery state of the break point, the present invention addresses the problem that existing handcart circuit breakers are difficult to evaluate the degradation of arc-extinguishing capability and potential reignition risk in non-real breaking conditions during testing or maintenance.

[0006] To achieve the above objectives, the present invention provides the following technical solution: On the one hand, the arc-extinguishing capability detection method for a handcart circuit breaker based on oscillating wave response includes the following steps: acquiring the connection status of the circuit breaker's break point in the test or maintenance position and in the open state, and establishing an external coupling interference reference for the break point to be tested; applying a damped oscillating voltage to the break point to simulate the break point recovery voltage after the circuit breaker is opened, and simultaneously acquiring voltage signals and high-frequency pulse signals on both sides of the break point to be tested; determining the boundary of the oscillation half-cycle based on the effective zero-crossing point or polarity reversal point of the damped oscillating voltage, extracting the voltage attenuation envelope based on the voltage signal, and separating the break point response from the voltage signal and high-frequency pulse signal in combination with the external coupling interference reference; extracting the dielectric withstand recovery characteristics of the break point to be tested in each oscillation half-cycle based on the separated break point response; determining the dielectric recovery state of the break point to be tested under the action of the damped oscillating voltage based on the dielectric withstand recovery characteristics, and outputting the corresponding arc-extinguishing capability detection result.

[0007] In a preferred embodiment, obtaining the disconnection status of the circuit breaker in the test or maintenance position and in the open state includes: obtaining the operating condition information of the circuit breaker; confirming that the circuit breaker meets the preset safety isolation detection conditions based on the operating condition information; connecting the detection device to the terminals on both sides of the disconnection of the phase to be tested and using the cabinet grounding terminal as the reference terminal, applying a low-voltage detection signal to the disconnection to be tested, and collecting the coupling response signals of the terminals on both sides of the disconnection relative to the preset reference terminal; identifying the phase to be tested based on the coupling response signals; and determining the disconnection status when the electrical isolation status meets the preset detection requirements.

[0008] In a preferred embodiment, establishing the external coupling interference reference corresponding to the fracture surface under test includes: after the fracture surface under test is connected to the detection circuit, applying a low-voltage identification signal to both sides of the fracture surface under test, collecting the coupling response signals of the terminals on both sides of the fracture surface relative to a preset reference end, and forming a static coupling reference; applying a detection voltage signal lower than the corona initiation voltage to the fracture surface under test, collecting a background response signal, and forming a non-discharge oscillation reference when the response signal is normal; collecting the coupling response signal of the reference end under the condition that the detection conditions remain unchanged; associating and storing the static coupling reference, the non-discharge oscillation reference, and the coupling response signal of the reference end with the current fracture surface connection state to form an external coupling interference reference for the fracture surface.

[0009] In a preferred embodiment, applying a damped oscillating voltage to the test break to simulate the break recovery voltage after the circuit breaker is broken, and simultaneously acquiring voltage signals and high-frequency pulse signals on both sides of the test break, includes: generating an oscillation constraint parameter set based on the break withstand correlation information of the circuit breaker under test; controlling the charging of the energy storage capacitor based on the oscillation constraint parameter set, and triggering a damped oscillation circuit composed of the energy storage capacitor, the oscillating inductor, and the equivalent capacitance on both sides of the test break after the detection circuit meets the access conditions; and acquiring voltage signals and high-frequency pulse signals on both sides of the test break according to a unified sampling clock during the application of the damped oscillation voltage.

[0010] In a preferred embodiment, the voltage decay envelope is formed by fitting the peak voltage of the half-cycle that avoids the voltage change interval within each effective oscillation half-cycle; the decay coefficient of the decaying oscillation voltage is determined by fitting the peak voltage of multiple effective oscillation half-cycles that are not affected by voltage change intervals and their occurrence times.

[0011] In a preferred embodiment, the step of extracting the voltage decay envelope based on the voltage signal and separating the test fracture response from the voltage signal and high-frequency pulse signal in conjunction with the external coupling interference reference of the fracture surface includes: correcting the voltage signals on both sides of the fracture surface under test and dividing the oscillation half-cycle according to the effective zero crossing point or polarity reversal point; extracting the half-cycle peak voltage in each half-cycle to avoid instantaneous disturbances and forming a voltage decay envelope; mapping the high-frequency pulse signal and voltage change characteristics to the corresponding half-cycle according to the occurrence time to determine the instantaneous fracture voltage and half-cycle peak voltage; eliminating high-frequency pulse signals that match the external coupling characteristics and have no synchronous voltage change according to the external coupling interference reference of the fracture surface; determining the high-frequency pulse signals and corresponding voltage changes that do not match the external coupling characteristics, are located in the effective half-cycle, and satisfy the time sequence correspondence with the voltage change as candidate responses, and merging them to obtain the test fracture response.

[0012] In a preferred embodiment, the step of extracting the medium tolerance recovery characteristics of the fracture surface under test in each oscillation half-cycle includes: converting the response of the fracture surface under test into a half-cycle tolerance state sequence according to the oscillation half-cycle. Based on the sequence of oscillation half-cycles, determine the oscillation half-cycle in which the response of the tested fracture surface first appears and the corresponding first response voltage, and identify the response duration interval and recovery inflection point; combined with the voltage decay envelope, determine the fading or prolongation relationship of the fracture surface response with voltage decay, and generate the dielectric tolerance recovery characteristics.

[0013] In a preferred embodiment, determining the oscillation half-cycle in which the test fracture response first appears and the corresponding first response voltage according to the order of the oscillation half-cycles includes: finding the first oscillation half-cycle that transitions from a non-response state to a response state based on the half-cycle tolerance state sequence; determining the earliest test fracture response within that oscillation half-cycle, and determining the first response voltage based on the instantaneous fracture voltage corresponding to its occurrence time, or the most recent effective voltage before the voltage change.

[0014] In a preferred embodiment, determining the dielectric recovery state of the test break under damped oscillation voltage based on dielectric resilience recovery characteristics includes: constructing a half-cycle resilience state sequence of the test break based on dielectric resilience recovery characteristics; determining a dielectric recovery state judgment criterion based on the equipment parameters or historical data of the test trolley circuit breaker; and comparing the half-cycle resilience state sequence with the dielectric recovery state judgment criterion to determine the dielectric recovery state of the test break.

[0015] On the other hand, the arc-extinguishing capability detection system for a handcart circuit breaker based on oscillating wave response includes the following modules: Connection Status Identification Module: used to acquire the connection status of the handcart circuit breaker in the test or maintenance position and in the open state, and establish an external coupling interference reference for the connection to be tested; Response Acquisition Module: used to apply a damped oscillating voltage to the connection to be tested to simulate the recovery voltage of the connection after the circuit breaker is opened, and simultaneously acquire voltage signals and high-frequency pulse signals on both sides of the connection to be tested; Connection Response Separation Module: used to determine the boundary of the oscillation half-cycle based on the effective zero-crossing point or polarity reversal point of the damped oscillating voltage, extract the voltage attenuation envelope based on the voltage signal, and separate the response of the connection to be tested from the voltage signal and high-frequency pulse signal in combination with the external coupling interference reference; Feature Extraction Module: used to extract the dielectric withstand recovery characteristics of the connection to be tested in each oscillation half-cycle based on the separated response of the connection to be tested; Arc-extinguishing Capability Determination Module: used to determine the dielectric recovery state of the connection to be tested under the action of the damped oscillating voltage based on the dielectric withstand recovery characteristics, and output the corresponding arc-extinguishing capability detection result.

[0016] The technical effects and advantages of this invention, which relates to a method and system for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response, are as follows: This invention establishes an external coupling interference reference corresponding to the connected state of the circuit breaker under test when the circuit breaker is in the test or maintenance position and open. A damped oscillation voltage is applied to the circuit breaker to simulate the damped oscillation voltage after interruption. The collected voltage response and discharge pulse response signals are separated and analyzed according to the oscillation half-cycle. This allows for the differentiation between external coupling response signals generated by test leads, adjacent phase conductors, and grounding structures within the cabinet and the circuit breaker's own response, avoiding indirect judgments of arc-extinguishing capability based solely on high-frequency pulses or withstand voltage results. By extracting the withstand recovery characteristics of the circuit breaker within each oscillation half-cycle, this invention can identify insufficient dielectric recovery, continuous discharge, and potential reignition risks without conducting actual high-current breaking tests. This makes the arc-extinguishing capability test results of the circuit breaker more targeted, repeatable, and applicable to on-site maintenance. Attached Figure Description

[0017] Figure 1 This is a flowchart illustrating the arc-extinguishing capability detection method for a handcart circuit breaker based on oscillating wave response according to the present invention. Figure 2 This is a schematic diagram of the arc-extinguishing capability detection system for handcart circuit breakers based on oscillation wave response according to the present invention. Figure 3 This is a schematic diagram of the electrical principle of a circuit breaker arc extinguishing capability testing system for handcarts. Detailed Implementation

[0018] 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, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] Example 1, Figure 1 The present invention provides a method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response, comprising the following steps: S1, obtain the connection status of the circuit breaker of the handcart in the test position or maintenance position and in the open state, and establish the external coupling interference reference of the circuit breaker corresponding to the circuit breaker to be tested. In this embodiment, the break-in connection status is used to characterize whether the detection device has been correctly connected to the break-in to be tested, and the external coupling environment of the break-in to be tested under the current cabinet position, phase, end-side connection, and grounding isolation conditions. The break-in connection status includes the truck position status, circuit breaker opening and closing status, phase to be tested, connection relationship of terminals on both sides of the break-in, non-phase testing status, and grounding isolation status.

[0020] The acquisition of the disconnection status of the circuit breaker of the handcart in the test position or maintenance position and in the open state includes: Before testing, read the operating condition information of the handcart circuit breaker. The operating condition information includes the auxiliary contacts of the handcart position, the auxiliary contacts for opening and closing, the auxiliary contacts of the grounding switch, and the secondary connection status. Confirm that the handcart circuit breaker is in the test position or maintenance position, the main contacts are in the open state, and the side under test is not short-circuited by the grounding switch or external wiring. Connect the oscillation voltage output terminal and voltage response acquisition terminal of the detection device to the two terminals on both sides of the phase break point under test, take the cabinet grounding terminal as the reference terminal, and identify the phase under test, the moving contact side terminal and the stationary contact side terminal through the low voltage identification signal. The detection device collects the low-voltage coupling response signals of the terminals on both sides of the test break relative to a preset reference terminal, and obtains the low-voltage response amplitude, response delay and channel polarity relationship; wherein, the preset reference terminal includes at least one of the cabinet grounding terminal, adjacent phase terminal and non-test side terminal; When the identification result meets the preset detection requirements, the connection status of the break point to be tested is determined; the preset detection requirements include that the phases to be tested are consistent, there is no low-voltage conduction response on both sides of the break point, the grounding switch status on the side to be tested meets the detection conditions, the non-tested phases are in isolation or specified grounding status, and the low-voltage coupling response signal is consistent with the wiring relationship.

[0021] For example, for a trolley-type vacuum circuit breaker in a 10kV medium-voltage switchgear, after the circuit breaker is moved from the working position to the test position, the detection device first reads the auxiliary contact of the trolley position to confirm that the trolley has not made working contact with the primary plug of the running bus; reads the auxiliary contact of the circuit breaker tripping to confirm that all three-phase main contacts are in the tripping state; and reads the auxiliary contact of the grounding switch to confirm that the side under test has not been short-circuited by grounding.

[0022] When the A-phase break is taken as the object under test, the oscillation wave output terminal is connected to one side of the A-phase break terminal, and the response acquisition terminal is connected to the other side of the A-phase break terminal, while the cabinet grounding terminal is used as the reference terminal. The detection device applies a low-voltage identification signal to both sides of the A-phase break and collects the response amplitude and response delay of the terminals on both sides of the A-phase break to the cabinet grounding terminal, the B-phase terminal, the C-phase terminal, and the non-tested terminals, respectively. If there is no continuity response between the two sides of the A-phase break, and the coupling response signal of the terminals on both sides of the A-phase break is consistent with the preset wiring relationship, then the current connected object is confirmed as the A-phase break, and its break connection status is recorded.

[0023] Furthermore, establishing the external coupling interference reference corresponding to the fracture surface to be tested includes: After the test circuit is actually connected to the fracture point under test, a low-voltage identification signal is applied to both sides of the fracture point under test, and the coupling response signals of the terminals on both sides of the fracture point under test to the cabinet grounding terminal, adjacent phase terminals and non-test side terminals are collected to form a static coupling reference; the static coupling reference includes at least the response amplitude, response delay, channel polarity relationship and amplitude ratio between channels of each acquisition channel; A low-amplitude decaying oscillating voltage is applied to the circuit breaker under test, and the corresponding voltage decay response, high-frequency pulse background response, and inter-channel coupling response signals are collected. The initial peak value of the low-amplitude decaying oscillating voltage is lower than the initial peak value of the oscillation voltage in the formal testing stage, and also lower than the discharge initiation reference voltage of the circuit breaker under test, which is determined based on the rated voltage level, break spacing, factory withstand voltage record, historical qualified test record, or normal break withstand record of the same type of circuit breaker. When no baseline abnormal pulse appears in the high-frequency pulse background response, the voltage decay response, high-frequency pulse background response, and inter-channel coupling response signal are determined as the non-discharge oscillation reference. While keeping the test lead arrangement, grounding point, non-test phase processing method and acquisition channel unchanged, low-amplitude oscillation acquisition is performed on adjacent non-test phases or equivalent unloaded terminals to obtain the coupling response signal of the adjacent phase reference terminal; The coupling response signals of the static coupling reference, the non-discharge oscillation reference, and the adjacent phase reference terminal are bound to the phase, end-side connection relationship, handcart position status, grounding isolation status, non-test phase status, and test channel number of the fracture under test to generate the fracture external coupling interference reference corresponding to the fracture under test. When an abnormal baseline pulse appears in the high-frequency pulse background response, the starting amplitude of the low-amplitude attenuated oscillation voltage is reduced and the data is re-acquired; if an abnormal baseline pulse still appears after reducing the amplitude to the lowest baseline acquisition value allowed by the detection device, the establishment of the external coupling interference reference of the fracture surface is terminated, and the fracture surface under test is recorded as an abnormal discharge state in the baseline stage.

[0024] By following the steps above, the connection object, connection direction, grounding isolation status, and external coupling environment of the break under test can be identified before formal testing, and a reference for external coupling interference corresponding to the current test setup can be established. This allows for the differentiation between the external coupling response signals caused by test leads, cabinet structure, adjacent phase conductors, or the background of the acquisition channel and the response of the break under test itself when applying the damped oscillation voltage, thus avoiding misinterpreting external coupling pulses as abnormal dielectric recovery at the break.

[0025] It should be noted that this invention uses baseline abnormal pulse screening conditions to determine whether the current low-amplitude oscillation acquisition can be used as a non-discharge oscillation benchmark: Let q be the high-frequency pulse that appears on channel c during baseline acquisition, and let its amplitude be... The voltage change on both sides of the break near the corresponding time is The corresponding half-cycle peak voltage is The high-frequency pulse is recorded as a baseline abnormal pulse when the following conditions are met simultaneously:

[0026]

[0027] in, The background pulse amplitude statistics for channel c in low-amplitude baseline acquisition are taken as the median of the amplitude in the interval where there is no obvious pulse in the corresponding acquisition channel. The background fluctuation of channel c is (the median absolute deviation or standard deviation of the background amplitude of the corresponding acquisition channel). The background exceeds the proportion. The voltage surge exceedance ratio. This represents the background fluctuation of voltage abrupt changes in the voltage acquisition channel during the non-discharge region. The voltage surge ratio during the low-amplitude oscillation phase is determined based on the baseline data collected from qualified fracture surfaces of the same model, the noise level of the detection device, and the permissible false alarm level.

[0028] S2, apply a damped oscillating voltage to the test break to simulate the break recovery voltage after the circuit breaker is broken, and simultaneously collect voltage signals and high-frequency pulse signals on both sides of the test break; In this embodiment, the damped oscillating voltage is not used to replace a real high-current breaking test. Instead, it is used to apply a detection voltage stress to the test break point under the condition that the circuit breaker is in the test or maintenance position and is open. This stress has a similar polarity change and amplitude decay pattern to the recovery voltage of the break point after the circuit breaker is broken, thereby obtaining detection data related to the dielectric recovery state of the break point. The damped oscillating voltage has continuously alternating voltage polarities, a gradually decaying peak envelope, and identifiable oscillation half-cycle boundaries, so that the test break point is subjected to recovery voltage stresses of different amplitudes and polarities sequentially within continuous oscillation half-cycles.

[0029] The determination of the voltage response and discharge response on both sides of the fracture surface to be tested includes: The detection device includes a charging unit, an energy storage capacitor, an oscillating inductor, a current-limiting protection element, a trigger switch, and a response acquisition channel. The response acquisition channel includes a voltage acquisition channel for acquiring voltage signals across the test fracture surface and a high-frequency pulse acquisition channel for acquiring high-frequency pulse signals.

[0030] Before testing, obtain the break-point withstand capability correlation information of the circuit breaker under test. This correlation information includes at least one of the following: rated voltage level, break-point spacing, factory withstand voltage record, historical test record, or normal break-point withstand capability record of the same model circuit breaker. Based on this correlation information, generate a set of oscillation constraint parameters for this test. This set of oscillation constraint parameters includes the initial peak value of the oscillation voltage, the oscillation frequency range, the number of effective half-cycles, and the allowable decay time range.

[0031] Specifically, the initial peak value of the oscillation voltage is used to limit the initial detection intensity applied to both sides of the fracture surface under test, avoiding insufficient defect excitation due to excessively low detection voltage, and avoiding damage to the fracture surface due to excessively high detection voltage; the oscillation frequency range is used to limit the rate of change of the decaying oscillation voltage, so that it can reflect the withstand state of the fracture surface during rapid voltage changes; the effective number of detection half cycles is used to limit the range of oscillation half cycles participating in the judgment of medium withstand recovery; the allowable decay time range is used to determine whether the decaying oscillation process meets the requirements of this test.

[0032] After generating the oscillation constraint parameter set, the charging unit is controlled to charge the energy storage capacitor. When the detection circuit meets the access conditions, the trigger switch is controlled to close, causing the energy storage capacitor, the oscillating inductor, and the equivalent capacitance on both sides of the test break to form a damped oscillation circuit, thereby generating a damped oscillation voltage on both sides of the test break. The access conditions include the test break being in an open state, the detection circuit being connected, the acquisition channel being in an effective sampling state, and the protection circuit not triggering abnormal blocking.

[0033] During the application of the damped oscillation voltage, voltage signals and high-frequency pulse signals are synchronously acquired at both ends of the fracture surface under test according to a unified sampling clock. The voltage signals are used to characterize the actual voltage change process on both sides of the fracture surface under test, and the high-frequency pulse signals are used to characterize the rapid pulse disturbances that occur during the detection process. It should be noted that in this step, the acquired high-frequency pulse signals are only the raw acquisition signals and are not directly equivalent to the discharge response of the fracture surface under test; whether it belongs to the fracture response generated by the fracture surface under test itself needs to be separated and confirmed in subsequent steps by combining the oscillation half-cycle boundary, voltage attenuation envelope, and external coupling interference reference of the fracture surface.

[0034] The damped oscillation voltage is specifically:

[0035]

[0036] in, The damped oscillating voltage on both sides of the fracture surface under test. This is the initial voltage peak value. The attenuation coefficient is... The oscillation frequency is... For the initial phase, For oscillating inductors, For energy storage capacitors, The equivalent capacitance formed by the two sides of the fracture and the wiring under test.

[0037] In this embodiment, Instead of being pre-defined as a fixed constant, it is determined based on the measured voltage attenuation envelope on both sides of the fracture surface under test. Specifically, within each effective oscillation half-cycle, the peak voltage of the half-cycle is extracted, avoiding the instantaneous disturbance interval corresponding to the discharge mutation. and the time of its occurrence And determined according to the following relationship:

[0038] The detection device selects multiple effective oscillation half-cycles unaffected by sudden discharge changes at the fracture surface, performs linear fitting, and determines the negative of the slope of the fitted line as... When the number of effective half-cycles is insufficient for linear fitting, the calculation is based on the peak voltage of the two undisturbed half-cycles:

[0039] in, , These are the peak voltages of the i-th and j-th undisturbed effective oscillation half-cycles, respectively. , These represent the times when the corresponding peak occurs, and j>i.

[0040] S3. Determine the oscillation half-cycle boundary based on the effective zero-crossing point or polarity reversal point of the damped oscillation voltage, extract the voltage attenuation envelope based on the voltage signal, and combine the external coupling interference reference of the fracture surface to separate the response of the fracture surface under test from the voltage signal and the high-frequency pulse signal. In this embodiment, the response of the tested fracture refers to the response generated by the fracture itself, determined from the voltage signals and high-frequency pulse signals collected from both sides of the fracture after the applied damped oscillation voltage, excluding external coupling response signals formed by test leads, cabinet grounding structure, adjacent phase conductors, residual coupling on the busbar side, and residual coupling on the cable side. The tested fracture response includes the high-frequency pulse response generated by the fracture's own discharge, voltage dips in the voltage difference across the fracture, waveform inflection points or sudden changes in voltage change rate, and the corresponding oscillation half-cycle, instantaneous fracture voltage, and half-cycle peak voltage.

[0041] The oscillation half-cycle boundary is determined based on the effective zero-crossing point or polarity reversal point of the damped oscillation voltage. The voltage attenuation envelope is extracted from the voltage signal. Combined with the external coupling interference reference of the fracture surface, the response of the fracture surface under test is separated from the voltage signal and the high-frequency pulse signal, including: The voltage signals on both sides of the measured fracture are corrected to remove DC bias and zero drift of the acquisition channel, and a reference oscillation voltage signal for half-cycle division is obtained. Using the triggering moment when the decaying oscillation voltage begins to be applied as the starting reference moment, candidate zero-crossing points or candidate polarity reversal points are determined based on the moment when the reference oscillation voltage signal changes from positive voltage to negative voltage or from negative voltage to positive voltage. Based on the time interval between adjacent candidate zero-crossing points or candidate polarity reversal points, abnormal candidate points caused by voltage sudden changes, noise spikes, or reflections inside the cabinet are eliminated, and candidate points that satisfy the continuity of the oscillation period are retained as valid zero-crossing points or polarity reversal points. The time interval between two adjacent effective zero crossings or polarity reversal points is defined as an oscillation half-cycle, and the effective zero crossings or polarity reversal points are respectively used as the start and end times of the corresponding oscillation half-cycle. Within each oscillation half-cycle, avoiding the instantaneous disturbance interval corresponding to the voltage change, the maximum absolute value of the voltage difference across the break point within that oscillation half-cycle is extracted as the half-cycle peak voltage of that oscillation half-cycle. Arrange the peak voltages of each half-cycle in chronological order to obtain the voltage decay envelope, which characterizes the gradual change in the amplitude of the decaying oscillation voltage. The high-frequency pulse signals, voltage drops, waveform inflection points, or voltage change rate changes that are collected are mapped to the corresponding oscillation half-cycle according to the time of occurrence, and the instantaneous break voltage and the peak voltage of the half-cycle are determined. The mapped high-frequency pulse signal is compared with the external coupling interference reference of the fracture surface. If the high-frequency pulse signal matches the external coupling response signal in the external coupling interference reference of the fracture surface in terms of the relative position of occurrence within half a cycle, channel transmission relationship, amplitude ratio between channels, or normalized amplitude change trend, and is not accompanied by synchronous abrupt change in voltage difference on both sides of the fracture surface under test, then it is identified as an external coupling response signal and discarded. If the high-frequency pulse signal does not conform to the characteristics of the external coupling response signal, is located within the effective half-cycle interval of the decaying oscillation voltage, and satisfies a preset timing correspondence with the voltage drop, waveform inflection point, or voltage rate change abrupt change in the voltage difference across the test fracture, then the high-frequency pulse signal and its corresponding voltage change are determined as candidate responses of the test fracture. The preset timing correspondence means that the occurrence time of the high-frequency pulse signal and the occurrence time of the voltage drop, waveform inflection point, or voltage rate change abrupt change are within the same preset time window, and both correspond to the same oscillation half-cycle or adjacent sampling positions. The preset time window is determined based on the sampling frequency, acquisition channel delay, pulse duration width, and detection device synchronization error.

[0042] Candidate responses of the test fracture that occur at adjacent times and correspond to the same voltage change within the same oscillation half-cycle are merged to obtain the test fracture response within the corresponding oscillation half-cycle.

[0043] In this embodiment, the response of the fracture surface under test is not directly obtained from any arbitrary high-frequency pulse signal. Instead, it is confirmed by the high-frequency pulse signal after half-cycle mapping, instantaneous voltage correspondence, comparison with external coupling interference reference, and verification by voltage synchronous change. In this way, the response of the fracture surface under test can be distinguished from the coupling of the test lead, adjacent phase coupling, cabinet structure coupling, or background interference of the acquisition channel, reducing misjudgments caused by external interference pulses.

[0044] The process of comparing the mapped high-frequency pulse signal with the external coupling interference reference of the fracture surface is as follows: Let the high-frequency pulse to be determined be p, and its occurrence time be... The oscillation half-cycle in which it occurs is the kth oscillation half-cycle, and the kth oscillation half-cycle is represented as:

[0045] in, For the kth half-cycle of oscillation, Let k be the starting time of the kth half-cycle of oscillation. This represents the end time of the kth half-cycle of oscillation.

[0046] The duration of the kth half-cycle of oscillation is:

[0047] The peak voltage of the kth half-cycle of oscillation is:

[0048] in, Let be the duration of the kth half-cycle of the oscillation. The peak voltage of the k-th half-cycle of oscillation. The voltage signals on both sides of the fracture surface to be tested are shown.

[0049] The relative position of the high-frequency pulse p within its oscillation half-cycle is:

[0050] Let the external coupling pulse in the external coupling interference reference of the fracture be b, and its corresponding reference oscillation half-cycle be:

[0051] The duration of the reference oscillation half-cycle in which the external coupling pulse b is located is:

[0052] The peak voltage of the half-cycle of the reference oscillation where the external coupling pulse b is located is:

[0053] in, This is the reference voltage signal in the external coupling interference reference of the break.

[0054] The relative position of the external coupling pulse b within its reference oscillation half-cycle is:

[0055] Let the pulse amplitude of the high-frequency pulse p to be determined be... The pulse amplitude of the external coupling pulse b is Then the normalized amplitudes of the two based on the voltage decay envelope are respectively:

[0056]

[0057] in, , These are the normalized pulse amplitudes, A positive smoothing term is used to avoid the denominator being zero. , These are the peak voltage of the k-th oscillation half-cycle and the peak voltage of the reference oscillation half-cycle where the external coupling pulse b is located, respectively.

[0058] Let the amplitude vector of the high-frequency pulse p to be determined on the C acquisition channels be:

[0059] The multi-channel amplitude scaling vector of the high-frequency pulse p to be determined is:

[0060] Let the amplitude vector of the external coupling pulse b on the C acquisition channels be:

[0061] Let the multi-channel amplitude scaling vector of the external coupling pulse b be:

[0062] in, Let p be the amplitude vector of the high-frequency pulse to be determined on the C acquisition channels. Let p be the multi-channel amplitude scaling vector of the high-frequency pulse to be determined. Let p be the peak amplitude of the high-frequency pulse to be determined on the c-th acquisition channel. Let be the amplitude vector of the external coupling pulse b across the C acquisition channels. This is the multi-channel amplitude scaling vector of the externally coupled pulse b. Let be the peak amplitude of the external coupling pulse b on the c-th acquisition channel.

[0063] The coupling matching distance between the high-frequency pulse p to be determined and the external coupling pulse b is:

[0064] in, Let p be the matching distance between the high-frequency pulse to be determined and the external coupling pulse b. To determine the relative position of the high-frequency pulse p within its oscillation half-cycle, The relative position of the external coupling pulse b within its reference oscillation half-cycle. The normalized pulse amplitude of the high-frequency pulse p to be determined. The normalized amplitude of the external coupling pulse b. The distance between the high-frequency pulse p to be determined and the externally coupled pulse b is the Euclidean distance in terms of the multi-channel amplitude ratio.

[0065] when When the high-frequency pulse to be determined is not accompanied by a synchronous abrupt change in the voltage difference between the two sides of the fracture surface to be tested, it is determined that the high-frequency pulse p to be determined matches the external coupling response signal in the external coupling interference reference of the fracture surface, and it is identified as the external coupling response signal.

[0066] when When the high-frequency pulse to be determined simultaneously satisfies the amplitude exceedance condition, the effective half-cycle condition, and the voltage change condition on both sides of the break in the break discharge determination conditions, the high-frequency pulse to be determined is identified as a candidate response of the break.

[0067] in, This is the external coupling matching limit, used to determine whether the high-frequency pulse to be judged matches the external coupling response signal in the external coupling interference reference of the fracture surface.

[0068] The process of arranging the peak voltages of each half-cycle in chronological order to obtain the voltage decay envelope characterizing the gradual change in the amplitude of the decaying oscillation voltage includes: The voltage signals on both sides of the measured fracture are corrected to remove DC bias and zero drift of the acquisition channel, and a reference oscillation voltage signal for half-cycle division is obtained. Using the triggering moment when the decaying oscillation voltage begins to be applied as the starting reference moment, candidate zero crossings are determined according to the moment when the reference oscillation voltage signal changes from positive voltage to negative voltage or from negative voltage to positive voltage; Based on the time interval between adjacent candidate zero-crossings, abnormal candidate zero-crossings caused by voltage surges, noise spikes, or reflections within the cabinet are eliminated, and candidate zero-crossings that satisfy the continuity of the oscillation period are retained as valid zero-crossings. Here, satisfying the continuity of the oscillation period means that the deviation between the time interval between adjacent candidate zero-crossings and the time interval between the adjacent half-cycles is within the allowable range. When the time interval corresponding to a candidate zero-crossing is significantly smaller than the time interval between the adjacent half-cycles, and there is no stable polarity conversion process near the candidate zero-crossing, it is determined to be an abnormal candidate zero-crossing caused by noise spikes or discharge surges.

[0069] The time interval between two adjacent valid zero crossings is defined as an oscillation half-cycle, and the valid zero crossings are respectively used as the start and end times of the corresponding oscillation half-cycle; Within each oscillation half-cycle, avoiding the instantaneous disturbance interval corresponding to the voltage change, the maximum absolute value of the voltage difference across the break point within that oscillation half-cycle is extracted as the half-cycle peak voltage of that oscillation half-cycle. Arrange the peak voltages of each half-cycle in chronological order to obtain the voltage decay envelope, which characterizes the gradual change in the amplitude of the decaying oscillation voltage.

[0070] In this embodiment, the voltage decay envelope is not formed directly from all instantaneous points of the original voltage waveform, but rather using the peak voltage of each effective oscillation half-cycle as the envelope point. This avoids the influence of local spikes caused by discharge pulses, sampling noise, or stray coupling within the cabinet on the judgment of the decay trend. The voltage decay envelope is used to determine the voltage stress level corresponding to the response of each fracture, enabling subsequent determination of whether the fracture under test withstands normally under a higher recovery voltage or discharges prematurely under a lower recovery voltage.

[0071] The determination of the candidate response of the fracture surface includes: When the high-frequency pulse to be determined simultaneously meets the amplitude exceedance condition, effective half-cycle condition, voltage synchronous change condition, and external coupling mismatch condition, the high-frequency pulse to be determined is identified as a candidate response of the break.

[0072] In this embodiment, let the high-frequency pulse to be determined be p, and its amplitude be p. The time of appearance is The acquisition channel is c. The high-frequency pulse is determined to meet the break-point discharge determination condition when the following conditions are simultaneously met:

[0073]

[0074]

[0075]

[0076] in, The amplitude of the high-frequency pulse to be determined. This represents the statistical value of the background pulse amplitude in the corresponding acquisition channel of the external coupling interference reference at the fracture surface. Background pulse fluctuation amount, The background exceeds the proportion. This represents the voltage surge across the break near the moment the pulse occurs. This represents the voltage fluctuation ratio. The peak voltage of the k-th half-cycle of oscillation. For the kth effective oscillation half-cycle, The matching distance between the pulse to be determined and the external coupling response signal in the external coupling interference reference of the fracture surface is the distance between the pulse to be determined and the external coupling interference reference. This is the limit for external coupling matching.

[0077] S4. Based on the separated fracture surface response, extract the medium tolerance recovery characteristics of the fracture surface during each oscillation half-cycle. In this embodiment, the dielectric withstand recovery characteristic refers to the feature used to characterize whether the tested fracture surface can maintain dielectric withstandness within each oscillation half-cycle under the action of continuously decaying oscillating voltage, and whether it can regain stable withstandness as the oscillation voltage decays after a fracture response occurs. The dielectric withstand recovery characteristic includes the presence or absence of response in each oscillation half-cycle, the oscillation half-cycle corresponding to the first response, the instantaneous fracture voltage corresponding to the first response, the peak voltage of the half-cycle in which the first response occurs, the number of responses within each half-cycle, the number of half-cycles in which responses occur consecutively, the time interval between adjacent responses, the trend of the response amplitude changing with the voltage decay envelope, and the recovery transition half-cycle from the response state to the no-response state.

[0078] The step of extracting the dielectric tolerance recovery characteristics of the fracture surface under test within each oscillation half-cycle based on the separated fracture surface response includes: For each oscillation half-cycle, determine whether there is a response at the fracture surface to be tested within that oscillation half-cycle, and generate the response presence or absence status for the corresponding half-cycle. When a response to the fracture surface under test is present, record the oscillation half-cycle in which the response to the fracture surface under test is located, the time of occurrence, the corresponding instantaneous fracture voltage, the peak voltage of the half-cycle, the amplitude of the high-frequency pulse, the duration of the high-frequency pulse, and the number of responses within the same half-cycle. Based on the sequence of oscillation half-cycles, determine the oscillation half-cycle in which the first response of the tested fracture surface appears and the corresponding first response voltage. The number of consecutive oscillation half-cycles of the response of the test fracture surface is counted, and the time interval and half-cycle interval between adjacent test fracture surface responses are determined. Based on the voltage decay envelope formed by the peak voltage of each oscillation half-cycle, determine whether the response number, response amplitude, and adjacent response interval of the test fracture change with voltage decay. The recovery transition half-cycle is determined based on the position where the response state transitions to a continuous no-response state; The presence or absence of the response, the first half-cycle of the response, the first response voltage, the number of consecutive half-cycles of the response, the number of responses in each half-cycle, the interval between adjacent responses, the trend of response amplitude change, and the recovery transition half-cycle are collected to form the medium tolerance recovery characteristics of the fracture surface under test in each oscillation half-cycle.

[0079] Further, determining the oscillation half-cycle in which the first response of the tested fracture surface occurs and the corresponding first response voltage according to the order of the oscillation half-cycles includes: According to the start and end times of each oscillation half-cycle, the oscillation half-cycles are numbered sequentially to form a half-cycle sequence; The separated fracture response is mapped to the corresponding oscillation half-cycle according to the occurrence time, and the occurrence time, oscillation half-cycle, and corresponding instantaneous fracture voltage of each fracture response are recorded. According to the order of the half-cycle sequence, determine whether there is a response of the fracture surface to be tested in each half-cycle of oscillation. The oscillation half-cycle in which the first response to the fracture surface under test is defined as the first response half-cycle. When there is only one test fracture response within the first response half-cycle, the instantaneous voltage difference between the two sides of the test fracture corresponding to the moment the test fracture response appears is determined as the first response voltage. When multiple test fracture responses exist within the first response half-cycle, the earliest test fracture response is taken as the first response, and the instantaneous voltage difference between the two sides of the test fracture corresponding to the moment the first response appears is determined as the first response voltage. If the time of occurrence of the first response falls within the voltage drop range, the voltage difference between the two sides of the break corresponding to the nearest valid sampling point before the voltage drop begins shall be taken as the first response voltage. Record the half-cycle number, start and end times, half-cycle peak voltage, and the first response voltage of the first response half-cycle.

[0080] Furthermore, determining the recovery transition half-cycle based on the position where the response state transitions to a continuous no-response state includes: Based on the order of the oscillation half-cycles, determine the oscillation half-cycle in which the response of the test fracture surface last appears; After the last half-cycle of oscillation where the test fracture response occurs, determine whether subsequent half-cycles of oscillation continuously satisfy the stable no-response condition; When no response is found at the test fracture surface for a continuous number of effective oscillation half-cycles, the first oscillation half-cycle in the continuous non-response half-cycles is determined as the recovery transition half-cycle. If no consecutive oscillation half-cycles satisfying the stable no-response condition occur before the end of the effective detection half-cycle, it is determined that there is no recovery transition half-cycle.

[0081] The predetermined quantity is determined based on the number of effective detection half cycles, the decay rate of the decaying oscillation voltage, and historical detection records of qualified fracture surfaces of the same model; when historical statistical samples are lacking, the predetermined quantity shall be no less than two effective oscillation half cycles.

[0082] S5, based on the dielectric withstand recovery characteristics, determines the dielectric recovery state of the test fracture surface under the action of damped oscillation voltage, and outputs the corresponding arc extinguishing capability test result.

[0083] In this embodiment, the dielectric recovery state refers to whether the dielectric of the fracture surface under test can maintain its tolerance during each half-cycle of oscillation when subjected to a fracture recovery voltage simulated by a damped oscillation voltage, and whether it can regain stable tolerance as the oscillation voltage decays after the fracture surface under test responds. The dielectric recovery state includes at least one of the following: sufficient recovery state, decreased recovery margin state, insufficient dielectric recovery state, and potential reignition risk state.

[0084] Among them, the fully recovered state refers to the absence of a test fracture response that meets the fracture response judgment conditions within half a week of effective detection; The state of decreased recovery margin refers to the presence of a small amount of response from the test fracture surface, but the response from the test fracture surface disappears rapidly with voltage decay and does not form a continuous half-cycle repeating response. Insufficient dielectric recovery refers to the failure surface under test exhibiting a response when the voltage is lower than the normal withstand reference level, or the failure surface repeatedly exhibiting a response within multiple consecutive oscillation half-cycles. The potential reignition risk state refers to the state in which the test fracture still exhibits a continuous response under the action of damped oscillating voltage, the response interval does not increase, the recovery transition half-cycle is delayed or there is no recovery transition half-cycle.

[0085] The normal withstand reference level is used to characterize the lowest permissible initial response voltage reference value for circuit breakers of the same model or operating class under the same testing and connection conditions. The normal withstand reference level is determined based on the quantile value of the initial response voltage in the normal withstand record of the same model circuit breaker, the converted value of the factory withstand voltage record, or the historical qualified test record of this circuit breaker.

[0086] In this embodiment, determining the dielectric recovery state of the fracture surface under damped oscillation voltage based on the dielectric withstand recovery characteristics includes: Based on the presence or absence of response in each oscillation half-cycle, the initial response voltage, the initial response half-cycle, the number of consecutive response half-cycles, the number of responses in each half-cycle, the interval between adjacent responses, and the recovery transition half-cycle, a half-cycle tolerance state sequence of the fracture surface to be tested is formed. Based on the rated voltage level, break spacing, factory withstand voltage record, historical test record, or normal break withstand record of the circuit breaker under test, determine the normal withstand reference level, continuous response judgment limit and stable recovery judgment requirement. When no fracture response meeting the fracture response determination condition appears in the half-cycle tolerance state sequence within the effective half-cycle, the fracture surface under test is determined to be in a fully recovered state. When the test fracture response exists in the half-cycle withstand state sequence, but the test fracture response only appears in the initial high voltage half-cycle or a few discrete half-cycles, and the test fracture response does not appear again in the subsequent consecutive half-cycles that meet the stable recovery judgment requirements, the test fracture is determined to be in a state of decreasing recovery margin. When the initial response voltage is lower than the normal tolerance reference level, or the number of consecutive half-cycles reaches the consecutive response judgment limit, or the response of the test fracture recurs after the voltage decay envelope has been reduced, the test fracture is determined to be in a state of insufficient dielectric recovery. When the medium is in a state of insufficient recovery, and the adjacent response interval does not increase with the decay of the oscillation voltage, the number of responses does not decrease with the decay of the oscillation voltage, or there is no recovery transition half-cycle from the response state to the non-response state, the test fracture is determined to be in a state of potential reignition risk.

[0087] Furthermore, the arc-extinguishing capability detection result corresponding to the output includes: Output the phase of the fracture point under test, the connection relationship between the ends, the position status of the handcart, and the detection access status; Output the damped oscillation voltage parameters used in this detection, including the initial amplitude, oscillation frequency, number of effective detection half cycles, and voltage attenuation envelope; Output the response separation result of the fracture surface under test, which includes pulse information identified as an external coupling response signal, pulse information determined as the response of the fracture surface under test, and the corresponding oscillation half-cycle number. The output dielectric tolerance recovery characteristics include the first response half-cycle, the first response voltage, the number of responses in each half-cycle, the number of consecutive response half-cycles, the interval between adjacent responses, and the recovery transition half-cycle. An arc extinguishing capability test conclusion is generated based on the medium recovery status, and the arc extinguishing capability test conclusion includes at least one of the following: normal arc extinguishing capability, decreased arc extinguishing capability, insufficient medium recovery, and potential risk of reignition. When the three-phase break is tested separately, the arc extinguishing capability comparison results of the three-phase break are output, and the phases with lower initial response voltage, more continuous response half-cycles, or later recovery transition half-cycles are identified as the key phases for review.

[0088] The determination methods for the normal tolerance reference level, continuous discharge judgment limit, and stable recovery judgment requirement are as follows: The normal withstand reference level is used to characterize the lowest allowable initial response voltage reference value of a handcart circuit breaker of the same type or operating class under the same detection access conditions; When there are normal break withstand records of the same model, rated voltage level, cabinet type and detection access conditions, the normal withstand reference level is determined according to the first response voltage quantile in the normal break withstand record. When the normal withstand voltage record of the same model is insufficient, the normal withstand voltage reference level shall be determined by combining the converted value of the factory withstand voltage record, the historical qualified test record of this circuit breaker and the on-site allowable test voltage. When the test waveform corresponding to the factory withstand voltage record and the historical test record is different from the current damped oscillation voltage, the corresponding withstand voltage is converted to the half-cycle peak voltage of the current test and then used to determine the normal withstand reference level. The continuous response judgment limit is used to determine whether the fracture surface under test repeatedly loses its tolerance within multiple consecutive oscillation half-cycles. The continuous response judgment limit is determined based on the number of consecutive response half-cycles, the number of effective detection half-cycles, and the sampling reliability of the detection device in the historical test records of normal fracture surfaces of the same model; when historical statistical samples are lacking, the continuous response judgment limit is no less than two consecutive effective oscillation half-cycles. The stability recovery determination requirement is used to determine whether the test fault has returned to a stable, unresponsive state after a test fault response occurs. The stability recovery determination requirement includes: no test fault response occurs within a consecutive effective oscillation half-cycle for no less than a predetermined number of half-cycles, and no voltage drop, waveform inflection point, or voltage rate change change related to the test fault response occurs within the corresponding half-cycle.

[0089] Through the above embodiments, this invention does not simply determine whether the tested break point breaks down under a fixed voltage. Instead, under the action of a damped oscillating voltage simulating the recovery voltage of the circuit breaker after it has been opened, it correlates the voltage signals on both sides of the tested break point, the high-frequency pulse signal, the boundary of the oscillation half-cycle, the voltage attenuation envelope, and the external coupling interference reference of the break point. This allows for the separation of the tested break point's own response and further extraction of the dielectric withstand recovery characteristics within each oscillation half-cycle. Therefore, it can determine whether the tested break point possesses stable dielectric recovery capability under continuous recovery voltage, thereby outputting a detection result related to the arc-extinguishing capability of the handcart circuit breaker.

[0090] Example 2, Figure 2This invention provides a detection system for the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response, comprising: Access Status Identification Module: Used to obtain the connection status of the circuit breaker of the handcart in the test position or maintenance position and in the open state, and to establish the external coupling interference benchmark of the circuit breaker to be tested. Response acquisition module: used to apply a damped oscillating voltage to the test break to simulate the break recovery voltage after the circuit breaker is broken, and to simultaneously acquire the voltage signals and high-frequency pulse signals on both sides of the test break; The fracture response separation module is used to determine the oscillation half-cycle boundary based on the effective zero-crossing point or polarity reversal point of the damped oscillation voltage, extract the voltage decay envelope based on the voltage signal, and separate the fracture response under test from the voltage signal and the high-frequency pulse signal by combining the external coupling interference reference of the fracture. Feature extraction module: used to extract the medium tolerance recovery characteristics of the fracture surface under test in each oscillation half-cycle based on the separated fracture surface response; Arc extinguishing capability determination module: It is used to determine the dielectric recovery state of the test fracture under damped oscillation voltage based on the dielectric withstand recovery characteristics, and output the corresponding arc extinguishing capability test results.

[0091] Figure 3 This is a schematic diagram of the electrical principle of a circuit breaker arc-extinguishing capability testing system provided in an embodiment of the present invention. The testing system includes a circuit breaker under test (break 1), an oscillating inductor (2), an adjustable capacitor bank (3), an energy storage capacitor (4), a high-voltage trigger switch (5), a response acquisition unit (6), a discharge pulse acquisition sensor (7), and a control and acquisition terminal (8). In use, the testing system is connected to both sides of the circuit breaker under test when it is in the open state via two test terminals.

[0092] The system comprises an oscillating inductor 2, an adjustable capacitor bank 3, and an energy storage capacitor 4 to form a damped oscillation circuit. A high-voltage trigger switch 5 controls the energy storage capacitor 4 to release energy into the damped oscillation circuit, creating a damped oscillation voltage on both sides of the tested break to simulate the damped oscillation voltage after a circuit breaker trips. A response acquisition unit 6 is connected to both sides of the tested break to acquire the voltage difference, oscillation half-cycle boundary, half-cycle peak voltage, voltage attenuation envelope, and voltage jumps caused by break discharge. A discharge pulse acquisition sensor 7 is positioned on the return conductor of the detection circuit or near the tested break to acquire the high-frequency discharge pulse response generated by the tested break under the damped oscillation voltage. A control and acquisition terminal 8 is communicatively connected to the response acquisition unit 6 for setting detection parameters, displaying waveforms, analyzing data, and outputting detection results.

[0093] During testing, first confirm that the circuit breaker is in the test or maintenance position and in the open state. After the test circuit is actually connected to the break point under test, establish an external coupling interference reference for the break point. Then, control the energy storage capacitor 4, oscillating inductor 2, and adjustable capacitor bank 3 through high-voltage trigger switch 5 to form a damped oscillating voltage, so that the break point under test is subjected to recovery voltage stresses of different amplitudes and polarities within a continuous oscillation half-cycle. The response acquisition unit 6 synchronously acquires the voltage response on both sides of the break point, and the discharge pulse acquisition sensor 7 synchronously acquires the discharge pulse response signal. Based on the half-cycle boundary and voltage attenuation envelope of the damped oscillating voltage, combined with the external coupling interference reference for the break point, the detection system separates the response of the break point under test from the acquired signal and extracts the withstand recovery characteristics of the break point under test within each oscillation half-cycle to determine the dielectric recovery state of the break point and output the arc extinguishing capability test result.

[0094] The above formulas are all dimensionless calculations. The formulas are derived from software simulations based on a large amount of collected data to obtain the most recent real-world results. The preset parameters in the formulas are set by those skilled in the art according to the actual situation.

[0095] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented using software, the above embodiments can be implemented, in whole or in part, in the form of a computer program product.

[0096] Those skilled in the art will recognize that the modules and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0097] In addition, the functional modules in the various embodiments of this application can be integrated into one processing module, or each module can exist physically separately, or two or more modules can be integrated into one module.

[0098] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0099] In conclusion, the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response, characterized in that, Includes the following steps: Obtain the connection status of the circuit breaker of the handcart in the test position or maintenance position and in the open state, and establish the external coupling interference reference corresponding to the circuit breaker to be tested. A damped oscillating voltage is applied to the test break to simulate the break recovery voltage after the circuit breaker is broken, and voltage signals and high-frequency pulse signals on both sides of the test break are collected simultaneously. The oscillation half-cycle boundary is determined based on the effective zero-crossing point or polarity reversal point of the damped oscillation voltage. The voltage decay envelope is extracted based on the voltage signal. Combined with the external coupling interference reference of the fracture surface, the response of the fracture surface under test is separated from the voltage signal and the high-frequency pulse signal. Based on the separated fracture surface response, the medium tolerance recovery characteristics of the fracture surface during each oscillation half-cycle are extracted. Based on the dielectric withstand recovery characteristics, the dielectric recovery state of the test fracture surface under damped oscillation voltage is determined, and the corresponding arc extinguishing capability test results are output.

2. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 1, characterized in that, The acquisition of the disconnection status of the circuit breaker of the handcart in the test position or maintenance position and in the open state includes: Obtain the operating condition information of the handcart circuit breaker, and confirm that the handcart circuit breaker meets the preset safety isolation detection conditions based on the operating condition information; Connect the detection device to the terminals on both sides of the phase break under test and use the cabinet grounding terminal as the reference terminal. Apply a low-voltage detection signal to the phase break under test and collect the coupling response signal of the terminals on both sides of the break relative to the preset reference terminal. The phase to be tested is identified based on the coupling response signal. When the electrical isolation state meets the preset detection requirements, the break-in state is determined.

3. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 2, characterized in that, The establishment of the external coupling interference reference corresponding to the fracture surface to be tested includes: After the test break is connected to the detection circuit, a low-voltage identification signal is applied to both sides of the test break, and the coupling response signal of the terminals on both sides of the break relative to the preset reference end is collected to form a static coupling reference. A detection voltage signal lower than the corona initiation voltage is applied to the fracture surface under test, the background response signal is collected, and a non-discharge oscillation reference is formed when the response signal is normal. Under the condition that the detection conditions remain unchanged, the coupling response signal of the reference end is acquired; The coupling response signals of the static coupling reference, the non-discharge oscillation reference, and the reference end are associated and stored with the current break point connection state to form an external coupling interference reference for the break point.

4. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 3, characterized in that, The process involves applying a damped oscillating voltage to the test break to simulate the break recovery voltage after circuit breaker interruption, and simultaneously acquiring voltage signals and high-frequency pulse signals on both sides of the test break, including: An oscillation constraint parameter set is generated based on the fault tolerance correlation information of the circuit breaker under test. The charging of the energy storage capacitor is controlled based on the oscillation constraint parameter set, and the damped oscillation circuit composed of the energy storage capacitor, the oscillation inductor and the equivalent capacitance on both sides of the test break is triggered after the detection circuit meets the access conditions. During the application of the damped oscillation voltage, voltage signals and high-frequency pulse signals on both sides of the test fracture are collected according to a unified sampling clock.

5. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 4, characterized in that, The voltage decay envelope is formed by fitting the peak voltage of the half-cycle that avoids the voltage change interval within each effective oscillation half-cycle. The attenuation coefficient of the damped oscillation voltage is determined by fitting the peak voltage of multiple effective oscillation half-cycles unaffected by voltage sudden changes and their occurrence times.

6. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 5, characterized in that, The step of extracting the voltage attenuation envelope based on the voltage signal, combining it with the external coupling interference reference of the fracture surface, and separating the response of the fracture surface under test from the voltage signal and the high-frequency pulse signal includes: Correct the voltage signals on both sides of the fracture surface under test, and divide the oscillation half-cycle according to the effective zero crossing point or polarity reversal point; Within each half-cycle, avoid instantaneous disturbances to extract the peak voltage of the half-cycle and form a voltage decay envelope; The high-frequency pulse signal and voltage change characteristics are mapped to the corresponding half-cycle according to the time of occurrence to determine the instantaneous break voltage and the half-cycle peak voltage; Based on the external coupling interference benchmark of the fracture surface, high-frequency pulse signals that match the external coupling characteristics and have no synchronous voltage change are eliminated; The high-frequency pulse signal with mismatched external coupling characteristics, located in the effective half-cycle and satisfying the time sequence correspondence with the voltage change, and the corresponding voltage change are identified as candidate responses and combined to obtain the response of the fracture surface to be tested.

7. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 6, characterized in that, The extraction of the dielectric tolerance recovery characteristics of the fracture surface under test during each oscillation half-cycle includes: The response of the fracture surface under test is converted into a half-cycle tolerance state sequence according to the oscillation half-cycle; Based on the sequence of oscillation half-cycles, determine the oscillation half-cycle in which the first response of the test fracture occurs and the corresponding first response voltage, and identify the response duration range and recovery inflection point. By combining the voltage decay envelope, the relationship between the fading and continuing of the fault response with voltage decay is determined, and the dielectric tolerance recovery characteristics are generated.

8. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 7, characterized in that, The determination of the oscillation half-cycle and the corresponding first response voltage of the first occurrence of the response at the tested fracture surface, according to the order of the oscillation half-cycles, includes: Find the first oscillatory half-cycle that transitions from a non-responsive state to a responsive state based on the half-cycle tolerance state sequence; Within the oscillation half-cycle, the earliest occurrence of the test fracture response is determined, and the first response voltage is determined based on the instantaneous fracture voltage corresponding to the time of its occurrence, or the most recent effective voltage before the voltage change.

9. The method for detecting the arc-extinguishing capability of a handcart circuit breaker based on oscillating wave response according to claim 1, characterized in that, The determination of the dielectric recovery state of the fracture surface under damped oscillation voltage based on the dielectric withstand recovery characteristics includes: A half-cycle tolerance state sequence of the fracture surface under test is constructed based on the tolerance recovery characteristics of the medium. The criteria for determining the recovery status of the medium are determined based on the equipment parameters or historical data of the circuit breaker under test. The medium recovery state of the test fracture surface is determined by comparing the half-cycle endurance state sequence with the medium recovery state judgment criteria.

10. A system for detecting the arc-extinguishing capability of a trolley circuit breaker based on oscillating wave response, used to execute the method for detecting the arc-extinguishing capability of a trolley circuit breaker based on oscillating wave response as described in any one of claims 1 to 9, characterized in that, include: Access Status Identification Module: Used to obtain the connection status of the circuit breaker of the handcart in the test position or maintenance position and in the open state, and to establish the external coupling interference benchmark of the circuit breaker to be tested. Response acquisition module: used to apply a damped oscillating voltage to the test break to simulate the break recovery voltage after the circuit breaker is broken, and to simultaneously acquire the voltage signals and high-frequency pulse signals on both sides of the test break; The fracture response separation module is used to determine the oscillation half-cycle boundary based on the effective zero-crossing point or polarity reversal point of the damped oscillation voltage, extract the voltage decay envelope based on the voltage signal, and separate the fracture response under test from the voltage signal and the high-frequency pulse signal by combining the external coupling interference reference of the fracture. Feature extraction module: used to extract the medium tolerance recovery characteristics of the fracture surface under test in each oscillation half-cycle based on the separated fracture surface response; Arc extinguishing capability determination module: It is used to determine the dielectric recovery state of the test fracture under damped oscillation voltage based on the dielectric withstand recovery characteristics, and output the corresponding arc extinguishing capability test results.

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