A method, system and device for detecting the performance of a high-voltage circuit breaker
By collecting electromagnetic wave signals in both the de-energized and energized states of the circuit breaker, and combining time-domain, frequency-domain, and timing analysis, interference signals from the operating mechanism are identified and eliminated, thus solving the detection distortion problem caused by signal overlap and achieving accurate evaluation of the breaking performance of the high-voltage circuit breaker.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- YUNNAN POWER GRID CO LTD ELECTRIC POWER RES INST
- Filing Date
- 2026-04-24
- Publication Date
- 2026-06-23
Smart Images
Figure CN122260099A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of power equipment technology, and in particular to a method, system and equipment for testing the performance of high-voltage circuit breakers to eliminate interference. Background Technology
[0002] High-voltage circuit breakers are key equipment in power systems, playing a vital role in control and protection. Their breaking performance directly affects the safety and stability of the power system.
[0003] However, in practical applications, electromagnetic components in the circuit breaker operating mechanism (such as relays, opening and closing coils, auxiliary switches, etc.) generate radiated electromagnetic waves when they operate. Current technology for testing the breaking performance of circuit breakers typically collects electromagnetic wave signals directly while the circuit breaker is energized. The collected signals may include not only the radiated signals from the arc-extinguishing chamber but also interference signals from the operating mechanism. Because the interfering electromagnetic waves generated by the operating mechanism overlap with the effective electromagnetic waves radiated from the arc-extinguishing chamber, the detection signal is distorted, making it impossible to accurately extract the arc-extinguishing chamber's radiated signals and accurately determine the state of the arc-extinguishing chamber. Summary of the Invention
[0004] Therefore, it is necessary to propose an interference-free high-voltage circuit breaker performance testing method, system, and equipment to address the above problems.
[0005] A method for testing the performance of a high-voltage circuit breaker to remove interference, the method comprising: When the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, the high-voltage circuit breaker operating mechanism is triggered to perform a tripping operation to obtain the first electromagnetic wave signal. When the high-voltage circuit breaker under test is energized and performs a breaking operation, a second electromagnetic wave signal is acquired. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. Multiple time intervals are preset, and the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal is calculated in each time interval to determine the interference interval when the correlation coefficient exceeds a first preset threshold. Fourier transforms are performed on the second electromagnetic wave signal and the first electromagnetic wave signal respectively. The distribution characteristics of their energy in each frequency component are compared, and the frequency bands whose similarity in distribution characteristics exceeds a second preset value are taken as interference frequency bands. The timing sequence of the operation of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test is obtained to determine the theoretical interference time. The interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time are identified as operating mechanism interference signals, and are removed from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The breaking performance of the high-voltage circuit breaker is evaluated based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0006] In the above scheme, before acquiring the first electromagnetic wave signal, the method further includes: The electromagnetic wave signals, duration, and occurrence time of each electromagnetic element generated by the high-voltage circuit breaker operating mechanism during actual operation are collected. The electromagnetic elements in the high-voltage circuit breaker operating mechanism include relays, opening and closing coils, and auxiliary switches. The known operating sequence of each electromagnetic element is determined by the electromagnetic wave signal of each electromagnetic element.
[0007] In the above scheme, removing it from the second electromagnetic wave signal to obtain the electromagnetic radiation signal of the arc-extinguishing chamber specifically includes: The second electromagnetic wave signal is subjected to discrete wavelet transform to obtain transform data at each scale, and the transform data includes wavelet coefficients. Based on the interference range, interference frequency band, and theoretical interference time, determine the wavelet coefficients corresponding to the interference signal of the operating mechanism; The wavelet coefficients corresponding to the interference signal of the operating mechanism are thresholded. Discrete wavelet inverse transform is performed on the thresholded transform data at each scale to obtain the electromagnetic radiation signal of the arc-extinguishing chamber.
[0008] In the above scheme, the thresholding of the wavelet coefficients corresponding to the interference signal of the operating mechanism specifically includes: If the absolute value of the wavelet coefficient is greater than or equal to the scale correlation threshold, then the wavelet coefficient is retained. If the absolute value of the wavelet coefficient is less than the scale correlation threshold, then the wavelet coefficient is set to zero; The formula for calculating the scale-related threshold is: λi=σi
[0009] In the formula, i is the scale number, ni is the length of the wavelet coefficient at the i-th scale, σi is the noise standard deviation estimate of the wavelet coefficient at the i-th scale, and λi is the threshold of the wavelet coefficient at the i-th scale.
[0010] In the above scheme, the noise standard deviation estimate σi of the wavelet coefficients at the i-th scale is determined according to the following formula:
[0011] In the formula, i is the scale index, k is the position index of the wavelet coefficient at the i-th scale, and MAD(·) represents the median of the set of absolute values of all wavelet coefficients. Let be the wavelet coefficient at the k-th position on the i-th scale, and let q be 0.6745. Let be the length of the wavelet coefficients at the i-th scale.
[0012] In the above scheme, the first electromagnetic wave signal and the second electromagnetic wave signal are acquired by a radiated electromagnetic wave sensor, and the operating frequency band of the radiated electromagnetic wave sensor is 0.5 GHz to 2 GHz.
[0013] In the above scheme, evaluating the breaking performance of the high-voltage circuit breaker based on the electromagnetic radiation signal from the arc-extinguishing chamber specifically includes: Acquire reference characteristic data of high-voltage circuit breakers, wherein the reference characteristic data of high-voltage circuit breakers is the characteristic range of electromagnetic radiation signal of the arc-extinguishing chamber of a high-voltage circuit breaker with known qualified breaking performance when performing a breaking operation. The amplitude, number of pulses, energy, spectral characteristics, and occurrence time of the electromagnetic radiation signal from the arc-extinguishing chamber extracted from the high-voltage circuit breaker under test are analyzed to obtain the characteristic data to be tested. The test feature data is compared with the reference feature data; When the test feature data is within the feature range of the reference feature data, the breaking performance of the high-voltage circuit breaker under test is determined to be normal. When the test feature data is not within the feature range of the reference feature data, the breaking performance of the high-voltage circuit breaker under test is determined to be abnormal.
[0014] This application also proposes a high-voltage circuit breaker performance testing system for interference removal, the system comprising: a signal acquisition unit, a time-domain comparison unit, a frequency-domain comparison unit, a timing location unit, an interference removal unit, and a performance evaluation unit; The signal acquisition unit is used to trigger the high-voltage circuit breaker operating mechanism to perform a tripping operation when the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, and to acquire a first electromagnetic wave signal; when the high-voltage circuit breaker under test is energized and performs a tripping operation, it acquires a second electromagnetic wave signal, the second electromagnetic wave signal including the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal; The time-domain comparison unit is used to preset multiple time intervals, calculate the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal in each time interval, and determine the interference interval when the correlation coefficient exceeds a first preset threshold. The frequency domain comparison unit is used to perform Fourier transforms on the second electromagnetic wave signal and the first electromagnetic wave signal respectively, compare the energy distribution characteristics of the two at each frequency, and select the signal with the highest similarity in distribution characteristics. The preset frequency band is used as the interference frequency band; The timing positioning unit is used to acquire the action timing of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test, and to determine the theoretical interference time. The interference elimination unit is used to identify the interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time as operating mechanism interference signals, and to eliminate them from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The performance evaluation unit is used to evaluate the breaking performance of the high-voltage circuit breaker based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0015] This application also proposes a readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the following steps: When the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, the high-voltage circuit breaker operating mechanism is triggered to perform a tripping operation to obtain the first electromagnetic wave signal. When the high-voltage circuit breaker under test is energized and performs a breaking operation, a second electromagnetic wave signal is acquired. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. Multiple time intervals are preset, and the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal is calculated in each time interval to determine the interference interval when the correlation coefficient exceeds a first preset threshold. Fourier transforms are performed on the second electromagnetic wave signal and the first electromagnetic wave signal respectively. The distribution characteristics of their energy in each frequency component are compared, and the frequency bands whose similarity in distribution characteristics exceeds a second preset value are taken as interference frequency bands. The timing sequence of the operation of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test is obtained to determine the theoretical interference time. The interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time are identified as operating mechanism interference signals, and are removed from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The breaking performance of the high-voltage circuit breaker is evaluated based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0016] This application also proposes a computer device, including a memory and a processor, wherein the memory stores a computer program, and the computer program is executed by the processor in the following steps: When the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, the high-voltage circuit breaker operating mechanism is triggered to perform a tripping operation to obtain the first electromagnetic wave signal. When the high-voltage circuit breaker under test is energized and performs a breaking operation, a second electromagnetic wave signal is acquired. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. Multiple time intervals are preset, and the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal is calculated in each time interval to determine the interference interval when the correlation coefficient exceeds a first preset threshold. Fourier transforms are performed on the second electromagnetic wave signal and the first electromagnetic wave signal respectively. The distribution characteristics of their energy in each frequency component are compared, and the frequency bands whose similarity in distribution characteristics exceeds a second preset value are taken as interference frequency bands. The timing sequence of the operation of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test is obtained to determine the theoretical interference time. The interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time are identified as operating mechanism interference signals, and are removed from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The breaking performance of the high-voltage circuit breaker is evaluated based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0017] The present invention provides the following advantages: By collecting first and second electromagnetic wave signals under both energized and de-energized circuit breaker conditions, and utilizing the fundamental difference between the interference signals from the operating mechanism and the different radiation signals from the arc-extinguishing chamber, the present invention calculates the interference interval with a correlation coefficient exceeding the threshold in the time domain, identifies the interference frequency band with similarity exceeding the threshold by comparing energy distribution through Fourier transform in the frequency domain, and determines the theoretical interference time by combining the action sequence of each electromagnetic component of the operating mechanism. Finally, signal components that simultaneously satisfy time-domain correlation, frequency-domain similarity, and timing matching are accurately identified as operating mechanism interference signals and eliminated. This effectively solves the problem of existing technologies failing to accurately extract arc-extinguishing chamber radiation signals due to the mixing of interference signals and valid signals, significantly improving the purity of arc-extinguishing chamber electromagnetic radiation signal extraction and the accuracy of circuit breaker breaking performance detection. Furthermore, this method eliminates the need to disassemble the circuit breaker operating mechanism, providing a reliable technical means for high-voltage circuit breaker condition assessment. Attached Figure Description
[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0019] in: Figure 1 This is a schematic diagram of a high-voltage circuit breaker performance testing method for interference removal in one embodiment; Figure 2 This is a schematic diagram of the operating mechanism simulation test platform in one embodiment; Figure 3 This is a comparison diagram of the no-load tripping signal and the live tripping signal of a 126kV circuit breaker in one embodiment. Figure 3 (a) in the figure is the no-load trip signal collected when the high-voltage circuit is not energized when using a 126kV circuit breaker; Figure 3 (b) in the figure is the live trip signal collected when using a 126kV circuit breaker under energized conditions; Figure 4 This is a comparison diagram of no-load tripping and live tripping signals of a 35kV circuit breaker in one embodiment; Figure 4 (a) in the figure is the no-load trip signal collected when the high-voltage circuit is not energized when using a 35kV circuit breaker; Figure 4 (b) in the figure is the live trip signal collected when using a 35kV circuit breaker under energized conditions. Detailed Implementation
[0020] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 skilled in the art without creative effort are within the scope of protection of the present invention.
[0021] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention; however, it will be apparent to those skilled in the art that the invention may be practiced without one or more of these details; in other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the invention. It should be understood that the invention can be practiced in different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided to make the disclosure thorough and complete and to fully convey the scope of the invention to those skilled in the art.
[0022] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms, unless the context clearly indicates otherwise. The terms “comprising” and / or “including,” when used in this specification, identify the presence of said features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.
[0023] To fully understand the present invention, a detailed structure will be presented in the following description in order to illustrate the technical solution proposed by the present invention; optional embodiments of the present invention are described in detail below, however, in addition to these detailed descriptions, the present invention may have other embodiments.
[0024] like Figure 1 As shown, in one embodiment, a method for testing the performance of a high-voltage circuit breaker with interference removal is provided. This method includes steps S101 to S106, which are detailed below: S101. When the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, trigger the high-voltage circuit breaker operating mechanism to perform a tripping operation and obtain the first electromagnetic wave signal. By triggering the operating mechanism to open and acquiring the first electromagnetic wave signal when the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, this invention can extract the interference characteristics of the operating mechanism as a reference signal under the condition of no interference from the arc-extinguishing chamber radiation signal, thus providing a reliable comparison basis for accurate identification and elimination of interference from the same source during subsequent energized testing.
[0025] Preferably, before conducting on-site testing, this application establishes an operating mechanism simulation test platform in a laboratory environment to obtain prior knowledge of the interference. (Reference) Figure 2 The diagram shown illustrates the platform, which includes: Control switch module: It consists of opto-isolating switch, switching power supply, isolating switch signal control device and host computer (running LabVIEW control program), and is used to precisely control the timing of the actions of each measured component.
[0026] Signal measurement module: includes a radiated electromagnetic wave sensor with an operating frequency band of 0.5-2GHz, a UHF conditioner (for filtering, amplification and detection), a high-voltage probe and an oscilloscope, used for acquiring and processing electromagnetic wave signals.
[0027] The module under test includes typical electromagnetic components of the high-voltage circuit breaker operating mechanism, such as relays, opening and closing coils, and auxiliary switches. Each component is connected to a DC 220V circuit through a protective resistor to simulate field operating conditions.
[0028] Furthermore, by controlling the conduction of the opto-isolating switch, the relay, the opening and closing coils, and the auxiliary switch are triggered independently. Using a radiated electromagnetic wave sensor and a UHF conditioner, the radio frequency signals and detection signals generated when each component operates are collected at a specific distance.
[0029] In some embodiments, the operating signal of relay JZY1-22 is measured as two pulses with an amplitude of about 100mV, and the detector signal shows a cluster of signals with an amplitude of about 400mV at 0ms; while the signal of the opening and closing coil CT19-VS1 presents an irregular radio frequency signal lasting about 10ms and occurring about 14 times.
[0030] Preferably, before acquiring the first electromagnetic wave signal, the method further includes: Using a simulation test platform, electromagnetic wave signals generated by relays, opening and closing coils and auxiliary switches in the operating mechanism of high-voltage circuit breakers during actual operation are collected. The signal amplitude, duration, occurrence time and energy attenuation law of each electromagnetic component are extracted, and an electromagnetic wave feature library of the operating mechanism indexed by electromagnetic component type is established. Based on the electromagnetic wave characteristic library of the operating mechanism, the known operating sequence of each electromagnetic component is determined.
[0031] In some embodiments, before acquiring the first electromagnetic wave signal, the method further includes: The electromagnetic wave signals, duration, and occurrence time of each electromagnetic component generated by the high-voltage circuit breaker operating mechanism during actual operation are collected. The electromagnetic components in the high-voltage circuit breaker operating mechanism include relays, opening and closing coils, and auxiliary switches. The known operating sequence of each electromagnetic element is determined by the electromagnetic wave signal of each electromagnetic element.
[0032] By pre-collecting the electromagnetic wave signals, durations, and occurrence times generated by various electromagnetic components such as relays, opening and closing coils, and auxiliary switches in the operating mechanism of a high-voltage circuit breaker during actual operation, and determining the known action sequence of each electromagnetic component accordingly, this invention can establish a priori knowledge base of interference characteristics for different electromagnetic components. This provides a basis for accurately locating the theoretical interference time window generated by each component during subsequent live-line testing, significantly improving the pertinence and accuracy of interference signal identification in the operating mechanism, and avoiding misjudgments or omissions caused by confusion of interference characteristics of different components.
[0033] S102. When the high-voltage circuit breaker under test is energized and performs a breaking operation, a second electromagnetic wave signal is acquired. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. By acquiring a second electromagnetic wave signal when the high-voltage circuit breaker under test is energized and performs an interruption operation, and this signal simultaneously contains the arc-extinguishing chamber radiation signal and the operating mechanism interference signal that is of the same origin as the first electromagnetic wave signal, the present invention can completely acquire the mixed signal under real operating conditions. By utilizing the characteristic that the interference component in the second electromagnetic wave signal is of the same origin as the first electromagnetic wave signal, the present invention provides a data foundation for subsequent accurate separation of interference and effective signal through time domain, frequency domain, and time sequence comparison, thereby solving the problem of distortion in arc-extinguishing chamber radiation signal extraction caused by the inability to distinguish interference of the same origin in the prior art.
[0034] In some embodiments, the first electromagnetic wave signal and the second electromagnetic wave signal are acquired by a radiated electromagnetic wave sensor, the operating frequency band of which is 0.5 GHz to 2 GHz.
[0035] Preferably, at the installation site of the high-voltage circuit breaker under test, with its high-voltage main circuit not powered, its operating mechanism is triggered to perform a tripping operation. During this process, no current is interrupted in the arc-extinguishing chamber, so no effective radiated signal is generated. The electromagnetic wave signal generated during this process is synchronously collected by a radiated electromagnetic wave sensor. This signal only contains interference components generated when the various electromagnetic components within the operating mechanism, such as relays, opening and closing coils, and auxiliary switches, are activated. Therefore, this is recorded as the first electromagnetic wave signal, serving as the reference interference signal for subsequent comparative analysis.
[0036] like Figure 3 (a) and Figure 4 As shown in (a), the no-load tripping signals, i.e. the first electromagnetic wave signals, were collected from the 126kV and 35kV circuit breakers, respectively. It can be seen that obvious interference pulses appear at specific times (such as -32ms and 18ms), which are typical manifestations of interference in the operating mechanism.
[0037] After the high-voltage circuit breaker returns to normal energized operation, it is triggered again to perform a normal breaking operation when needed. During this energized breaking process, electromagnetic wave signals are synchronously collected by the same radiated electromagnetic wave sensor. The second electromagnetic wave signal collected at this time is a mixture of the effective electromagnetic radiation signal generated by the arc interruption in the arc-extinguishing chamber and the interference signal generated by the renewed action of the operating mechanism. Since the operating mechanism is triggered in both S102 and S103, the interference signal it generates is from the same source as the first electromagnetic wave signal.
[0038] like Figure 3 (b) and Figure 4 As shown in (b), the corresponding live trip signals, i.e., the second electromagnetic wave signals, were collected from the 126kV and 35kV circuit breakers, respectively. It can be seen that the signal contains both interference pulses similar to the no-load signal and radiation signals generated by the arc-extinguishing chamber.
[0039] S103. Preset multiple time intervals, calculate the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal in each time interval, and determine the interference interval when the correlation coefficient exceeds the first preset threshold. By presetting multiple time intervals and calculating the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal in each interval, and then determining the intervals where the correlation coefficient exceeds a first preset threshold as interference intervals, this invention can quantitatively identify time segments in the second electromagnetic wave signal that are highly similar to the reference interference signal in the time domain. This allows for precise location of the occurrence time of the interference signal of the operating mechanism, avoiding blind processing of the entire signal, significantly improving the efficiency and accuracy of interference identification, and providing a reliable time positioning basis for subsequent targeted removal of interference components.
[0040] S104. Perform Fourier transform on the second electromagnetic wave signal and the first electromagnetic wave signal respectively, compare the distribution characteristics of their energy in each frequency component, and take the frequency band with the similarity of distribution characteristics exceeding the second preset value as the interference frequency band. By performing Fourier transforms on the second and first electromagnetic wave signals respectively and comparing the energy distribution characteristics of the two signals at each frequency component, frequency bands with similarity exceeding a second preset value are identified as interference frequency bands. This invention can quantitatively identify frequency components in the second electromagnetic wave signal that are highly consistent with the energy distribution of the reference interference signal in the frequency domain. This effectively overcomes the limitation that time domain analysis cannot distinguish signals with overlapping frequency bands, and achieves accurate positioning of the frequency characteristics of interference signals of the operating mechanism. This provides a reliable frequency basis for subsequent targeted removal of interference components in the frequency domain.
[0041] S105. Obtain the timing sequence of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test, and determine the theoretical interference time. By acquiring the operating sequence of various electromagnetic components such as relays, opening and closing coils, and auxiliary switches within the operating mechanism of the high-voltage circuit breaker under test and determining the theoretical interference time accordingly, this invention can pre-lock the expected window of interference that may be generated by each electromagnetic component in the time dimension. This narrows the interference search range from the entire time domain to a limited theoretical time interval, avoiding the waste of computational resources and the risk of misjudgment caused by blind searching. It improves the pertinence and efficiency of interference identification and provides precise time constraints for subsequent comprehensive judgment by combining time-domain related intervals and frequency-domain similar frequency bands.
[0042] S106. The interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time are determined as the operating mechanism interference signal, and they are removed from the second electromagnetic wave signal to obtain the arc extinguishing chamber electromagnetic radiation signal. This invention employs a redundant confirmation mechanism that combines time domain, frequency domain, and time sequence three-dimensional joint judgment. This effectively avoids misjudgment or omission caused by accidental factors in single-dimensional judgment. It ensures that only interference components truly originating from the operating mechanism are accurately identified and eliminated. This significantly improves the effectiveness of signal extraction while preserving the integrity of the arc-extinguishing chamber radiation signal to the maximum extent, laying a reliable data foundation for the accurate evaluation of the circuit breaker's breaking performance.
[0043] In some embodiments, the electromagnetic radiation signal of the arc-extinguishing chamber is removed from the second electromagnetic wave signal to obtain the electromagnetic radiation signal of the arc-extinguishing chamber, specifically including: The second electromagnetic wave signal is subjected to discrete wavelet transform to obtain transform data at each scale, including wavelet coefficients. Based on the interference range, interference frequency band, and theoretical interference time, determine the wavelet coefficients corresponding to the interference signal of the operating mechanism; Thresholding is performed on the wavelet coefficients corresponding to the interference signals of the operating mechanism; Discrete wavelet inverse transform is performed on the thresholded transform data at each scale to obtain the electromagnetic radiation signal of the arc-extinguishing chamber.
[0044] The second electromagnetic wave signal is decomposed into transform data (including wavelet coefficients) at various scales using discrete wavelet transform. The multi-scale characteristics of wavelet transform are used to separate components with different frequencies and time-domain features in the signal. By combining multi-dimensional information such as interference interval, interference frequency band, and theoretical interference time, the wavelet coefficients corresponding to the interference signal of the operating mechanism are accurately located, ensuring that the interference components are accurately identified. Thresholding is performed on the wavelet coefficients in this part. By suppressing the energy or features of the wavelet coefficients corresponding to the interference, the interference signal is accurately weakened. Finally, discrete wavelet inverse transform is performed on the thresholded transform data at each scale to restore the processed transform data to the time-domain signal. This removes the interference from the operating mechanism from the mixed second electromagnetic wave signal and extracts the electromagnetic radiation signal of the arc-extinguishing chamber, providing a high-quality data foundation for the reliable evaluation of the breaking performance of the high-voltage circuit breaker.
[0045] In some embodiments, thresholding processing is performed on the wavelet coefficients corresponding to the interference signal of the operating mechanism, specifically including: If the absolute value of a wavelet coefficient is greater than or equal to the scale correlation threshold, then the wavelet coefficient is retained. If the absolute value of a wavelet coefficient is less than the scale correlation threshold, then the wavelet coefficient is set to zero. The formula for calculating the scale-related threshold is: λi=σi
[0046] In the formula, i is the scale number, ni is the length of the wavelet coefficient at the i-th scale, σi is the noise standard deviation estimate of the wavelet coefficient at the i-th scale, and λi is the threshold of the wavelet coefficient at the i-th scale.
[0047] In some embodiments, the noise standard deviation estimate σi of the wavelet coefficients at the i-th scale is determined according to the following formula:
[0048] In the formula, i is the scale index, k is the position index of the wavelet coefficient at the i-th scale, and MAD(·) represents the median of the set of absolute values of all wavelet coefficients. Let be the wavelet coefficient at the k-th position on the i-th scale, and let q be 0.6745. Let be the length of the wavelet coefficients at the i-th scale.
[0049] By employing scale-adaptive wavelet coefficient thresholding, wavelet coefficients with absolute values greater than or equal to the scale-related threshold are retained, while those less than the threshold are set to zero. This achieves hierarchical and differentiated processing of wavelet coefficients, avoiding the problem of excessive suppression of low-frequency effective signals or residual high-frequency interference caused by uniform processing across all scales with fixed thresholds. Thus, while effectively filtering out interference signals and white noise from the operating mechanism, the original characteristics and energy integrity of the electromagnetic radiation signal from the arc-extinguishing chamber are preserved to the greatest extent, significantly improving denoising accuracy and signal fidelity.
[0050] like Figure 3 and Figure 4 As shown in the comparison, the above method can successfully extract the signal from the energized tripping signal (…). Figure 3 Identify and remove signals that are related to the no-load tripping signal from b, 4b) Figure 3 Interference pulses with consistent position and characteristics in (a, 4a) (e.g., -32ms and 18ms pulses from the 126kV circuit breaker, and -20ms, 18ms, and 23ms pulses from the 35kV circuit breaker) are used to extract effective signal pulses generated solely by the arc-extinguishing chamber (e.g., ... Figure 3 The 5ms and 25ms pulses in b Figure 4 (14-16ms pulse in b).
[0051] S107. Evaluate the breaking performance of high-voltage circuit breakers based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0052] In some embodiments, the breaking performance of a high-voltage circuit breaker is evaluated based on the electromagnetic radiation signal from the arc-extinguishing chamber, specifically including: Acquire the reference characteristic data of the high-voltage circuit breaker. The reference characteristic data of the high-voltage circuit breaker is the characteristic range of the electromagnetic radiation signal of the arc-extinguishing chamber of a high-voltage circuit breaker with known qualified breaking performance when performing a breaking operation. The amplitude, number of pulses, energy, spectral characteristics, and occurrence time of the electromagnetic radiation signal extracted from the arc-extinguishing chamber of the high-voltage circuit breaker under test are analyzed to obtain the characteristic data of the circuit breaker under test. The feature data to be tested is compared with the benchmark feature data; When the test feature data is within the feature range of the reference feature data, the breaking performance of the high voltage circuit breaker under test is determined to be normal. When the characteristic data to be tested is not within the characteristic range of the reference characteristic data, the breaking performance of the high-voltage circuit breaker under test is determined to be abnormal.
[0053] By extracting the electromagnetic radiation signal from the arc-extinguishing chamber after interference removal processing and analyzing at least one of its amplitude, pulse count, energy, spectral characteristics, and occurrence time as the target feature data, and then comparing it with the reference feature range of a known qualified high-voltage circuit breaker, the breaking performance is determined to be normal or abnormal based on whether the target feature data falls within the reference range. This invention achieves objective performance evaluation based on the electromagnetic radiation signal from the arc-extinguishing chamber, avoiding the problem of misjudgment caused by feature distortion due to interference signal aliasing in traditional methods. This significantly improves the accuracy and reliability of circuit breaker breaking performance detection and provides a scientific decision-making basis for power equipment condition assessment.
[0054] Specifically, if the characteristic value of the signal under test is within the reference characteristic range, the breaking performance of the current high-voltage circuit breaker is determined to be normal. If the characteristic value of the signal under test, such as excessively low amplitude, abnormal energy, or a significant deviation from the theoretical arcing time, exceeds the reference characteristic range, the breaking performance is determined to be abnormal, and there may be defects such as arc-extinguishing chamber wear or insufficient SF6 gas pressure.
[0055] This application also proposes a high-voltage circuit breaker performance testing system for interference removal, the system including: a signal acquisition unit, a time domain comparison unit, a frequency domain comparison unit, a timing location unit, an interference removal unit, and a performance evaluation unit; The signal acquisition unit is used to trigger the high-voltage circuit breaker operating mechanism to perform a tripping operation when the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, and to acquire a first electromagnetic wave signal; when the high-voltage circuit breaker under test is energized and performs a tripping operation, it acquires a second electromagnetic wave signal. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. The time-domain comparison unit is used to preset multiple time intervals, calculate the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal in each time interval, and determine the interference interval when the correlation coefficient exceeds the first preset threshold. The frequency domain comparison unit is used to perform Fourier transforms on the second electromagnetic wave signal and the first electromagnetic wave signal respectively, compare the energy distribution characteristics of the two at each frequency, and select the signal with the highest similarity in distribution characteristics. The preset frequency band is used as the interference frequency band; The timing positioning unit is used to acquire the action timing of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test and determine the theoretical interference time. The interference elimination unit is used to identify the interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time as operating mechanism interference signals, and to eliminate them from the second electromagnetic wave signal to obtain the arc extinguishing chamber electromagnetic radiation signal. The performance evaluation unit is used to evaluate the breaking performance of high-voltage circuit breakers based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0056] This application also proposes a readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the following steps: When the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, the high-voltage circuit breaker operating mechanism is triggered to perform a tripping operation to obtain the first electromagnetic wave signal. When the high-voltage circuit breaker under test is energized and performs a breaking operation, a second electromagnetic wave signal is acquired. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. Multiple time intervals are preset, and the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal is calculated in each time interval to determine the interference interval when the correlation coefficient exceeds the first preset threshold. Fourier transforms are performed on the second electromagnetic wave signal and the first electromagnetic wave signal respectively. The distribution characteristics of their energy in each frequency component are compared. The frequency bands whose similarity in distribution characteristics exceeds a second preset value are taken as interference frequency bands. Obtain the timing sequence of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test, and determine the theoretical interference time. The interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time are identified as the operating mechanism interference signal, and are removed from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The breaking performance of high-voltage circuit breakers is evaluated based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0057] This application also proposes a computer device, including a memory and a processor, wherein the memory stores a computer program, and the computer program is executed by the processor in the following steps: When the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, the high-voltage circuit breaker operating mechanism is triggered to perform a tripping operation to obtain the first electromagnetic wave signal. When the high-voltage circuit breaker under test is energized and performs a breaking operation, a second electromagnetic wave signal is acquired. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. Multiple time intervals are preset, and the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal is calculated in each time interval to determine the interference interval when the correlation coefficient exceeds the first preset threshold. Fourier transforms are performed on the second electromagnetic wave signal and the first electromagnetic wave signal respectively. The distribution characteristics of their energy in each frequency component are compared. The frequency bands whose similarity in distribution characteristics exceeds a second preset value are taken as interference frequency bands. Obtain the timing sequence of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test, and determine the theoretical interference time. The interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time are identified as the operating mechanism interference signal, and are removed from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The breaking performance of high-voltage circuit breakers is evaluated based on the electromagnetic radiation signal from the arc-extinguishing chamber.
[0058] Those skilled in the art will understand that implementing all or part of the processes in the above embodiments can be accomplished by instructing related hardware through a computer program. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.
[0059] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0060] The embodiments described above are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application's patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. The embodiments disclosed above are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made according to the claims of this invention are still within the scope of this invention.
Claims
1. A method for testing the performance of a high-voltage circuit breaker with interference removal, characterized in that, The method includes: When the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, the high-voltage circuit breaker operating mechanism is triggered to perform a tripping operation to obtain the first electromagnetic wave signal. When the high-voltage circuit breaker under test is energized and performs a breaking operation, a second electromagnetic wave signal is acquired. The second electromagnetic wave signal includes the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal. Multiple time intervals are preset, and the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal is calculated in each time interval to determine the interference interval when the correlation coefficient exceeds a first preset threshold. Fourier transforms are performed on the second electromagnetic wave signal and the first electromagnetic wave signal respectively. The distribution characteristics of their energy in each frequency component are compared, and the frequency bands whose similarity in distribution characteristics exceeds a second preset value are taken as interference frequency bands. The timing sequence of the operation of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test is obtained to determine the theoretical interference time. The interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time are identified as operating mechanism interference signals, and are removed from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The breaking performance of the high-voltage circuit breaker is evaluated based on the electromagnetic radiation signal from the arc-extinguishing chamber.
2. The high-voltage circuit breaker performance testing method for interference removal according to claim 1, characterized in that, Before acquiring the first electromagnetic wave signal, the method further includes: The electromagnetic wave signals, duration, and occurrence time of each electromagnetic element generated by the high-voltage circuit breaker operating mechanism during actual operation are collected. The electromagnetic elements in the high-voltage circuit breaker operating mechanism include relays, opening and closing coils, and auxiliary switches. The known operating sequence of each electromagnetic element is determined by the electromagnetic wave signal of each electromagnetic element.
3. The high-voltage circuit breaker performance testing method for interference removal according to claim 1, characterized in that, The process of removing it from the second electromagnetic wave signal to obtain the electromagnetic radiation signal of the arc-extinguishing chamber specifically includes: The second electromagnetic wave signal is subjected to discrete wavelet transform to obtain transform data at each scale, and the transform data includes wavelet coefficients. Based on the interference range, interference frequency band, and theoretical interference time, determine the wavelet coefficients corresponding to the interference signal of the operating mechanism; The wavelet coefficients corresponding to the interference signal of the operating mechanism are thresholded. Discrete wavelet inverse transform is performed on the thresholded transform data at each scale to obtain the electromagnetic radiation signal of the arc-extinguishing chamber.
4. The high-voltage circuit breaker performance testing method for interference removal according to claim 3, characterized in that, The thresholding process for the wavelet coefficients corresponding to the interference signal of the operating mechanism specifically includes: If the absolute value of the wavelet coefficient is greater than or equal to the scale correlation threshold, then the wavelet coefficient is retained. If the absolute value of the wavelet coefficient is less than the scale correlation threshold, then the wavelet coefficient is set to zero; The formula for calculating the scale-related threshold is: λi=σi In the formula, i is the scale number, ni is the length of the wavelet coefficient at the i-th scale, σi is the noise standard deviation estimate of the wavelet coefficient at the i-th scale, and λi is the threshold of the wavelet coefficient at the i-th scale.
5. The high-voltage circuit breaker performance testing method for interference removal according to claim 4, characterized in that, The noise standard deviation estimate σi of the wavelet coefficients at the i-th scale is determined using the following formula: In the formula, i is the scale index, k is the position index of the wavelet coefficient at the i-th scale, and MAD(·) represents the median of the set of absolute values of all wavelet coefficients. Let be the wavelet coefficient at the k-th position on the i-th scale, and let q be 0.6745. Let be the length of the wavelet coefficients at the i-th scale.
6. The method for testing the performance of a high-voltage circuit breaker with interference removal according to claim 1, 2, or 3, characterized in that, The first electromagnetic wave signal and the second electromagnetic wave signal are acquired by a radiated electromagnetic wave sensor, the operating frequency band of which is 0.5 GHz to 2 GHz.
7. The interference-removal high-voltage circuit breaker performance testing method according to claim 6, characterized in that, The evaluation of the breaking performance of the high-voltage circuit breaker based on the electromagnetic radiation signal from the arc-extinguishing chamber specifically includes: Acquire reference characteristic data of high-voltage circuit breakers, wherein the reference characteristic data of high-voltage circuit breakers is the characteristic range of electromagnetic radiation signal of the arc-extinguishing chamber of a high-voltage circuit breaker with known qualified breaking performance when performing a breaking operation. The amplitude, number of pulses, energy, spectral characteristics, and occurrence time of the electromagnetic radiation signal from the arc-extinguishing chamber extracted from the high-voltage circuit breaker under test are analyzed to obtain the characteristic data to be tested. The test feature data is compared with the reference feature data; When the test feature data is within the feature range of the reference feature data, the breaking performance of the high-voltage circuit breaker under test is determined to be normal. When the test feature data is not within the feature range of the reference feature data, the breaking performance of the high-voltage circuit breaker under test is determined to be abnormal.
8. A high-voltage circuit breaker performance testing system for interference removal, characterized in that, The system includes: a signal acquisition unit, a time-domain comparison unit, a frequency-domain comparison unit, a timing positioning unit, an interference removal unit, and a performance evaluation unit; The signal acquisition unit is used to trigger the high-voltage circuit breaker operating mechanism to perform a tripping operation when the high-voltage main circuit of the high-voltage circuit breaker under test is not energized, and to acquire a first electromagnetic wave signal; when the high-voltage circuit breaker under test is energized and performs a tripping operation, it acquires a second electromagnetic wave signal, the second electromagnetic wave signal including the radiation signal generated by the arc-extinguishing chamber inside the high-voltage circuit breaker and the interference signal of the operating mechanism that is from the same source as the first electromagnetic wave signal; The time-domain comparison unit is used to preset multiple time intervals, calculate the correlation coefficient between the second electromagnetic wave signal and the first electromagnetic wave signal in each time interval, and determine the interference interval when the correlation coefficient exceeds a first preset threshold. The frequency domain comparison unit is used to perform Fourier transforms on the second electromagnetic wave signal and the first electromagnetic wave signal respectively, compare the energy distribution characteristics of the two at each frequency, and select the signal with the highest similarity in distribution characteristics. The preset frequency band is used as the interference frequency band; The timing positioning unit is used to acquire the action timing of each electromagnetic component in the operating mechanism of the high-voltage circuit breaker under test, and to determine the theoretical interference time. The interference elimination unit is used to identify the interference range related to the first electromagnetic wave signal, the interference frequency band similar to the first electromagnetic wave signal and the signal components whose time falls within the theoretical interference time as operating mechanism interference signals, and to eliminate them from the second electromagnetic wave signal to obtain the arc-extinguishing chamber electromagnetic radiation signal. The performance evaluation unit is used to evaluate the breaking performance of the high-voltage circuit breaker based on the electromagnetic radiation signal from the arc-extinguishing chamber.
9. A readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, the processor performs the steps of the method as described in any one of claims 1 to 7.
10. A computer device, comprising a memory and a processor, characterized in that, The memory stores a computer program that, when executed by the processor, causes the processor to perform the steps of the method as described in any one of claims 1 to 7.