A circuit breaker vacuum degree detection method based on electron collision radiation inversion

Abstract

This invention discloses a method for detecting the vacuum degree of a circuit breaker based on electron collision radiation inversion, belonging to the field of power equipment testing. The method includes the following steps: Step S1, synchronously acquiring X-ray pulse signals from multiple measuring points outside the arc-extinguishing chamber of the vacuum circuit breaker, extracting and parameterizing the pulse events to obtain the temporal distribution characteristics reflecting electron collision behavior; Step S2, establishing a feature enhancement model based on electron collision probability; Step S3, establishing a mapping model between the X-ray generation mechanism and the electron collision process, and then inverting the vacuum degree. This invention provides a method for detecting the vacuum degree of a circuit breaker based on electron collision radiation inversion. By establishing a physical mapping relationship between the statistical characteristics of X-ray pulse events and the electron mean free path and collision probability, it achieves quantitative inversion of the vacuum degree, thereby improving detection accuracy and physical interpretability.

Description

Technical Field

[0001] This invention relates to a method for detecting the vacuum level of circuit breakers based on electron collision radiation inversion, belonging to the field of power equipment testing. Background Technology

[0002] The arc-extinguishing chamber of a vacuum circuit breaker relies on a high vacuum environment to achieve excellent insulation and arc-extinguishing performance. When the vacuum level decreases, the density of residual gas molecules in the gap increases, and the movement of electrons under the action of the electric field gradually transitions from a collision-free state to a collision-dominated process, thereby causing ionization, excitation and energy loss, accompanied by enhanced X-ray radiation.

[0003] Currently, existing vacuum level assessment methods primarily employ X-ray detection, indirectly evaluating the vacuum state by measuring radiation intensity or pulse count rate. However, these methods generally suffer from the following shortcomings: 1. Treating X-ray signals as general signal processing objects lacks a quantitative correlation with electron motion and collision mechanisms.

[0004] 2. It relies on statistical characteristics or empirical models for state determination, lacking a clear physical explanation.

[0005] 3. It cannot achieve quantitative inversion of vacuum degree parameters; it can only perform qualitative or graded judgments.

[0006] Therefore, there is an urgent need for an X-ray signal analysis method based on electron collision and radiation mechanisms to realize the inversion calculation of radiation signals into vacuum parameters. Summary of the Invention

[0007] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a circuit breaker vacuum degree detection method based on electron collision radiation inversion. By establishing a physical mapping relationship between the statistical characteristics of X-ray pulse events and the mean free path and collision probability of electrons, the vacuum degree can be quantitatively inverted, thereby improving the detection accuracy and physical interpretability.

[0008] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A method for detecting the vacuum degree of a circuit breaker based on electron collision radiation inversion includes the following steps: Step S1: Simultaneously collect X-ray pulse signals from multiple measuring points outside the vacuum circuit breaker arc extinguishing room, extract and parameterize the pulse events to obtain the time distribution characteristics reflecting electron collision behavior; Step S2: Establish a feature enhancement model based on electron collision probability; Step S3: Establish a mapping model between the X-ray generation mechanism and the electron collision process, and then invert the vacuum degree. Step S4: Perform a joint correction on the vacuum degree result obtained by inversion based on statistical stability and spatial response characteristics to obtain the corrected vacuum degree result.

[0009] Furthermore, in step S1, X-ray pulse signals are simultaneously acquired at multiple measuring points outside the vacuum circuit breaker arc extinguishing chamber, specifically including the following steps: Multiple X-ray detectors are arranged axially or radially outside the arc-extinguishing chamber of the vacuum circuit breaker. A voltage is applied across the moving and stationary contacts of the vacuum circuit breaker arc-extinguishing chamber at a given opening distance d. U Then, X-ray pulse signals were acquired to obtain multi-channel time series. X ( t The multi-channel time series X ( t The expression for ) is as follows:

[0010] in, These are electrical pulses triggered by X-ray photons.

[0011] Furthermore, in step S1, the pulse events are extracted and parameterized to obtain the temporal distribution characteristics reflecting the electron collision behavior, specifically including the following steps: Threshold discrimination and pulse detection were performed on the acquired X-ray pulse signals to extract pulse event sequences. E The pulse event sequence E The expression is as follows:

[0012] in, t i For the first i The time of occurrence of each X-ray pulse A i This represents the amplitude corresponding to the X-ray pulse. pass t i Obtain the X-ray pulse event rate per unit time R x ( t The X-ray pulse event rate per unit time R x ( t The expression for ) is as follows:

[0013] in, For statistical time windows, t i For the first i The time of occurrence of each X-ray pulset i+1 For the first i +1 X-ray pulse occurrence time, N x for Δt The number of X-ray pulses that occur within a given time period.

[0014] Furthermore, in step S2, establishing a feature enhancement model based on electron collision probability specifically includes the following steps: First, calculate the mean free path of the electron in statistical probability derived from multi-point X-rays. l e The calculation formula is as follows:

[0015] in, This represents the average time interval between adjacent X-ray pulse events; Statistical time window for each unit; This refers to the electron drift velocity; m e Electron mobility; d The distance between the moving and stationary contacts in the arc-extinguishing chamber of a vacuum circuit breaker; U The voltage applied across the moving and stationary contacts of the vacuum circuit breaker arc-extinguishing chamber under the opening distance d condition; Then, a weighting function related to electron collisions is constructed. The weighting function related to electron collisions The expression is as follows:

[0016] in, Let be the electron collision radiation efficiency coefficient; d The distance between the moving and stationary contacts in the arc-extinguishing chamber of a vacuum circuit breaker; Finally, the enhanced expression of unit impulse event rate was obtained. The enhanced expression of the unit impulse event rate The expression is as follows:

[0017] in, R x ( t () represents the X-ray pulse event rate per unit time. This is a weighting function related to electron collisions.

[0018] Furthermore, the expression for the mapping model between the X-ray generation mechanism and the electron collision process in step S3 is as follows:

[0019] in, R x ( t () represents the X-ray pulse event rate per unit time. K These are the system parameters obtained through calibration experiments. d The distance between the moving and stationary contacts in the arc-extinguishing chamber of a vacuum circuit breaker. l e It is the mean free path of the electron.

[0020] Furthermore, in step S3, the vacuum degree is obtained by inversion, which specifically includes the following steps: Vacuum degree is obtained by inversion using gas dynamics relationships p ( t The vacuum degree obtained by inversion p ( t The calculation formula for ) is as follows:

[0021] in, k Boltzmann's constant; T The thermodynamic temperature of the gas inside the arc-extinguishing chamber of a vacuum circuit breaker; d The opening distance between the moving and stationary contacts of the arc-extinguishing chamber of a vacuum circuit breaker; d m The equivalent diameter of a gas molecule; is an enhanced expression for the unit impulse event rate; K is a system parameter obtained through calibration experiments.

[0022] Furthermore, in step S4, the vacuum degree result obtained by inversion is jointly corrected based on statistical stability and spatial response characteristics to obtain the corrected vacuum degree result, specifically including the following steps: Step S41: Calculate the average vacuum degree ; Step S42: Calculate the vacuum degree obtained from the inversion. p ( t variance of ) oh i By combining the response of the X-ray detector to the space radiation source, the spatial response coefficient was calculated. ; Step S43: Calculate the corrected vacuum degree. p s ( t ).

[0023] Furthermore, the average vacuum degree The calculation formula is as follows:

[0024] in, p( t ) represents the vacuum degree obtained through inversion.

[0025] Furthermore, the spatial response coefficient The calculation formula is as follows:

[0026] in, Indicates spatial location r The contribution weight of the radiation source to the i-th X-ray detector. oh i The vacuum degree obtained by inversion p ( t The variance of ).

[0027] Furthermore, the corrected vacuum degree p s ( t The calculation formula for ) is as follows:

[0028] in, For spatial response coefficients, p ( t ) represents the vacuum degree obtained through inversion.

[0029] By employing the above technical solution, this invention transforms X-ray pulse signals from traditional statistical representations into physical representations of electron collision processes. By introducing the electron mean free path and collision probability, a direct correlation between the radiation signal and gas state parameters is achieved, transforming vacuum degree from empirical judgment to a calculable physical inversion result. Through constraint correction combining temporal statistical stability and spatial response functions, errors caused by random pulse fluctuations and spatial non-uniformity are significantly reduced, thereby improving the stability of vacuum degree measurement results. Attached Figure Description

[0030] Figure 1 This is a flowchart of a circuit breaker vacuum degree detection method based on electron collision radiation inversion according to the present invention; Figure 2 This is a schematic diagram showing the X-ray detector of the present invention arranged along the axial direction of the arc-extinguishing chamber of the vacuum circuit breaker; Figure 3 This is a schematic diagram showing the X-ray detector of the present invention arranged radially along the arc-extinguishing chamber of the vacuum circuit breaker. Detailed Implementation

[0031] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0032] like Figure 1As shown, this embodiment provides a method for detecting the vacuum degree of a circuit breaker based on electron collision radiation inversion, including the following steps: Step S1: Simultaneously acquire X-ray pulse signals from multiple measuring points outside the vacuum circuit breaker arc extinguishing chamber, extract and parameterize the pulse events to obtain the temporal distribution characteristics reflecting electron collision behavior. Specifically: First, such as Figure 2 , 3 As shown, multiple X-ray detectors 2 are arranged axially or radially outside the vacuum circuit breaker arc-extinguishing chamber 1. A voltage is applied across the moving and stationary contacts of the vacuum circuit breaker arc-extinguishing chamber under the opening distance d. U Then, X-ray pulse signals were acquired to obtain multi-channel time series. X ( t ):

[0033] The multi-channel time series in this embodiment X ( t ( ) refers to the sequence of electrical pulses triggered by X-ray photons. Before processing, the acquired X-ray pulse signals appear as electrical pulse sequences; these electrical pulse sequences are... .

[0034] Then, threshold discrimination and pulse detection are performed on the acquired X-ray pulse signals. The specific methods are as follows: Multi-channel time series signals X ( t In ), when the signal amplitude is at a certain moment t i An X-ray pulse event is considered valid if the following conditions are met: 1. At any time t i Location, signal X ( t Local maxima appear; 2. The amplitude corresponding to this maximum value is denoted as And satisfy:

[0035] in, A th The preset amplitude discrimination threshold is used; 3. The time interval between two adjacent pulse events satisfies:

[0036] in, This is the minimum pulse resolution time.

[0037] Based on the above criteria, fromX ( t Extracting pulse event sequences E Pulse event sequence E The expression is as follows:

[0038] in, t i It is the first i The time of occurrence of each X-ray pulse A i It is the amplitude (characterizing radiation intensity) corresponding to the X-ray pulse. pass t i Obtain the X-ray pulse event rate per unit time R x ( t X-ray pulse event rate per unit time R x ( t The expression for ) is as follows:

[0039] in, The unit is the statistical time window, that is, the number of X-ray pulses is counted within this time window; t i For the first i The time of occurrence of each X-ray pulse t i+1 For the first i +1 X-ray pulse occurrence time, N x yes Δt The number of X-ray pulses that occur within a given time period.

[0040] Step S2: Establish a feature enhancement model based on electron collision probability. Specifically: This embodiment utilizes the inherent correlation between the pulse event rate and the electron transport process, introduces the electron mobility to construct an equivalent mean free path, and further establishes a feature enhancement model based on the electron collision probability, so that the original pulse statistics are transformed into physical quantities directly related to the electron collision intensity.

[0041] First, calculate the mean free path of the electron in statistical probability derived from multi-point X-rays. l e The calculation formula is as follows:

[0042] in, This represents the average time interval between adjacent X-ray pulse events; This refers to the electron drift velocity; m e Electron mobility is related to the type of gas and pressure. d The distance between the moving and stationary contacts in the arc-extinguishing chamber of a vacuum circuit breaker; U To be at the opening distance d The voltage applied across the moving and stationary contacts of the arc-extinguishing chamber of a vacuum circuit breaker under certain conditions; Then, a weighting function related to electron collisions is constructed. Weighting function related to electron collisions The expression is as follows:

[0043] in, The electron collision radiation efficiency coefficient represents the proportion of kinetic energy of an electron converted into X-ray radiation energy during a collision with the electrode material. Finally, the enhanced expression of unit impulse event rate was obtained. Enhanced expression of unit impulse event rate The expression is as follows:

[0044] in, R x ( t () represents the X-ray pulse event rate per unit time.

[0045] Step S3: Since X-ray generation is directly related to electron collisions with the metal surface, a mapping model between the X-ray generation mechanism and the electron collision process is established. Then, the vacuum degree is obtained by inverting the gas dynamics relationship, realizing the quantitative inversion from the enhanced event rate to the vacuum degree parameter. Compared with traditional empirical evaluation methods based on X-ray intensity or count rate, this step has the following significant advantages: 1. Establish a direct link between X-ray signals and electron mean free path and collision probability, realizing the transformation from "signal statistics" to "physical mechanism".

[0046] 2. By constructing an inversion formula through a gas dynamics model, the vacuum degree value can be directly calculated, rather than just judging the level, thus realizing a quantitative inversion of the vacuum degree.

[0047] 3. By enhancing the collision probability weight, the influence of random pulse fluctuations is effectively suppressed, resulting in strong anti-interference ability.

[0048] 4. All parameters can be obtained through experimental calibration or by looking up tables, providing a basis for practical application.

[0049] In this embodiment, the mapping model is constructed as follows: a voltage is applied between the moving and stationary contacts of the vacuum circuit breaker arc-extinguishing chamber. Subsequently, electrons in the gap move under the influence of the electric field; when electrons collide with residual gas molecules or the electrode surface, excitation, ionization, and bremsstrahlung processes occur, thus forming a pulse signal that can be received by an external X-ray detector. Due to the high rate of X-ray pulse events... It can characterize the frequency of radiative response events per unit time, while the unit pulse event rate obtained in step S2 enhances the expression. The electron mean free path and collision probability factors have been further introduced to weight the original pulse event rate based on the collision mechanism. This can serve as an equivalent characterization of electron collision intensity. Based on this, a mapping relationship is established between X-ray radiation response and electron collision process, transforming the detected X-ray statistics from simple signal characteristics into collision characterization parameters with physical meaning. Mapping calibration coefficients. It is used to characterize the combined effects of detector sensitivity, geometric arrangement, electrode materials and system gain on the conversion of electron collision intensity to X-ray response intensity, and can be obtained in advance through calibration tests under known vacuum conditions.

[0050] The expression for the mapping model between the X-ray generation mechanism and the electron collision process in this embodiment is as follows:

[0051] in, R x ( t () represents the X-ray pulse event rate per unit time. K The system parameters obtained through calibration experiments are related to the following factors: detector sensitivity, distance between the detector and the radiation source, atomic number of the material, and electron energy distribution. For example, for a CZT detector system, K It can be achieved by using a known vacuum level (e.g., 10). -3 The experimental calibration was obtained under typical experimental conditions. K The order of magnitude can be 10 -3 ~10 -1 .

[0052] The construction process of the inversion calculation formula is as follows: The essence of the change in vacuum degree is the change in the number density of residual gas molecules in the arc-extinguishing chamber; and the change in the number density of gas molecules will change the mean free path and collision probability of electrons in the gap, thereby affecting the X-ray pulse event rate and its enhancement expression. Therefore, the event rate can be enhanced first through a mapping model. This is transformed into equivalent physical quantities corresponding to electron collision processes. Combined with the relationship between mean free path and pressure in gas dynamics, a model is established that converts X-ray statistical characteristics into vacuum parameters. The inversion formula is as follows. This embodiment achieves a quantitative solution for vacuum degree through a progressive chain of "enhanced event rate - collision process - gas parameters". The inversion formula constructed in this way retains the accuracy advantage of X-ray detection and provides a clear physical basis for vacuum degree calculation.

[0053] The inversion in this embodiment yields the vacuum degree, specifically including the following steps: According to gas dynamics, the mean free path of electrons satisfies:

[0054] in, k Boltzmann's constant is used to describe the relationship between the thermal motion of gas molecules and temperature; its value is... ; T The thermodynamic temperature of the gas inside the arc-extinguishing chamber of a vacuum circuit breaker, expressed in K. d m The equivalent diameter of a gas molecule is used to characterize the collision cross section between gas molecules, and its value depends on the type of gas. p ( t () represents the degree of vacuum.

[0055] Electron at the open distance d The probability of at least one collision occurring within the area is P c :

[0056] Will Substitution P c ( t The vacuum degree can be obtained by inversion. p ( t The vacuum degree obtained by inversion p ( t The calculation formula for ) is as follows:

[0057] in, d The distance between the moving and stationary contacts of the arc-extinguishing chamber of a vacuum circuit breaker, in meters (m). An enhanced representation of the unit pulse event rate, used to characterize the X-ray pulse event rate after electron collision probability weighting; K These are the system parameters obtained through calibration experiments.

[0058] Step S4: Combining the slowly varying characteristics of the vacuum state, the vacuum degree result obtained by inversion is jointly corrected based on statistical stability and spatial response characteristics, thereby obtaining a stable vacuum degree result with spatial consistency correction. Specifically: Considering the large fluctuations in X-ray pulses and the potential for noise interference, as well as the potential spatial differences in X-ray signals measured at different locations, this embodiment corrects the vacuum degree results obtained through inversion.

[0059] Step S41: Calculate the average vacuum degree Average vacuum degree The calculation formula is as follows:

[0060] in, p ( t ) represents the vacuum degree obtained through inversion.

[0061] Step S42: Since the vacuum level of the vacuum circuit breaker's arc-extinguishing chamber will not change drastically during the experiment, it is excluded. p ( t The obvious data anomalies in the data are used to calculate the vacuum degree obtained by inversion. p ( t variance of ) oh i :

[0062] Based on the X-ray detector's response to the space radiation source, the radiation source here is the X-ray radiation region inside the vacuum circuit breaker's arc-extinguishing chamber, formed by collisions between electrons and electrode materials or residual gas molecules under applied voltage. The spatial response coefficient was calculated. Spatial response coefficient The calculation formula is as follows:

[0063] in, Indicates spatial location r The radiation source for the first i The contribution weights of each X-ray detector, inversion oh i The vacuum degree obtained by inversion p ( t The variance of ).

[0064] Step S43: Calculate the corrected vacuum degree. p s ( t Corrected vacuum level p s ( t The calculation formula for ) is as follows:

[0065] in, For spatial response coefficients,p ( t ) represents the vacuum degree obtained through inversion.

[0066] The specific embodiments described above further illustrate the technical problems, technical solutions, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are 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 vacuum degree of a circuit breaker based on electron collision radiation inversion, characterized in that, Includes the following steps: Step S1: Simultaneously collect X-ray pulse signals from multiple measuring points outside the vacuum circuit breaker arc extinguishing room, extract and parameterize the pulse events to obtain the time distribution characteristics reflecting electron collision behavior; Step S2: Establish a feature enhancement model based on electron collision probability; Step S3: Establish a mapping model between the X-ray generation mechanism and the electron collision process, and then invert the vacuum degree. Step S4: Perform a joint correction on the vacuum degree result obtained by inversion based on statistical stability and spatial response characteristics to obtain the corrected vacuum degree result.

2. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 1, characterized in that, In step S1, X-ray pulse signals are simultaneously acquired through multiple measuring points outside the vacuum circuit breaker arc extinguishing chamber, specifically including the following steps: Multiple X-ray detectors are arranged axially or radially outside the arc-extinguishing chamber of the vacuum circuit breaker. A voltage is applied across the moving and stationary contacts of the vacuum circuit breaker arc-extinguishing chamber at a given opening distance d. U Then, X-ray pulse signals were acquired to obtain multi-channel time series. X ( t The multi-channel time series X ( t The expression for ) is as follows: in, These are electrical pulses triggered by X-ray photons.

3. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 1, characterized in that, In step S1, the pulse events are extracted and parameterized to obtain the temporal distribution characteristics reflecting electron collision behavior, specifically including the following steps: Threshold discrimination and pulse detection were performed on the acquired X-ray pulse signals to extract pulse event sequences. E The pulse event sequence E The expression is as follows: in, t i For the first i The time of occurrence of each X-ray pulse A i This refers to the amplitude corresponding to the X-ray pulse; pass t i Obtain the X-ray pulse event rate per unit time R x ( t The X-ray pulse event rate per unit time R x ( t The expression for ) is as follows: in, For statistical time windows, t i For the first i The time of occurrence of each X-ray pulse t i+1 For the first i +1 X-ray pulse occurrence time, N x for Δt The number of X-ray pulses that occur within a given time period.

4. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 1, characterized in that, In step S2, establishing a feature enhancement model based on electron collision probability specifically includes the following steps: First, calculate the mean free path of the electron in statistical probability derived from multi-point X-rays. λ e The calculation formula is as follows: in, This represents the average time interval between adjacent X-ray pulse events; Statistical time window for each unit; This refers to the electron drift velocity; μ e Electron mobility; d The distance between the moving and stationary contacts in the arc-extinguishing chamber of a vacuum circuit breaker; U The voltage applied across the moving and stationary contacts of the vacuum circuit breaker arc-extinguishing chamber under the opening distance d condition; Then, a weighting function related to electron collisions is constructed. The weighting function related to electron collisions The expression is as follows: in, Let be the electron collision radiation efficiency coefficient; d The distance between the moving and stationary contacts in the arc-extinguishing chamber of a vacuum circuit breaker; Finally, the enhanced expression of unit impulse event rate was obtained. The enhanced expression of the unit impulse event rate The expression is as follows: in, R x ( t () represents the X-ray pulse event rate per unit time. This is a weighting function related to electron collisions.

5. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 1, characterized in that, The expression for the mapping model between the X-ray generation mechanism and the electron collision process in step S3 is as follows: in, R x ( t () represents the X-ray pulse event rate per unit time. K These are the system parameters obtained through calibration experiments. d The distance between the moving and stationary contacts in the arc-extinguishing chamber of a vacuum circuit breaker. λ e It is the mean free path of the electron.

6. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 1, characterized in that, In step S3, the vacuum degree is obtained by inversion, which specifically includes the following steps: Vacuum degree is obtained by inversion using gas dynamics relationships p ( t The vacuum degree obtained by inversion p ( t The calculation formula for ) is as follows: in, k Boltzmann's constant; T The thermodynamic temperature of the gas inside the arc-extinguishing chamber of a vacuum circuit breaker; d The opening distance between the moving and stationary contacts of the arc-extinguishing chamber of a vacuum circuit breaker; d m The equivalent diameter of a gas molecule; is an enhanced expression for the unit impulse event rate; K is a system parameter obtained through calibration experiments.

7. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 1, characterized in that, In step S4, the vacuum degree result obtained by inversion is jointly corrected based on statistical stability and spatial response characteristics to obtain the corrected vacuum degree result, which specifically includes the following steps: Step S41: Calculate the average vacuum degree ; Step S42: Calculate the vacuum degree obtained from the inversion. p ( t variance of ) ω i By combining the response of the X-ray detector to the space radiation source, the spatial response coefficient was calculated. ; Step S43: Calculate the corrected vacuum degree. p s ( t ).

8. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 7, characterized in that, The average vacuum degree The calculation formula is as follows: in, p ( t ) represents the vacuum degree obtained through inversion.

9. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 8, characterized in that, The spatial response coefficient The calculation formula is as follows: in, Indicates spatial location r The contribution weight of the radiation source to the i-th X-ray detector. ω i The vacuum degree obtained by inversion p ( t The variance of ).

10. The circuit breaker vacuum degree detection method based on electron collision radiation inversion according to claim 9, characterized in that, The formula for calculating the corrected vacuum degree ps(t) is as follows: in, For spatial response coefficients, p ( t ) represents the vacuum degree obtained through inversion.

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