Screening method and device for detecting optimal modification configuration of pd-ga nnts for detecting switchgear fault characteristic gas

Abstract

A screening method and device for detecting the optimal modified configuration of Pd-GaNNTs for switch cabinet fault characteristic gas, the method comprising: constructing multiple candidate modified configurations of Pd-GaNNTs; determining multiple characteristic parameters of each candidate modified configuration based on DFT, obtaining a comprehensive index of thermodynamic stability of the corresponding candidate modified configuration based on the multiple characteristic parameters, and screening out configurations with a comprehensive index of thermodynamic stability greater than a preset threshold; calculating the adsorption performance parameters of each screened configuration for multiple characteristic gases of switch cabinet faults, and then calculating the corresponding gas discrimination index; determining the dynamic response-recovery equilibrium index of each screened configuration at a preset working temperature; for each screened configuration, determining a comprehensive score according to the comprehensive index of thermodynamic stability, the discrimination index and the equilibrium index, and selecting the optimal modified configuration. The present application can screen the optimal configuration from multiple Pd-GaNNTs configurations, which has high sensitivity, high selectivity and can be quickly desorbed and recovered at room temperature.

Description

Technical Field

[0001] This invention relates to the field of switchgear fault characteristic gas detection technology, specifically to a method and apparatus for screening the optimal modification configuration of palladium-modified gallium nitride nanotubes (Pd-GaNNTs) for detecting switchgear fault characteristic gases. Background Technology

[0002] In the power transmission and distribution system, switchgear, as a key piece of equipment, undertakes the core functions of circuit switching, fault isolation, and power distribution. Operating under high voltage and variable load conditions for extended periods, it is prone to partial discharge due to issues such as metal burrs left over from manufacturing, air gaps caused by transportation vibrations, and aging of insulation materials. The high energy density generated by partial discharge leads to the decomposition of air inside the switchgear, producing characteristic gases such as CO, NO, O3, and N2O4. These gases not only accelerate the aging of the insulation medium and corrode metal components, leading to a decrease in the insulation level of the switchgear, but can also cause serious accidents such as short circuits and explosions. Statistics show that switchgear failures caused by partial discharge account for more than 35% of all power equipment failures, resulting in economic losses exceeding 100 million yuan annually.

[0003] The internal structure of switchgear is complex, and fault types are diverse. Visual inspection and conventional testing methods alone are often insufficient to accurately determine the specific nature of the fault. However, detection methods based on fault-characteristic gases can directly reflect the development level of partial discharge by analyzing gas composition and concentration, offering advantages such as strong anti-interference capabilities and high detection accuracy. Traditional gas sensors include electrochemical sensors and metal oxide sensors. Electrochemical sensors rely on the redox reaction at the electrode / electrolyte interface to generate a Faraday current, quantifying gas concentration by measuring current or potential changes; however, their carrier transport efficiency is relatively low. Metal oxide sensors (such as SnO2, ZnO, WO3, etc.) detect gas based on the resistance change caused by gas adsorption on the surface of n-type or p-type metal oxide semiconductors, typically requiring heating to 200-400℃ to accelerate the surface reaction. While these traditional gas sensors can detect some gases, they suffer from low sensitivity (only reaching the ppm level), poor selectivity (susceptible to cross-interference from other gases), slow response speed (>5 minutes), and high operating temperature, failing to meet the online monitoring needs of complex gas environments within switchgear.

[0004] Currently, there are studies using intrinsic GaNNTs as gas-sensitive materials. As a one-dimensional wide-bandgap semiconductor, intrinsic GaNNTs have a theoretical response time in the millisecond to second range. Their high intrinsic bandwidth also reduces interference from thermally excited carriers, which is beneficial for achieving high-speed detection at room temperature. However, intrinsic GaNNTs have weak adsorption capacity for inert characteristic gases such as CO and NO, and insufficient "material-gas" interaction strength, resulting in weak gas-sensitive response signals, making them unsuitable for the complex gas environment detection requirements of switchgear. Summary of the Invention To address the problems of existing technologies, this invention proposes a method and apparatus for screening the optimal Pd-GaNNTs modification configuration for detecting characteristic gases in switchgear faults. The optimal configuration is selected from various palladium modification configurations, taking into account high sensitivity, high selectivity, and rapid desorption recovery at room temperature, thereby achieving highly selective detection of four mixed gases, CO, NO, O3, and N2O4, at room temperature.

[0005] According to a first aspect of the present invention, a method for screening the optimal modification configuration of Pd-GaNNTs for detecting characteristic gases in switchgear faults is provided. The method includes the following steps: Multiple candidate modification configurations for palladium-modified gallium nitride nanotubes (Pd-GaNNTs) were constructed, including palladium single-atom doping configuration, palladium dimer cluster doping configuration, palladium trimer cluster doping configuration, and palladium tetramer cluster doping configuration. Based on DFT, multiple characteristic parameters of each candidate modification configuration are determined. Each characteristic parameter is compared with the corresponding characteristic parameter reference value of the corresponding candidate modification configuration and weighted and fused to obtain the comprehensive thermodynamic stability index of the corresponding candidate modification configuration. Configurations with a comprehensive thermodynamic stability index greater than a preset threshold are selected. The adsorption performance parameters of each selected configuration for multiple characteristic gases of switchgear faults are calculated respectively. Based on the adsorption performance parameters, the discrimination index of the selectivity of multiple characteristic gases for each selected configuration is calculated. The discrimination index is used to measure the degree of difference in the response of the configuration to the multiple characteristic gases. Determine the dynamic response-recovery balance index of each selected configuration at a preset operating temperature. The balance index is used to measure the degree of matching between the response rate of the configuration to the target gas and its desorption recovery capability. For each selected configuration, a comprehensive score is determined based on the thermodynamic stability index, the discrimination index, and the equilibrium index. The configuration that meets the predetermined conditions is selected as the optimal modified configuration.

[0006] Furthermore, the plurality of characteristic parameters include binding energy. Formation energy The orbital interaction strength between palladium and neighboring atoms and the electronic state density of palladium near the Fermi level ; The comprehensive thermodynamic stability index is obtained by the following formula:

[0007] in, α is the comprehensive index of thermodynamic stability of the current configuration; α, β, γ, and δ are the weighting coefficients corresponding to each characteristic parameter, and α+β+γ+δ=1; , , , These are the reference values ​​for the corresponding characteristic parameters in all candidate configurations.

[0008] Furthermore, the various characteristic gases include CO, NO, O3, and N2O4; The adsorption performance parameters include adsorption energy. Charge transfer amount Change rate of band gap before and after adsorption The rate of change of the total density of states of the material before and after adsorption at the Fermi level .

[0009] Furthermore, the discrimination index is obtained by the following formula:

[0010] in, This is the discrimination index for the current configuration, where n=4 represents the number of gas species. and The first i species and first j The adsorption performance vector corresponding to each gas, ∥ ∥ is the vector norm. The larger the value, the greater the degree of difference in the response of the corresponding configuration to the four gases.

[0011] Furthermore, the parameter components in the adsorption performance vector are normalized using Min-Max before calculation. The normalization formula is as follows:

[0012] in, For the first i gas, the first m The original values ​​of the adsorption parameters; and Each of the gases in the th m Minimum and maximum values ​​of the parameters; These are the normalized parameter components.

[0013] Furthermore, the balance index is obtained by the following formula:

[0014] in, This is the balance index for the current configuration; and Let be the theoretical response time and theoretical desorption time of the k-th gas, respectively, and we have:

[0015]

[0016] in, This is the initial adsorption distance. To balance the adsorption distance, The natural vibration frequency of the atom, The adsorption activation energy, Boltzmann's constant, T To preset the operating temperature, Let be Planck's constant. This is the desorption energy.

[0017] Furthermore, the comprehensive score is obtained by the following formula:

[0018]

[0019] in, This is the overall score for the current configuration; , , These are the comprehensive thermodynamic stability index, the distinguishability index, and the equilibrium index for the current configuration, respectively. , , These are the weight coefficients for each item; , , These are the maximum values ​​of the thermodynamic stability comprehensive index and the maximum value of the discrimination index among all configurations that meet the preset conditions. The maximum value.

[0020] Furthermore, the optimal modification configuration is gallium nitride nanotubes modified with palladium trimer clusters, wherein the palladium trimers are vertically anchored to the active sites of the pores on the surface of the gallium nitride nanotubes in a spatial triangular configuration, and the adsorption energies of the four gases for this optimal modification configuration are ranked as N2O4>CO>O3>NO.

[0021] According to a second aspect of the present invention, a screening device for detecting the optimal modified configuration of Pd-GaNNTs for detecting characteristic gases of switchgear faults is provided. This device utilizes the method described in the first aspect of the present invention, comprising: The module is used to construct multiple candidate modification configurations of palladium-modified gallium nitride nanotubes (Pd-GaNNTs), wherein the multiple candidate modification configurations include at least palladium single-atom doping configuration, palladium dimer cluster doping configuration, palladium trimer cluster doping configuration, and palladium tetramer cluster doping configuration; The stability index determination module is used to determine multiple characteristic parameters for each candidate modification configuration based on DFT, compare each characteristic parameter with the corresponding characteristic parameter reference value of the corresponding candidate modification configuration and weight and fuse them to obtain the comprehensive thermodynamic stability index of the corresponding candidate modification configuration, and screen out the configurations with a comprehensive thermodynamic stability index greater than a preset threshold. The discrimination index determination module is used to calculate the adsorption performance parameters of each selected configuration for multiple characteristic gases of switchgear faults, and calculate the discrimination index of the selectivity of multiple characteristic gases for each selected configuration based on the adsorption performance parameters. The discrimination index is used to measure the degree of difference in the response of the configuration to the multiple characteristic gases. The balance index determination module is used to determine the dynamic response-recovery balance index of each selected configuration at a preset operating temperature. The balance index is used to measure the degree of matching between the response rate of the configuration to the target gas and its desorption recovery capability. The selection module is used to determine a comprehensive score for each selected configuration based on the thermodynamic stability comprehensive index, the discrimination index, and the equilibrium index, and select the configuration whose comprehensive score meets the predetermined conditions as the optimal modified configuration.

[0022] According to a third aspect of the present invention, a terminal is provided. The terminal includes a processor and a storage medium; The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to the first aspect of the invention.

[0023] Compared with the prior art, the present invention can produce the following beneficial technical effects: 1. By constructing a comprehensive candidate modification configuration library covering palladium single atoms and various cluster sizes, and extracting multiple characteristic parameters such as binding energy, formation energy, orbital interaction strength, and electronic density of states at the Fermi level based on density functional theory, a comprehensive thermodynamic stability index was obtained and initial screening was completed. This approach eliminates reliance on a single indicator and comprehensively evaluates the stability of doped configurations from the perspective of atomic orbital hybridization, fundamentally solving the problem of weak adsorption capacity of intrinsic gallium nitride nanotubes for characteristic gases in switchgear faults.

[0024] 2. By calculating the adsorption energy, charge transfer, bandgap change rate, and total density of states change rate at the Fermi level for each candidate configuration for four fault characteristic gases (CO, NO, O3, and N2O4), and combining these adsorption performance parameters into a vector, a multi-gas selectivity discrimination index is calculated. This quantifies the degree of difference in the material's response to different gases, overcoming the core defects of traditional gas sensors, such as severe cross-interference and poor selectivity in mixed gas environments. Simultaneously, this discrimination index ensures that the optimal configuration selected clearly ranks the adsorption energies and conductivity effects for the four gases, providing a physical basis for subsequent gas identification. 3. By calculating the dynamic response-recovery balance index (i.e., the average ratio of response time to desorption time) of each candidate configuration at a preset operating temperature, the screening process achieves an engineering balance between detection sensitivity and sensor reusability. This solves the problem of traditional screening methods unilaterally pursuing high adsorption energy, leading to desorption difficulties and the inability of sensors to perform long-term online monitoring. 4. By weighting and comprehensively scoring the thermodynamic stability index, multi-gas selectivity discrimination index, and dynamic response-recovery balance index, and selecting the configuration with the highest score as the optimal modified configuration, the screening results achieve the optimal balance in the three dimensions of stability, selectivity, and reversibility. The resulting optimal Pd3-GaNNTs configuration can achieve ppb-level high-sensitivity detection, fast response (less than 60 seconds), and good recovery characteristics for four fault characteristic gases of switchgear at room temperature, providing a reliable theoretical basis and technical support for online monitoring of partial discharge in switchgear. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating the screening method for the optimal modification configuration of Pd-GaNNTs used in detecting characteristic gases of switchgear faults according to the present invention. Figure 2 A schematic diagram showing Pd atoms and modification sites of different Pd clusters; Figure 3 The optimal adsorption configurations of CO, NO, O3, and N2O4 on the Pd2-GaNNTs surface are shown. Figure 4 The optimal adsorption configurations of CO, NO, O3, and N2O4 on the Pd3-GaNNTs surface are shown. Figure 5 TDOS and PDOS images of CO, NO, O3, and N2O4 adsorbed on Pd2-GaNNTs; Figure 6 TDOS and PDOS images of CO, NO, O3, and N2O4 adsorbed on Pd3-GaNNTs. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, other embodiments obtained by those skilled in the art without creative effort are all within the protection scope of this invention.

[0027] It should be noted that in this invention, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0028] Example 1 This embodiment provides a method for screening the optimal modification configuration of palladium-modified gallium nitride nanotubes (Pd-GaNNTs) for detecting characteristic gases of switchgear faults. Specifically, the characteristic gases of switchgear faults include carbon monoxide (CO), nitric oxide (NO), ozone (O3), and dinitrogen tetroxide (N2O4). These four gases are the main products of air decomposition during partial discharge inside the switchgear, and their concentration and proportion can reflect the severity of the discharge. This method is based on first-principles density functional theory (DFT) and systematically screens the palladium modification configuration with the best overall performance from a variety of candidate modification configurations through multi-dimensional weighted fusion, selective discrimination evaluation, and dynamic equilibrium analysis.

[0029] Specifically, such as Figure 1 The method includes the following steps: S1. Construct multiple candidate modification configurations for palladium-modified gallium nitride nanotubes (Pd-GaNNTs), including palladium single-atom doping configuration, palladium dimer cluster doping configuration, palladium trimer cluster doping configuration, and palladium tetramer cluster doping configuration.

[0030] Specifically, a supercell model of intrinsic gallium nitride nanotubes (GaNNTs) was first constructed using Materials Studio software. The model has dimensions of 25 Å × 25 Å × 12.8 Å and contains 48 gallium (Ga) atoms and 48 nitrogen (N) atoms, forming a network structure dominated by six-membered rings, with a Ga-N bond length of 1.850 Å. To avoid interactions between adjacent periodic units, the vacuum layer thickness was set to 20 Å.

[0031] Next, as Figure 2 As shown, based on intrinsic GaNNTs, four candidate modification configurations were designed, including palladium single-atom doping configuration, palladium dimer cluster doping configuration, palladium trimer cluster doping configuration, and palladium tetramer cluster doping configuration, to cover the complete range from single atoms to clusters of different sizes, and to avoid missing better options due to configuration omissions.

[0032] Palladium single-atom doped configuration (Pd1) In GaNNTs, individual Pd atoms are doped vertically at the active sites of the GaNNT surface pores, forming a pyramid structure. They form three chemical bonds with the surrounding N and Ga atoms, i.e., one Pd atom. N-bonds and two Pd bonds Ga key.

[0033] Palladium dimer cluster doping configuration (Pd2) In GaNNTs, two Pd atoms form clusters and are arranged in a horizontal parallel orientation in the pores of the GaNNT surface. The Pd bond length is approximately 2.54 Å, and the two Pd atoms form 3 and 4 chemical bonds with the substrate, respectively.

[0034] Palladium trimer cluster doped configuration (Pd3) In GaNNTs, three Pd atoms form a spatial triangular configuration and are vertically anchored in the active region of the GaNNT surface pores. All three Pd atoms are bonded to the substrate N atoms to form cooperative active sites.

[0035] Palladium tetramer cluster doping configuration (Pd4) In GaNNTs, four Pd atoms form approximately tetrahedral clusters loaded on the GaNNTs surface. After optimization, the tetrahedrons are distorted, and some Pd atoms are affected. Pd bond elongation.

[0036] Among the four configurations mentioned above, Pd3-GaNNTs have the most negative binding energy (-3.82 eV) and formation energy (-3.05 eV), which preliminarily indicates that they have the best thermodynamic stability.

[0037] S2. Based on DFT, determine multiple characteristic parameters for each candidate modification configuration. Compare and weightedly fuse each characteristic parameter with the corresponding characteristic parameter reference value of the candidate modification configuration to obtain the comprehensive thermodynamic stability index of the corresponding candidate modification configuration. Select configurations with a comprehensive thermodynamic stability index greater than a preset threshold.

[0038] This step begins with setting the DFT (Density Functional Theory) calculation parameters. All DFT calculations are performed within the Dmol³ module, and all models use uniform calculation parameters to avoid interference from parameter variables and ensure the comparability of performance data across different adsorption configurations.

[0039] The electronic structure-related calculation settings are as follows: the PBE exchange-correlated functional under the generalized gradient approximation (GGA) is selected; the basis set type is set to DNP dual numerical polarization basis set; the spin-constrained mode is enabled in the calculation process, and the k-point grid sampling in the Brillouin zone is set to 1×1×2.

[0040] During the geometric optimization phase, a stringent convergence criterion was set: the total energy convergence threshold of the system was 1.0 × 10⁻⁶. -5 The maximum stress convergence threshold for Ha atoms is 2.0 × 10⁻⁶. - ³ Ha / Å, the maximum atomic displacement convergence threshold is 5.0 × 10⁻⁶. - ³ Å. Furthermore, to accurately describe the weak interactions between molecules and the substrate, Grimme DFT-D2 empirical dispersion corrections were introduced for all computational systems.

[0041] Next, multiple feature parameters are extracted for each candidate configuration, including: binding energy. Formation energy Orbital interaction strength ICOH and Fermi level Disposal wave state density PDOS.

[0042] Binding energy The bonding strength between the dopant atoms and the substrate is reflected by the following formula:

[0043] in, The total energy of the doped system, The intrinsic basis energy, ν is the energy of a single Pd atom, and m is the number of Pd atoms doped with it. Binding energy. The more negative the value, the stronger the bonding of the doped configuration and the higher the stability of the system.

[0044] Formation energy The thermodynamic stability of the doped system is reflected by the following formula:

[0045] in, The chemical potential of Pd atoms, formation energy The more negative the value, the higher the thermodynamic stability of the system and the easier it is to form a doped configuration.

[0046] The orbital interaction strength ICOHP is the Hamiltonian population integral of the crystal orbitals, with the integration range from 5 eV below the Fermi level to 2 eV above the Fermi level. It takes a negative value, and the larger the value, the stronger the covalent bonding between Pd and the surrounding N and Ga atoms.

[0047] Fermi level The density of states (PDOS) of the disposal wave is the density of states of the 4d orbitals of the Pd atom at the Fermi level, reflecting the contribution of the doped atom to the conductivity.

[0048] The calculated values ​​of the characteristic parameters for the four configurations are shown in Table 1.

[0049] Table 1

[0050] Furthermore, a weighted fusion method is used to calculate the comprehensive thermodynamic stability index. The calculation method is as follows:

[0051] in, α is the comprehensive index of thermodynamic stability of the current configuration; α, β, γ, and δ are the weighting coefficients corresponding to each characteristic parameter, and α+β+γ+δ=1; , , , These are reference values ​​for the corresponding characteristic parameters in all candidate configurations. Specifically, each of the above reference values ​​is taken as the optimal value among all candidate configurations: Take the one with the largest absolute value (-3.82 eV, corresponding to Pd3). Take the one with the smallest absolute value (3.05 eV, corresponding to Pd3). Take the one with the largest absolute value (-6.54 eV, corresponding to Pd3). The maximum value (0.71, corresponding to Pd3) is taken. The weighting coefficients can be determined using the analytic hierarchy process. In this embodiment, α=0.3, β=0.2, γ=0.4, and δ=0.1 are taken to highlight the dominant role of orbital interactions and binding energy.

[0052] The comprehensive thermodynamic stability index of Pd1 to Pd4 was calculated. The values ​​are 0.72, 0.84, 1.00, and 0.91 respectively. A preset threshold of 0.80 is set to filter out... Configurations with a value >0.80, namely Pd2, Pd3, and Pd4, will proceed to the next round of screening.

[0053] In this step, the stability of the doped configuration is evaluated more comprehensively by using multi-parameter weighted fusion rather than a single index (such as comparing only binding energy). At the same time, by introducing electronic structure parameters such as ICOHP and PDOS, the screening results have clear physical meaning, and the threshold setting can quickly eliminate unstable candidate configurations, reducing the amount of subsequent calculations.

[0054] S3. Calculate the adsorption performance parameters of each selected configuration for multiple characteristic gases of switchgear faults. Based on the adsorption performance parameters, calculate the discrimination index of the selectivity of multiple characteristic gases for each selected configuration. The discrimination index is used to measure the degree of difference in the response of the configuration to the multiple characteristic gases.

[0055] In this step, the adsorption performance parameters are first calculated. Specifically, for the three selected configurations (Pd2, Pd3, and Pd4), their adsorption performance parameters for four characteristic failure gases (CO, NO, O3, and N2O4) are calculated. Each gas molecule is initially placed approximately 2.5 Å above the Pd active site, and a stable adsorption configuration is obtained through geometry optimization, as shown below. Figures 2-4 As shown.

[0056] Taking Pd3-GaNNTs as an example, the adsorption characteristics of the four gases are as follows: CO: linear adsorption behavior, with C atoms oriented towards Pd atoms for bonding, adsorption distance of 1.884 Å. The O bond length slightly elongates from 1.128 Å in the free state to 1.156 Å. Adsorption energy = -2.176 eV, charge transfer amount = +0.222 e, electrons are transferred from CO to the substrate material. The rate of change of the band gap before and after adsorption. = +19.1%, the band gap increases, and the rate of change of the total density of states at the Fermi level. = +8%.

[0057] NO: Bidentate adsorption state, N and O atoms are bonded to Pd atoms respectively, Pd N bond length 2.035 Å, Pd The O bond length is 2.212 Å. Adsorption energy... = -1.106 eV, charge transfer amount = -0.182 e, electrons transfer from the substrate to NO. Rate of change of band gap before and after adsorption. = -73.3%, the rate of change of the total density of states at the Fermi level = +15%.

[0058] O3: Bending configuration, monodentate adsorption attitude, adsorption distance 1.978 Å. Adsorption energy. = -1.548 eV, charge transfer amount = -0.255 e. Rate of change of band gap before and after adsorption. = -79.6%, the band gap decreases from 2.244 eV to 0.458 eV. Rate of change of total density of states at the Fermi level. = +28%.

[0059] N₂O₄: Decomposition adsorption mode. N₂O₄ decomposes into two NO₂ molecules, with only N atoms bonded to Pd atoms. The adsorption distance is 2.000 Å. Adsorption energy. = -2.719 eV, charge transfer amount = -0.384 e, the rate of change of the band gap before and after adsorption = -31.0%, the rate of change of the total density of states at the Fermi level = +45%.

[0060] The adsorption stability of the four gases on Pd3-GaNNTs was ranked as follows: N2O4 > CO > O3 > NO, consistent with the adsorption energy. The effect on conductivity was ranked as follows: O3 > NO > N2O4 > CO, with O3 showing the largest bandgap decrease after adsorption, resulting in the most significant decrease in electrical resistance (approximately 60%).

[0061] Meanwhile, to reveal the interaction mechanism between the four gases and Pd3-GaNNTs, partial density of states (PDOS) analysis was performed on the adsorption system, focusing on the hybridization between the 4d orbitals of Pd atoms in the clusters and the 2p orbitals of key atoms in the gas molecules. Figure 5 As shown, the TDOS and PDOS images of different gas adsorption systems exhibit significant differences. The following analysis combines... Figure 5 A detailed analysis was conducted on each gas adsorption system.

[0062] (1) N2O4 adsorption: N2O4 decomposes into two NO2 molecules, with only the N atom bonding with Pd. In the range of -8 eV to -2 eV, the Pd-4d orbital and the NO2-2p orbital undergo strong hybridization, forming three distinct hybridization peaks, with the peak height increased by 32% compared to pure Pd3-GaNNTs; simultaneously, 0.384 e charge is transferred from the gas to the substrate. Strong chemisorption corresponds to the maximum adsorption energy (-2.719 eV).

[0063] (2) O3 adsorption: O3 is adsorbed in a monodentate manner. The Pd-4d orbital and the O3-π* orbital hybridize in the range of -7 eV to -1 eV, increasing the peak height by 25%. O3 transfers 0.255 e electrons to the substrate, which is a moderate chemisorption (-1.548 eV). After O3 adsorption, the band gap decreases from 2.244 eV to 0.458 eV (a decrease of 79.6%), and the conductivity is improved most significantly.

[0064] (3) NO adsorption: NO is adsorbed in a bidentate manner. The Pd-4d orbital and the NO-π orbital undergo weak hybridization in the range of -6 eV to 0 eV, and the peak height is only increased by 18%. NO gains 0.182 e electrons from the substrate (electron acceptor), and the band gap decreases to 0.599 eV, but the increase in conductivity is less than that of O3.

[0065] (4) CO adsorption: CO adsorbs linearly, with only weak hybridization at -5 eV, and the peak height increases by only 10%. CO transfers 0.222 e electrons to the substrate, but the band gap increases to 2.672 eV (an increase of 19.1%), resulting in the smallest improvement in conductivity.

[0066] The PDOS analysis described above reveals the physical basis for the differentiated responses of Pd3-GaNNTs to the four gases, providing mechanistic support for the discrimination index. It should be noted that the PDOS analysis is also applicable to other candidate configurations such as Pd2 and Pd4. By comparing the hybridization intensity and mode differences of different configurations, the physical rationality of the "discrimination index" ranking can be verified at the electronic structure level. Figure 5 The TDOS and PDOS images quantitatively demonstrated the changes in electronic structure of different adsorption systems, which were highly consistent with the above analysis results.

[0067] To quantify the degree of difference in response of each configuration to the four gases, an adsorption performance vector Vi (i=1~4 corresponding to CO, NO, O3, N2O4 respectively) is constructed, with each vector containing four parameters ( , , , First, Min-Max normalization is performed to eliminate the influence of dimensions:

[0068] in, For the first i gas, the first m The original values ​​of the adsorption parameters; and Each of the gases in the th m Minimum and maximum values ​​of the parameters; These are the normalized parameter components.

[0069] Then, calculate the discrimination index:

[0070] in, This is the discrimination index for the current configuration, with a value range of (0,1]. The larger the value, the greater the degree of difference in the response of the corresponding configuration to the four gases; n=4 represents the number of gas species. and The first i species and first j The adsorption performance vector corresponding to each gas, ∥ ∥ represents the vector norm.

[0071] By calculating the distinguishability index of each configuration, it can be seen that: Pd2-GaNNTs =0.47, Pd2-GaNNTs of Pd3-GaNNTs =0.82, and Pd2-GaNNTs of Pd4-GaNNTs =0.61. The discrimination index of Pd3 is significantly higher than the other two, indicating that it has the best recognition ability for the four gases.

[0072] In this step, the abstract concept of multi-gas selectivity is quantified into a comparable mathematical index by using a "discrimination index" based on the adsorption performance vector, overcoming the shortcomings of traditional methods that only focus on the adsorption energy of a single gas and ignore the ability to distinguish between gases.

[0073] S4. Determine the dynamic response-recovery balance index of each selected configuration at a preset operating temperature. The balance index is used to measure the degree of matching between the response speed of the configuration to the target gas and its desorption recovery capability.

[0074] First, the response time is calculated using the charge transfer rate theory, and the desorption time is calculated using the transition state theory. The specific formulas are as follows:

[0075]

[0076] in, and These are the theoretical response time and theoretical desorption time for the k-th gas, respectively. The initial adsorption distance is set to 5.0 Å. To balance the adsorption distance, it was obtained from the optimized configuration; Let be the natural vibrational frequency of the atom, taken as 1.0 × 10¹² s. - ¹; Let |E| be the adsorption activation energy, approximately taken as |E|. ads | / 2; Let be the Boltzmann constant, taken as 8.617 × 10⁻⁶. - 5 eV / K; T To set the preset operating temperature, this embodiment uses 300K; Let be Planck's constant, taken as 4.1357 × 10⁻⁶. - ¹ 5 eV·s; For the desorption energy, take |E ads |

[0077] Next, the equilibrium index is calculated based on the theoretical response time and theoretical desorption time:

[0078] in, This is the balance index for the current configuration, with an ideal value of 1, indicating that the response speed and recovery capability are optimally matched. If... If the value is much less than 1, desorption is too fast, and the response signal is not easy to capture; if the value is much greater than 1, desorption is too slow, and the sensor has poor reusability.

[0079] Preset operating temperature T The calculation results at =300 show that Pd2-GaNNTs =0.23, Pd3-GaNNTs =0.86, Pd4-GaNNTs =2.41. It can be seen that Pd3... The value closest to 1 indicates that it achieves the best balance between response speed and recovery ability. Pd4 has excessively strong adsorption, especially for N2O4 with an adsorption energy of -2.98 eV, resulting in a long desorption time, which is not conducive to repeated use of the sensor.

[0080] In this step, by introducing a dynamic response-recovery equilibrium index, it can be ensured that the selected configuration is not only sensitive but also has good desorption characteristics, making it suitable for practical online monitoring.

[0081] S5. For each selected configuration, a comprehensive score is determined based on the thermodynamic stability index, the discrimination index, and the equilibrium index. The configuration with the comprehensive score that meets the predetermined conditions is selected as the optimal modified configuration.

[0082] For the three configurations (Pd2, Pd3, Pd4) selected in steps S2 to S4, the comprehensive score is calculated using the following formula:

[0083]

[0084] in, This is the overall score for the current configuration; , , These are the comprehensive thermodynamic stability index, the distinguishability index, and the equilibrium index for the current configuration, respectively. , , These are the weighting coefficients for each item. In this embodiment, we take... =0.2、 =0.6、 =0.2; , , These are the maximum values ​​of the thermodynamic stability comprehensive index and the maximum value of the discrimination index among all configurations that meet the preset conditions. The maximum value. The closer it is to 1, the more ideal it is.

[0085] Table 2 shows the calculation results of the comprehensive score for each configuration.

[0086] Table 2

[0087] It can be seen that Pd3 GaNNTs' overall score =0.97, significantly higher than Pd2. 0.56 GaNNTs and Pd4 With a GaNNT content of 0.64, the optimal modified configuration was therefore determined as the best modification configuration for detecting characteristic gases in switchgear faults. This optimal modified configuration has the following characteristics: Palladium trimers are vertically anchored to the active sites in the pores of gallium nitride nanotubes in a spatial triangular configuration. The adsorption energies of the four gases are ranked as follows: N2O4 (-2.719 eV) > CO (-2.176 eV) > O3 (-1.548 eV) > NO (-1.106 eV). After O3 adsorption, the band gap of the system decreased to 0.458 eV, falling within the range of 0.4~0.5 eV; The theoretical recovery time for N2O4 at room temperature is approximately 320 s, which meets the requirements for practical applications.

[0088] In addition, to verify the structural stability of the optimal configuration under operating temperature, Pd3 Molecular dynamics simulations were performed on the GaNNT configuration. At 300 K, an NVT ensemble was used to simulate Pd³-GaNNTs for 10 ps with a time step of 1 fs. The calculated root mean square displacement (RMSD) showed that the RMSD of all atoms was less than 0.45 Å, indicating that the structure remained intact and no Pd cluster desorption or aggregation occurred, demonstrating that this configuration possesses good thermodynamic stability at room temperature.

[0089] In this step, a weighted comprehensive score is used to quantify the three dimensions of thermodynamic stability, multi-gas selectivity, and dynamic equilibrium in a unified manner, thus eliminating the one-sidedness of evaluation by a single index.

[0090] Through the method described in this embodiment, the present invention successfully determined Pd3-GaNNTs as the optimal modification configuration. It should be noted that the screening method provided by the present invention not only provides the optimal Pd-modified GaNNTs configuration for the detection of characteristic gases in switchgear faults, but also provides a general theoretical framework for the configuration optimization of other gas-sensitive material systems, possessing significant academic value and promising industrial application prospects.

[0091] This configuration can be used to prepare gas sensors for switchgear fault characteristics. Specifically, Pd3 clusters can be loaded onto the surface of GaNNTs by hydrothermal synthesis or chemical vapor deposition, and the resistance change can be converted into an electrical signal output through the electrode structure.

[0092] Example 2 This embodiment provides a screening device for the optimal modification configuration of Pd-GaNNTs for detecting characteristic gases in switchgear faults, utilizing the method described in Embodiment 1. The device includes: a construction module, a stability index determination module, a discrimination index determination module, a balance index determination module, and a selection module.

[0093] The building module is used to construct multiple candidate modification configurations of palladium-modified gallium nitride nanotubes (Pd-GaNNTs). The multiple candidate modification configurations include at least palladium single-atom doping configuration, palladium dimer cluster doping configuration, palladium trimer cluster doping configuration, and palladium tetramer cluster doping configuration. The stability index determination module is used to determine multiple characteristic parameters for each candidate modification configuration based on DFT. Each characteristic parameter is compared with the corresponding characteristic parameter reference value of the corresponding candidate modification configuration and weighted and fused to obtain the comprehensive thermodynamic stability index of the corresponding candidate modification configuration. Configurations with a comprehensive thermodynamic stability index greater than a preset threshold are selected. The discrimination index determination module is used to calculate the adsorption performance parameters of each selected configuration for multiple characteristic gases of switchgear faults, and calculate the discrimination index of the selectivity of multiple characteristic gases for each selected configuration based on the adsorption performance parameters. The discrimination index is used to measure the degree of difference in the response of the configuration to the multiple characteristic gases. The balance index determination module is used to determine the dynamic response-recovery balance index of each selected configuration at a preset operating temperature. The balance index is used to measure the degree of matching between the response rate of the configuration to the target gas and its desorption recovery capability. The selection module is used to determine a comprehensive score for each selected configuration based on the thermodynamic stability index, the discrimination index, and the equilibrium index, and select the configuration whose comprehensive score meets the predetermined conditions as the optimal modified configuration.

[0094] Example 3 This embodiment provides a computer-readable storage medium. The computer-readable storage medium stores a program that, when executed by a processor, implements the steps in the data-driven transformer area line loss quantization method as described in Embodiment 1 of this invention.

[0095] The detailed steps are the same as those of the data-driven transformer area line loss quantification method provided in Example 1, and will not be repeated here.

[0096] This disclosure can be a system, method, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of this disclosure.

[0097] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example—but not limited to—electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination of the foregoing. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0098] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0099] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0100] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A method for screening the optimal modification configuration of Pd-GaNNTs for detecting characteristic gases in switchgear faults, characterized in that, Includes the following steps: Multiple candidate modification configurations for palladium-modified gallium nitride nanotubes (Pd-GaNNTs) were constructed, including palladium single-atom doping configuration, palladium dimer cluster doping configuration, palladium trimer cluster doping configuration, and palladium tetramer cluster doping configuration. Based on DFT, multiple characteristic parameters of each candidate modification configuration are determined. Each characteristic parameter is compared with the corresponding characteristic parameter reference value of the corresponding candidate modification configuration and weighted and fused to obtain the comprehensive thermodynamic stability index of the corresponding candidate modification configuration. Configurations with a comprehensive thermodynamic stability index greater than a preset threshold are selected. The adsorption performance parameters of each selected configuration for multiple characteristic gases of switchgear faults are calculated respectively. Based on the adsorption performance parameters, the discrimination index of the selectivity of multiple characteristic gases for each selected configuration is calculated. The discrimination index is used to measure the degree of difference in the response of the configuration to the multiple characteristic gases. Determine the dynamic response-recovery balance index of each selected configuration at a preset operating temperature. The balance index is used to measure the degree of matching between the response rate of the configuration to the target gas and its desorption recovery capability. For each selected configuration, a comprehensive score is determined based on the thermodynamic stability index, the discrimination index, and the equilibrium index. The configuration that meets the predetermined conditions is selected as the optimal modified configuration.

2. The screening method according to claim 1, characterized in that, The multiple characteristic parameters include binding energy. Formation energy The orbital interaction strength between palladium and neighboring atoms and the electronic state density of palladium near the Fermi level ; The comprehensive thermodynamic stability index is obtained by the following formula: in, α is the comprehensive index of thermodynamic stability of the current configuration; α, β, γ, and δ are the weighting coefficients corresponding to each characteristic parameter, and α+β+γ+δ=1; , , , These are the reference values ​​for the corresponding characteristic parameters in all candidate configurations.

3. The screening method according to claim 2, characterized in that, The various characteristic gases include CO, NO, O3, and N2O4; The adsorption performance parameters include adsorption energy. Charge transfer amount Change rate of band gap before and after adsorption The rate of change of the total density of states of the material before and after adsorption at the Fermi level .

4. The screening method according to claim 3, characterized in that, The discrimination index is obtained by the following formula: in, This is the discrimination index for the current configuration, where n=4 represents the number of gas species. and The first i species and first j The adsorption performance vector corresponding to each gas, ∥ ∥ is the vector norm. The larger the value, the greater the degree of difference in the response of the corresponding configuration to the four gases.

5. The screening method according to claim 4, characterized in that, The parameter components in the adsorption performance vector are normalized using Min-Max before calculation. The normalization formula is as follows: in, For the first i gas, the first m The original values ​​of the adsorption parameters; and Each of the gases in the th m Minimum and maximum values ​​of the parameters; These are the normalized parameter components.

6. The screening method according to claim 5, characterized in that, The balance index is obtained by the following formula: in, This is the balance index for the current configuration; and Let be the theoretical response time and theoretical desorption time of the k-th gas, respectively, and we have: in, This is the initial adsorption distance. To balance the adsorption distance, The natural vibration frequency of the atom, The adsorption activation energy, Boltzmann's constant, T To preset the operating temperature, Let be Planck's constant. This is the desorption energy.

7. The screening method according to claim 6, characterized in that, The comprehensive score is obtained by the following formula: in, This is the overall score for the current configuration; , , These are the comprehensive thermodynamic stability index, the distinguishability index, and the equilibrium index for the current configuration, respectively. , , These are the weight coefficients for each item; , , These are the maximum value of the thermodynamic stability comprehensive index, the maximum value of the discrimination index, and the maximum value of the discrimination index among all configurations that meet the preset conditions. The maximum value.

8. The screening method according to claim 7, characterized in that, The optimal modification configuration is gallium nitride nanotubes modified with palladium trimer clusters, wherein the palladium trimers are vertically anchored to the active sites of the pores on the surface of the gallium nitride nanotubes in a spatial triangular configuration, and the adsorption energies of the four gases of this optimal modification configuration are ranked as N2O4>CO>O3>NO.

9. A screening device for detecting the optimal modified Pd-GaNNT configuration for switchgear fault characteristic gases using the method described in any one of claims 1-8, characterized in that, include: The module is used to construct multiple candidate modification configurations of palladium-modified gallium nitride nanotubes (Pd-GaNNTs), wherein the multiple candidate modification configurations include at least palladium single-atom doping configuration, palladium dimer cluster doping configuration, palladium trimer cluster doping configuration, and palladium tetramer cluster doping configuration; The stability index determination module is used to determine multiple characteristic parameters for each candidate modification configuration based on DFT, compare each characteristic parameter with the corresponding characteristic parameter reference value of the corresponding candidate modification configuration and weight and fuse them to obtain the comprehensive thermodynamic stability index of the corresponding candidate modification configuration, and screen out the configurations with a comprehensive thermodynamic stability index greater than a preset threshold. The discrimination index determination module is used to calculate the adsorption performance parameters of each selected configuration for multiple characteristic gases of switchgear faults, and calculate the discrimination index of the selectivity of multiple characteristic gases for each selected configuration based on the adsorption performance parameters. The discrimination index is used to measure the degree of difference in the response of the configuration to the multiple characteristic gases. The balance index determination module is used to determine the dynamic response-recovery balance index of each selected configuration at a preset operating temperature. The balance index is used to measure the degree of matching between the response rate of the configuration to the target gas and its desorption recovery capability. The selection module is used to determine a comprehensive score for each selected configuration based on the thermodynamic stability comprehensive index, the discrimination index, and the equilibrium index, and select the configuration whose comprehensive score meets the predetermined conditions as the optimal modified configuration.

10. A terminal, comprising a processor and a storage medium; characterized in that: The storage medium is used to store instructions; The processor is configured to operate according to the instructions to perform the steps of the method according to any one of claims 1-8.

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