High Voltage最新文献

{"title":"Predicting transformer temperature field based on physics-informed neural networks","authors":"Pengfei Tang,&nbsp;Zhonghao Zhang,&nbsp;Jie Tong,&nbsp;Tianhang Long,&nbsp;Can Huang,&nbsp;Zihao Qi","doi":"10.1049/hve2.12435","DOIUrl":"10.1049/hve2.12435","url":null,"abstract":"<p>The safe operation of oil-immersed transformers is critical to the safety and stability of the power grid. As the operating time increases, the failure rate of oil-immersed transformers shows an increasing trend, posing serious challenges to safe operation. It is necessary to investigate the internal state of the oil-immersed transformer to improve the digital degree and achieve digitalisation and intelligent operation and maintenance. A physics-informed neural network (PINN) for oil-immersed transformers was introduced to reconstruct the temperature distribution inside the transformer. According to the approach, the loss function of the network would be optimised by incorporating physical constraint loss terms including heat transfer equations, initial conditions and boundary conditions. The results show that the method proposed can be used to reconstruct and predict the temperature field of transformers in a few seconds with satisfactory accuracy. In conclusion, the PINN proposed outperforms deep neural networks in terms of accuracy, reliability and interpretability, especially in data-poor cases.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12435","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140996455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption and sensing characteristics of insulating gas C4F7N on 3d late transition metal-phthalocyanine: Theoretical and experimental study","authors":"Dachang Chen,&nbsp;Ziang Zheng,&nbsp;Cong Zhang,&nbsp;Yi Luo,&nbsp;Song Xiao,&nbsp;Qing Miao,&nbsp;Ke Liu,&nbsp;Beibei Xiao","doi":"10.1049/hve2.12437","DOIUrl":"10.1049/hve2.12437","url":null,"abstract":"<p>Heptafluoroisobutyronitrile (C₄F₇N) is being considered as a promising alternative to the greenhouse gas SF₆ in the electrical industry. However, its biotoxicity necessitates the development of gas sensing technology to detect leaked C₄F₇N. A combination of density functional theory and experiments was employed to evaluate the adsorption and sensing performance of different metal-phthalocyanines as potential sensing materials for C₄F₇N detection. The study included exploring adsorption configurations with adsorption energies, electron transfer, and adsorption distance, as well as comparisons of electronic properties, electron distribution, and density of states (DOS) among the MPcs. Furthermore, gas sensing experiments were conducted using different MPcs to detect 25–100 ppm C₄F₇N. The results revealed that Mn-Pc, Fe-Pc, Co-Pc, and Zn-Pc exhibited considerable chemical interactions, while Ni-Pc and Cu-Pc showed weaker adsorption strength. These findings were further elucidated based on the electron density and DOS of atomic orbitals. Moreover, gas sensing experiments indicated that Co-Pc demonstrated a higher response compared to Fe-Pc at the same concentration of C₄F₇N. Overall, the theoretical and experimental insights offer valuable guidance for C₄F₇N detection and provide a systematic approach to screen and explore organometallic polymer-based gas sensors applicable in various fields.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12437","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141004606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photodetector array for measuring the spatial–temporal distribution characteristics of electric field in oil–pressboard insulation based on the Kerr electro‐optic effect","authors":"Chunjia Gao, B. Qi, Chengrong Li, Yukung Zheng","doi":"10.1049/hve2.12442","DOIUrl":"https://doi.org/10.1049/hve2.12442","url":null,"abstract":"Accurate measurement and effective analysis of the space electric field and charge characteristics within the oil–pressboard insulation structure of converter transformer are essential for achieving precise insulation structure design. Presently, most electric field measurement methods relying on the Kerr electro‐optical effect are limited to single‐point measurements. Given the complexity of converter transformer insulation structures, including their large scale and the use of various materials, existing technologies and findings struggle to provide comprehensive electric field observations within the oil–pressboard region. After leveraging the Kerr electro‐optic effect, a high‐precision 32‐unit photodetector array has been developed to achieve regional measurements of spatial‐temporal electric field in oil–pressboard insulation. The array boasts a measurement spatial resolution of 1.4 mm2 and a sensitivity of 0.15 kV/mm, ensuring measurement accuracy exceeding 96.50%. Through practical measurements of the spatial electric field distribution within the oil–pressboard insulation under direct current voltage, the non‐uniform distribution of the electric field is effectively captured in oil. Notably, the maximum deviation in field strength at different positions within the transformer oil can reach 18.5%. Moreover, as the applied voltage increases, the unevenness coefficient of the field strength gradually rises, peaking at 1.19, which signifies a progressive expansion in the area affected by electric field distortion. By conducting tests to assess the dispersion of volume resistivity in samples from various positions within large sheets of pressboard, the variation in volume resistivity of materials is posited as one of the contributing factors to the non‐uniform distribution of electric field within the oil. The detailed accomplishments aim to provide essential technical and theoretical support for optimising insulation structure design of converter transformers.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140658093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental qualification and sensitivity study of antipodal patch antenna structures for orientation independent detection of partial discharges","authors":"Kerstin Friebe,&nbsp;Frank Jenau","doi":"10.1049/hve2.12434","DOIUrl":"10.1049/hve2.12434","url":null,"abstract":"<p>Partial discharge diagnosis is an important part of monitoring and diagnosing components of the power transmission system. Four different patch antenna structures for the detection of partial discharges are investigated. These patch antennas, which are realisable in a variety of geometric structures, are already the subject of research. They offer the advantage of contactless detection without intervention in the test object or the measuring circuit, and also offer the possibility of alignment independent detection compared to directional antennas. However, it is important and required to examine different structures extensively at the same measurement setup and to compare their performance. To achieve this, four different configurations of patch antenna structures based on basic geometries all in antipodal design are realised: a logarithmic periodic structure, a Hilbert fractal structure and two tapered slot antennas. They are exposed to the same conditions on a special and unique measurement setup. As the main aspect, the performance of orientation independent detection of partial discharges patch antennas with varying distance and rotation in relation to the partial discharge source as well as the operating bandwidth is examined. To rate the structures, an evaluation scheme is created and a sensitivity matrix is generated.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12434","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140690516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of electrothermal ageing on dielectric performance of metallised biaxial orientation polypropylene film capacitors in strong magnetic fields","authors":"Haoliang Liu,&nbsp;Boxue Du,&nbsp;Meng Xiao,&nbsp;Ke Chen,&nbsp;Yanwei Ma","doi":"10.1049/hve2.12439","DOIUrl":"10.1049/hve2.12439","url":null,"abstract":"<p>The dielectric performance of the pristine and the electrothermal-aged metallised polypropylene capacitors are investigated under different magnetic fields. The energy storage capacity decreases under the magnetic field. At 12 T, the capacitance value of the pristine capacitors decreases by 8.4%–17% and that of the aged capacitors declines by 15%–20%. The dielectric loss is reduced by 2.6%–6.3%, but the equivalent series resistance shows an 8.3%–23.1% growth. The leakage conductivity increases to 202%–354%, which leads to a weakened voltage holding capacity. In addition to the effects of the magnetic fields, the impacts of ageing have also been investigated. The effects of the magnetic field and ageing on the electrical parameters of the capacitors are discussed separately. The molecular chains of the dielectric are oxidised and decomposed during the ageing process, which reduces the insulating properties of the dielectric. The magnetic field inhibits polarisation by changing the polarisation behaviour through Lorentz force and excites the electrons to enhance charge transmission.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12439","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140690998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhancing dielectric properties and energy storage performance of polyvinylidene fluoride composite by surface-modified AgNbO3 nanoparticles","authors":"Zhuo Wang,&nbsp;Ting Zhao,&nbsp;Dan Wu,&nbsp;Ying Xue,&nbsp;Zhihui Yi,&nbsp;Jinteng Kang,&nbsp;Ronghui Ye,&nbsp;Ning Guo","doi":"10.1049/hve2.12438","DOIUrl":"10.1049/hve2.12438","url":null,"abstract":"<p>The introduction of antiferroelectric filler AgNbO₃ into the polyvinylidene fluoride (PVDF) polymer matrix enhances its energy storage properties of PVDF. However, AgNbO₃ and PVDF matrix are incompatible due to their distinct physical and chemical properties, resulting in poor compatibility between the two phases. Surface modification enhances the large difference in physical and chemical properties between the filler and the polymer matrix, and improves the compatibility between the two phases. Silane coupling agents (KH550, KH560), dopamine (DA), and grafted poly(methyl methacrylate) (PMMA) were used to modify the surface of AgNbO₃ particles, and the effects of different surface modification methods on the energy storage performance of the composites were studied. The PVDF matrix was introduced with 0.3 wt% AgNbO₃ particle filler. The results showed that the amino group in KH550 had the strongest binding with PVDF. The ester group in PMMA has a strong binding with PVDF. The epoxy group in KH560 has a weak binding with PVDF, while the amino group in DA has the worst binding with PVDF. The compatibility of the two phases in AgNbO₃@KH550/PVDF composites is the best, and the charge distribution on the surface of the filler is uniform. Under an electric field of 350 kV/mm, the energy storage density is 8.48 J/cm³.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12438","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140692066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Dielectric and thermal properties characterisation and evaluation of novel epoxy materials for high-voltage power module packaging","authors":"Zhengdong Wang,&nbsp;Ganqiu Yang,&nbsp;Xiaolong Cao,&nbsp;Mengli Li,&nbsp;Tong Zhang,&nbsp;Chenxin Liu,&nbsp;Yuanhang Zhou,&nbsp;Yonghong Cheng","doi":"10.1049/hve2.12443","DOIUrl":"10.1049/hve2.12443","url":null,"abstract":"<p>Internal insulation of high-voltage power modules is facing interesting failure risks, including high temperature overheating, breakdown fault, material cracking etc., so it is imperative to urgently develop new dielectric materials with high thermal conductivity (<i>λ</i>), outstanding electrical insulation, and thermal stability properties. A method to construct controllable liquid crystalline cross-linking networks based on the synthesis of biphenyl epoxy monomer and the change of curing agent structures and curing temperature is proposed. The uniform nematic rod-like liquid crystalline domains were obtained by using 4,4-diaminodiphenylmethane as a curing agent under a pre-curing temperature of 105°C. The resulting film (abbreviated as TD-105) exhibited <i>λ</i> up to 0.53 W m⁻¹ K⁻¹ and a dielectric breakdown strength of 57.69 kV mm⁻¹, which showed a simultaneous enhancement of 178% and 16%, respectively, compared to traditional bisphenol A epoxy resin. Moreover, it also exhibited lower dielectric loss and magnitude of partial discharge while having higher glass-transition temperature (190°C). A novel idea for the development of high-performance epoxy insulating materials for the application of high-voltage and large-power electrical equipment is provided.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12443","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140693882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on the evaluation method of polymerisation degree based on Raman spectroscopic plot","authors":"Zhuang Yang,&nbsp;Weigen Chen,&nbsp;Zhixian Yin,&nbsp;Dingkun Yang","doi":"10.1049/hve2.12432","DOIUrl":"10.1049/hve2.12432","url":null,"abstract":"<p>In order to achieve accurate quantitative evaluation of the ageing state of oil paper insulation, an evaluation method of polymerisation degree (DP) of oil–paper insulation based on Raman spectroscopic plot is presented. Samples covering the full ageing stage of oil–paper insulation were obtained by accelerated thermal ageing experiments. The samples were tested by Raman spectra, and the Raman spectra were converted into Raman spectroscopic plot using Gramian angular field. Feature extraction was performed on the images using local binary pattern (LBP), and 28 feature variables were selected by competitive adaptive reweighted sampling and uninformative variable elimination. Finally, the DP prediction model was constructed by long short-term memory neural network (LSTM). The training accuracy exceeded 90%, and the mean absolute deviation of DP prediction for 45 test samples was only 40.70. A new visual detection method for transformer ageing diagnosis is presented.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12432","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140694282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating transient behaviour of large-scale photovoltaic systems during lightning events using enhanced finite difference time domain method with variable cell size approach","authors":"Ibrahim Hetita,&nbsp;Diaa-Eldin A. Mansour,&nbsp;Yang Han,&nbsp;Ping Yang,&nbsp;Congling Wang,&nbsp;Mohamed M. F. Darwish,&nbsp;Matti Lehtonen,&nbsp;Amr S. Zalhaf","doi":"10.1049/hve2.12440","DOIUrl":"10.1049/hve2.12440","url":null,"abstract":"<p>Photovoltaic (PV) arrays are usually installed in open areas; hence, they are vulnerable to lightning strikes that can result in cell degradation, complete damage, service disruption, and increased maintenance costs. As a result, it is imperative to develop an effective and efficient lightning protection system by evaluating the transient behaviour of PV arrays during lightning events. The aim is to evaluate the transient analysis of large-scale PV systems when subjected to lightning strikes using the finite difference time domain (FDTD) technique. Transient overvoltages are calculated at various points within the mounting system. To optimise the FDTD method's execution time and make it more suitable for less powerful hardware, a variable cell size approach is employed. Specifically, larger cell dimensions are used in the earthing system and smaller cell dimensions are used in the mounting system. The FDTD method is utilised to calculate the temporal variation of transient overvoltages for large-scale PV systems under different scenarios, including variations in the striking point, soil resistivity, and the presence of a metal frame. Simulation results indicate that the highest transient overvoltages occur at the striking point, and these values increase with the presence of a PV metal frame as well as with higher soil resistivity. Furthermore, a comparison is performed between the overvoltage results obtained from the FDTD approach and the partial element equivalent circuit (PEEC) method at the four corner points of the mounting systems to demonstrate the superior accuracy of the FDTD method. Besides, a laboratory experiment is conducted on a small-scale PV system to validate the simulation results. The calculated overvoltages obtained from the FDTD and PEEC methods are compared with the measured values, yielding a mean absolute error of 5% and 11% for the FDTD and PEEC methods, respectively, thereby confirming the accuracy of the FDTD simulation model.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12440","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140690710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study on detecting main ingredients of silicone rubber based on terahertz spectrum","authors":"Hongwei Mei,&nbsp;Lanxin Li,&nbsp;Fanghui Yin,&nbsp;Liming Wang,&nbsp;Masoud Farzaneh","doi":"10.1049/hve2.12427","DOIUrl":"10.1049/hve2.12427","url":null,"abstract":"<p>The authors investigated the ingredient detection technique of silicone rubber based on the Terahertz spectrum. For this purpose, 18 diverse high-temperature vulcanised silicone rubber (HTVSR) formulations were customised, 8 of which are used as calibration set while the rest 10 as prediction set. Based on the Beer-Lambert Law, the partial-least-square (PLS) regression model and the least-squares support-vector machines (LS-SVM) regression model were used to yield the relationships between the absorption spectrums and the content percentages of polydimethylsiloxane (PDMS), alumina trihydrate (ATH), and silica in HTVSR. The results showed that for the formulations tested, the prediction accuracy of all three main ingredients by the PLS regression model could be improved by changing the spectrum range from 0.2–4 to 0.5–2 THz. If the data were pre-processed by the Savitzky–Golay smoothing method or multiplicative scatter correction method, the prediction accuracy of PDMS could be further enhanced. However, this would lead to a slight decrease in the prediction accuracy of ATH. For the LS-SVM regression model, the radial basis function (RBF) kernel and the linear kernel were studied. It was found that the prediction accuracy of both kernels was better than that of the PLS regression model. With the LS-SVM regression model using the RBF kernel, the correlated coefficients of PDMS and ATH in the prediction set could be up to 0.9915 and 0.9742, respectively.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12427","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140303473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}