High Voltage最新文献_第2页

Study on the terahertz domain dielectric relaxation response and mechanism of thermal‐oxidative aged cross‐linked polyethylene 热氧化老化交联聚乙烯的太赫兹域介电弛豫响应及机理研究

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-07-11 DOI: 10.1049/hve2.12463

Mengqi Wang, Shihang Wang, Xinyu Li, Yang Feng, Jingran Wang, Shengtao Li

{"title":"Study on the terahertz domain dielectric relaxation response and mechanism of thermal‐oxidative aged cross‐linked polyethylene","authors":"Mengqi Wang, Shihang Wang, Xinyu Li, Yang Feng, Jingran Wang, Shengtao Li","doi":"10.1049/hve2.12463","DOIUrl":"https://doi.org/10.1049/hve2.12463","url":null,"abstract":"To further study the thermal‐oxidative ageing mechanism of crosslinked polyethylene (XLPE), the terahertz frequency domain dielectric parameters and relaxation phenomena of thermal‐oxidative aged XLPE are analysed using terahertz time domain spectroscopy. It is found that the real part of the terahertz dielectric constant increases with the increase of thermal‐oxidative ageing duration, and the imaginary part shows an overall upward trend. Relaxation of the complex dielectric constant of the aged XLPE samples is obvious. Through the second‐order Cole–Cole equation fitting, it is found that there are two relaxation processes around 0.15 and 1.5 THz, and the relaxation strength gradually increases with the ageing time. To explain this phenomena, microstructure changes and crystallisation behaviours are characterised using Fourier transform infrared spectrum and differential scanning calorimetry, respectively. It is suggested that the two relaxations may be caused by elastic dipole polarisation originating from the angular deflection of polar groups and stretching rotation of hydrogen bond. In addition, by comparing the relaxation strength in different temperatures, the source of the relaxation process is further confirmed.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141656601","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}

引用次数: 0

Safety monitoring method for powerline corridors based on single-stage detector and visual matching 基于单级探测器和视觉匹配的电力线走廊安全监测方法

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-07-11 DOI: 10.1049/hve2.12464

Jinheng Li, Hanbo Zheng, Peng Liu, Yanshen Liang, Feng Shuang, Junjie Huang

{"title":"Safety monitoring method for powerline corridors based on single-stage detector and visual matching","authors":"Jinheng Li, Hanbo Zheng, Peng Liu, Yanshen Liang, Feng Shuang, Junjie Huang","doi":"10.1049/hve2.12464","DOIUrl":"10.1049/hve2.12464","url":null,"abstract":"Effective monitoring and early warning of overhead power lines are critical for ensuring power supply stability and personnel safety. However, existing methods that rely solely on single vision or light detection and ranging (LiDAR) have limitations such as numerous invalid alarms, hardware equipment constraints, and lack of real-time monitoring capabilities. This article proposes an intelligent monitoring method for safety distance of the powerline corridor based on heterogeneous sensor information. Firstly, an optimised single-stage detector is designed to detect safety hazard objects. In the detector, the backbone network and the sample matching strategy are improved; in addition, the learning strategy is adjusted. Next, the pose transformation relationship is obtained through the visual matching of prior LiDAR information and images. The back projection transformation of 2D–3D is achieved according to the relationship. Finally, a monocular camera-based end-to-end distance measurement scheme is proposed by combining 2D object information with coordinate transformation relationships. The scheme is applied to the distance measurements from hazard objects to powerlines. The experimental results show that the optimisation method improves the detection accuracy and reduces the computational complexity of the model. Also, case experiments with continuous frame data verify the effectiveness of the safety distance monitoring scheme.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12464","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141657744","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}

引用次数: 0

Mesh‐free Monte Carlo method for electrostatic problems with floating potentials 浮动势静电问题的无网格蒙特卡洛方法

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-07-07 DOI: 10.1049/hve2.12468

Wenjing Yin, Yunqing Wang, Hong Deng, Jiawei Wang, Xiaoke Gao, Ruoyu Huang, Kun He, Weijiang Chen, T. Dong

{"title":"Mesh‐free Monte Carlo method for electrostatic problems with floating potentials","authors":"Wenjing Yin, Yunqing Wang, Hong Deng, Jiawei Wang, Xiaoke Gao, Ruoyu Huang, Kun He, Weijiang Chen, T. Dong","doi":"10.1049/hve2.12468","DOIUrl":"https://doi.org/10.1049/hve2.12468","url":null,"abstract":"Numerical simulation plays a crucial role in the analysis and design of power equipment, such as lightning protection devices, which may become inefficient using traditional grid‐based methods when handling complex geometries of large problems. The authors propose a grid‐free Monte Carlo method to handle electrostatic problems of complex geometry for both the interior and exterior domains, which is governed by the Poisson equation with a floating potential boundary condition that is neither a pure Dirichlet nor a Neumann condition. The potential and gradient at any given point can be expressed in terms of integral equations, which can be estimated recursively within the walk‐on‐sphere algorithm. Numerical examples have been demonstrated, including the evaluation of the mutual capacitance matrix of multi‐conductor structures and lighting striking near real fractal trees. The proposed method shows advantages in terms of geometric flexibility and robustness, output sensitivity, and parallelism, which may become a candidate for game‐changing numerical methods and exhibit great potential applications in high‐voltage engineering.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141671274","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}

引用次数: 0

Analysis of electrical–thermal‐stress characteristics for eccentric contact strip in the valve‐side bushing of converter transformer 变流器变压器阀侧套管中偏心接触带的电气-热应力特性分析

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-07-04 DOI: 10.1049/hve2.12467

Yongqi Wang, Kai Liu, M. Lin, H. Tang, Xining Li, Guangning Wu

{"title":"Analysis of electrical–thermal‐stress characteristics for eccentric contact strip in the valve‐side bushing of converter transformer","authors":"Yongqi Wang, Kai Liu, M. Lin, H. Tang, Xining Li, Guangning Wu","doi":"10.1049/hve2.12467","DOIUrl":"https://doi.org/10.1049/hve2.12467","url":null,"abstract":"Ultra‐high voltage direct current (UHVDC) transmission project in China is expanding, and the technology is increasingly maturing. The converter transformer is a crucial component in the UHVDC transmission projects, and its valve‐side bushing plays a key role in ensuring the stable operation of the power system. This paper investigates the electrical–thermal‐stress distribution characteristics of the contact strip in an eccentric state. The research focuses on a section of the contact strip in the plug oil at the tail end of the bushing on the valve side of the converter. A three‐dimensional finite element simulation model is established, and the contact strip contact resistance is used to define the contact strip eccentricity. The temperature rise platform of the contact strip was constructed to verify the precision of the simulation outcomes. The study investigated the variations in electric, thermal, and stress of contact strips in various eccentric states, as well as transient development, and the four stages of contact strip deformation were summarised using calculation results, providing quantitative analysis criteria for assessing the degree of deterioration of contact strips under eccentric conditions. Through the test and calculation, it can be seen that the contact resistance of the normal contact strip changes with the height in the form of a typical first‐order exponential function. The contact resistance value is between 200 and 400 μΩ under the actual mounting height; for the brand‐new contact strip, the maximum temperature difference is 2.984 K without other interference; and after 15 min, the maximum displacements of the upper and lower half‐ring strips reached are 84.3 and 83.7 μm, respectively, due to the thermal expansion. The study results offer a theoretical foundation for understanding the failure of elastic electrical connection components in the bushing on the valve side of the converter.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141679254","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}

引用次数: 0

Influence of different anodised nanoporous structures on the anti‐icing and electrical properties of transmission Al lines 不同阳极氧化纳米多孔结构对输电铝线防冰和电气性能的影响

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-07-04 DOI: 10.1049/hve2.12471

Xueying Dai, Yuan Yuan, Jie Xiao, Chenghao Jiang, Xujiang Hua, Huiying Xiang, Tao Zhu, Guoyong Liu, Jiang Zhou, Ruijin Liao

{"title":"Influence of different anodised nanoporous structures on the anti‐icing and electrical properties of transmission Al lines","authors":"Xueying Dai, Yuan Yuan, Jie Xiao, Chenghao Jiang, Xujiang Hua, Huiying Xiang, Tao Zhu, Guoyong Liu, Jiang Zhou, Ruijin Liao","doi":"10.1049/hve2.12471","DOIUrl":"https://doi.org/10.1049/hve2.12471","url":null,"abstract":"Ice accumulation of overhead transmission lines can lead to serious damage to power systems. Superhydrophobic nanostructured Al conductors are proposed to replace the de‐icing or ice‐melting equipment for economic advantages, good anti‐icing properties and robust electrical performance. Anodisation under different direct current densities is adopted to fabricate two nanostructures on Al conductors, including the reticular and honeycomb‐like nanoporous structures. Compared to pure Al conductors, the anodised surface of honeycomb‐like nanoporous structures exhibits lower ice adhesion (3.82 kPa) and ice accumulation. Aluminium conductor steel reinforced treated in the proposed method has also been validated to exhibit a significant anti‐glaze icing property. Additionally, corona performance and line loss are experimentally measured and calculated to prove good electrical performance. The 0.27 A Al strand shows the highest corona inception voltage (27.86 kV) and the lowest AC resistance (4.65 Ω/km), which is attributed to the good dielectric property and heat dissipation. Therefore, the proposed anti‐icing transmission conductors show profound application potential for power systems.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141678087","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}

引用次数: 0

The relationship between power of arc discharge in transformer oil and peak value of the shock wave 变压器油中电弧放电功率与冲击波峰值之间的关系

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-07-03 DOI: 10.1049/hve2.12462

Guangjin Zhang, Tianyu Han, Tao Wen, Yi Zhao, Weijiang Chen, Qiaogen Zhang, Jinzhong Li, Ke Wang

{"title":"The relationship between power of arc discharge in transformer oil and peak value of the shock wave","authors":"Guangjin Zhang, Tianyu Han, Tao Wen, Yi Zhao, Weijiang Chen, Qiaogen Zhang, Jinzhong Li, Ke Wang","doi":"10.1049/hve2.12462","DOIUrl":"https://doi.org/10.1049/hve2.12462","url":null,"abstract":"Since 2018, there have been seven incidents of explosions and fires in ultra‐high voltage transformers in China, which are caused by internal arc discharge in transformer oil. Various pressure measurement experiments have been conducted to explore the laws of discharge pressure. However, differences in experimental conditions, discharge energy, and current peak values have led to discrepancies in the discharge power and pressure laws in these experiments. Thus, it is crucial to investigate the relationship between arc discharge power and pressure peak in transformer oil. An arc discharge test platform was established to measure pressure waveforms based on the RLC circuit. Additionally, a shadow optical path observation system was implemented to record the development process of discharge arc, bubble pulsation, and shock waves. The study reveals the positive relationship between the average power and the peak value of the shock wave; the former refers to the breakdown and expansion stage of the arc channel, and the latter is generated by the discharge, respectively. Overall, the pressure generation mechanism of arc discharge in transformer oil and the relationship between arc discharge power and peak value of discharge pressure are revealed.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141680869","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}

引用次数: 0

10 kV nanosecond pulse generator with high voltage gain and reduced switches 10 kV 纳秒脉冲发生器，具有高电压增益和更小的开关

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-07-03 DOI: 10.1049/hve2.12470

Jiuxin Ma, Liang Yu, Chenguo Yao, Shoulong Dong, Chengxiang Li, Lvheng Ren, Shixin Wang

引用次数: 0

SO2 and SOF2 simultaneous detection by single mid-infrared laser based on tunable diode laser absorption spectroscopy 基于可调谐二极管激光吸收光谱的单个中红外激光器同时检测 SO2 和 SOF2

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-06-21 DOI: 10.1049/hve2.12451

Yin Zhang, Yan Li, Jin Yan, Chao Bian, Xuan Chen, Xiaoxing Zhang

{"title":"SO2 and SOF2 simultaneous detection by single mid-infrared laser based on tunable diode laser absorption spectroscopy","authors":"Yin Zhang, Yan Li, Jin Yan, Chao Bian, Xuan Chen, Xiaoxing Zhang","doi":"10.1049/hve2.12451","DOIUrl":"https://doi.org/10.1049/hve2.12451","url":null,"abstract":"In the detection of multi-component gas based on tunable diode laser absorption spectroscopy (TDLAS), the problem of overlapping interference between the absorption lines of each gas is often encountered. For example, when detecting a gas mixture of sulphur dioxide (SO2) and thionyl fluoride (SOF2), the characteristic decomposition components of SF6, there is overlapping interference in the absorption lines of the two gases, which makes it difficult to detect the concentration of gases accurately. In view of this problem, a novel method based on support vector regression model used for TDLAS is proposed to detect two gases simultaneously. The detection results show that the correlation coefficients between the concentration of SO2 and SOF2 and the average value of the second harmonic peak reached 0.992 and 0.993. In addition, through model testing, different concentrations of SO2 and SOF2 gas mixture are simultaneously detected, and the resulting maximum errors for measuring SO2 and SOF2 concentrations are less than 7.13 × 10−5 and 0.26 × 10−2. The maximum errors of the measurement results in the verification test are not more than 6.4 × 10−3 and 4.6 × 10−2. Therefore, with assistance of the novel method, the detection of multiple gases by using a single laser is achieved.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12451","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142007245","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}

引用次数: 0

Influence of imidazolium ionic liquids as organic filler dispersant on electrical properties of chitin/epoxy composites 咪唑离子液体作为有机填料分散剂对甲壳素/环氧树脂复合材料电气性能的影响

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-06-19 DOI: 10.1049/hve2.12461

Kai Yin, Qihong Fan, Jing Li, Taqi ur Rahman, Tianyin Zhang, Ashish Paramane, Xiangrong Chen

{"title":"Influence of imidazolium ionic liquids as organic filler dispersant on electrical properties of chitin/epoxy composites","authors":"Kai Yin, Qihong Fan, Jing Li, Taqi ur Rahman, Tianyin Zhang, Ashish Paramane, Xiangrong Chen","doi":"10.1049/hve2.12461","DOIUrl":"https://doi.org/10.1049/hve2.12461","url":null,"abstract":"Ionic liquid (IL) as the dispersant can help disperse the organic nanofillers to improve the performance of epoxy resin remarkably. However, the effect of IL on the electrical properties of epoxy composites is not well documented. This comprehensive study consists of the preparation, material characterisation and systematical investigation of electrical properties of 1-Butyl-3-methylimidazole hexafluorophosphate-modified chitin fibre/epoxy composites. The findings show that introducing IL into a chitin/epoxy composite can minimise porosity defects and improve the compatibility between filler and matrix. However, a high concentration of IL induces severe charge injection into chitin/epoxy composites and internal electric field distortion. The addition of 0.75%–1.5% mass fraction IL results in maximum enhancement in the AC breakdown strength of the chitin/epoxy composite (by ∼71%) compared with the non-IL composites. The non-linear conductivity and non-uniform charge injection phenomena of IL-modified composites can be attributed to the movement of radicals and anions due to the decomposition of IL. Through this study, it is highly expected that the organic filler dispersion in the epoxy matrix can be optimised by tuning IL to improve the insulation properties.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12461","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142007249","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}

引用次数: 0

Design of a high-frequency transformer based on amorphous cut cores for insulation breakdown testing 设计基于非晶切割磁芯的高频变压器，用于绝缘击穿测试

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-06-19 DOI: 10.1049/hve2.12460

Gijs Lagerweij, Mohamad Ghaffarian Niasar

{"title":"Design of a high-frequency transformer based on amorphous cut cores for insulation breakdown testing","authors":"Gijs Lagerweij, Mohamad Ghaffarian Niasar","doi":"10.1049/hve2.12460","DOIUrl":"https://doi.org/10.1049/hve2.12460","url":null,"abstract":"Innovative test methods are required to keep up with the increased demand for insulation materials which can withstand the high-frequency square-wave voltages generated by power-electronic equipment. Test systems using high-voltage, high-frequency transformers have proven versatile and easy to realise. The authors investigate the application of amorphous cut cores in such transformers. Analytical and numerical models for the transformer and its frequency response are developed, aiding the design process. An amorphous core-based transformer is designed for 8 kVpk output at 100 kHz and compared to two previous designs based on ferrite cores. The frequency and pulse response, as well as the high-voltage and thermal performance, are evaluated. The comparison shows that while the low parasitics of the amorphous-based transformer allow for superior frequency response, they are unsuitable for long-duration tests with high pulse repetition frequencies (25–100 kHz) due to increased core losses. The partial discharge inception and flashover voltage are comparable to the ferrite-based transformers.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":null,"pages":null},"PeriodicalIF":4.4,"publicationDate":"2024-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12460","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142540842","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}

引用次数: 0