High Voltage最新文献

{"title":"Detection of characteristic component H2S in SF6 and SF6/N2 mixture using cavity ring-down spectroscopy","authors":"Anhao Jiang,&nbsp;Chaohai Zhang,&nbsp;Min Zhu,&nbsp;Xiaoxing Zhang","doi":"10.1049/hve2.12508","DOIUrl":"https://doi.org/10.1049/hve2.12508","url":null,"abstract":"<p>A high-sensitivity cavity ring-down spectroscopy gas detection system with integrated optical components and embedded microprocessor units is presented for the detection of hydrogen sulfide (H₂S) in sulphur hexafluoride (SF₆) and its mixture with nitrogen (N₂). The system exploits a periodic laser wavelength modulation to simplify the mode matching. Spectral line profile fitting is used for sample quantitative analysis. To verify the sensitivity and stability of concentration detection, the effect of background gas and temperature on the responses of spectral line broadening and absorption cross-section are investigated. The result deviation caused by variation of background gas can be compensated by the pre-correction of empty cavity ring-down time. It is also found that the implication of temperature on the spectra cannot be ignored. The full width at half maximum and peak value decreased linearly with the increase of temperature, while the baseline is undergoing accelerated growth. Using Allan variance analysis, the limits of detection reach 4.44 × 10⁻⁹ in SF₆ and 2.96 × 10⁻⁹ in N₂ with average time of 67 s. This study provides a meaningful approach for the online detection of characteristic gas in gas insulation equipment.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 1","pages":"88-94"},"PeriodicalIF":4.4,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12508","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143535931","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":"Discharge image reconstruction and frequency domain analysis based on event data","authors":"Quan Yuan,&nbsp;Lei Deng,&nbsp;Hao Guo,&nbsp;Qishen Lyu,&nbsp;Xin Zhang,&nbsp;Jibin Wu,&nbsp;Yu Deng,&nbsp;Hongyang Zhou,&nbsp;Xilin Wang,&nbsp;Zhidong Jia","doi":"10.1049/hve2.12498","DOIUrl":"https://doi.org/10.1049/hve2.12498","url":null,"abstract":"<p>Optical image method has been the earliest and most used direct method for observing gas discharge. Currently, research on gas discharge monitoring based on visible light mainly relies on high-speed cameras, but the large size, significant data storage requirements, and susceptibility to interference from complex backgrounds and lighting conditions limit their further application. Dynamic vision sensing (DVS) technology is a neuromorphic sensing technology that asynchronously measures the luminance changes at each pixel. It offers advantages such as a large dynamic range (&gt;120 dB), high temporal resolution (up to 1 µs), and small data volume (MB level). In this study, dynamic vision sensing technology was employed to monitor both 30 mm short-gaps and 1080 mm long-gaps discharge processes simultaneously. This study developed the CountImage encoding method for event data and conducted image reconstruction, time-domain analysis, and frequency-domain characteristic analysis based on the event data. The results show that the event-reconstructed images are highly consistent with the high-speed camera images, and the arc development process and its path can also be clearly observed. Additionally, this study discovered a correlation between the electrical characteristics and event information during the discharge process. In the time domain, the duration of the maximum DVS event count closely matches the duration during which the voltage drops to zero during flashover. In the frequency domain, the Pearson correlation coefficient between the event stream spectrum and the voltage signal spectrum is greater than 0.95. Both the maximum number of brightening events (<i>ON</i>_max) and the maximum number of darkening events (<i>OFF</i>_max) are positively correlated with the voltage applied between the electrodes. This study demonstrates that, compared to the GB/s data rate of high-speed cameras, this approach can record the discharge process and accurately reconstruct the discharge process, arc morphology, and discharge path at MB/s data rates, while also adapting to changes in brightness without the need for exposure adjustment. Additionally, there is a positive correlation between the frequency-domain characteristics of the event data and the voltage characteristics. These results indicate that dynamic vision sensing holds promise as a replacement for high-speed cameras in laboratory discharge observations and could be even effectively applied to discharge monitoring in electrical equipment in real grid.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 6","pages":"1195-1201"},"PeriodicalIF":4.4,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12498","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143252728","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":"Space charge characteristics and dielectric properties of PANI/PP-g-MAH/PP ternary composite","authors":"Guochang Li,&nbsp;Tianzhen Liu,&nbsp;Zhenlu Gu,&nbsp;Xiaolong Chen,&nbsp;Beibei Sun,&nbsp;Yuanwei Zhu,&nbsp;Shengtao Li,&nbsp;Yanhui Wei","doi":"10.1049/hve2.12497","DOIUrl":"https://doi.org/10.1049/hve2.12497","url":null,"abstract":"<p>Space charge accumulation in polypropylene materials for direct current capacitor will accelerate the ageing of the materials, resulting in the degradation of their insulation properties. Besides, it will also affect the dielectric properties of the capacitor in a long term. In this paper, a ternary composite of polyaniline (PANI)/maleic anhydride functionalised PP (PP-g-MAH)/polypropylene (PP) based on the PANI@ dopamine (PDA) coating structure is constructed from two perspectives of PP matrix grafting and PANI nano particle. This method takes advantage of the high permittivity and good compatibility of PANI to improve the relative dielectric constant of the composite while introducing deep traps inside the composite to inhibit space charge accumulation coating. The experimental results show that with the increase in PANI content, the maximum relative permittivity can be increased by 62%. The addition of the appropriate amount of PANI can effectively inhibit the space charge accumulation. The relative dielectric constant of the composite decreases significantly due to the heteropolar space charge. The relative dielectric constant of the modified polyaniline composites decreased significantly. The reduction rate decreased from 38% before modification to 12% after modification. This work has certain guiding significance for solving space charge problem of direct current capacitor.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 1","pages":"178-185"},"PeriodicalIF":4.4,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12497","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536054","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":"Differences in M-components between triggered lightning striking the ground and overhead line","authors":"Li Cai,&nbsp;Yiyang Du,&nbsp;Wenchao Fan,&nbsp;Mi Zhou,&nbsp;Jianguo Wang,&nbsp;Jinxin Cao,&nbsp;Yadong Fan","doi":"10.1049/hve2.12493","DOIUrl":"https://doi.org/10.1049/hve2.12493","url":null,"abstract":"<p>In the summer of 2018–2019, rocket-triggered lightning experiments were conducted in Guangzhou, China. There were two types of lightning targets: ground and overhead line. By comparing the current and the electric field data in the two cases, it was found that when the continuous current level (<i>I</i>_CC) and current amplitude (<i>I</i>_M) of M-components (current pulses generated during the continuous current stage) are large, the time difference between the electric field peak and the current peak (<i>T</i>_D) will always be small. The rise time (<i>R</i>_T) and half peak width (<i>T</i>_HPW) of M-components with high <i>I</i>_CC and <i>I</i>_M are low in both the cases. The threshold upper limit of <i>T</i>_D in the case of lightning striking the ground is higher, approximately 2.6 times than that in the case of lightning striking the overhead line. We use an optimised guided wave model to simulate the electric field waveforms of M-components. It was found that the shorter <i>R</i>_T and <i>T</i>_HPW of the M-component, the smaller <i>T</i>_D. The changes in wave speed and <i>I</i>_M cannot affect the size of <i>T</i>_D, and the impact of distance changes is very weak. The difference in the threshold upper limit of <i>T</i>_D may be related to the significant difference in ground impedance in two cases.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 6","pages":"1260-1269"},"PeriodicalIF":4.4,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12493","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143252729","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":"Properties of diffuse and volume discharges that are important for their applications","authors":"Victor Tarasenko,&nbsp;Alexei Panchenko,&nbsp;Dmitry Beloplotov,&nbsp;Mikhail Lomaev,&nbsp;Dmitry Sorokin,&nbsp;Cheng Zhang","doi":"10.1049/hve2.12507","DOIUrl":"https://doi.org/10.1049/hve2.12507","url":null,"abstract":"<p>Diffuse and volume discharges are currently used widely in various fields. This work compares the properties of diffuse and volume discharges, as well as considers the conditions for their formation at high pressures. The main attention is paid to a diffuse discharge (DD). It has been shown that the ignition of a diffuse discharges is preceded by the development of a wide streamers. In the case of a volume discharge, the streamers usually have a small diameter and an ionisation waves emerging from it passes into the spark leader with subsequent discharge constriction. There are images and emission spectra of diffuse discharges in air and nitrogen in the paper. It has been confirmed that a diffuse discharges initiated by a nanosecond voltage pulse in a point-to-plane gaps has a uniform effect on the surface of a flat electrode. It was found that thin tracks of luminous particles are observed against the background of the DD plasma glow. They are associated with sputtering of the pointed electrode material due to the large field enhancement on the macro- and microinhomogeneities.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 1","pages":"126-136"},"PeriodicalIF":4.4,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12507","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143534002","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":"A novel embedded voltage-clamped circuit for multilevel modular converters submodule to suppress very fast transient overvoltage","authors":"Hong Shen,&nbsp;Zhonghao Dongye,&nbsp;Mian Xiao,&nbsp;Jiayi Shao,&nbsp;Xiangyu Zhang,&nbsp;Yao Yao,&nbsp;Zifan Dong,&nbsp;Lei Qi","doi":"10.1049/hve2.12510","DOIUrl":"https://doi.org/10.1049/hve2.12510","url":null,"abstract":"<p>The submodule in multilevel modular converters experiences a very fast transient overvoltage (VFTO) during switch operation of gas-insulated switchgear, which also results in overvoltage on power devices, such as thyristors and insulated gate bipolar transistors (IGBTs). This work presents an embedded circuit that utilises a gap in conjunction with a metal oxide varistor (MOV) to control the voltage of the surge arrester and prevent false triggers during the transient phase when the IGBT is turned off. The mechanism of VFTO is analysed. Moreover, the design idea is suggested and the gap-MOV circuit is constructed. Ultimately, experiments are conducted to validate the effectiveness of the suggested gap-MOV in suppressing overvoltage.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 6","pages":"1202-1207"},"PeriodicalIF":4.4,"publicationDate":"2024-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12510","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143252531","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":"Partial discharge characteristics of syntactic foam filled with hollow polymer microspheres","authors":"Le Li,&nbsp;Shuo Tan,&nbsp;Yunpeng Liu,&nbsp;Haoyi Li,&nbsp;Kezhi Xu,&nbsp;Guancheng Zhen,&nbsp;Xiaoxuan Yin,&nbsp;Tianfang Zhao,&nbsp;Wenhua Wu,&nbsp;Lei Yang","doi":"10.1049/hve2.12505","DOIUrl":"https://doi.org/10.1049/hve2.12505","url":null,"abstract":"<p>Syntactic foam materials, due to their advantages of low densities, low water absorption, and high dielectric strengths, have significant application potential in the cores of post insulators. However, because of a large number of microbubble structures within the syntactic foam, it might decrease the partial discharge inception voltage. It is necessary to investigate the partial discharge characteristics of the foam to assess the feasibility of its internal insulation application. In this study, the syntactic foam samples with four different microsphere contents (0%–2%) were prepared, and the physical structures of the materials were characterised by using Fourier transform infrared spectroscopy, scanning electron microscopy, and three-dimensional computed tomography. Subsequently, finite element simulations of the electric field were performed to analyse the influence of the microsphere content and distribution on the internal electric field of the syntactic foam. The results suggested that both the microsphere content and distribution affected the partial discharge activity. When the microsphere content was low, the doping of microspheres essentially meant that more air gap defects were present, leading to a decrease in the partial discharge performance. However, when the microsphere content was high, the microspheres were distributed in a dense and orderly manner, improving the field concentration phenomenon and hence inhibiting the partial discharge to a certain extent. In conclusion, the findings of this study provide a data reference and theoretical support for the application of syntactic foam in the cores of composite post insulators.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 6","pages":"1322-1335"},"PeriodicalIF":4.4,"publicationDate":"2024-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12505","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143248954","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":"Surface flashover in 50 years: II. Material modification, structure optimisation, and characteristics enhancement","authors":"Zhen Li,&nbsp;Ji Liu,&nbsp;Yoshimichi Ohki,&nbsp;George Chen,&nbsp;Shengtao Li","doi":"10.1049/hve2.12489","DOIUrl":"https://doi.org/10.1049/hve2.12489","url":null,"abstract":"<p>Surface flashover is a gas–solid interface insulation failure that significantly jeopardises the secure operation of advanced electronic, electrical, and spacecraft applications. Despite the widespread application of numerous material modification and structure optimisation technologies aimed at enhancing surface flashover performance, the influence mechanisms of the present technologies have yet to be systematically discussed and summarised. This review aims to introduce various material modification technologies while demonstrating their influence mechanisms on flashover performances by establishing relationships among ‘microscopic structure-mesoscopic charge transport-macroscopic insulation failure’. Moreover, it elucidates the effects of chemical structure on surface trap parameters and surface charge transport concerning flashover performance. The review categorises and presents structure optimisation technologies that govern electric field distribution. All identified technologies highlight that achieving a uniform tangential electric field and reducing the normal electric field can effectively enhance flashover performance. Finally, this review proposes recommendations encompassing mathematical, chemical, evaluation, and manufacturing technologies. This systematic summary of current technologies, their influence mechanisms, and associated advantages and disadvantages in improving surface insulation performance is anticipated to be a pivotal component in flashover and future dielectric theory.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 2","pages":"243-278"},"PeriodicalIF":4.4,"publicationDate":"2024-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12489","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892786","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":"Moisture dynamics during high-load fluctuations in transformers: Localised accumulation and interfacial transfer within oil/pressboard insulation","authors":"Shaoqi Wang,&nbsp;Qiaogen Zhang,&nbsp;Chong Guo,&nbsp;Yuhan Sun,&nbsp;Zhicheng Wu","doi":"10.1049/hve2.12486","DOIUrl":"https://doi.org/10.1049/hve2.12486","url":null,"abstract":"<p>Power systems grapple with the challenges of high load rates and intermittent new energy sources integration. Transformers, as vital equipment, employ oil/pressboard (oil/PB) insulation. Uneven moisture distribution in this insulation can jeopardise safety thresholds, necessitating precise moisture assessment for grid stability. A novel mathematical model, adsorption–desorption and porous media moisture transfer (ADP-MoT), is presented. This model incorporates adsorption and desorption processes within the porous pressboard, enabling a description of the dynamic moisture transfer between the oil and pressboard. Using this mathematical model, simulations for moisture dynamics were performed on a 750-kV transformer across four typical days. The results indicate that temperature fluctuations are the primary driving factor for moisture migration at the oil/PB interface. Convection and diffusion contribute to moisture movement towards cooler regions. Fluid properties and structural characteristics induce a distinctive streamline-shaped moisture flow within horizontal oil channels, with localised moisture accumulation in specific areas. Moreover, the analysis of 96 transient results uncovers potential free-state moisture formation during severe conditions, underscoring the importance of monitoring the pressboard at winding bases during high load fluctuations. In conclusion, this study significantly contributes to scientifically identifying and addressing risks tied to new energy sources integration in power systems.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 6","pages":"1221-1233"},"PeriodicalIF":4.4,"publicationDate":"2024-10-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12486","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143253150","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":"Research on temperature distribution characteristics of oil-immersed power transformers based on fluid network decoupling","authors":"Yongming Xu,&nbsp;Ziyi Xu,&nbsp;Congrui Ren,&nbsp;Yaodong Wang","doi":"10.1049/hve2.12488","DOIUrl":"https://doi.org/10.1049/hve2.12488","url":null,"abstract":"<p>Due to the complex structure and large size of large-capacity oil-immersed power transformers, it is difficult to predict the winding temperature distribution directly by numerical analysis. A 180 MVA, 220 kV oil-immersed self-cooling power transformer is used as the research object. The authors decouple the internal fluid domain of the power transformer into four regions: high voltage windings, medium voltage windings, low voltage windings, and radiators through fluid networks and establish the 3D fluid-temperature field numerical analysis model of the four regions, respectively. The results of the fluid network model are used as the inlet boundary conditions for the 3D fluid-temperature numerical analysis model. In turn, the fluid resistance of the fluid network model is corrected according to the results of the 3D fluid-temperature field numerical analysis model. The prediction of the temperature distribution of windings is realised by the coupling calculation between the fluid network model and the 3D fluid-temperature field numerical analysis model. Based on this, the effect of the loading method of the heat source is also investigated using the proposed method. The hotspot temperatures of the high-voltage, medium-voltage, and low-voltage windings are 89.43, 86.33, and 80.96°C, respectively. Finally, an experimental platform is built to verify the results. The maximum relative error between calculated and measured values is 4.42%, which meets the engineering accuracy requirement.</p>","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 5","pages":"1136-1148"},"PeriodicalIF":4.4,"publicationDate":"2024-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12488","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142540879","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}