High Voltage最新文献_第4页

Stress analysis and structural optimisation of insulating rods under dynamic and static loads 动态和静态载荷下绝缘棒的应力分析和结构优化

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-30 DOI: 10.1049/hve2.12512

Haifeng Jin, Lijun Jin

{"title":"Stress analysis and structural optimisation of insulating rods under dynamic and static loads","authors":"Haifeng Jin, Lijun Jin","doi":"10.1049/hve2.12512","DOIUrl":"https://doi.org/10.1049/hve2.12512","url":null,"abstract":"This study aims to provide a theoretical basis for the fatigue characteristics and structural optimisation of insulating rods to enhance their reliability and lifespan in practical applications. This paper uses COMSOL to complete the stress analysis of insulating rods under dynamic and static loads based on the finite element method. The correctness of the model is verified based on the elastic-plastic theory. The simulation results show that under the same load, the stress concentration area is more affected by the dynamic load, and the stress concentration position is highly consistent with the fracture position of the rod in the experiment. It verifies the impact on the insulating rods at different speeds and static load stress. Simulation shows that, in cases where the allowable stress is exceeded, as the number of operations increases, the fatigue characteristics will greatly affect the service life of the insulation rod. Finally, the fatigue analysis and structural optimisation of the insulating rod were completed, providing important reference values for the long-term stable operation of ultra-high voltage circuit breakers.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 1","pages":"116-125"},"PeriodicalIF":4.4,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12512","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536085","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

Positive corona discharge of rod-plate electrodes in high-speed airflow 高速气流中棒板电极的正电晕放电

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-28 DOI: 10.1049/hve2.12514

Qiang Wu, Yu Wang, Zhengxian Du, Zeliang Wu, Yeqiang Deng, Xishan Wen

{"title":"Positive corona discharge of rod-plate electrodes in high-speed airflow","authors":"Qiang Wu, Yu Wang, Zhengxian Du, Zeliang Wu, Yeqiang Deng, Xishan Wen","doi":"10.1049/hve2.12514","DOIUrl":"https://doi.org/10.1049/hve2.12514","url":null,"abstract":"The characteristics of positive corona discharge of rod electrode in high-speed airflow are studied in this paper. The experiments were carried out in a wind tunnel with a maximum flow speed of 100 m/s in a dark room. The discharge voltage and current were recorded and the corona patterns were captured by a digital single lens reflex (DSLR) camera during the experiment. A discharge transition in rod electrode from streamer corona to mixed streamer-glow corona, and finally to stable glow discharge was observed with the voltage increased. The increase of airflow speed resulted in a decrease of each corona inception voltages. The streamers will be suppressed and shifted towards the upwind side, while the glow layer will be promoted and shifted towards the downwind side in low and upwind side in high voltages. The glow corona current and the voltage show a quadratic function and the higher the airflow speeds, the bigger the coefficient of square of voltage. The distributions of peaks, pulse widths and interval times of streamer pulses were analysed, showing good correspondence with the streamer images. The measurements were explained by combining particle transport and local air pressure distribution.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 2","pages":"337-350"},"PeriodicalIF":4.4,"publicationDate":"2024-12-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12514","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143893002","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

Mechanism and suppression of breaking overvoltage of DC circuit breakers 直流断路器分断过电压的机理及抑制

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-28 DOI: 10.1049/hve2.12491

Lu Qu, Zhangqing Yu, Zhizheng Gan, Xin Yan, Cheng Jiang, Yulong Huang, Mingshen Li, Jian Feng

引用次数: 0

Insulator defect detection under extreme weather based on synthetic weather algorithm and improved YOLOv7 基于合成天气算法和改进YOLOv7的极端天气下绝缘子缺陷检测

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-25 DOI: 10.1049/hve2.12513

Yong Yang, Shuai Yang, Chuan Li, Yunxuan Wang, Xiaoqian Pi, Yuxin Lu, Ruohan Wu

{"title":"Insulator defect detection under extreme weather based on synthetic weather algorithm and improved YOLOv7","authors":"Yong Yang, Shuai Yang, Chuan Li, Yunxuan Wang, Xiaoqian Pi, Yuxin Lu, Ruohan Wu","doi":"10.1049/hve2.12513","DOIUrl":"https://doi.org/10.1049/hve2.12513","url":null,"abstract":"Efficient and accurate insulator defect detection is essential for maintaining the safe and stable operation of transmission lines. However, the detection effectiveness is adversely impacted by complex and changeable environmental backgrounds, particularly under extreme weather that elevates accident risks. Therefore, this research proposes a high-precision intelligent strategy based on the synthetic weather algorithm and improved YOLOv7 for detecting insulator defects under extreme weather. The proposed methodology involves augmenting the dataset with synthetic rain, snow, and fog algorithm processing. Additionally, the original dataset undergoes augmentation through affine and colour transformations to improve model's generalisation performance under complex power inspection backgrounds. To achieve higher recognition accuracy in severe weather, an improved YOLOv7 algorithm for insulator defect detection is proposed, integrating focal loss with SIoU loss function and incorporating an optimised decoupled head structure. Experimental results indicate that the synthetic weather algorithm processing significantly improves the insulator defect detection accuracy under extreme weather, increasing the mean average precision by 2.4%. Furthermore, the authors’ improved YOLOv7 model achieves 91.8% for the mean average precision, outperforming the benchmark model by 2.3%. With a detection speed of 46.5 frames per second, the model meets the requirement of real-time detection of insulators and their defects during power inspection.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 1","pages":"69-77"},"PeriodicalIF":4.4,"publicationDate":"2024-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12513","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536095","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

Adhesion characteristics of carbon particles on the surface of epoxy resin in insulating oil under DC electric field and influencing factors 直流电场作用下绝缘油中环氧树脂表面碳颗粒的附着特性及影响因素

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-23 DOI: 10.1049/hve2.12499

Zijian Dong, Zhanlong Zhang, Jiarong Zhong, Zhixuan Xue, Yu Yang, Zhicheng Pan, Jin Fang

{"title":"Adhesion characteristics of carbon particles on the surface of epoxy resin in insulating oil under DC electric field and influencing factors","authors":"Zijian Dong, Zhanlong Zhang, Jiarong Zhong, Zhixuan Xue, Yu Yang, Zhicheng Pan, Jin Fang","doi":"10.1049/hve2.12499","DOIUrl":"https://doi.org/10.1049/hve2.12499","url":null,"abstract":"The adhesion of carbon particles on the surface of epoxy resin in insulating oil is a significant factor contributing to surface flashover. However, there is currently a lack of a dynamic model that can reasonably explain the adhesion process of impurity particles, and the characteristics of particle adhesion are not yet clear, making it difficult to assess the risks of insulation contamination and surface flashover of valve-side bushing capacitance core. In this study, based on the Johnson–Kendall–Roberts (JKR) theory and the normal distribution characteristics of particle charges, the adhesion probability model of conductive particles in insulating oil on the surface of epoxy resin under DC electric fields was established, and carbon particle adhesion experiments were conducted to verify the accuracy of the model. The impact of electric field intensity, particle size, particle charge, and surface energy of the insulation material on the adhesion characteristics of carbon particles was investigated using the proposed model. The results can be utilised for the assessment of insulation contamination risks of valve-side bushing capacitance core and serves as a vital theoretical foundation for guiding the optimisation of anti-contamination structures in internal insulation and the development of advanced pollution-resistant and flashover-resistant insulation materials.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 2","pages":"505-516"},"PeriodicalIF":4.4,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12499","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143892846","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

Effect of nanostructured SiO2 on charge capture performance and electrical ageing life of PP nanocomposites 纳米SiO2对PP纳米复合材料电荷捕获性能和电老化寿命的影响

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-23 DOI: 10.1049/hve2.12509

Junguo Gao, Liwei Liu, Guangwei Zhang, Tingtai Lee, Uwe Schachtely, Hitoshi Kobayashi

{"title":"Effect of nanostructured SiO2 on charge capture performance and electrical ageing life of PP nanocomposites","authors":"Junguo Gao, Liwei Liu, Guangwei Zhang, Tingtai Lee, Uwe Schachtely, Hitoshi Kobayashi","doi":"10.1049/hve2.12509","DOIUrl":"https://doi.org/10.1049/hve2.12509","url":null,"abstract":"To guarantee the reliability of high-performance and environmentally friendly novel polypropylene (PP) for use as the primary insulation in cables, an assessment of the electrical ageing life of SiO2/PP composite materials was carried out using a step-stress accelerated ageing test based on the inverse power law. The study involved an analysis of microstructural characteristics and performance testing to investigate the bonding between the SiO2 under different surface treatment methods and matrixes. Furthermore, the impact of SiO2 on charge capture performance in PP insulation was analysed through polarisation–depolarisation current testing. The results show that silica with long alkane chains and amino groups grafted on the surface has good compatibility with PP insulating layers, which can increase the trap energy level of captured electrons and thus reduce the damage of high-energy electrons to the composites. SiO2 increased the life index of the PP insulating layer by 19.95%, which contributed to the improvement of the electrical ageing life of the PP insulating layer.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 1","pages":"186-196"},"PeriodicalIF":4.4,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12509","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536064","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

Fast evaluation on the fatigue level of copper contact wire based on laser induced breakdown spectroscopy and supervised machine learning for high speed railway 基于激光诱导击穿光谱和监督机器学习的高速铁路铜接触线疲劳程度快速评估

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-20 DOI: 10.1049/hve2.12492

Wenfu Wei, Langyu Xia, Zefeng Yang, Huan Zhang, Like Pan, Jian Wu, Guangning Wu

{"title":"Fast evaluation on the fatigue level of copper contact wire based on laser induced breakdown spectroscopy and supervised machine learning for high speed railway","authors":"Wenfu Wei, Langyu Xia, Zefeng Yang, Huan Zhang, Like Pan, Jian Wu, Guangning Wu","doi":"10.1049/hve2.12492","DOIUrl":"https://doi.org/10.1049/hve2.12492","url":null,"abstract":"High-strength copper contact wire is of great significance to the electrified railway power supply system, which constantly provides electric power to the trains during operation. However, contact wire is subject to pressure, vibration, and natural forces such as wind, rain, ice, etc. which inevitably result in mechanical fatigue over time. This mechanical fatigue can lead to a decrease in the mechanical strength of the contact wire, and ultimately lead to problems such as wire detachment, fracture, or breakage, posing a serious safety hazard to the electrified railway system. Herein, the authors propose a strategy using nanosecond pulsed laser induced breakdown spectroscopy (LIBS) combined with machine learning technique to realise a fast evaluation on the fatigue level of copper contact line. Three different fatigue levels of copper samples have been made related with the requirement of operational conditions, and a total of 898 LIBS spectra were collected. Twenty-four combinations of spectral pre-processing, feature extraction, and optimisation algorithms were used to compare the recognition results with the accuracy, recall rate, and time cost taken into accounted. Results have shown that the standard normal variable transform–principal component analysis–genetic algorithm improve support vector machine (SNV-PCA-GASVM) model have presented a most satisfactory performance than the others. The cross-validation accuracy of the SNV-PCA-GASVM model was 92.97% while the dimensionality of input variables was reduced by 99.62%. This work is useful for the safety operation of power supply system in high speed railway, and technique development concerning the fast evaluation on materials fatigue in other industrial fields.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 6","pages":"1302-1310"},"PeriodicalIF":4.4,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12492","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143252958","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

A novel thyristor-based hybrid DC circuit breaker with short arcing capability 一种新型的具有短弧能力的晶闸管混合直流断路器

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-20 DOI: 10.1049/hve2.12496

Guanlong Jia, Yuchen Yuan, Hongjiang Guo, Xiaoxue Wang, Feng Niu

{"title":"A novel thyristor-based hybrid DC circuit breaker with short arcing capability","authors":"Guanlong Jia, Yuchen Yuan, Hongjiang Guo, Xiaoxue Wang, Feng Niu","doi":"10.1049/hve2.12496","DOIUrl":"https://doi.org/10.1049/hve2.12496","url":null,"abstract":"Multi-terminal flexible high-voltage direct current (HVDC) transmission and DC grid technology are developing rapidly. The hybrid DC circuit breaker (HCB) has broad application prospects in the field of HVDC transmission and DC power grid. Nevertheless, existing HCBs have one or more following blemishes: arc suppression scheme of mechanical switch, high cost and unreliable adaptive reclosure. In this paper, a modified thyristor-based hybrid DC circuit breaker with short arcing capacity (SA-HCB) is introduced, which consists of the main branch, the fault handling branch and the pre-charging branch. Besides, the modified SA-HCB has the inherent capability of adaptive reclosing. The advantages of thyristors are fully used in the SA-HCB, such as low cost, low conduction voltage drop, and natural shutdown. The detailed structure diagram and mathematical model of the SA-HCB are introduced, and the operation processes of the fault current transfer are also analysed. Later, a design method for parameters of the proposed SA-HCB is provided. Then, a single-ended equivalent system is built in PSCAD/EMTDC to verify the accuracy of the theoretical analysis and parameter design. Subsequently, based on four-terminal simulation, the economy of the SA-HCB is verified by comparing with the topology proposed by ABB. Finally, the small-scale experiment of the proposed SA-HCB is introduced.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"9 6","pages":"1288-1301"},"PeriodicalIF":4.4,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12496","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143252957","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

Research on influence of double energy absorptions on dynamic volt-ampere characteristics of metal oxide varistors 双能量吸收对金属氧化物压敏电阻动态伏安特性影响的研究

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-19 DOI: 10.1049/hve2.12495

Chen Long, Yifei Wu, Yi Wu, Mingzhe Rong, Yu Xiao, Yunfan Bai

{"title":"Research on influence of double energy absorptions on dynamic volt-ampere characteristics of metal oxide varistors","authors":"Chen Long, Yifei Wu, Yi Wu, Mingzhe Rong, Yu Xiao, Yunfan Bai","doi":"10.1049/hve2.12495","DOIUrl":"https://doi.org/10.1049/hve2.12495","url":null,"abstract":"Metal oxide varistors (MOVs) are extensively employed in DC circuit breakers (DCCBs) to suppress overvoltage, dissipate energy and build up voltage after interruption. Despite their widespread use, the performance of MOVs under short-time, double energy absorption conditions is not well understood, posing a challenge to their application in open-close-open (OCO) operations of DCCBs. In this paper, a MOV double energy absorption test platform is established to investigate the deviation in volt-ampere characteristic. The Fréchet distance is proposed as the criterion for assessing the similarity of MOV dynamic volt-ampere characteristics, and the influencing factors are studied. It is observed that a 15% increase in the absorption of rated energy may result in roughly 20-unit rise in the Fréchet distance. Furthermore, the deviation in volt-ampere characteristics during the second pulse is found to be independent of the time interval, affirming that the OCO operation within 300 ms constitutes an adiabatic process. The excursion of the volt-ampere characteristics is dominated by the energy and remains unaffected by the peak current of the initial pulse. These findings lay the foundation for the subsequent MOV dynamic characteristic balance test and model modification.","PeriodicalId":48649,"journal":{"name":"High Voltage","volume":"10 1","pages":"78-87"},"PeriodicalIF":4.4,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1049/hve2.12495","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143535797","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

Detection of characteristic component H2S in SF6 and SF6/N2 mixture using cavity ring-down spectroscopy 用腔衰荡光谱法检测SF6和SF6/N2混合物中的特征组分H2S

IF 4.4 2区工程技术

High Voltage Pub Date : 2024-12-18 DOI: 10.1049/hve2.12508

Anhao Jiang, Chaohai Zhang, Min Zhu, Xiaoxing Zhang

{"title":"Detection of characteristic component H2S in SF6 and SF6/N2 mixture using cavity ring-down spectroscopy","authors":"Anhao Jiang, Chaohai Zhang, Min Zhu, Xiaoxing Zhang","doi":"10.1049/hve2.12508","DOIUrl":"https://doi.org/10.1049/hve2.12508","url":null,"abstract":"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.","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}

引用次数: 0