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2020 IEEE 3rd International Conference on Dielectrics (ICD)最新文献

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Enhancement of Surface flashover performance of epoxy by doping POSS nanofillers 掺杂POSS纳米填料增强环氧树脂表面闪络性能
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341971
Farooq Aslam, Guanghao Qu, Zhen Li, Haoming Xu, Weiwang Wang, Shengtao Li
{"title":"Enhancement of Surface flashover performance of epoxy by doping POSS nanofillers","authors":"Farooq Aslam, Guanghao Qu, Zhen Li, Haoming Xu, Weiwang Wang, Shengtao Li","doi":"10.1109/ICD46958.2020.9341971","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341971","url":null,"abstract":"Surface flashover is key issue to limit the development of high voltage insulation equipment. Various nano-fillers are added to improve the performance of epoxy composites. With the ultimate goal to enhance the surface flashover performance, two different types of polyhedral oligomeric silsesquioxane (POSS) nanometric molecular structure is doped into neat epoxy. Surface flashover voltage has been tested under DC voltage in SF6 gas. Isothermal surface potential decay (SPD) test were conducted to find out the surface charge characteristics. Quantum chemical calculation was performed to investigate the absolute energy value of Lowest Unoccupied Molecular Orbital (LUMO) level for epoxy/POSS composite, associated to electron affinity for charge carriers. Results specifies that flashover voltage has been positively influenced by both trap energy and trap density of charges. While improved flashover performance of EP/OG-POSS composite compared to EP/ECH-POSS and pristine sample is attributed to deep traps for charges. The energy distribution diagram shows that EP/OG-POSS has higher affinity for charge carrier in EP/OG-POSS comparatively. The affinity for carriers assists the charge trapping centers. Moreover, functional properties of POSS side groups can determine the tailoring of deep trap; moreover, the simulated electronic properties are helpful to understand the improved properties of surface flashover voltage.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"21 1","pages":"110-113"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77913686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Investigation of Photovoltaic DC Cable Insulation Integrity under Thermal Stress 热应力作用下光伏直流电缆绝缘完整性研究
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341899
E. Mustafa, Ramy S. A. Afia, Z. A. Tamus
{"title":"Investigation of Photovoltaic DC Cable Insulation Integrity under Thermal Stress","authors":"E. Mustafa, Ramy S. A. Afia, Z. A. Tamus","doi":"10.1109/ICD46958.2020.9341899","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341899","url":null,"abstract":"DC cables account for only 1-2 % of the overall cost of the photovoltaic system but have a significant impact on the output of the power system. During service, the DC cables have to bear harsh conditions as they have to endure high temperatures, mechanical and atmospheric stresses. Out of these stresses, the thermal stress is a constant stress in which the cables are exposed to causing degradation in the insulation and jacket of the cable. This could reduce the service life of the cable insulation and may result in embrittlement, cracking and eventual failure of the insulation, and risking a possible short circuit. This paper has been aimed to study the overall degradation of the low voltage photovoltaic unshielded DC cables under thermal stress by adopting dielectric spectroscopy and hardness as non-destructive condition monitoring techniques. The cables were accelerated thermally aged under 120°C temperature for seven cycles. The insulation and jacket were kept intact and the overall state of the cable was examined. The significant variation in the real and imaginary part of permittivity was observed at low frequency, 0.01 Hz. While with aging the cable became harder, showing the sign of degradation in the cable. The results show the potential capability of the techniques to be used as diagnostic techniques for the low voltage unshielded cables.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"32 1","pages":"13-16"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75138045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","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 the Charge Transport in LDPE with Combined Measurement of Space Charge and Current 结合空间电荷和电流测量分析LDPE中的电荷输运
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341927
Z. Lv, Chen Zhang, Yuntong Ma, Kai Wu, Yonghong Cheng
{"title":"Analysis of the Charge Transport in LDPE with Combined Measurement of Space Charge and Current","authors":"Z. Lv, Chen Zhang, Yuntong Ma, Kai Wu, Yonghong Cheng","doi":"10.1109/ICD46958.2020.9341927","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341927","url":null,"abstract":"Space charge accumulation is an important issue for HVDC cable design. The space charge accumulation are determined by the charge transport property which can be monitored by the space charge and conduction current measurement. In this paper, based on PEA system and three-electrode system, the modified combined measurement system was developed to measure the space charge and current in LDPE samples simultaneously. The results show that the current gradually decreased with the accumulation of homocharges; the generation and movement of space charge packet resulted in the current peaks; the reduction of homocharge accumulation and the increase of heterocharge tends to increase the current.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"55 1","pages":"367-370"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75897700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Non-intrusive Measurement of Transient Electric Field Distribution in HVAC GIL 暖通空调GIL暂态电场分布的非侵入式测量
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341848
J. Li, R. Zhao, T. Tian, Y. Chen, R. Chen, J. He, H. C. Liang, H. Yao, B. Du
{"title":"Non-intrusive Measurement of Transient Electric Field Distribution in HVAC GIL","authors":"J. Li, R. Zhao, T. Tian, Y. Chen, R. Chen, J. He, H. C. Liang, H. Yao, B. Du","doi":"10.1109/ICD46958.2020.9341848","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341848","url":null,"abstract":"Measuring the electric field distribution will provide exact information for the design and the safe operation of electrical devices. A simple but effective technique is developed in this paper to measure the transient electric field distribution by fabricating a micro-sized sensor on the grounded (GND) electrode. Both the parameter selection and the fabrication technique are critical for ensuring the non-intrusive measurement. By experiment, the measured electric fields in time domain have exactly the same waveforms as those of the applied AC and impulse voltages, and their spatial distributions are in good agreement with the theoretical calculation results, which proves the correctness and effectiveness of the measurement system. In the future application, the measurement electrodes of the sensor can be designed to be in smaller size and in array form for a more precise measurement. This technique has the potential to be applied in the electric power system for the dynamic monitoring and the defect location of electrical devices.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"2 1","pages":"629-632"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73043447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Modeling of metallized film capacitors segmented electrodes electrodynamic destruction 金属化薄膜电容器的分段电极电动力学破坏建模
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341865
I. Ivanov, Kirill Voloshin, Kirill Kulbako
{"title":"Modeling of metallized film capacitors segmented electrodes electrodynamic destruction","authors":"I. Ivanov, Kirill Voloshin, Kirill Kulbako","doi":"10.1109/ICD46958.2020.9341865","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341865","url":null,"abstract":"electrodynamic destruction due to electrothermal evaporation of segmented zinc electrodes used in metallized film capacitors was experimentally studied. Numerical model of segmented electrodes electrothermal evaporation was developed using COMSOL Multiphysics software. This model takes into account all necessary electrical and thermal material’s parameters. The results of simulation are in good agreement with experimental data. Numerical model can be used for optimization of segmented electrodes parameters and checking its efficiency.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"19 1","pages":"689-691"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72653187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 2
Fourier Transform Infrared Spectroscopic Analysis of Field Failed 220 kV Polymeric Insulators 220kv现场失效聚合物绝缘子的傅里叶变换红外光谱分析
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341948
Srijib Banerjee, D. Shakthi Prasad
{"title":"Fourier Transform Infrared Spectroscopic Analysis of Field Failed 220 kV Polymeric Insulators","authors":"Srijib Banerjee, D. Shakthi Prasad","doi":"10.1109/ICD46958.2020.9341948","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341948","url":null,"abstract":"Polymeric insulators have shown tremendous growth in their application and are under continuous upgradation since their inception. Insulators undergo several stresses as they are exposed to outer environment and being organic in nature, polymeric insulators degrade because of UV, corona, acid attacks, mechanical and electrical stresses etc. This paper presents the Fourier Transform Infrared (FTIR) spectrum analysis of the failed 220 kV silicone rubber polymeric insulators. The occurrence of different physico-chemical changes in the different shed positions of the failed insulators is studied. The preliminary investigation showed the loss of Alumina Tri Hydrate (ATH) filler from the failed insulator samples. Retention of hydrophobicity have also been reported in the present work.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"24 1","pages":"613-616"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72671602","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Calculation of initial discharge voltage on insulator surface based on the simulation analysis of distorted electric field 基于畸变电场仿真分析的绝缘子表面初始放电电压计算
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341842
Gangjie Zhou, Tao Jiang, Fuchun Chen, Lijun Jin, Xiaokun Man
{"title":"Calculation of initial discharge voltage on insulator surface based on the simulation analysis of distorted electric field","authors":"Gangjie Zhou, Tao Jiang, Fuchun Chen, Lijun Jin, Xiaokun Man","doi":"10.1109/ICD46958.2020.9341842","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341842","url":null,"abstract":"The calculation of initial discharge voltage is the difficulty of insulator performance evaluation. Based on the theory of streamer and the finite element simulation analysis of distorted electric field, the gas discharge model of polluted insulator surface is established in this paper. The electric field distribution in the gap of the dry band was calculated, and the impact of environmental factors such as pollution degree, humidity and temperature on the distribution of distorted electric field is studied. The dynamic process of the initial discharge of streamer is analyzed quantitatively by the finite element methods such as space electric field partition quantification and dynamic accumulation, and the calculation method of the initial discharge voltage on insulator surface is proposed. The calculation method of this paper is verified by the surface discharge experiment of polluted insulator. The experimental results show that the calculation method based on the simulation analysis of distorted electric field and considering the environmental factors can accurately quantify the streamer initial discharge voltage on insulators, which can provide useful reference for the operation and maintenance of power transmission and transformation projects.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"367 1","pages":"158-161"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84915381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 3
Current Integrated Charge Measurement Evaluation of Insulation Layer for Power Module using DC Current Integrated Charge Measurement 直流电流综合电荷测量对电源模块绝缘层电流综合电荷测量的评价
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341898
Y. Tanaka, D. Hanazawa, K. Hijikata, H. Miyake, T. Takada
{"title":"Current Integrated Charge Measurement Evaluation of Insulation Layer for Power Module using DC Current Integrated Charge Measurement","authors":"Y. Tanaka, D. Hanazawa, K. Hijikata, H. Miyake, T. Takada","doi":"10.1109/ICD46958.2020.9341898","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341898","url":null,"abstract":"DC current integrated charge measurement (Q(t) method) is applied to evaluate the performance of insulating layer used in power module at high temperature under high DC stress. It is said that a s pace charge accumulation is one of important factors to evaluate the insulating materials, and the Q(t) measurement is an effective method that is available to the actual devices. Therefore, the Q(t) method was attempted to be applied to evaluate the insulating layers in some actual IGB T modules. As the result, it is found that the Q(t) method is effective to evaluate the insulating materials used for actually devices.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"26 1","pages":"459-462"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84035702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
Decomposition characteristics of C3F7CN under the presence of H2O and O2 based on molecular dynamics 基于分子动力学的C3F7CN在H2O和O2存在下的分解特性
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341872
M. Xiao, X. Feng, Q. Han, Y. A. Wang, B. Du, Y. Zuo, K. Fan, Q. Wangs
{"title":"Decomposition characteristics of C3F7CN under the presence of H2O and O2 based on molecular dynamics","authors":"M. Xiao, X. Feng, Q. Han, Y. A. Wang, B. Du, Y. Zuo, K. Fan, Q. Wangs","doi":"10.1109/ICD46958.2020.9341872","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341872","url":null,"abstract":"SF<inf>6</inf> (Sulfur hexafluoride) was widely used in gas insulated electrical equipment. However, it is a strong greenhouse gas with a GWP (global warming potential) of 23900. In recent years, C<inf>3</inf>F<inf>7</inf>CN (heptafluoro-iso-butyronitrile) was proved to be a potential substitute gas with excellent insulation performance and low greenhouse effect. In this paper, the decomposition of C<inf>3</inf>F<inf>7</inf>CN under the presence of H<inf>2</inf>O and O<inf>2</inf> was studied based on the ReaxFF-MD (reactive force field molecular dynamics). It was found that H<inf>2</inf>O would promote the decomposition of C<inf>3</inf>F<inf>7</inf>CN. Compared with the 130 C<inf>3</inf>F<inf>7</inf>CN molecule remained in the pure C<inf>3</inf>F<inf>7</inf>CN system, the number of C<inf>3</inf>F<inf>7</inf>CN in the adding 50 H<inf>2</inf>O system is 100 at 1000ps. HF, COF<inf>2</inf> were produced in the adding H<inf>2</inf>O systems. The number of HF increased with the number of H<inf>2</inf>O added and there were 34 HF formed in the adding 50 H<inf>2</inf>O system in the end. 1 COF<inf>2</inf> was generated in the adding 30, 50 H<inf>2</inf>O systems. O<inf>2</inf> had no significant effect on the decomposition of C<inf>3</inf>F<inf>7</inf>CN, although a small amount of COF<inf>2</inf> were formed. The simultaneous presence of H<inf>2</inf>O and O<inf>2</inf> promoted the decomposition of C<inf>3</inf>F<inf>7</inf>CN, and it was close to the promotion of pure H<inf>2</inf>O. The number of HF and COF<inf>2</inf> in the adding H<inf>2</inf>O/ O<inf>2</inf> systems were close with that in the adding H<inf>2</inf>O systems. Utilizing molecular dynamics to study the decomposition of C<inf>3</inf>F<inf>7</inf>CN under the presence of H<inf>2</inf>O and O<inf>2</inf> on the provides theoretical support for the study of C<inf>3</inf>F<inf>7</inf>CN gas characteristics.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"52 1","pages":"550-553"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86739630","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Roughness Enhanced Charge Injection and Field Dependent Conduction Mechanisms for Bipolar Charge Transport Models 双极电荷输运模型的粗糙度增强电荷注入和场相关传导机制
2020 IEEE 3rd International Conference on Dielectrics (ICD) Pub Date : 2020-07-05 DOI: 10.1109/ICD46958.2020.9341958
E. Doedens, E. M. Jarvid, Y. Serdyuk
{"title":"Roughness Enhanced Charge Injection and Field Dependent Conduction Mechanisms for Bipolar Charge Transport Models","authors":"E. Doedens, E. M. Jarvid, Y. Serdyuk","doi":"10.1109/ICD46958.2020.9341958","DOIUrl":"https://doi.org/10.1109/ICD46958.2020.9341958","url":null,"abstract":"Extruded HVDC cable systems contain a multitude of different interface types. Physical interfaces are introduced on-site when the outer semi-conductive layer is removed prior to installing a pre-molded joint or stress-cone onto the cable end. Such interfaces are characterized by surface roughness, which can locally enhance electric field and stimulate charge injection at microscale asperities. This work studies the impact of surface roughness on charge injection by performing space charge measurements on cable peelings and evaluating the observed charge evolution with a bipolar charge model. The behavior during both polarization and depolarization stages was investigated. A unique set of conduction and injection parameters is suggested allowing for realistic interpretation of charge accumulation and decay observed in the measurements.","PeriodicalId":6795,"journal":{"name":"2020 IEEE 3rd International Conference on Dielectrics (ICD)","volume":"1 1","pages":"413-417"},"PeriodicalIF":0.0,"publicationDate":"2020-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88768190","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 1
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