2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)最新文献

{"title":"Creeping Discharges at Liquid/solid and Gas/Solid Interfaces: Analogies and Involving Mechanisms","authors":"A. Beroual","doi":"10.1109/ICDL.2019.8796829","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796829","url":null,"abstract":"This paper is a synthesis of acquired results by my group on creeping discharges at fluid/solid interfaces during the last two decades. It aims to evidence the analogies between the characteristic parameters of surface discharges propagating on liquid/solid and gas/solid interfaces (namely, shape, stopping length, current/electrical charge, fractal dimension) and the dependency of these characteristics on the same physical parameters. It also evidences the influence of the capacitive effects on these characteristics under different types of voltage waveforms namely AC, DC and lightning impulse voltages.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126959955","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}

{"title":"Increased Loadability of Transformers Immersed in Natural Ester","authors":"F. Scatiggio, F. Pepe, Simone Sacco, C. Serafino","doi":"10.1109/ICDL.2019.8796759","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796759","url":null,"abstract":"Mineral-base oil has been the main insulating liquid for filling power transformers since the 1900’s due to its ready worldwide availability, low cost and good properties. Anyway, in recent times the new desires for a safer non-flammable, an environmental acceptable and a less impacting on sustainable common resources fluid has driven many users in the research and use of alternative fluids to mineral oil. Despite the availability of other fluids, the synthetic and natural (from vegetable seeds) esters (NE) represent the major alternative to mineral insulating oils. Terna as Italian Transmission System Operator (TSO) in according to European Union Directive 2001/42/EC should aim at guaranteeing high levels of environmental protection and safety, so Terna is also aware of its responsibility towards the community and has translated this into a single strategy: to find the right balance between the country’s energy needs, nature conservation and the safeguarding of Italy’s cultural heritage. In addition to the environmental and fire safety benefits, the review of the possible advantages of natural ester-filled transformers allowed identifying alternative design criteria with relevant financial benefits. The TERNA goal was to increase the loading ability of their transformers, mainly by enhancing a much higher limit for overloading in comparison to traditional transformers. For this prototype TERNA selected a 400/135 kV 250 MVA autotransformer, a standard practice for their network. To explore the superior thermal class of the new insulation system, the transformer manufacturer confirmed the possibility of designing this transformer with a “permanent additional capacity”. Five autotransformers with NE are already in service and in its next-2-years strategic plan Terna has planned the installation of more than 20 new power autotransformers filled with natural ester","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131534380","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}

{"title":"Study of the Dielectric Behavior of HFE-7000 in function of Electric Field and Temperature Variations","authors":"Michelle Nassar, N. Chauris, P. Traoré, J. Yagoobi, Anny Michel, M. Daaboul, C. Louste","doi":"10.1109/ICDL.2019.8796845","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796845","url":null,"abstract":"Nowadays, heat transfer enhancement devices are becoming very essential in many applications. Most of electronic devices, from the simplest to the most sophisticated, contain processors. Advanced processors require efficient cooling for an optimal performance. Due to the growing interest in faster and lighter devices, researchers always seek to innovate and optimize cooling strategies. In spatial applications, the use of typical cooling systems can cause complications due to the vibrations during takeoff and due to zero gravity effects. Electrohydrodynamic (EHD) pumping, which is based on the interaction of a dielectric liquid with an electric field, could present a solution to all these challenges. EHD pumps were considered a breakthrough in the field of cooling since they demonstrate many advantages over other types of pumps. EHD devices are less power consuming, lighter and cheaper. They don’t have moving parts and they are suitable for microgravity applications. The hydrofluoroethers (HFE) are dielectric liquids that could be ideally utilized in these pumps for many applications. Being dielectric fluids with eco-friendly properties, HFEs could replace CFCs, HFCs, HCFCs, and PFCs. Due to their promising EHD applications, studies must be done to investigate the variation of their dielectric behavior with electric field and with temperature. This work presents an experimental investigation of the dielectric characteristics of HFE-7000 with temperature variations. Understanding this aspect can help enhance and optimize the performance of EHD systems.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126448916","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}

{"title":"Investigation of AC breakdown strength and frequency varied dielectric response of the non-conventional vegetable oil","authors":"Mrutyunjay Maharana, Niharika Baruah, S. K. Nayak, N. Sahoo, M. Chakrobarty","doi":"10.1109/ICDL.2019.8796833","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796833","url":null,"abstract":"Vegetable oil (VO) based liquid dielectric are gradually being implemented to improve the heat transfer in electrical appliances to enhance their life and improve efficiency. The conventional VO based insulating oil is being moderately researched to improve the understanding of the physical mechanisms involved in their enhanced performance compared to the existing mineral oil (MO) based transformer oil (TO). Despite of all the superior thermophysical and electrical performance of the conventional VO reported in few studies in the context of TO, its vast consumption as edible purpose may limit its application as liquid insulation. Therefore, in this study, a non-conventional VO such as pongamia oil methyl ester (POME) is chosen to be a liquid insulation for transformer. In this paper, the investigation is carried out to evaluate the AC breakdown voltage (ACBDV) of the POME and also the dielectric responses of POME at varying frequency is analyzed at transient condition. POME is extracted from the pongamia crude oil by two step transesterification process followed by refined bleached and deodorization. To understand the comparative enhancement in dielectric integrity, ACBDV analysis of MO and POME is carried out at a line frequency of 50 Hz as per ASTM 1816. The dielectric response such as AC resistivity and relative permittivity of the POME is studied from 50 Hz to 10 MHz. It is observed from the study that the mean BDV of the POME is superior than the MO. Moreover, to detect the probability of failure in ACBDV at different percentage such as 5, 10, 50 and 63.2%, Weibull statistical analysis of the ACBDV is carried for POME and MO. With the rise of frequency from 50 Hz to 10 MHz, the AC resistivity is observed to degrade for both the insulating oils. However, at higher frequency, the resistivity of the POME is not significantly altered and hence making the POME stable in dielectric response at higher frequencies. From the above study, the non-conventional VO and its suitable application in transformer as insulating liquid is a possible option for an efficient insulation.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"102 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123041506","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}

{"title":"Natural ester liquid-filled transformers power the Olympic Games","authors":"K. Rapp, Revin Wang, A. Sbravati, R. I. da Silva, V. Tumiatti, M. Pompili","doi":"10.1109/ICDL.2019.8796513","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796513","url":null,"abstract":"This paper will present natural ester transformer operating data with liquid test results from the units since installation. Various facts and experiences from transformers of two Olympic cities will be shared. The results of physical-chemical and electrical testing including dissolved gas analysis will provide the performance history in the field of a group of power transformers of 138 kV design and of unique designed submersible 10 kV distribution units filled with natural ester fluid, some in service for more than 4 years.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127314694","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}

{"title":"Computation the Effective Dielectric Constant of Nano-Probe Local Surrounding by Solvatochromic Spectral Shift Measurement of Organic Dye Molecule","authors":"A. Stepko, P. Lebedev-Stepanov","doi":"10.1109/ICDL.2019.8796803","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796803","url":null,"abstract":"Computer modeling the dielectric properties of the cucurbit [7]uril (CB [7]) cavity based on the Onsager-Liptay model was carried out by analyzing the solvatochromic shift of the absorption spectrum of 1-(3ammoniumpropyl) -4-[(E) -2-(3,4-dimethoxyphenyl) ethynyl]pyridinium upon the formation of the inclusion complex with CB [7] in a water solution. The CB [7] cavity was considered as a polar environment into which the dye chromophore is placed. Positions of the maxima of the dye absorption spectra were measured experimentally in the following solvents: methanol, ethanol, i-propanol, n-butanol and water with known dielectric and optical properties. These values were used for parametrization of the Onsager-Liptay equation. Quantum-chemical calculations were used to determine molecular structures, dipole moments of the ground and excited states, and polarizability of the dye. Theoretical value of the effective dielectric permittivity of the cavity is in good agreement with the literature data derived by another method. Thus, we propose a new method for investigation the dielectric constant both in bulk liquids and in very small liquid volumes, for example, into picoliter droplets.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123555312","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}

{"title":"Advances in Measuring Partial Discharge in Insulating Liquids","authors":"L. Calcara, M. Pompili, S. Sangiovanni, B. Pfeiffer, T. Renaudin, T. Welfonder","doi":"10.1109/ICDL.2019.8796779","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796779","url":null,"abstract":"The IEC 61294 Technical Report, published in 1993, describes a simple test procedure to measure the PD Inception Voltage (PDIV) in insulating liquids and doesn’t cover any other items related to the PD patterns and their evolution at higher voltages. This simplified approach should be considered superseded when taking into account the several studies published in the last decades concerning the PD detection in different dielectric liquids using PD patterns and Ultra Wide Band measuring systems with the aim to find a correlation between PD phenomena, breakdown event and liquid characteristics. The use of these advanced PD patterns and Ultra Wide Band detectors may also contribute to discriminate PD in insulating liquids and PD in regular voids in oil-paper insulations.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116085586","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}

{"title":"Space Charge Effect On The Electrophysical Characteristics Of Liquid Dielectrics","authors":"B. Dikarev, G. Karasev, S. Sokolovsky, Oleksii Karasev","doi":"10.1109/ICDL.2019.8796821","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796821","url":null,"abstract":"Liquid dielectrics are extensively used as an insulating and heat transfer agent in electrical apparatus. The electophysical properties of these insulating liquids are of vital importance to the service life of electrical equipment and have become increasingly important as operating voltages have increased to 500 kV and above and internal equipment spacing has decreased. We initially studied the current time characteristics of benzene, toluene and carbon tetrachloride under dc electric stress. The results demonstrated that the current decreased with the time, what could be explained by the creation of space charge near the electrodes. Current-voltage characteristics were constructed for different times of electrical field application. We have also conducted measurements of discharge currents, which led to obtaining the values of diffusion coefficient and space charges. From the reversal currents investigations it is possible to calculate the mobility of charge carriers. We added also the new data about reversal currents in hydrolique liquids. The model explaining the dependence of the resistivity on the distance between the electrodes is proposed.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114586030","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}

{"title":"Fire simulation tests of mineral oil and natural esters transformers","authors":"M. Mazzaro, D. De Bartolomeo, M. Pompili, L. Calcara, S. Sangiovanni, F. Scatiggio, A. Valant, M. Rebolini, A. Ledda, E. Bemporad, S. Berardi, F. Mauri, M. Salvadori, A. Sturchio, M. Falconi","doi":"10.1109/ICDL.2019.8796788","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796788","url":null,"abstract":"This paper describes the work carried out by the Italian Institutional Working Group on Natural Esters; this Group has been promoted by the University of Roma ”La Sapienza”, the National Firefighters Authority, the National Institute for Insurance against Accidents at Work (INAIL) and the Department for Geological Survey of Italy (ISPRA) with the objective of further validating the real possibility of risk mitigation for humans and environment through a more widespread use of a new generation of transformers insulated with natural ester liquids. A useful contribution to the activities of the Italian Institutional Group on Natural Esters has been also given by the participation of some of the major players in the electrical sector, such as: Italian TSO, main Distributors, Natural Ester producers and transformer manufacturers. The development of this Italian Group at international level has been the set-up of the CIGRE WG D1.68 “Natural and synthetic esters - Evaluation of the performance under fire and the impact on environment”, which is actually preparing a report on this subject. The present paper reports the main results of experimental comparative fire simulations of both mineral oil and natural esters distribution transformers.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123504220","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}

{"title":"Insulation Characteristics of Spacer Filled with Different Gas insulating mediums Under Superimposed Voltage of DC and Impulse","authors":"Jingrui Wang, Zhiyuan Wang, Jian Wang, Yanan Chang, Qiuxiang Hu, Xiaoru Ni, Qingmin Li","doi":"10.1109/ICDL.2019.8796770","DOIUrl":"https://doi.org/10.1109/ICDL.2019.8796770","url":null,"abstract":"The analysis of the influence of different dielectric gases on the flashover characteristics of insulators under DC voltage superimposed impulse voltage is mainly performed in this paper. In the experiment, the spacer surface charge is saturated by applying DC voltage under working temperature in advance. The flashover experiments were conducted with and without linear metal particle in pure $mathrm {SF_{6}, C_{4}F_{7}N/CO_{2}}$(4%/96%) and $mathrm {SF_{6}/N_{2}}$ (20%/80%) gas mixtures. At the same time, the surface potential distribution was measured and analyzed. The results show that the type of the gas medium is not the dominant factor of potential distribution without particle, and there is little difference in different gas environments. When metal particle defects appear on spacer surface, it will cause severe potential distortion and these regions are located around the tip of the particle and coincide with the flashover path. It also has proved that the gas insulating medium has influence on the surface charge accumulation in this circumstance. In $mathrm {C_{3}F_{7}CN/CO_{2}}$ mixture, the minimum potential value is 9954.86V, which is lower than that of others, and the decline percentage of flashover voltage is 16.82%. These indicate that $mathrm {C_{3}F_{7}CN/CO_{2}}$ is better than SF6 and its mixed gas in some respects.","PeriodicalId":102217,"journal":{"name":"2019 IEEE 20th International Conference on Dielectric Liquids (ICDL)","volume":"93 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130052680","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}