{"title":"Correlation between current, emitted light, electric field and propagation velocity of positive streamers in liquid dielectrics under AC voltage","authors":"H. Moulai, A. Nacer, A. Beroual","doi":"10.1109/ICDL.2011.6015473","DOIUrl":"https://doi.org/10.1109/ICDL.2011.6015473","url":null,"abstract":"The paper reports on the search of correlations between the current and emitted light signal, electric field, and propagation velocity associated to positive streamers propagating in mineral oil, tetra-ester and toluene, in a point - plane electrode arrangement, under AC voltage. New correlations, especially between the velocity of positive streamers and the current derivative are established. The frequency spectra of different current pulses and emitted lights are also presented.","PeriodicalId":364451,"journal":{"name":"2011 IEEE International Conference on Dielectric Liquids","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127731628","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":"Motion of conductive particles and the effect on AC breakdown strengths of esters","authors":"X. Wang, Z.D. Wang, J. Noakhes","doi":"10.1109/ICDL.2011.6015453","DOIUrl":"https://doi.org/10.1109/ICDL.2011.6015453","url":null,"abstract":"This paper investigated the motion of a metallic cylinder particle of mm size under uniform AC field in three transformer liquids, including a mineral oil, a synthetic ester and a natural ester. The clean transformer liquids were also artificially contaminated by copper particles of μm size, and the relationship between the AC breakdown strengths and the amount of copper particles was determined. It is found that the breakdown voltages of esters are influenced by metallic particles to a less degree than mineral oil. The slower motion of metallic particles in esters of higher viscosities than mineral oil reduce the chance of breakdown, and this might account for the better performance of esters under AC stresses with the existence of metallic particles.","PeriodicalId":364451,"journal":{"name":"2011 IEEE International Conference on Dielectric Liquids","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127865004","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":"Liquid pumping by miniature electrohydrodynamic pump driven by DC voltage","authors":"M. Tański, M. Kocik, Jerzy Mizeraczyk","doi":"10.1109/ICDL.2011.6015458","DOIUrl":"https://doi.org/10.1109/ICDL.2011.6015458","url":null,"abstract":"In this paper the design and performance of the miniature electrohydrodynamic (EHD) pump driven by DC voltage is presented. The EHD pump had a pipe-like shape of the inner diameter of 0.5 mm with two concentric pipe electrodes. The EHD pump was powered by positive high DC voltage (up to 12 kV). When high voltage was applied the net flow of the working liquid was observed. Pumping tests were performed using isopropyl alcohol (CH3)2CHOH as working liquid. The direction of the flow was from the grounded electrode toward the HV electrode. The flow rate and pressure generated by the EHD micropump was measured. The highest flow rate of 0.5 ml/min was obtained for 12 kV of applied voltage. The maximum measured pressure was 500 Pa for applied voltage of 6 kV. Further increasing of the applied voltage led to the formation of gas bubbles in the working liquid and subsequently the decrease in the pumping efficiency. The current-voltage characteristics was measured for open and closed outlet of the micropump. The maximal current of 20 µA was measured for the applied voltage of 12 kV and open outlet of the pump. This corresponds to the power consumption of 240 mW.","PeriodicalId":364451,"journal":{"name":"2011 IEEE International Conference on Dielectric Liquids","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125804504","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}
H. Ihori, M. Takemura, Naoya Masuichi, H. Yoshihara, M. Fujii
{"title":"Electrooptical measurement of electric field in a dielectric liquid containing remanent charges","authors":"H. Ihori, M. Takemura, Naoya Masuichi, H. Yoshihara, M. Fujii","doi":"10.1109/ICDL.2011.6015469","DOIUrl":"https://doi.org/10.1109/ICDL.2011.6015469","url":null,"abstract":"This It is necessary for electrical insulation diagnosis to obtain information about the electric field distribution in insulation materials. We have investigated the measurement of nonuniform electric field vector distributions in liquid dielectrics using an original method based on electrooptic Kerr effect and CT method. We developed a optical system that could measure electric field distributions of the order of a mili-second. In this study, we carried out the electric field in a liquid containing space charge. The change of the optical light intensity was measured when the voltage pulse was applied again after Ts (min.) from first sequence of applied voltage. i.e., by Ts, the amount of charge in liquid was changed. It was well known that the electric field strength in liquid containing charges was not a static field. The change of the electric field caused by charges in liquid was very interesiting. This technique might be help to know the movement of the charge in a liquid.","PeriodicalId":364451,"journal":{"name":"2011 IEEE International Conference on Dielectric Liquids","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121805609","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}