Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893090
H. B. H. Sitorus, A. Beroual, R. Setiabudy, S. Bismo
Due to their high biodegradability, non-toxicity and fire safety guarantee, vegetable-based oils are considered today as a potential substitute for mineral and synthetic liquids for electrical insulation and especially in high voltage power transformers. However, most of known vegetable oils are derived from food materials (rape-seeds, sunflower, soybeans, palms, corns and others). And one has to be vigilant to the fact that the replacement of mineral oil by natural ester fluids based on “renewably sourced” vegetable oils, does not create new problems as this could cause global food crisis due to diversion of food into insulating material oils or others (fuel). An interesting product can be jatropha curcas oil extracted from the fruits of jatropha curcas plants (“miracle tree”) which is non-food crops. These plants can be grown on marginal or degraded soils (thus avoiding the need to utilize those more fertile soils currently being used by smallholders to grow their staple crops); and it will readily grow in areas where annual rainfall levels are significantly lower than those required by other species such as rape-seeds, sunflower, palm, soybeans, corns and others. This paper presents an experimental study of streamers phenomena in jatropha curcas methyl ester oil (JMEO) and mineral oil (MO) under positive and negative lightning impulse voltages (1.2/50 μs). It is shown that basing on the shape and stopping length of streamers, JMEO could constitute a potential substitute for mineral and synthetic oils for electrical insulation and especially in high voltage power transformers.
{"title":"Comparison of streamers characteristics in jatropha curcas methyl ester oil and mineral oil under lightning impulse voltage","authors":"H. B. H. Sitorus, A. Beroual, R. Setiabudy, S. Bismo","doi":"10.1109/ICDL.2014.6893090","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893090","url":null,"abstract":"Due to their high biodegradability, non-toxicity and fire safety guarantee, vegetable-based oils are considered today as a potential substitute for mineral and synthetic liquids for electrical insulation and especially in high voltage power transformers. However, most of known vegetable oils are derived from food materials (rape-seeds, sunflower, soybeans, palms, corns and others). And one has to be vigilant to the fact that the replacement of mineral oil by natural ester fluids based on “renewably sourced” vegetable oils, does not create new problems as this could cause global food crisis due to diversion of food into insulating material oils or others (fuel). An interesting product can be jatropha curcas oil extracted from the fruits of jatropha curcas plants (“miracle tree”) which is non-food crops. These plants can be grown on marginal or degraded soils (thus avoiding the need to utilize those more fertile soils currently being used by smallholders to grow their staple crops); and it will readily grow in areas where annual rainfall levels are significantly lower than those required by other species such as rape-seeds, sunflower, palm, soybeans, corns and others. This paper presents an experimental study of streamers phenomena in jatropha curcas methyl ester oil (JMEO) and mineral oil (MO) under positive and negative lightning impulse voltages (1.2/50 μs). It is shown that basing on the shape and stopping length of streamers, JMEO could constitute a potential substitute for mineral and synthetic oils for electrical insulation and especially in high voltage power transformers.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"33 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78128903","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893139
A. Beldjilali, Z. Laimeche, Amroun N. Saidi, H. Moulai, M. Saidi
The goal of this paper is to study the transport phenomena occurring in mineral oils used as power transformers insulation. The main issue is to understand and predict the insulation behavior under different operating conditions. It is known that conduction phenomenon is explained through ionic carriers provided by dissociation phenomenon in the bulk of the insulating liquid when it is submitted to high voltage, but the problem is more complex at the metal/insulating liquid interfaces. For example, formation of the multilayer regions of space charge near the electrodes affects strongly the transport phenomenon, charge carriers injection from the metal into the dielectric liquid may be also possible. Using the isothermal charging currents measurements, the aim of the work is to study different metal/insulating liquid interfaces. We have associated various kinds of metallic electrodes (stainless steel, aluminium and brass) with the Borak22 mineral oil. The metal/liquid/metal structures were submitted to a DC voltage and the electrical charging current was measured with high sensitive electrometer. The results show clearly the effect of the barrier injection high for the three interfaces under high or low applied electric fields. Under high ones, this means that in spite of the formation of the Helmholtz and the diffusive layers, the injection phenomenon still exists but measurements under low applied fields allow announcing that charge carriers are injected at metal/insulating liquid interface according to the schottky low, so the electronic conduction remain possible.
{"title":"Study of charge injection phenomenon at the metal/insulating liquid interfaces","authors":"A. Beldjilali, Z. Laimeche, Amroun N. Saidi, H. Moulai, M. Saidi","doi":"10.1109/ICDL.2014.6893139","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893139","url":null,"abstract":"The goal of this paper is to study the transport phenomena occurring in mineral oils used as power transformers insulation. The main issue is to understand and predict the insulation behavior under different operating conditions. It is known that conduction phenomenon is explained through ionic carriers provided by dissociation phenomenon in the bulk of the insulating liquid when it is submitted to high voltage, but the problem is more complex at the metal/insulating liquid interfaces. For example, formation of the multilayer regions of space charge near the electrodes affects strongly the transport phenomenon, charge carriers injection from the metal into the dielectric liquid may be also possible. Using the isothermal charging currents measurements, the aim of the work is to study different metal/insulating liquid interfaces. We have associated various kinds of metallic electrodes (stainless steel, aluminium and brass) with the Borak22 mineral oil. The metal/liquid/metal structures were submitted to a DC voltage and the electrical charging current was measured with high sensitive electrometer. The results show clearly the effect of the barrier injection high for the three interfaces under high or low applied electric fields. Under high ones, this means that in spite of the formation of the Helmholtz and the diffusive layers, the injection phenomenon still exists but measurements under low applied fields allow announcing that charge carriers are injected at metal/insulating liquid interface according to the schottky low, so the electronic conduction remain possible.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"2 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75294932","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893159
C. Lesaint, Celine Babault, K. Liland, L. Lundgaard
Water is an important enemy of an electric insulation system. Water vapour can be absorbed by electrical insulation materials (liquids or solid) and migrate in between the materials to achieve the same relative humidity equilibrium everywhere. Water can reduce withstand voltage of the insulation liquid, initiate partial discharges in wet solids and increase dielectric losses in solids like epoxies, gels, PCB cards and produce dielectric heating. In insulation liquid filled system the water content of the liquid should never be allowed to reach saturation. One failure scenario is when typical oil with significant water content is cooled to a temperature where the water content is above the saturation content, and then water will precipitate and may condensate at cold insulating gaps and give breakdown due to electric field enhancement. Gel samples were investigated in climate chambers in various conditions of humidity and temperature until an equilibrium was reached. Diffusion and absorption of water were measured at different intervals. The aim of the study was to find an appropriate technique/methodology to follow the absorption of moisture in gel as a function of time. Several techniques were tested to determine the moisture content in the gel such as Karl Fischer, weight differences measurement, freeze drying and capacitive relative humidity sensors giving contrasted results. The weight difference method showed “anomaly” indicating bound water, even after equilibrium (measured with the other methods) was reached the weight continued to increase. The use of humidity sensors covered by gel appears to be the most reliable technique.
{"title":"Absorption of water in silicon gel","authors":"C. Lesaint, Celine Babault, K. Liland, L. Lundgaard","doi":"10.1109/ICDL.2014.6893159","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893159","url":null,"abstract":"Water is an important enemy of an electric insulation system. Water vapour can be absorbed by electrical insulation materials (liquids or solid) and migrate in between the materials to achieve the same relative humidity equilibrium everywhere. Water can reduce withstand voltage of the insulation liquid, initiate partial discharges in wet solids and increase dielectric losses in solids like epoxies, gels, PCB cards and produce dielectric heating. In insulation liquid filled system the water content of the liquid should never be allowed to reach saturation. One failure scenario is when typical oil with significant water content is cooled to a temperature where the water content is above the saturation content, and then water will precipitate and may condensate at cold insulating gaps and give breakdown due to electric field enhancement. Gel samples were investigated in climate chambers in various conditions of humidity and temperature until an equilibrium was reached. Diffusion and absorption of water were measured at different intervals. The aim of the study was to find an appropriate technique/methodology to follow the absorption of moisture in gel as a function of time. Several techniques were tested to determine the moisture content in the gel such as Karl Fischer, weight differences measurement, freeze drying and capacitive relative humidity sensors giving contrasted results. The weight difference method showed “anomaly” indicating bound water, even after equilibrium (measured with the other methods) was reached the weight continued to increase. The use of humidity sensors covered by gel appears to be the most reliable technique.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"3 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91372082","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893119
M. Aljure, M. Becerra, B. Jonsson
Nanoparticles mixed with transformer oil can potentially increase the breakdown strength of the base liquid. Unfortunately, the basic physical mechanisms leading to such improvement are still not clear. This paper implements two existing theories to model the electrical conduction of cyclohexane with TiO2 nanoparticles in a needle to plane configuration. The generation and drift of carriers in the liquid are simulated by coupling the continuity equations for electrons, positive ions, negative ions, and nanoparticles with Poisson's equation for the electric field. The current-voltage characteristics are simulated and compared with the case of pure cyclohexane. The nanoparticles are modeled as either absorbers of electrons or as source of shallow traps in the fluid, according to the existing theories. The simulations show that the considered theories predict no significant effect of nanoparticles added to cyclohexane on the conduction current from a negative point electrode in steady state or under transient conditions.
{"title":"Simulation of the electrical conduction of cyclohexane with TiO2 nanoparticles","authors":"M. Aljure, M. Becerra, B. Jonsson","doi":"10.1109/ICDL.2014.6893119","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893119","url":null,"abstract":"Nanoparticles mixed with transformer oil can potentially increase the breakdown strength of the base liquid. Unfortunately, the basic physical mechanisms leading to such improvement are still not clear. This paper implements two existing theories to model the electrical conduction of cyclohexane with TiO2 nanoparticles in a needle to plane configuration. The generation and drift of carriers in the liquid are simulated by coupling the continuity equations for electrons, positive ions, negative ions, and nanoparticles with Poisson's equation for the electric field. The current-voltage characteristics are simulated and compared with the case of pure cyclohexane. The nanoparticles are modeled as either absorbers of electrons or as source of shallow traps in the fluid, according to the existing theories. The simulations show that the considered theories predict no significant effect of nanoparticles added to cyclohexane on the conduction current from a negative point electrode in steady state or under transient conditions.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"82 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80548514","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893117
N. Hill, M. Blaz, M. Kurrat
In this work it is investigated how the shifting of the boiling point of liquid nitrogen influences the discharge voltage in the liquid. The experiments were conducted with ambient pressures of 0.3 MPa at 78.5 K and 0.4 MPa at 81.5 K. Two different electrode settings were used, Rogowski-shaped electrodes for a homogeneous field and a sphere opposite a plane-electrode for an inhomogeneous field. The electrode setup was stressed with lightning impulses at different electrode gaps (2 and 4 mm). Additionally a resistive heater in the bottom electrode generated bubbles on demand in order to investigate the influence of thermally induced bubbles. The measurement results are analyzed by comparing the discharge voltages under consideration of the time to breakdown.
{"title":"Investigation of the influence of boiling point shifting on the breakdown voltage in liquid nitrogen","authors":"N. Hill, M. Blaz, M. Kurrat","doi":"10.1109/ICDL.2014.6893117","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893117","url":null,"abstract":"In this work it is investigated how the shifting of the boiling point of liquid nitrogen influences the discharge voltage in the liquid. The experiments were conducted with ambient pressures of 0.3 MPa at 78.5 K and 0.4 MPa at 81.5 K. Two different electrode settings were used, Rogowski-shaped electrodes for a homogeneous field and a sphere opposite a plane-electrode for an inhomogeneous field. The electrode setup was stressed with lightning impulses at different electrode gaps (2 and 4 mm). Additionally a resistive heater in the bottom electrode generated bubbles on demand in order to investigate the influence of thermally induced bubbles. The measurement results are analyzed by comparing the discharge voltages under consideration of the time to breakdown.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"29 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83731591","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893072
S. Barringer, D. P. Aykas
Electro-hydrodynamic spraying can be used to produce even coverage of oil onto foods and food surfaces, however soybean oil does not charge well and lecithin is one of the few additives that can be used to decrease resistivity in a food system. Changing lecithin content and temperature affects the resistivity, viscosity and surface tension. These parameters, along with voltage and the calculated weber number, affect the spray quality. Soybean oil was sprayed on oil sensitive paper with 0 to 15% lecithin, at 4 to 47°C, 0 to 40kV, to determine droplet distribution. The number of droplets increased with decreasing resistivity, decreasing viscosity, increasing weber number, intermediate lecithin concentration, increasing temperature, increasing voltage, and had a very weak correlation to surface tension. Voltage had the greatest effect on the number of droplets followed by lecithin content and temperature. Thus, 40 kV, 47°C and 10% lecithin produced the smallest droplets.
{"title":"Electro-hydrodynamic spraying of soybean oil","authors":"S. Barringer, D. P. Aykas","doi":"10.1109/ICDL.2014.6893072","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893072","url":null,"abstract":"Electro-hydrodynamic spraying can be used to produce even coverage of oil onto foods and food surfaces, however soybean oil does not charge well and lecithin is one of the few additives that can be used to decrease resistivity in a food system. Changing lecithin content and temperature affects the resistivity, viscosity and surface tension. These parameters, along with voltage and the calculated weber number, affect the spray quality. Soybean oil was sprayed on oil sensitive paper with 0 to 15% lecithin, at 4 to 47°C, 0 to 40kV, to determine droplet distribution. The number of droplets increased with decreasing resistivity, decreasing viscosity, increasing weber number, intermediate lecithin concentration, increasing temperature, increasing voltage, and had a very weak correlation to surface tension. Voltage had the greatest effect on the number of droplets followed by lecithin content and temperature. Thus, 40 kV, 47°C and 10% lecithin produced the smallest droplets.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"35 1","pages":"1-6"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79447334","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893106
T. Umemoto, S. Kainaga, H. Muto, T. Tsurimoto, S. Yoshida, M. Kozako, M. Hikita
This paper deals with the characteristics of partial discharge in oil/pressboard composite insulation system, which is adopted in oil-immersed power transformer. In the insulating structure of the transformer, large oil gaps are often subdivided by pressboard barriers into small ones. Once partial discharge occurs at the point where the electric field is enhanced and progresses, the electric field distribution may change from the static one. As a result, there are possibilities that partial discharge successively occurs at the oil gap across pressboard barrier, which might be the trigger of breakdown of the apparatus. In this study, the authors experimentally observed the partial discharge generation across the pressboard barrier in an element model and examined the mechanism of the above phenomenon.
{"title":"Characteristics of partial discharge in the oil gap separated by pressboard barrier in oil/pressboard composite insulation system","authors":"T. Umemoto, S. Kainaga, H. Muto, T. Tsurimoto, S. Yoshida, M. Kozako, M. Hikita","doi":"10.1109/ICDL.2014.6893106","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893106","url":null,"abstract":"This paper deals with the characteristics of partial discharge in oil/pressboard composite insulation system, which is adopted in oil-immersed power transformer. In the insulating structure of the transformer, large oil gaps are often subdivided by pressboard barriers into small ones. Once partial discharge occurs at the point where the electric field is enhanced and progresses, the electric field distribution may change from the static one. As a result, there are possibilities that partial discharge successively occurs at the oil gap across pressboard barrier, which might be the trigger of breakdown of the apparatus. In this study, the authors experimentally observed the partial discharge generation across the pressboard barrier in an element model and examined the mechanism of the above phenomenon.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"36 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75031872","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893095
Masahiro Sato, A. Kumada, K. Hidaka, K. Yamashiro, Y. Hayase, T. Takano
Silicone gel is widely used to encapsulate power electronic circuits. It is well known that surface discharge in the module is one of the weakest points in insulation. These discharges cause the growth of cavity in silicone gel. We have observed the cavity dynamics in order to investigate the degradation process. The results indicated that streamers propagate through the gaseous phase in filamentary channels from the electrode and reaches the tip of the cavity, and leaves charges until the next discharge occurs. Moreover it was revealed that the propagation of the cavity was caused by the positive discharges. The self-healing ability of gel determined whether the propagation succeeds or not.
{"title":"Degradation process of silicone-gel by internal surface discharges","authors":"Masahiro Sato, A. Kumada, K. Hidaka, K. Yamashiro, Y. Hayase, T. Takano","doi":"10.1109/ICDL.2014.6893095","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893095","url":null,"abstract":"Silicone gel is widely used to encapsulate power electronic circuits. It is well known that surface discharge in the module is one of the weakest points in insulation. These discharges cause the growth of cavity in silicone gel. We have observed the cavity dynamics in order to investigate the degradation process. The results indicated that streamers propagate through the gaseous phase in filamentary channels from the electrode and reaches the tip of the cavity, and leaves charges until the next discharge occurs. Moreover it was revealed that the propagation of the cavity was caused by the positive discharges. The self-healing ability of gel determined whether the propagation succeeds or not.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"41 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76177601","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893168
A. Mercado-Cabrera, R. López-Callejas, R. Peña-Eguiluz, R. Valencia-Alvarado, B. Rodríguez-Méndez, A. Munoz-Castro, B. Jaramillo-Sierra, A. de la Piedad-Beneitez
Nonthermal plasma process of dielectric barrier discharge was successfully applied to experimental phenol degradation in a synthetic waste water aqueous solution. A typical coaxial reactor was disposed vertically but the surface of the high voltage internal electrode was shaped like a hollow screw. This electrode allowed to have a quasi-homogeneous plasma in all the length of the reactor and the inter-electrode space. With this configuration was possible to decrease the typical consumed electric power by the reactor and the liquid temperature at the end of the experience. A 90%Ar-10%O2, 80%Ar-20%O2 or 100%O2 gas mixture flowed across the gas gap and on the liquid surface. The applied electric power was in the range of 18-23 kV at 1.5 kHz. A 100%O2 gas mixture, experimental results showed an enhancement of removal efficiency beyond of 99% compared with a smooth surface cylindrical electrode after 1 hour of treatment. Also, this high efficiency was obtained with lower released power compared with that of smooth surface cylindrical electrode.
{"title":"Enhancement of phenol degradation in aqueous solution by a hollow screw like electrode in gas-liquid DBD","authors":"A. Mercado-Cabrera, R. López-Callejas, R. Peña-Eguiluz, R. Valencia-Alvarado, B. Rodríguez-Méndez, A. Munoz-Castro, B. Jaramillo-Sierra, A. de la Piedad-Beneitez","doi":"10.1109/ICDL.2014.6893168","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893168","url":null,"abstract":"Nonthermal plasma process of dielectric barrier discharge was successfully applied to experimental phenol degradation in a synthetic waste water aqueous solution. A typical coaxial reactor was disposed vertically but the surface of the high voltage internal electrode was shaped like a hollow screw. This electrode allowed to have a quasi-homogeneous plasma in all the length of the reactor and the inter-electrode space. With this configuration was possible to decrease the typical consumed electric power by the reactor and the liquid temperature at the end of the experience. A 90%Ar-10%O2, 80%Ar-20%O2 or 100%O2 gas mixture flowed across the gas gap and on the liquid surface. The applied electric power was in the range of 18-23 kV at 1.5 kHz. A 100%O2 gas mixture, experimental results showed an enhancement of removal efficiency beyond of 99% compared with a smooth surface cylindrical electrode after 1 hour of treatment. Also, this high efficiency was obtained with lower released power compared with that of smooth surface cylindrical electrode.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"63 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77437484","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}
Pub Date : 2014-09-08DOI: 10.1109/ICDL.2014.6893165
D. Ariza, M. Becerra, R. Hollertz, C. Pitois
This paper presents an experimental study of the positive streamer charge in transformer oil and oil-solid interfaces in a point-plane gap (5mm) under impulse voltage 50ns1800μs (maximum peak voltage 24 kV). The experiment is intended to compare the charge of streamers propagating in transformer oil with and without a solid barrier along their path. The solid barrier constricting the streamer volume consists of two parallel strips of either impregnated pressboard or a polymeric film (PA6) installed at both sides of the point electrode. The maximum cumulative charge of the streamer is found for the case when the impregnated pressboard is used and the minimum cumulative charge for the case of the polymer as a barrier.
{"title":"Measurements of the charge of streamers propagating along transformer oil-solid interfaces","authors":"D. Ariza, M. Becerra, R. Hollertz, C. Pitois","doi":"10.1109/ICDL.2014.6893165","DOIUrl":"https://doi.org/10.1109/ICDL.2014.6893165","url":null,"abstract":"This paper presents an experimental study of the positive streamer charge in transformer oil and oil-solid interfaces in a point-plane gap (5mm) under impulse voltage 50ns1800μs (maximum peak voltage 24 kV). The experiment is intended to compare the charge of streamers propagating in transformer oil with and without a solid barrier along their path. The solid barrier constricting the streamer volume consists of two parallel strips of either impregnated pressboard or a polymeric film (PA6) installed at both sides of the point electrode. The maximum cumulative charge of the streamer is found for the case when the impregnated pressboard is used and the minimum cumulative charge for the case of the polymer as a barrier.","PeriodicalId":6523,"journal":{"name":"2014 IEEE 18th International Conference on Dielectric Liquids (ICDL)","volume":"1 1","pages":"1-4"},"PeriodicalIF":0.0,"publicationDate":"2014-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87672832","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}