• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.10
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• pp.939-946
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• 2001

This study investigates the electrical and collection characteristics of a wide plate spacing electrostatic precipitator (ESP), using a pilot-scale one. Electrical operating characteristics and collection efficiency were measured for various shapes of discharge electrodes. The collection plate spacing ranged from 300 to 550 mm. Results of electrical characteristic and collection efficiency tests as a function of collection plate spacing, discharge electrode type, applied voltage, and particle diameter were obtained. Increasing the collection plate pitch and altering the corona electrode geometry was found to increase the collection efficiencies without increasing input power requirement. The best efficiency is achieved for the discharge electrode of twisted pin type.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.36 no.3
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• pp.280-285
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• 2023

A breakdown voltage and breakdown electric field of the transformer insulating oil of liquid dielectric were studied in uniform electric field and non-uniform electric field and the transformer insulating oil was observed by the process reached breakdown. Insulation performance evaluation of the liquid dielectric was evaluated at the electrode spacing of 2.5 mm under the conditions of domestic and international standards (KS C IEC 60156), so a comparative review was conducted at the electrode spacing of 2.5 mm. When the electrode spacing is 2.5 mm, the average breakdown voltage is 38.5 kV for sphere-sphere electrodes, 26.6 kV for plate-plate electrodes, 22.9 kV for needle-needle electrodes, and 24.3 kV for sphere-needle electrodes. 23.7 kV for the sphere-plate electrode, and 20.7 kV for the needle-plate electrode. From these results, it can be seen that the average value of the breakdown voltage at the electrode spacing of 2.5 mm, in ascending order, is sphere-sphere, plate-plate, sphere-needle, sphere-plate, needle-needle and needle-plate. It was found that the breakdown voltage of the unequal field was lower than that of the equal field.

• Korean Journal of Materials Research
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• v.30 no.11
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• pp.595-600
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• 2020

The photovoltaic properties of perovskite solar cells (PSCs) with a carbon electrode fabricated using different annealing processes are investigated. Perovskite formation (50 ℃, 60 min) using a hot-plate and an oven is carried out on cells with a glass/fluorine doped TiO₂/TiO₂/ZrO₂/carbon structure, and the photovoltaic properties of the PSCs are analyzed using a solar simulator. The microstructures of the PSCs are characterized using an optical microscope, a field emission scanning electron microscope, and an electron probe micro-analyzer (EPMA). Photovoltaic analysis shows that the energy conversion efficiency of the samples fabricated using the hot-plate and the oven processes are 2.08% and 6.90%, respectively. Based on the microstructure of the samples and the results of the EPMA, perovskite is formed locally on the carbon electrode surface as the γ-butyrolactone (GBL) solvent evaporates and moves to the top of the carbon electrode due to heat from the bottom of the sample during the hot plate process. When the oven process is used, perovskite forms evenly inside the carbon electrode, as the GBL solvent evaporates extremely slowly because heat is supplied from all directions. The importance of the even formation of perovskite inside the carbon electrode is emphasized, and the feasibility of oven annealing is confirmed for PSCs with carbon electrodes.

• Journal of Electrochemical Science and Technology
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• v.12 no.3
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• pp.330-338
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• 2021

An integral electrode-bipolar plate assembly, which is composed of electrode, conductive adhesive film (CAF) and bipolar plate, has been developed and evaluated for application with a vanadium redox flow battery (VRB) to decrease contact resistance between electrode and bipolar plate. The CAF, made of EVA (ethylene-vinyl-acetate) material with carbon black or CNT (Carbon Nano Tube), is applied between the electrode and the bipolar plate to enable an integral assembly by adhesion. In order to evaluate the integral assembly of VRB by adhesive film, the resistivity of integral assembly and the performance of single cell were investigated. Thus, it was verified that the integral assembly is applicable to redox flow battery. Through resistance and contact resistance of bare EVA and CAF films on bipolar plate were changed. Among the adhesive films, CAF film coated with carbon black showed the lowest value in through resistance, and CAF film coated with CNT showed the lowest value in contact resistance, respectively. The efficiency of VRB single cell was improved by applying CAF films coated with carbon black and CNT, resulting in the reduced overvoltage in charging process. Therefore, the energy efficiency of both CAF films, about 84%, were improved than that of blank cell, about 79.5 % under current density at 40 mA cm^-2. The energy efficiency of the two cells were similar, but carbon black coated CAF improved the coulomb efficiency and CNT coated CAF improved the voltage efficiency, respectively.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2002.11a
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• pp.125-131
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• 2002

It is very important to assume potential distribution to be generated in electrode environs and grounding resistance by current beforehand, when incoming at grounding electrode to plan efficient grounding facilities In this paper, we analyzed grounding resistance through a simulation experiment by a water tank scaled model electrode of the rectangular earth plate, a theoretical Calculation result of the rectangular earth plate and measurement of grounding resistance buried rectangular earth plate analysing earth surface potential.

• Journal of environmental and Sanitary engineering
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• v.16 no.3
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• pp.87-95
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• 2001

We've been investegated to find the optimum operation condition of electrlysis which have an influance on disposal efficiency of heavy metals. When we electrolyzed the testing wastewaters containing each 250mg/L of Cr and Zn ions, we exerimented with using variables like as pH, NaCl, electrode gap, electric current strength, the number of electrodes, after fastening positive electrode plate with Al, Fe, Ti and negative electrode plate with Stainless Steel Plate.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.482-483
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• 2007

For measurement of dielectric constants, the commercial parallel plate electrodes system with guard-ring electrode have been widely used up to now. The capacitance derived from the parallel plate electrodes capacitor with guard-ring electrode is calculated by the equation of ($C={\epsilon}\;{\cdot}\;\frac{area\;of\;electrod}{distance\;between\;electrodes}$). Therefore, in parallel plate electrode capacitor, the diameter of the guarded electrode, the gap size between guarded electrode and guard ring, and distance between two active electrode should be measured precisely to calculate dielectric constants from the measured capacitance. Consequently their mechanical measurement uncertainties are directly contributed. Especially the air-gap between the electrodes and dielectric specimen at the system must be existed and the measurement error derived from the air-gap is impossible to evaluate as measurement uncertainties. In this study, we analyze the uncertainty of the commercial dielectric constant test cell using 3 kinds CRMs.

• Proceedings of the KIEE Conference
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• 2003.07a
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• pp.280-282
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• 2003

In this paper we tried to analyze through the water tank model to solve these kinds of problems about the square plate earth electrode using general facilities with being compared with the theory formula announced before. The square plate earth electrode that haven't investigated so far is analyzed by being based on laid rod electrode. And the each kind of calculation model was investigated with the experiment of water tank. An experiment of the vertical square Plate electrode about laying depth in the center of the surface of the water has already done with the practical models that have different forms of electrodes.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.10
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• pp.901-907
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• 2004

This study investigate the effect of collection plate velocity on the electrical and collection characteristics of a moving electrode electrostatic precipitator (MEEP). Though a high resistivity fly ash is attached at the collecting electrode, the MEEP has very stable characteristics of voltage and corona current. Collection efficiency, corona current, and overall collection efficiency are increased, as the magnitude of the collection plate velocity increases.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.10
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• pp.749-755
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• 2013

The purposes of this research are to know the optimal gab and electric pressure (voltage) of electrode-plates coated with activated carbon and also to study their arrangement through dust removal efficiency. From the experimental results of attached dust mass at different electrode-plate gab, the frequency of attachment and detachment of dust was more increased as electrode-plate gab was closer. In attached dust mass per unit area of electrode-plate, the farther electrode gab, the more increased. But in total attached dust mass, the closer electrode gab, the more removed. From the experimental results, the optimal electrode arrangement in dust removal chamber was considered that the forward parts of chamber need to be increased the number of electrode-plate, the backward parts to be increased them. The dust attachment have no relation with electric pressure while showing high removal efficiency under condition of 5 kV of voltage and 2 cm of electrode-plates gab.