• 한국염색가공학회지
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• 제5권1호
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• pp.26-32
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• 1993

This study is concerned with the graft polymerization of acrylamide onto the surfaces of polyethylene and polyethylene terephthalate films treated with on corona discharge. In the case, peroxides formed by the corona discharge treatment are likely to be the species responsible for initiating the graft polymerization. This treatment produced a continuous charge in wettability and also amid group density on the polymer surface, as evidenced by water contact angle measurement, Fourier-transform infrared spectroscopy in the attenuated total reflectance mode, and electron spectroscopy for chemical analysis. Both of the merely corona-treated film and the subsequently grafted film are discussed as a function of time after treatment and water washings.

• KIEE International Transactions on Electrophysics and Applications
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• 제12C권4호
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• pp.214-219
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• 2002

The influence of ultraviolet (UV) irradiation and corona on the surface degradation of high temperature vulcanized (HTV) silicone rubber used for outdoor insulation through measuring surface voltage decay after corona charging, surface resistivity, contact angle and X-ray photoelectron spectroscopy (XPS) analysis was studied. The surface resistivity calculated by the surface voltage decay was compared with a value directly obtained from the three electrode method having the guard ring electrode. A good agreement between the two methods for surface resistivity was obtained. UV treated specimens showed the slower decrease of surface voltage decay, while the corona exposed specimens showed a dramatically faster decrease. Although both artificial treatments cause the same oxidative products, which was confirmed with XPS, we could distinguish the difference between the reactions of the two treatments by monitoring the surface voltage decay on corona-charged specimen. In addition, we could derive the specific surface states of the silicone rubber treated by accelerated artificial aging factors and the degradation process.

• Bulletin of the Korean Chemical Society
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• 제32권6호
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• pp.1993-1996
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• 2011

The vibronically well-resolved emission spectrum was recorded from the corona discharge of precursor 2,3,4-trifluorotoluene in a corona excited supersonic expansion with a pinhole-type glass nozzle using a long-path monochromator in the visible region. From the analysis of the observed spectrum, we found the evidence of the presence of the difluorobenzyl radicals in the corona discharge of the precursor. A possible mechanism is proposed for the formation of difluorobenzyl radicals in the gas phase on the basis of the observed emission intensity of the difluorobenzyl radicals produced.

• 조명전기설비학회논문지
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• 제25권9호
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• pp.69-74
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• 2011

In this paper, the UV corona camera was developed using the solar blind and Multi Channel Plate(MCP) technology for the target localization of UV image. UV camera developed a $6.4[^{\circ}]{\times}4.8[^{\circ}]$ of the field of view as a conventional camera to diagnose a wide range of slightly enlarged, and power equipment to measure the distance between the camera and the distance meter has been attached. UV camera to measure the discharge count and the UV image was developed, compared with a commercial camera, there was no significant difference. In salt spray environments breakdown voltage was lower than the normal state, thereby discharging the image was rapidly growing phenomenon.

• 한국정보기술응용학회:학술대회논문집
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• 한국정보기술응용학회 2005년도 6th 2005 International Conference on Computers, Communications and System
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• pp.119-122
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• 2005

A algorithm for control and performance of a pulse-density-modulated (PDM) series-resonant voltage source inverter developed for corona-dischange precesses is presented. The PDM inverter produces either a square-wave ac-voltage state or a zero-voltage state at its ac terminals to control the average output voltage under constant dc voltage and operating frequency. Moreover it can achieve zero-current-switching (ZCS) and zero-voltage-switching (ZVS) in all the operating condition for a reduction of switching lost. Even though the corona discharge load with a strong nonlinear characteristics, new high frequency resonant inverter is shown the wide range power control from 5% to 100%.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1479_1480
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• 2009

부분방전시험은 고전압 고정자 권선의 절연상태를 검사, 평가 할 수 있는 중요한 수단이다. 전동기와 발전기에서 일어나는 절연 악화의 징후로써 부분방전이 발생되며 이러한 부분방전 결함의 정확한 위치 확인이 필요하다. 본 논문에서는 회전기 고정자권선의 결함위치를 판정하기위한 Prototype의 코로나 프로브를 설계하고자 Ferrite core를 이용한 Corona Probe를 제작하였으며 모의 결함을 가지는 6.6[kV] 회전기 고정자권선에 적용하여 부분방전펄스를 측정 하였으며 설계된 Probe의 신뢰성을 확인하고자 상용 HFCT센서와 PPM97(Corona Probe)센서를 통하여 검출감도를 비교분석하였다.

• Journal of Korean Society for Atmospheric Environment
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• 제16권E2호
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• pp.79-84
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• 2000

The Electrostatic Precipitator is one of the most favorable device of particulate control systems because of the relatively higher collection efficiency and easier operation/maintenance. However, it requires very high initial coat especially for discharging electrodes and collecting plates. In dealing with such problems, development of optimum design can be one of the solutions. In this study, a bench-scale electrostatic precipitator was operated in terms of collection area and corona power, and its performances were analyzed focusing on collection efficiency. A result of this study, a more advanced approach for designing cost-effective precipitator by promoting corona power at a minimized collection area was proposed.

• 한국인쇄학회지
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• 제14권1호
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• pp.1-15
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• 1996

In this paper, the preparation of lead zirconium titanate(PZT) thin film by sol-gel processing was descried. Thin film coated with thickness of 4${\mu}{\textrm}{m}$ on the stainless steel substrates using the multiple spin-coating process. The crystalline phases of PZT powder and film were investigated by X-ray diffraction pattern and PZT thin film has perovskite structure over 600 C annealing temperature. Corona charging characteristics of the ferroelectric PZT thin film at 600 C were investigated by electrophotographic measurement. A difference in the charging characteristics between positive and negative corona charging was found. The charge acceptance depended in the polarity of corona and the poling of film. According to the D-E hysteresis measurment, PZT thin film can be poled by corona charging without use of top electrode. The remnant polarization in the PZT thin film is generally in the order of 48$\mu$C/$\textrm{cm}^2$. From this results, the ferroelectric PZT thin film will be possible to apply for the add-on type imaging formation.

• 한국대기환경학회지
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• 제18권5호
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• pp.337-344
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• 2002

In this study, we analyzed the NO removal efficiency by the pulsed corona discharge process and investigated the effects of several process variables such as initial concentrations of NO, $H_2O$, and NH$_3$, applied voltage, pulse frequency, diameter of the discharge electrode, and residence time. The removal efficiency of NO increased by the addition of $H_2O$ or NH$_3$, but the changes of initial NH$_3$ and $H_2O$ concentrations did not affect the removal efficiency of NO significantly. With the increases of the applied voltage or the residence time, the removal efficiency of NO increased. In addition, with the increases of the pulse frequency of applied voltage, or the diameter of the discharge electrode, the removal efficiency of NO increased. The experimental results can be used as a basis to design the pulsed corona discharge process to remove NO$_{x}$, SO$_{x}$ and VOCs.OCs.

• 조명전기설비학회논문지
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• 제28권3호
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• pp.78-83
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• 2014

To minimize the financial loss due to power facility malfunction, on-line diagnostic techniques are required to grasp any abnormal state of facilities in the live line as well as devices to diagnose abnormal states of power facility in an easy and prompt manner. This study aims to develop a portable UV detecting system by means of UV sensors for easier and efficient inspection of the degradation state of power facility in a long distance. Accordingly, it includes a simulation of corona discharges that may occur due to degradation of power facility and detection of ultraviolet pulse generation depending on the corona discharge intensity and measuring distance in application of UV sensors. Additionally, the optimal algorithm is determined for its application to the system's degradation diagnosis program based on the measured experiment data.