한국조명전기설비학회:학술대회논문집 (Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference) (Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference)
한국조명전기설비학회 (The Korean Institute of IIIuminating and Electrical Installation Engineers)
- 기타
과학기술표준분류
- 전기/전자 > 가정용기기/전자응용기기
한국조명전기설비학회 2008년도 춘계학술대회 논문집
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The purpose of this study is to investigate the luminous environment of fluorescent lamp and LED lamp in a office space for various color temperature by subject response test. For this, three different color temperatures were tested for the same illuminance level. Based on such test results for various color temperatures of fluorescent lamp and white LEDs, this study is to analyze the preferences of color temperature and light source, and perceptional brightness of each light source and color temperature. Then, this study is to derive the guidelines for the performance of color temperature which are suitable on the purpose and the mood of a office space.
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ITO thin film is generally fabricated by various. methods such as spray, CVD, evaporation, electron gun deposition, direct current electroplating, high frequency sputtering, and reactive DC sputtering. However, some problems such as peaks, bumps, large particles, and pin-holes on the surface of ITO thin film were reported, which caused the destruction of color quality, the reduction of device life time, and short-circuit. Chemical mechanical polishing (CMP) process is one of the suitable solutions which could solve the problems
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서울 도심의 인적 운송수단의 중심에 있는 지하철
$1{\sim}8$ 호선의 차량 객실조명과 지하철 역사 조명을 조사하여 현재의 조명환경을 파악한 후 각 호선별 지하철 차량의 객실 조도와 휘도를 측정하고 지하에 위치한 역사의 조도를 측정하여 분석하였다. 또한 역사의 기준등급을 환승역은 A등급, 일반역은 B 등급으로 적용하여 기준조도를 선정하였으며 현재의 측정 조도와 사용광원을 검토하여 에너지절약 및 지하철의 조명환경개선을 연구함으로써 이용객에게 쾌적하고 안락한 지하철 조명 환경을 만들고자 한다. -
본 논문에서는 After-market에서 자동차 헤드라이트 상 하향 빔 전환 시스템으로 주로 사용하고 있는 solenoid 방식의 여러 문제점을 개선하기 위하여 차량용 릴레이를 이용한 HID램프의 헤드라이트 상 하향 전환 컨트롤 방식를 제안하였다. 특히, 차종에 따라 달라지는 상 하향 빔 전환 입력신호에 대하여 릴레이가 일정하게 상 하향 동작을 할 수 있는 signal selector회로를 구성하고, 두 개의 램프를 relay로 전환하는 방식을 채택함으로서 그 동안 자동차 하우징 구조상 기존 H4 타입에만 국한되어 오던 차량용 HID램프의 헤드라이트 상 하향 빔 전환 시스템을 H1, H3, H7, H11, 9004, 9006, 9007 등 다른 베이스타입의 벌브에도 적용이 가능하도록 하여 우수한 범용성을 갖도록 하였다.
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Properties of carbon nano fiber (CNF) as field emitters were described. Carbon nano fiber (CNF) of herringbone was prepared by thermal chemical vapor deposition(CVD). Field emitters mixed with organic binders, conductive materials and were prepared by screen-printing process. In order to increase field emissions, the surface treatment of rubbing & peel-off was applied to the printed CNF emitters on cathode electrode. The measurements of field emission properties were carried out by using a diode structure inline vacuum chamber. CNF of herringbone type showed good emission properties that a turn on field was as low as 2.1
$V/{\mu}m$ and current density was as large as 0.15$mA/cm^2$ of 4.2$V/{\mu}m$ with electric field. Through the results. we propose that CNFs are suitable for application of electron emitters in Field Emission Devices. -
수은이 함유된 방전등과 같은 조명기구의 사용이 제한되는 특수구역의 산업용 조명설비로 200 W 이상의 높은 소비전력의 백열등기구들이 사용되고 있다. 인공광원으로 백열전구는 매우 낮은 발광효율로 전력소모가 많고, 높은 방사열로 인해 화재의 염려가 있어 램프보호유리구를 장착하므로 낮은 조명률로 광 손실이 높게 발생한다. 또한 산업지역 내에서는 일반적으로 각종 전동기 및 공기조화 설비의 가동으로 진동이 심하며 여기에 백열전구 사용 시 당초 예상되는 수명보다 더욱 단축되고 있다. 이러한 지역에 설치된 백열등을 조명등기구 효율(Luminaire Efficacy)이 높은 친환경 에너지 절감형 차세대 광원인 LED조명등으로 대체하여 산업설비 지역 내 공급되는 조명용 소비전력을 크게 줄여 에너지 절약효과를 높임과 동시에 양호한 조명율의 LED광원을 사용함으로써 조명환경 개선에 따른 작업능률을 높이기 위해 특수지역의 산업용 LED조명등을 개발하였다.
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The electron charging and degradation of anode phosphor layers are showed major problems in high electric field with anode electrode of field emission devices. An AI metal layer on the phosphor layer may get rid of these problems. This Hetero-metal-oxide phosphor layer are formed with the roughness of phosphor surface layer without interlayer and cannot be given rise to enhance the luminance efficiency. In order to enhance the brightness, an anode layer need to be flated between phosphor layer and AI metal layer in anode electrode. After optimizing the anode phosphor layer, an anode layer with AI metal and inter layer increased the brightness and luminescence efficiency 1.2 times more than only phosphor laver in anode.
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PDP의 구동기술로서 가장 많이 사용되고 있는 ADS구동법은 어드레스 방전시 방전지연(discharge time delay)이 발생한다. 따라서 어드레서(address) 펄스의 폭이 충분히 넓어야 높은 휘도에서 균일한 방전을 할 수 있어 현재 고화질화에 많은 어려움을 갖고 있다. 본 논문에서는 어드레스 기입 시간에 따라 발생하는 방전지연시간에 대해 연구하였다. 그 결과 프라이밍(priming) 방전과의 시간차가 증가하면 방전지연시간이 증가하여 방전이 불안정해진다는 것과 어드레스 펄스 타이밍의 실제 표시방전 기간에 거의 영향을 미치지 않는다는 것을 측정결과로 확인하였다.
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This paper presents the results of a simulation to analyze the effects of voltage sag on high-pressure discharge lamp(400[W]). In this paper, voltage sag is considered a reduction between 0 and 0.9[p.u] in nominal voltage magnitude, with duration between 0.01 and 90cycle. The simulation results depict the characteristics of the lamp about operating limits during voltage sag by the magnitude and duration of sag in CBEMA curve.
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In this paper, the operational characteristics of SFCL with magnetically coupled two coils were modeled and simulated by PSCAD/EMTDC. The dependence of the line voltage sag on the resistance of superconducting element during the fault period was analyzed. Through the analysis for the winding direction of two coils, the line voltage sag in case of the additive polarity winding was observed to be more improved compared to the case of the subtractive polarity winding.
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The increase of fault current due to large demand has caused the capacity of power machines in power grid to increase. To protect the power system effectively from the large fault current, several superconducting fault current limiters have been proposed. however, in order to apply superconducting fault current limiters into power system, there are many problems such as cost, recovery, AC loss, and cryogenic. In order to solve these problems, hybrid superconducting fault current limiter(HSFCL) was proposed. In this paper, we modeled hybrid superconducting fault current limiter using PSCAD/EMTDC and analyed fault current limiting characteristic and total resistance of hybrid superconducting fault current limiter.
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현재 산업사회의 발달과 더불어 신뢰성 높은 양질의 전기에너지와 운전 및 보수의 간편화, 계통운용의 신뢰성의 확보가 요구되고 있다. 또한
$SF_6$ 을 대체할 친환경적인 절연매체의 개발이 절실히 요구되고 있다. 이에 본 연구는 모의 GIS내 친환경적인 절연재료인 질소($N_2$ )와 산소($O_2$ )의 혼합가스($N_2:O_2=79:21$ ,$N_2:O_2=60:40$ ,$N_2:O_2=40:60$ )의 기본적인 절연특성을 구명함으로서 각종 전력응용 설비의 절연매체로 사용가능함을 구명하고저 한다. -
In this paper, we propose the battery charging device for electric bicycle using photovoltaic power. DC voltage from the solar cells is low, it needs to be step-up by the power conversion device. The power conversion device applied to this paper is phase-shift full-bridge converter. This converter steps-up from 12
${\sim}$ 22[Vdc] to 36[Vdc] for charging the battery of electric bicycle. Phase-shift full-bridge converter(PSFB) can obtain twice as much DC voltage compared with half-bridge converter, thus it has lower current stress less than half-bridge converter. It is simulated and tested the battery charging device using photovoltaic power. -
A design criterion of grounding systems is commonly based on low frequency resistance in Korea. When lightning surges which have high frequency components are injected into the grounding system, the grounding impedance is greatly different from the static grounding resistance. This paper presents the grounding adimittance and phase on the frequency range from 100 [Hz] to 15 [MHz] using water tank simulating the grounding system in different water resistivities. As a result, capacitive effect is dominant over the frequency of 100 [kHz] at the water resistivity of 1,000 [
$\Omega$ m]. On the other hand, the inductive characteristics appear at the low water resistivity. Consequently, dependence of grounding impedances on the frequency of injected current is strongly related to resistivity. -
Because of the high increasing rate of load demand, these days the necessity of deciding what optimum reserve level is appropriate to most stably supply electricity is being emphasized. This research studies the downward tendency of reverve ratio by analyzing the trend of change of the network scale, reserve, and reserve ratio while optimum reserve has been increased as the network system scale grow up. This means, at this moment 6,000MW is optimum level for short term prospect of power supply and demand. And also, it has been analyzed that, as the annual peak load exceeded 50,000MW, confirming the amount of optimum reserve level is more stable than keeping 10 to 12% reserve ratio.
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In this paper, The author present a load current feed-forward compensator by method that improve voltage controller of Step-down Chopper to get stable output voltage to sudden change of load current. To confirm the characteristicsof a presented load current feed -forward compensator compared each transfer function of whole system that load current feed-forward compensator is added with transfer function of whole system that existent voltage controller is included using Mason gains formula in Root locus and Bode diagram. As a result the pole of system is improved, extreme point of the wave and system improves, and size of peak value and phase margin of break frequency in resonance frequency confirmed that is good. Therefore, presented control technique could confirm that reduce influence by perturbation and improves stationary state and dynamic characteristics in output of Step-down Chopper.
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Grounding impedance depends on the frequency of current flowing into a grounding system. Especially, the lightning gives a broad frequency spectrum from low frequency up to 1 MHz. So the grounding impedance related to high frequency current like lightning should be measured with high frequency source. In this paper, we described the grounding impedances of deeply-driven ground rods of 10
${\sim}$ 48 m long with respect to the frequency of injected currents and the feed point. For the experiments, we used the wideband power amplifier which can produce sinusoidal voltages with the frequency ranges of DC${\sim}$ 250 MHz. As a result, the longer the ground rod is, the lower the ground resistance is. However the grounding impedance of deeply-driven ground rod in the range of higher frequency is significantly increased. As a consequence, it is important to evaluate the high frequency performance of grounding systems for lightning protection. -
We improved an efficiency of fiber-optic current transformer by using a metal-coated sensor coil. To reduce the linear birefringence, we used a length of spun fiber as sensor coil, and then used a flint glass fiber coil for comparison. To make the sensor coil in the reflection type, we used different reflection mirrors at the end of the sensor coil, such as a Faraday rotator mirror, a simple mirror, a metal-coated fiber end and a simple fiber end. From the experimental results, the linear error of current measurements were less than
${\sim}$ 0.2 % regardless of the mirror types. The metal-coated sensor was the most cost-effective considering the fabrication cost and the simple structure. -
Capacitors are known as condensers. They play an important in the industrial site because of benefits such as var support, improved voltage control and power factor, increased system capacity, and reduction of system power losses. But capacitors can be seriously affected by bad power quality such as transient and impulsive overvoltage, overload, harmonics. Capacitor standards and application guides are revised or supplemented by speedy technology advancements in the manufacturing of capacitors and in the power electronics. This paper presents various illustrations and comparison for several standards of power system capacitors.
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The purpose of this study is to analyze daylight distribution and light characteristics on the Ma-ji and Roller Shade fabric, and to investigate a possibility of using it as a shading system. Using a 1/2 Mock-up model, daylight distribution is analyzed with the Ma-ji and Sun-ji (Korean traditional paper) which have good efficiency and less glare. Ma-ji has the best daylight distribution, so that daylight experiment is conducted with the Ma-ji and Roller Shade fabric. In current office buildings and apartment houses, daylight characteristics of Korean traditional paper windows could be used as preliminary data to develop a window system which makes better daylight performance.
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Light is the essential element for people to live and do creative activities in architecture. The meaning of light has been changed as time has changed, and today it has more sophisticated roles. The meaning of light was to create static ambience in the past but it can create dynamic ambience currently. The digital light can be a source which creates this dynamic effects such as a human behavior, thought and weather data, and also creates new realm of spatial experience such as the metaphysical. complex, and illusionary space. These characteristics can be revealed from Proun raum spatial characteristics. This study analyzes the characteristics of proun raum, and also compare such characteristics to the variable meanings of digital light.
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Recently, as development of the luminaire industry, many people are interest of the outdoor and indoor lighting environment. Also, as increasing of people activity at night, the role of lighting is more important. In these days, the issue of LEDs lighting environment is using loud colors of LEDs which are the most of primary colors (R, G, B). It is often disliked by same people. Therefore, it is necessary to use of natural color in lighting design using LEDs. The colors of the LEDs are composed of combination of R, G, B diodes. This paper performs to investigate preference of various colors and color patterns of LEDs. The purposes of this study are to suggest standardization and natural colors instead of primary colors using LEDs.
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The daylight responsive dimming system is an energy saving system that automatically controls lighting output of artificial lighting according to available daylight in inside, as well as keeps uniform workplace illuminance. The basic three components of the daylight responsive dimming system consist of a photosensor, a controller and a dimming ballast. This paper is a fundamental study of photosensor modeling for the daylight responsive dimming system. The correlation between photosensor illuminance on the ceiling and workplace illuminance is an important factor to accuracy of system performance, so that the purpose of this study is to improve accuracy for daylight responsive dimming system. This study performs to derive the optimized conditions of photosensor using the RADIANCE.
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Zonal cavity method, which is a kind of the lumen method, is used the calculation of the average illuminance on the workplane in an interior. Important factors of the method are cavity ratio, coefficient of utilization, and light loss factor. A Coefficient of Utilization varies with a kind of luminaires and is affected by surface reflectance of space. For this, the data from Coefficient of Utilization computation were analyzed with the same lumens and different photometry. This paper analyzes the changes of Coefficients of Utilization on the photometry of luminaires and surface reflectance of space.
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Solar Cell을 이용한 15W 휴대용 조명 시스템을 개발하기 위하여, 휴대용에 적합한 solar cell을 선정하고, Solar Cell을 충전하기 위한 태양광 궤적 변화에 대한 Simulation을 행하였으며, 1W 백색 LED 6EA를 사용하여 휴대용 LED Lighting System을 개발하였다. LED Lighting System은 solar cell 충방전 회로 및 LED SMPS 구동회로 설계, 글레어차단을 위한 리플렉터 설계, 방열 설계 및 기구 구조 설계를 통하여 개발되었으며, 직접 시제품을 제작하고 그 성능을 측정하였다.
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본 연구는 국내학술지의 논문 중 고령자의 시지각에 관한 연구의 내용을 분석하여 고령자의 시지각 특성에 맞는 생활환경조성에 필요한 기초자료를 얻기 위하여 수행하였다. DBPLA의 고령자(노인)에 관한 연구 538편과 한국노년학회지에 게재된 663편의 논문, 총 1201편의 학술논문을 연구대상으로 삼아, 고령자의 시지각과 관련된 내용(색체, 조명, 시각, 시지각)을 분석하였다. 그 결과, 고령자와 관련된 연구는 계속 증가하고 있으나 고령자 시지각과 관련된 연구는 매우 부족한 것을 알 수 있었다. 따라서 고령자의 시지각 특성을 파악할 수 있는 다양한 연구의 필요성이 제기되며, 고령자가 자립적인 생활을 하는데 도움을 줄 수 있는 도구의 개발이나 생활환경의 디자인의 필요성을 밝히는 바이다.
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본 연구는 농촌 청소년 공부방을 대상으로 조명환경 실태조사를 실시한 것이다. 그 결과, 공부방의 평균 공간의 크기는 11.42[
$m^2$ ]이며, 주로 광원은 형광등을 사용하였으며 조명사용방법은 전반조명만 이용하는 경우가 73.8[%]이며, 배광방식은 직접조명방식을 주로 사용하고 있었다. 또한 스탠드를 소유하고 있는 가구는 45.7[%]이었으며, 국부조명인 스탠드를 사용하는 비율은 전체 조사대상의 20[%]에 지나지 않아 시작업이 효과적이지 못하였다. 내부공간 조도는 평균 131.82[lx]이며, 책상면 조도는 253.64[lx]로 최저허용조도의 42.3[%]에 해당하는 열악한 실정이었으며, 균제도는 평균 35.61[%]로 나타났다. 또한 사용자의 조명환경에 비해 만족도는 3.93점으로 �F아 조명에 대한 인식이 매우 부족한 것으로 사료된다. -
최근들어 메탈핼라이드램프의 아크튜브에 사용되던 석영관을 내열성 및 내식성이 우수한 alumina ceramic 재질의 아크튜브에 교체한 세라믹 메탈핼라이드램프가 개발되었다. 이러한 세라믹 메탈핼라이드램프는 기존 석영관 메탈핼라이드램프에 비해 고효율, 고연색성 및 장수명 등 우수한 특성을 가지고 있어 램프의 compact화를 통해 150W이하의 옥내 상업용 조명시설에 급속한 보급이 이루어지고 있으며 국내에서도 이러한 세라믹 메탈핼라이드램프 개발을 위한 연구가 진행 중이다. 이에 본 논문에서는 국내 세라믹 메탈핼라이트램프(Ceramic Metal Halide lamp)의 개발에 필요한 국외 선진 제품에 대한 특성 DB구축을 위하여 150W급 세라믹 메탈핼라이드램프의 아크튜브 구조 및 치수를 측정하고 weibull++6을 이용한 성능열화데이터 분석을 통해 세라믹 메탈핼라이드램프의 수명을 예측해 보았다.
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최근 들어 기존 조명기구를 대신하여 LED 조명기구가 크게 각광을 받고 있다. 이는 LED의 장점인 낮은 소비전력과 긴 수명 때문인 것으로 생각된다. 하지만, 빛을 확산시켜야 하는 조명관점에서 본다면 LED 조명기구에도 개선해야 할 부분도 많아지는 것도 사실이다. 본 논문에서는 LED 조명기구에서 빛의 확산을 위해 사용되어지는 고가의 반사판에 대해 실제 개발된 조명기구의 배광곡선 분석과 시뮬레이션을 통해 확산효과를 면밀히 분석함으로써 향후 LED 조명기구의 설계에 있어서 기술 및 경제적 관점에서 도움을 주고자 한다.
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In the gas discharge lamp, starting procedure is composed of several physical discharge phases. The detailed phenomena are different according to lamp characteristics and ballasting method. This paper reviews starting methods in fluorescent lamp, and the starting procedure of HID lamp are investigated based on reviewed various waveforms.
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In a design of ballast for discharge lamp, various kind of protection circuit are essential for safe operation. In this paper, overvoltage and current detection, no-load detection, lamp-fault detection, end of lamp detection for protection are introduced. Individual circuit operation and their function are described with the base that all circuit form is similar with overvoltage protection circuit.
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국내외 터널조명 기법들을 조사, 분석한 것을 바탕으로 향후 터널조명 시스템 적용과 개발 가능성 연구, 분석을 위한 시뮬레이션을 행하였다. 시뮬레이션 프로그램은 Lightscape를 이용하였으며, 터널 내 노면 조도, 조도균제도 그리고 단위면적당 소비전력량에 대하여 비교, 분석하였다.
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본 연구에서는 교통의 안전성, 에너지 절감, 조명시설의 효율적인 유지관리에 주안점을 두고, 국내외 터널조명 관련 기술정보 및 터널조명 기준을 수집하고 분석하여 국제 추세와 국내 실정을 반영한 적절한 터널조명 기준을 제안하였다.
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차량에 탑재하여 60km/h 이상의 고속으로 주행하면서 터널의 노면조도 분포 및 휘도를 측정할 수 있는 하드웨어 측정 장치, 측정용 소프트웨어, 분석용 소프트웨어를 개발하였다. 또한 탈부착이 가능하고 이동의 용이한 차량부착용 장치를 개발하였다.
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In this paper, we report the improved driving methode using planar-gate for field emission light source. Due to the cold cathode in field emission device, it has advantage for driving system in terms of high speed pulse driving with narrow duty ratio. This paper shows that our driving method offers the stable and reliable driving system without rapid electric field variation for field emission light source.
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The field emission lamps have the advantages to their cold cathode-characteristic and the eco-friendly, We realized that the dual emitter system showed very simple structure which gate and cathode electrodes are formed on the same glass surface. In this paper, we reported the properties of dual emitters depended on variation of gate width and spacing for optimum panel structure. In combination of dual emitter structure and bi-polar driving, electron beam spreads more than normal gate structure or diode structure, and emission uniformity increased in dual emitter structure at 5"-diagonal.
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본 연구는 여러 분야에서 언급되어지고 있는 인테리어트렌드를 조사 정리하고, 각 트렌드의 특성을 비교 분석하여 이들을 대표할 수 있는 키워드를 순수, 자연, 혼성의 3개로 추출하였다. 이를 중심으로 2008년 인테리어트렌드를 분류하고, 각 트렌드를 표현하는 색채를 조사하고 재정리하여 3개의 키워드를 대표할 수 있는 색채를 팔레트로 작성하였다. 작성된 색채 팔레트는 거주자들이 개성에 맞는 실내공간을 디자인하는데 효과적으로 활용될 것이며 디자이너와의 상호이해도 높일 수 있을 것이라 기대한다.
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본 논문에서는 골프장 부대시설중 고객 동선에 있는 주차장의 조도를 실측하여 평가하고, 주차장 조도 실측과 야외연습장의 야간조명안을 토대로 Lumen Designer 시뮬레이션 프로그램을 이용하여 한국산업규격 조도기준에 적합한 주차장의 조명 개선방안을 제시하였고 이용 고객의 불편사항을 해소하기 위하여 연습장의 야간조명 설계계획을 수립하여 이를 토대로 시뮬레이션을 통하여 최적의 모델을 도출하였다.
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대학구내 공원시설은 학생들과 시민들의 다양하고 안전하게 사용할 수 있도록 여러 시설을 갖추고 있어야 하며 야간에도 활용 가능케 조명시설을 갖추고 있어야 한다. 본 논문에서는 소공원내의 산책로에서는 볼라드 타입 메탈할라이드 50[W]를 지그재그 배열로 배치하였고, 운동기구에서는 안전성 확보를 위하여 메탈할라이드 400[W]를 7개를 설치하여 조명 계획을 검토하고 설계하였다. 산책로와 운동시설에 대한 시뮬레이션 결과를 활용하여 안정적인 조명모델을 제시 하였다.
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We present the basic theory on phase filtering of hologram to improve the image quality on image reconstruction.
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항로표지용 LED 등명기는 완전방수형 구조이며, 발광형태도 섬광 특성을 가진다. LED 등명기의 색도 및 광도 측정에 있어 섬광형태로 측정하는 것은 그 한계가 있으며, 이에 부동광(연속광)으로 측정이 이루어진다. 이때 중요하게 취급되어져야 할 것이 예열시간이며, 적정한 예열시간 선정에 따라 Field와의 오차를 줄일 수 있다. 본 논문에서는 해상용 LED 등명기의 색도 측정 시에 고려해야 하는 예열 시간을 실험을 통하여 산정해 보았다.
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대표적인 신광으로 일컬어지는 LED는 기존 광원과는 달리 다수의 LED 소자가 모여 하나의 광원을 구성하여 조명기구를 이루는 형태를 가지고 있으며 이에 따라 높은 휘도와 낮은 휘도가 반복되는 발광 형태를 가지게 된다. 이러한 불균일한 휘도를 가지는 광원의 경우 일반적인 균일 휘도 광원에 사용되던 UGR의 평가치가 그대로 적용되는 것은 적절하지 못한 글레어의 평가가 이루어질 수 있다. 따라서 이에 대한 보정이 실행되어야 한다. 본 논문에서는 이러한 불균일한 휘도를 가지는 광원에 대해 UGR 글레어 평가식을 보정하기 위한 실험을 수행할 수 있는 실험실을 구성하고 이에 대한 과정을 서술하였다.
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본 논문에서는 개정된 KS 기준을 만족하면서 새로이 인도 조명기구용 pole을 설치할 필요 없이 기존의 가로등 pole에 바로 적용할 수 있는 높이가 낮은 인도용 조명기구용 반사판의 설계를 실행하고 광학 성능 예측 프로그램을 사용하여 그 성능을 확인하였다. 또한 설계는 신광원에 관심이 집중되고 있는 현재 추세에 맞추어 콤팩트 메탈할라이드 램프를 적용하여 실행하고 조명기구 반사판의 소형화 및 고성능화를 이끌어 낼 수 있도록 하였다.
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친환경적이고 고효율적인 신광원의 개발이 더욱 가속화되면서 개발되고 있는 면광원에 대한 프리즘 설계법의 기초 연구로서, 면광원의 배광을 예측한 라이브러리를 생성한 후 넓은 분포를 갖는 대칭형 배광의 프리즘 조명기구를 설계하고 Lumen micro를 이용한 시뮬레이션을 통해 프리즘 조명기구에 대한 성능을 평가하였다.
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전국 주요 노선의 고속도로 터널도로를 대상으로 터널조명설비가 기준에 적합한지 그 성능을 차량을 이용한 고성능 터널조명 측정시스템으로 측정함으로써 터널조명의 적절성 여부와 터널조명 변화를 파악하고, 그 결과를 바탕으로 우리나라 터널조명의 실태를 비교 분석하였다.
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본 논문에서는 전조등의 밝기변동이 다양한 패턴을 가지고 주기적으로 발생하였을 경우에 대한 운전자의 심리적 반응을 파악하였다. 그 결과 조도변동의 발생빈도가 어떠한 패턴으로 발생하더라도 불쾌감에 미치는 영향은 동일하고 2번 이상 조도변동이 발생하면 불쾌감은 한 번 발생하였을 때 보다 증가하였다.
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자동차에 탑재된 부하 특히, 여름의 에어컨 사용과 같이 큰 부하가 걸릴 경우와 같이 차량내 전기적 부하의 변동이 발생하게 된다. 이러한 부하의 변동이 할로켄 램프를 사용하고 있는 전조등의 밝기를 변화시킨다. 이러한 밝기의 변동은 운전자가 인식할 수 있는 정도가 되며, 그로인해 운전자는 심리적으로 불쾌함을 느낄 것이다. 그러므로 차량 전조등의 밝기변화 패턴에 영향을 미치는 전조등의 전압과 시간을 변수로 하여, 순간적으로 밝기변동이 발생하였을 경우, 연령대별(20/60대)로 운전자가 느끼는 심리적인 반응(불쾌감)이 어떠한 경향을 갖는지를 파악하는 것이 중요하다. 따라서 본 논문에서는 밝기변동 요소가 되는 전압변동 범위
${\Delta}V$ 와 전압변동 시간${\Delta}t$ 로 순간적으로 전조등의 밝기가 변동하였을 때, 이러한 현상이 운전자의 심리적인 반응에 어떠한 영향을 미치는가를 20대와 60대를 대상으로 평가하였다. 이 결과 각각의 전압패턴에 따라 불쾌감이 다르게 나타났으며, 또한 20대와 60대가 전압패턴에 대해 경향을 유사하였으나, 평가치에 대해서는 상당한 차이를 보였다. -
Hold-type display의 동화상 인식 원리를 이용하여 인간의 시각특성을 고려한 동화상 노이즈 컴퓨터 시뮬레이터를 개발하였다. 그리고 이 시뮬레이터를 이용하여 PDP의 동화상 노이즈인 의사윤곽 노이즈의 서브필드 배열과 속도 의존성에 대해 실험하였다. 실험 결과 기존의 서브필드 배열 방식은 의사윤곽 노이즈를 저감시킬 수가 있으나 화상의 이동속도가 빠를수록 노이즈가 증가하는 것을 알 수 있어 근본적인 대책이 될 수 없다는 것을 알았다.
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차량에서 전조등의 밝기 변화가 운전자에게 불쾌감과 스트레스를 제공한다면 운전자 및 보행자의 안전에 위협이 될 수 있을 뿐만 아니라 차량의 전체성능에 의구심을 유발시킬 수 있다. 그러므로 차량 전조등의 밝기변화 패턴에 영향을 미치는 전조등의 전압과 시간을 변수로 하여, 순간적으로 밝기변동이 발생하였을 경우, 연령대별(20/60대)로 운전자가 느끼는 심리적인 반응(불쾌감)이 어떠한 경향을 갖는지를 파악하는 것이 중요하다. 따라서 본 논문에서는 운전자가 순응하고 있는 전조등에 의한 노면상황을 모의하고 전조등의 전압이 13.6[V]에서 12[V]까지 변동하는 빔 패턴을 화면으로 구성하여 전조등의 순간적인 밝기변동을 모의하였다.
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본 논문에서는 LED의 고출력화가 이루어지면서 많이 사용되고 있는 LED MR 타입과 PAR 타입의 램프 배광을 설계하였다. 1W와 5W급의 High power LED를 적용하였고, 1개의 LED가 사용된 빔각 30도의 MR16 램프부터 9개의 LED가 사용된 빔각 60도의 PAR30 램프까지 총 6가지 배광을 구현하고 최대광도로 각각의 성능을 평가하였다. 빔 각을 구현하고 집광시키기 위하여 LED dome 측면부에 소형의 반사판을 설계하였다.
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도로조명에서 시인성과 글레어는 안전과 직결된 매우 중요한 사항이다. 본 논문에서는 낮은 위치에 설치되는 라인조명 방식과 가로등 조명 방식의 시인성과 글레어 영향을 비교평가하기 위한 시험실을 구성하였다. 이 후 피험자들을 선발하여 예비시험을 거친 후 본 시험을 실시할 예정이다.
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This paper gives a comparative analysis on lifetime of the fluorescent induction lamp. We have treasured and analysed optical characteristics of circular type fluorescent induction lamps, which has A and B types, to estimate lifetime. In the result of analysis on lifetime,
$B_{10}$ lifetime of A and B type lamps are 466 hours and 1,595 hours, respectively. -
본 논문에서는 LED(light emitting diode)조명과 CNT(carbon nano-tube)조명에 대한 전기적인 특성과 광학적 특성을 측정하여 비교하고 고찰하였다. 특히 IES format 파일을 사용하여 각각의 조명등기구에 대한 LID(luminous intensity distribution) 분석과 조도 시뮬레이션을 수행하여 최대 및 최소, 그리고 평균조도 등을 분석하였다. 향후 LED 및 CNT 신광원은 면조명으로의 관련 기술기준 및 규격의 작성시 참고자료로 활용될 것으로 판단된다.
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본 연구에서는 실리케이트 적색 형광체의 신뢰성을 향상시키기 위하여
$SiO_2$ 박막을 졸-겔(sol-gel) 방법으로 코팅하였으며, 봉지재의 종류에 따른 코팅된 형광체의 신뢰성 변화를 조사하였다. 졸-겔 코팅 후 형광체 표면을 관찰한 결과 졸-겔 코팅이 잘 이루어 졌음을 알 수 있었으며, 4회 코팅 후 박막의 두께는 약 150nm였다. 코팅하지 않은 형광체의 경우 봉지재에 따른 차이는 있었지만 500시간 경과 후 효율 감소율은 30% 이상이었으며 코팅 한 형광체의 경우는 에폭시, JCR6175가 10${\sim}$ 25%, EG6301은 10% 이내의 효율 감소율을 보였다. 한편 색좌표 경우 에폭시 봉지재가 약 0.02의 변화를 EG6301 봉지재의 경우 0.01 이내의 변화를 보였다. -
In this paper, the recent technologies of a guardlamp are surveyed and the research on the actual condition of the management and maintenance is carried out. In addition, this paper intends to arouse people's attention to the electrical disasters caused by neglecting the installation, operation, management and maintenance of the guardlamp. In the process of the research, a field survey, a meeting of interested persons and manufacturers were performed and their opinions were reflected.
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The Power LED is more much than 1W and appliable to lights that is different from signal LED. In this paper we investigated types of tests in reliability assessment standards on Power LED. we make comparison of that military standards, JEITA(Japan Electronics and Information Technology Industries Association) and JEDEC(Joint Electron Device Engineering Council) with RS(reliability standard). Reliability tests should be considered that informations can be obtained from requirements of a real system Therefore, The paper aided companies to criteria for reliability tests by themselves.
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본 연구에서는 빛을 확산시키기 위하여 LED(light emitting diode) 봉지층내에 마이크로 스피어를 형성하였다. 마이크로 스피어는 극성이 다른 이 종의 봉지재(실리콘, 에폭시)를 혼합하여 제조하였으며, 최적 첨가비율은 0.6wt% 이내였다. 광학현미경을 이용하여 측정한 결과, 마이크로 스피어의 직경은
$4{\mu}m$ 내외였으며, 마이크로 스피어는 서로 들러붙거나 침전하지 않았다. LED의 효율은 봉지재의 첨가비율이 증가할수록 감소하였으며, 0.6wt% 첨가하였을 때 약 10% 이내의 효율 감소를 보였다. 지향각은 봉지재 첨가비율을 0${\sim}$ 0.6wt%로 변화시키면 50도에서 110도까지 증가하였다. -
BLUs(Backlight Units) are major component in LCD(Liquid Crystal Display) industry which occupies 90% or more of worldwide FPD(Flat Panel Display) market. And BLU market is expected to be expanded continuously according to the trend of miniaturization, slimness, low power consumption and low weight. The larger the BLU market scale, the more important standardization of performance evaluation techniques to clearly prescribe the product specification. This document is a generic specification of measurement methods of LED BLU for LCDs. It defines general procedures for quality assessment and gives general rules for measuring methods of LED BLU for LCDs.
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본 논문은 알칼리토금속계인 마그네슘 등의 수화 반응에 수반되는 반응열과 전기화학적 작용을 이용하여 버너와 같은 화기를 이용하지 않고 야외에서 생수 등을 간접가열 하여 커피, 컵라면, 분유, 피자등의 음식을 가열 할 수 있는 발열제품을 개발하는 데이터를 얻었다. 마그네슘과 금속계 화합물을 혼합하여 tea bag에 넣어 셀 형태로 만들어 발열효과를 높이기 위해 특수시험관의 재질 및 두께의존성, 발열제 양과 혼합물질에 따른 온도특성 등을 확인하였다. 발열제에서 발생되는 열의 효율적인 전달과 포장 재질의 선정 및 휴대의 간편성 등을 고려하여 타당성을 검증하였다.
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The permanent magnet BLDC motors are increasingly being used in high performance applications due to the high torque density and simplicity in their control. In this paper, the control system of the BLDC motor is developed which can be used for the micro motor handpiece, and position sensorless control is realized using back EMF measurement scheme, The validity and practical applications of the developed slotless BLDC motor and drive system are verified through the experimental results.
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This paper gives a basic data of the breakdown characteristics of l-Air(Imitation Air,
$N_2:O_2=79:21$ ) and$SF_6$ gas based on temperature variations in experimental GIS model by applying negative DC voltage. The breakdown charcteristics were compared with gas pressures and each gas already entered in GIS model. The characteristics of l-Air and$SF_6$ were different in specific temperature range that$SF_6$ gas was being liquefied. The breakdown voltages of$SF_6$ were more higher than l-Air except for 4[atm] at$-10{\sim}0[^{\circ}C]$ . -
This paper gives a basic data of the breakdown characteristics of Dry-Air and air based on their dew point and humidity variations in experimental GIS model by applying AC voltage. The breakdown voltage of Dry-Air was increased as gap length had been increased. The characteristics of Dry-air which had low dew point were higher. In the case of air, the breakdown voltage curves were like Dry-Air' s. But the curves were slightly folded up and down because of impurities.
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Recently, the concern of PV systems has increased because of an environmental problem and limitation of fossil fuel. In this paper, we assume and simulate the cases that the voltage of distribution system exceed the bound of voltage regulation because of the connected PV system. Also, we compare the typical method, LDC(Line Drop Compensator), with the suggested method and verify propriety of suggested method.
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This paper gives a description of the mode'ling and control of a single phase PWM(Pulse Width Modulation) converter for HEMU-400X(High-speed Electric Multiple Unit - 400 km/h experiment). The converter is part of a Auxiliary power unit supplied by the 25[kV], 60[Hz] overhead line. A model of the converter in a synchronously rotating reference frame of coordinates is used to develop a new type of control. The control system has separate controllers for the active and reactive current, permitting the free choice of the power factor. This paper proposes a new control method of PWM converter for Auxiliary power unit.
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In Factory Automation(FA) used by Programmable Logic Controller(PLC), Ladder Diagram(LD) is the most widely utilized and plays an important role in industrial control system. But recently, the study about Sequential Function Chart(SFC) is performed actively. When we program by SFC, generally, we design one routine from start to end. This method is difficult to design block control system, and we often make mistakes. In this paper, we propose the method that we design block control system and we analysis the difference of the method used this paper from conventional method.
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In this paper, the PSCAD/EMTDC modeling of JeJu AC power system with wind farms will be discussed. And the modelling of the synchronous generator, exciter, governor will also be defined in the JeJu power system by using the PSCAD/EMTDC. At the same time the fault analysis and the power flow analysis in JeJu AC power system are presented to demonstrate the JeJu AC power system can perfectly simulate the real JeJu power system function. Through the simulation using PSCAD/EMTDC we have gained the same results compared with the results accomplished by the PSS/E. so the validity of the modelling for the JeJu power system by using PSCAD/EMTDC is confirmed.
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In this paper, the battery charging device using DMFC(Direct Methanol Fuel Cell) for electric bicycle is proposed. In the proposed system, phase-shift full-bridge converter is used as a battery charger by boosting the 12V DMFC output voltage up to 36V. By using the phase-shift technique, the ringing of the transformer is reduced and the efficiency of the converter can be improved. The operation modes of proposed phase-shift full-bridge converter is analyzed and verified by the simulation and the experimental results.
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This paper describes the ground surface potential profiles near the object to be grounded. The hemisphere water tank was used to simulate the. scale model. As a result, the ground surface potential near the ground electrode was considerably raised. In particular the ground surface potential at the just upper part of ground rod was higher than other part. The ground surface potential was lowered with increasing the buried depth of ground rod.
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입력신호인 도로표면의 화상 데이터는 낮 시간대의 아스팔트 포장 도로면을 촬영하여 도로표면 상태의 화상을 만들었고, 편광 및 웨이블릿 변화(Wavelet transform)으로 도로 표면을 5가지의 상태(건조, 습윤, 수막, 적설, 동결)로 인식할 수 있는 분류기준절차를 연구하였다. 표면 화상 인식 과정은 편광계수에 의한 젖은 땅으로 분류한 후, 다음으로 젖은 땅을 제외한 나머지는 웨이블릿 패킷 변환을 통해 시간-주파수 분석을 하였다. 또한 영상 템플릿을 이용하여 마른 땅과 빙판의 표준적인 주파수 특성을 분석하여, 마른 땅과 빙판을 구분하였다. 도로표면영상에서 마른 부분과 젖은 부분을 구분한 결과를 정리하였다.
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This paper is simulated overall composition of permanent magnet synchronous motor using Simulink in Matlab. In general permanent magnet synchronous motor drive system, SVPWM method is usually adopted. The simulation results in this paper show the speed and torque characteristics of PMSM with motor drive which is modulated by SVPWM. Through this simulation, it can be possible to verify the component which affects the torque and speed control causing the SVPWM.
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정보화 사회의 급격한 변화로 첨단 기기들은 우리의 생활에 없어서는 안 될 존재가 되었지만 이는 각종 노이즈 및 서지에 노출되어 있다. 또한 기상이변으로 낙뢰에 대한 피해가 점점 증가하고 있어 효율성이 높은 대책이 요구된다. 따라서 KS 9609는 단순 보호각에 의한 건축물 보호로 폐지되고 WTO의 TBT협약에 의한 기술 부합화 차원에서 KS C IEC 61024로 제정되었다. 그리고 미흡한 부분을 보완하고 강화시킨 62305라는 새로운 피뢰설비 규격을 받아들였다. 그러나 이것 역시 실제 적용시 여러가지 문제점이 드러났다. 본 논문에서는 KS C IEC 62305의 문제점을 파악하고 이를 해결하기 위한 방안에 대하여 설명하고자 한다.
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In this work, the development of the diagnosis algorithm is carried out for identifying health and faulted conditions in three-phase induction motors. The algorithm consists of feature calculation, feature extraction, and feature classification procedures in sequence. Signals for this algorithm are acquired by current and flux sensors simultaneously, the latter is to measure the change of magnetic flux at the air-gap, This work proposes the efficient diagnosis method for induction motors by developing the powerful algorithm. The calculated features show a good linearity according to faults severities. Moreover. the final results show a good classification rate on motor conditions.
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Inundation of substation and ground power equipment breaks out every summer season in low-lying downtown and low-lying shore by localized heavy rain, typhoon and tidal wave. In case inundation excluding the exchanging cost of equipment, it occurs a great economic and social loss owing to recovery time and events of electric shock occur by inundation electrical equipment(Pad-mounted Transformer and Switch). In case of installing the power equipment at flood danger territory, we are necessary to the product development, the product is that water does not come in the inside the power equipment. Product of pressure maintaining are established on the basic frame and sensor operates at the flooding occurrence and is maintained a shutting tightly structure and it is a method. The product which is produced the reliability of the product it confirmed a flooding yes or no from the condition which puts in the water tank and it verified. We estimate that loss cost which is caused by with flooding and the power failure will be diminished if it is addition to advances the reliability evaluation and a security of the flood protection product.
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Even though many modular converters have several internal protection circuit blocks for various abnormal operation conditions, there are many failure cases on modular converters at real applications. In this paper, the control strategy for failure protection of converters with internal 'In-Hibit' function is investigated. As an example, for the MDl modular converters the in-hibit function application is realized and the test results shows that adopting in-hibit function while converter switching reduces the voltage and current stress. And the reduction of switching stress on converter will decrease failure rate on converters.
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This paper describes the electrical characteristics of the ZnO surge arrester according to the variation of surrounding conditions. To investigate the characteristics of degraded ZnO surge arrester, 8/20 [
${\mu$ s], 2.5 [kA] impulse currents were applied to the ZnO surge arrester to be test. To present the effect of the surrounding con야tions, the leakage currents of ZnO surge arrester were measured to the surrounding temperature and wet conditions. As a result, the increase of ambient temperature causes the increase of resistive leakage current of ZnO surge arrester. Also, in the wet test, the outside leakage current through the ZnO surge arrester housing is much larger than the intrinsic leakage current. -
Contract power conversion factor which is applied to estimate contract power of general customers IS an important standard to caculate transformer capacity. This paper shows a reasonable contract power conversion factor, that was made by the systematic and statistical way considering actual conditions, such as investigated contract power and peak power for the last 5 years of each customer for 132 office building customers as to AMR system. In this dissertation, it is necessary to analyze the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimun and thus it was carried the linear and nonlinear regression analysis. Therefore, this paper compared characteristics for a contract power conversion factor which is applied to calculate contract power with characteristics for a regression model for customers which maximum utilization factor of transformer is more than 60%.
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This paper presents the behaviors of transient and conventional grounding impedances of a deep-driven ground rods associated with the injection point of lightning impulse currents. The transient impedance of deep-driven ground rods under lightning impulse currents were higher than the static ground resistance. The transient grounding impedances strongly depend on the injection point and size of grounding electrodes and the rising time of impulse current. Reduction of ground system inductance is an important factor to lightning surge protection.
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This paper presents the experimental results on breakdown characteristics in
$N_2$ gas under non-uniform electric fields caused by both the positive and negative lightning impulse voltages.$N_2$ gas have an advantage of eco-friendly and cost reduction, and safety aspects. In order to analyze the impulse pre-breakdown processes in$N_2$ gas, we carried out measurements and observations of the impulse breakdown voltages, pre-breakdown current and luminous signals. They were measured by a voltage divider, a shunt and a photo-multiplier tube, respectively. Additionally, the characteristics of discharge channels were observed by high speed cameras. The breakdown voltages in the positive polarity was lower than those in the negative polarity. -
This paper presents characteristics of soil ionization when high currents such as lightning and switching surge currents are injected into a grounding rod. Soil ionization phenomena are investigated by using both voltage and current signals recorded by oscilloscope. As a result, a critical electric field intensity(
$E_C$ ) for ionization is decreased with reduction of grain size. The pre-ionization resistance($R_1$ ) and post-ionization resistance($R_2$ ) at the sand with fine grain size are getting lower with increasing current magnitude. Finally, the time to ionization($t_1$ ) and ionization current peak($t_2$ ) of fine grain size are significantly shorter than those of medium grain size. -
In this paper, we investigated electric safety manager's PL recognition and accident occurrence of electric power facilities(power cable, transformer, circuit breaker) in electric installation for private use. The target of questionnaire survey is 450 electric installations for private use, 154 responded the questionnaire among these and it occupied 35.8%. Most of receiving voltage were 22.900kV. The questionnaire survey says that 58% of electric safety manager knew well about PL contents and 42% of them did not recognize about PL contents, About the PL application of electrical facility accidents, 82.4% of them must applied PL law, 5.8% of them did not need the PL law. Reason of PL application occupied 64% for stability of electrical facility and product, 19% for prevention of same accident. The accident of transformer occupied most and the power cable accident were much next. The questionnaire survey results, electric safety managers are interested in PL content. thev expected necessity of PL application about electrical accident strongly.
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This paper presents the error factors of Fall-of-potential test method used in measurements of the grounding-system impedance. This test methods inherently can introduce two possible errors in the measurements of grounding-system impedance: (1) ground mutual resistance due to current flow through ground from the ground electrode to the current probe, (2) ac mutual coupling between the current test lead and the potential test lead. The errors of ground mutual resistances and ac mutual coupling are expressed by the equation in calculating grounding impedance. These equations were calculated by Matlab that is commercial tool using mathematical calculation. The results of calculation were applied to correct grounding impedance.
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This paper presents the battery management system(BMS) for the optimum conditions of the lead-Acid battery in UPS. The proposed system controls the over and under currents of battery for protecting and it was applied algorithm for optimum conditions to estimate the State Of Charge(SOC) and State Of Health(SOH) in charge or discharge mode. It approved the performance and the algorithm for the estimation of SOH, through the experiments which using the charge and discharge tester and the field tests.
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This paper presents the battery management system(BMS) for the optimum conditions of the lead-Acid battery in UPS. The proposed system controls the over and under currents of battery for protecting and it was applied algorithm for optimum conditions to estimate the State Of Charge(SOC) in charge or discharge mode. It approved the performance and the algorithm for the estimation of SOC, through the experiments which using the charge and discharge tester and the field tests.
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This paper presents a new conceptual electromagnetic induction eddy current-based stainless steel plate spiral type heater for heat exchanger or dual packs Heater in hot water system boiler steamer and super heated steamer, which is more suitable and acceptable for new generation consumer power applications. In addition, an active clamped quasi resonant PWM high frequency inverter using trench gate IGBTs power module can operate under a principle of zero voltage soft commutation with PWM is developed and demonstrated fora high efficient induction heated hot water system and boiler in the consumer power applications This consumer induction heater power appliance using active clamp soft switching PWM high-frequency inverter is evaluated and discussed on the basis of the simulation and experimental results.
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전기에 의한 화재 발생시 재래시장은 소방안전관리체계나 일관된 지휘체계를 갖추고 있지 않아 화재발생시 적절한 대응을 하지 못해 많은 재산상 피해를 보게 된다. 전기에 의한 화재를 예방하기 위해서는 전기설비의 열화나 고장에 대한 절연저항 측정 또는 누설전류를 측정하는 등의 대책이 있으나 전기설비 열화나 고장은 비가시적이고 비노출식이므로 이를 상시 검출하고 감시할 수 있는 시스템 개발을 필요로 하게 된다. 따라서 본 논문에서는 전기화재에 취약한 재래시장용 전기안전 감시시스템 개발을 위한 준비단계로 먼저 고압이나 저압을 수전 받고 있는 국내 재래시장 17개소에서 수배전반, 분전반 등에 사용하는 차단기들의 종류와 용량 및 상가 분전반에 사용하는 차단기의 종류와 용량, 분기 회로수 등에 대한 조사 분석을 통해 재래시장용 전기안전 감시시스템의 기초자료로 활용하고자 한다.
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The matrix-type superconducting fault current limiter (SFCL) using YBCO thin film consists of the trigger and current-limiting parts. We fabricated the matrix-type SFCL with the integrated current limiting modules. we carried out the experiment of matrix-type SFCL with the integrated current limiting modules connected in series or parallel. We saw current characteristics due to ratio of change the shunt resistance and turns. We confirmed that the difference of critical current between superconducting units was decreased by increment of current flowing into the reactor which applied the magnetic field into the superconducting units..
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With the improvement of industrial society, the high quality electrical energy, simplification of operation and maintenance, ensuring reliability are being required Also we request urgently change a
$SF_6$ for an environment friendly gas insulation material. In this paper the experiments of breakdown characteristics by pressure and gap change of Imitation-Air in model GIS(Gas Insulated Switchgear) were described. Also assess of breakdown characteristics about Imitation-Air and$SF_6$ . It is considered in this paper that the results are fundamental data for electric insulation design of Distribution Power Facilities which will be studied and developed in the future. -
본 논문에서는 이중 구조의 공동에서 작은 공동 전원단 내부에 존재하는 전자파원으로부터 방사되는 전자파를 내부 전원단의 개구를 지나 외부 공동의 개구를 통해 방사될 때, 내부 전원단의 위치와 외부 공동의 개구 위치 변화에 따른 방사 전자파의 크기를 FDTD법으로 검토하고 있다. 외부 공동 개구의 크기는 최대 방사 전자파의 주파수를 결정하며 내부 전원단의 위치를 조절하면 방사되는 전자파의 크기를 제어할 수 있음을 이론해석으로 통하여 확인하고 있다.
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건축전기설비기술사는 건축전력시설물을 취급하는 전문가로서 이론과 실무경험이 동시에 요구된다. 따라서 이론과 실무를 갖춘 기술사를 많이 배출하기 위해서는 기출문제 분석이 필요하며 이를 바탕으로 수험생이 효과적으로 준비할 수 있는 방안을 마련할 필요가 있다. 본 연구에서는 과년도와 최근 4년간의 출제경향을 분석하여 대학 교과과정과 기술사 시험과의 연관성을 조사하였다. 출제경향과 대학 교과과정간의 차이를 보완하기 위한 학습방법을 제안하였고, 또한 전력기술인의 재교육을 담당하는 기관의 실무능력 향상을 위한 교육과정을 소개하였다.
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The electrical accidents result from insulation blackdown due to over voltage and overheating due to the excess of allowable current, deterioration of insulation performance due to the passage of time, and so on. In this paper, the insulating characteristics of phenolic resin using insulating materials for low voltage were analyzed and the tracking test was performed according to IEC Publ. 112.
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This paper is proposed that the photovoltaic/fuel cell hybrid generation system for the stand-alone system. In case of the photovoltaic generation system, it depends on the weather condition, irradiation and so on... On the contrary, fuel cell has not this limitation. It can be interactive generation system between photovoltaic and fuel cell. This paper simulated stand-alone co-generation system based on the control of DC link. Moreover, 1[kw] BLDC motor system with speed and hysteresis current controller is used for the proposed system.
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In this paper a high efficiency soft switching boost converter is proposed for photovoltaic system. Using some resonant components, the circuit can be achieved the soft switching capability. Each of the switches in the proposed circuit performs ZV (Zero Voltage) or ZC (Zero Current) switching. Thus, the high efficiency characteristic can also be obtained, and then the size of the total system can be reduced. The operational modes of the verifying the effectiveness of the proposed circuit. As a matter of course, we will present the simulation results in this paper.
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This paper deals with assessment of electrical safety for grounding system of buildings by investigation on the spot at construction site. The investigation was carried out for grounding method, grounding type, shape of grounding electrode, grounding for lightning protection system, continuity of steelwork in reinforced concrete structure and so on. The investigation on the spot was performed by researcher, engineer with over fifteen years of industry experience all over the country. As a result of investigation on the spot to 13 buildings, common grounding method was dominant. A new grounding system based on international standards includes unity grounding system, structure grounding utilizing steel reinforced concrete, equipotential bonding. use of surge protective device.
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This paper introduce the model of remote monitoring system that combine information technology in electrical safety checks that has been done by professional staff. And for general use, electrical safety Value-Added Service using remote check data were presented. In the near future, If demand and interests of Value-Added Service will be increased, this will be a electrical safety Value-Added Service as an important role in the blind spot of country electricity disaster.
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이번 사례는 154kV 변전소 OO송전선로(T/L)인 출입철탑(철주 포함) 설계 시 설치장소의 협소한 문제점을 해결하기 위한 대책을 수립하고 이에 대하여 시공과정에서 발생한 문제점 과 이를 개선한 사례를 분석하였다. 표준형 철탑으로 설계 시 인 출입에 따른 전로의 전기적인 이격거리를 확보하기가 어려우며, 이를 개선하기 위해 특수형상의 철탑 및 기초형식의 인입방안 설계에 대한 개선대책과 현장 개선 사례 분석을 통하여 향후 인입 전선로 설계검토에 참고자료가 될 것으로 사료된다.
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사업용전기설비에 대한 사용전검사 수행 중 전기설비기술기준 및 판단기준에 부합되지 않거나 공사계획신고의 기술시방서 및 설계도서 등의 내용과 일치 않는 부분에 대한 시정 조치한 개선사례를 분석하고 이를 전파하여 전기재해 예방에 도움을 주고자 하며, 향후에도 중요 개선사례들을 지속적으로 발굴하여 현장 전력기술 능력 향상을 위하여 노력해 나아가고자 한다.
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Recently, ozone is utilized in various fields and its needs are expanding. In this paper, glass and ceramic plate tyre ozonizer have been fabricated to investigate discharge parameter(input power, flow rate of supplied gas, electrode form, etc.) effect to discharge. And the conditions of discharge parameter have been investigated for optimum ozone generation. Ozone concentration is continuously increased with increasing input power for same discharge space, and ozone yield is also increased until maximum point after that it is saturated. Ozone concentration is inversely proportional to flow rate of supplied gas but ozone generation and ozone vield characteristics are improved.
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We developed a fiber-optic Bragg grating sensor system using a SOA fiber laser for over heat detection in power systems. To compensate the nonlinear wavelength tuning of the fiber laser, we used fixed passband wavelengths from Fabry-Perot ITU filter as reference wavelengths. Gaussian line-fitting algorithm was also used to reduce the FBG peak detection error. Compared with a highest-peak-detection and a polynomial-fitting method, the proposed Gaussian fitting algorithm could drastically reduce the measurement errors. Also the SOA fiber laser made it possible to enhance the signal-to-noise-ratio even with several kilometers of lead fiber.
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This study investigated the influence of electric facilities damaged by dusts and domestic regulations. Its contents included the around circumstance of electric facilities, regulations concerned with the dust, the actual conditions at the scene, the characteristics of dusts and so on. At the set-up the electric facilities, the around circumstances are bad in summer that highly temperature and many moisture. Besides, elements that are judged the corrosive vapours of the large quantity are detected at the sampled dusts. As the results, if dusts covered with electric facilities, It will be a cause for the electric accidents. From the analyzed data of the actual conditions and the sampled dusts, electric facilities maintenance for the viewpoint of the safety can be possible.
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This paper is proposed a high performance speed control of the synchronous reluctance motor through the artificial intelligent SV-PWM. SV-PWM is controlled using fuzzy control that is artificial intelligent control. SV-PWM can be maximum used maximum dc link voltage and is excellent control method due to characteristic to reducing harmonic more than others. Fuzzy control has a advantage which can be robustly controlled. Simulation results are presented to show the validity of the proposed algorithm
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Interior permanent magnet synchronous motor(IPMSM) has become a popular choice in electric vehicle applications, due to their excellent power to weight ratio. In order to maximize the efficiency in such applications, this paper proposes the FNN(Fuzzy Neural-Network)-Pl controller. The controllable electrical loss which consists of the copper loss and the iron loss can be minimized by the error back propagation algorithm(EBPA). This paper considers the parameter variation about the motor operation. The operating characteristics controlled by efficiency optimization control are examined in detail.
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The paper proposes a novel control algorithm for tracking maximum power of PV generation system. The maximum power of PV array is determinated by a insolation and temperature. Prior considered the term in PV generation system is how maximum power point is accurately tracked. The paper proposes a FNN(Fuzzy Neural-Network) control algorithm so as to accurately track those maximum power points. The proposed control algorithm comprises the antecedence part of fuzzy rule and clustering method, multi-layer neural network in the consequent part. FNN has the advantages which are depicted both high performance and robustness in Fuzzy control and high adaptive control in Neural Network. Specially, it can show the outstanding control performance for parameter variations appling to non-linear character of PV array. In paper, the tracking speed and the accuracy prove the validity through comparing a proposed algorithm with a conventional one.
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In this paper proposes a novel tracking algorithm regarding the power loss when operating a tracking system for a rapidly changing insolation to improve the power of PV tracking system. In case of tracking an azimuth and altitude of the sun in realtime, therefore, the actual PV power is less increasing than the power of tracking system fixed a specific position. To reduce the power loss, this paper proposes a nonel control algorithm of the tracking system. The paper is analyzed efficiency about conventional PV tracking method, comparing proposed algorithm with high performance method. We show propriety of proposed algorithm by means of the demonstrable study.
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This paper presents a maximum power point tracking(MPPT) of photovoltaic system with duty ratio of DC-DC converter considered load. A variation of solar irradiation is most important factor in the MPPT of PV system That is nonlinear, aperiodic and complicated. NN was widely used due to easily solving a complex math problem. The paper consists of solar radiation source, DC-DC converter, DC motor and load(cf, pump). NN algorithm apply to DC-DC converter through an adaptive control of neural network, calculates converter-duty ratio using an adaptive control of NN. The results of an adaptive control of NN compared with the results of converter-duty ratio which are calculated mathematical modeling and evaluate the proposed algorithm. The experimental data show that an adequacy of the algorithm was established through the compared data.
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In this paper a novel tracking system is described, regarding the influence of shadow between array, aimed at improving the efficiency of PV tracking system. The loss by influence of those shadow can be compensated for by means of control algorithm of the tracking device. The paper suggests a method controlling an altitude for length which is received the shadow influence of PV array. By using an azimuth of current solar position and the length between arrays, the controller of tracking device is able to calculate the length between actual arrays and make a comparison of the shadow length at a specific time with the length between arrays. In the paper, we develop the control algorithm able to minimize the loss caused by the influence of shadow on the PV tracking system, and compared this with conventional output system. The controller has been tested in the laboratory with proposed algorithm and shows excellent performance
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This paper presents an innovative prototype of a new conceptual electromagnetic induction-based fluid beating appliance using voltage-fed type scries capacitor-compensated load resonant high-frequency IGBT inverter with a phase-shifted PWM and a power factor correction schemes. Its operating characteristics in steady-state are illustrated including unique features and evaluated on the basis of its computer simulation and experimental results of 10kw breadboard appliance for hot water producer and superheated steamer. The promising cost effective inverter-fed boiler appliances for electromagnetic induction-heated type fluid-heating in the pipeline systems are proposed for induction-heated boiler, super heat steamer, high temperature water producer, hot gas producer and metal catalyst heating for exhaust gas cleaning in engine, which are more suitable and acceptable for industrial, chemical, and consumer energy utilization for household and business from a practical point of view.
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This paper presents a novel prototype of ZCS-PFM high frequency series resonant Inverter using IGBT power module for electromagnetic induction eddy current-heated roller in copy and printing machines. The operating principle and unique features of this voltage source half bridge inverter with two additional soft commutation inductor snubber are presented Including the transformer modeling of induction heated rolling drum. This soft switching inverter can achieve stable zero current soft commutation under a discontinuous and continuous resonant load current for a widely specified power regulation processing. The experimental results and computer-aided analysis of this inverter are discussed from a practical point of view.
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In this paper, We have designed and manufactured a photochemical reaction lamp type ozonizer system which was applied to keep quality of herb medicines during storage. We used photochemical reaction lamp in a storage system, and investigated the sterilization characteristic. Also, we made research an ingredient and quality characteristic of herb medicines according to ozone storage.
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철도차량용 냉방기는 각 차종별로 기능은 대동소이하나 용량과 부품이 상이하고 제작년도별로 부품 제작사 등이 서로 달라 호환성이 적어 유지보수에 애로가 많고 검수시간과 과다소요 등 비용이 과다 지출되고 있는 실정이다. 이에 고장처치를 위해 냉방기를 차종별로 일목요연하게 정리하고 형식 규격 용량 등을 파악, 그 현황을 도시하여 가동현황과 검수공정 등을 고찰하며 체계적이고 효율적인 유지보수 방안을 도출하고 응급복구에 대응할 수 있는 고장 처치 요령을 제시함으로써 검수 질 향상을 통해 냉방기의 수명을 연장시키고 궁극적으로 여객수입증대를 기함과 동시에 고객서비스를 향상시키고자 한다.
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본 논문에서는 원자력 발전소의 SG세관 검사를 위한 배열와전류프로브의 와전류탐상 특성을 해석하였다. 신호해석을 위해 원자력발전소 SG 세관의 내부 및 외부결함을 모델링하였으며, 결함의 깊이는 세관 두께의 40[%]로 하였다. 해석방법은 3차원 유한요소법을 이용하여 전자기 수치 해석을 수행하였다. 두 종류 결함의 수치해석 비교 결과 내부결함의 신호가 외부결함 신호에 비해 크게 발생되는 것을 확인할 수 있었으며, 또한 획득한 신호를 ASME 표준 시험편을 이용한 배열와전류 프로브의 와전류탐상 실험신호와 비교하였다. 본 논문의 결과는 원전설비검사를 위한 배열와전류프로브 신호의 특성해석에 도움이 될 것으로 사료된다.
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최근 국내 IT 산업의 발달에 따른 디지털화에 따라서 대기전력에 의해서 소비되는 전력소모량은 일반 가정용 전원을 기준으로 할 때 전체 사용량의 11%에 육박하는 수준까지 나타나고 있으며, 이는 다른 선진국에 비해서도 상당히 높은 수준으로 미국의 5% 수준의 2배가 넘는 수치이다. 전기, 전자제품의 디지털화 의 추세는 일반가구 및 산업시설에 공급되는 공급전압에 비해서 상당히 낮은 전압으로 제품이 동작하게 되며, 이러한 전압변환은 제품에 내장된 변압기에 의해서 수행되는데, 변압기는 전기, 전자제품이 구동하지 않는 경우에도 일차측에 인가된 전압에 의해서 발생되는 대기전력 소비량에 의해서 일정 크기의 전력소모가 지속적으로 이루어지고 있다. 본 연구에서는 대기전력에 대해서 가전제품의 대기상태를 유지하기 위한 상태에서 소모되는 전력량 및 변압기의 1차측에서 유도되나 2차측에서 전력에너지로 변화되지 못하고 소실되는 손실을 모두 포함하는 것으로 정의를 내리고, 해당 적용 제품의 비구동상태에서 독립된 전원으로 구동되어 변압기의 1차 측을 완전히 개방하여 1차 측 전압인가에서 발생되는 손실까지 모두 줄일 수 있는 회로에 대한 기술적인 구성과 적용가능성에 대하여 연구하였다.
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It has been known that the value of soil resistance drops when a high impulse curennt is injected into a grounding electrode. In this paper, impulse generator is used to investigate the dry soil and wet soil characteristics in cylinderical test cell. The impulse resistances and breakdown characteristics were discussed based on its voltage and current traces. As a result, sand resistances are decreased with increasing the applied currents. It was thought that a decrease in resistance of dry sand with increasing current is due to both thermal and ionization processes. On the other hand, in case there is no water presence in the soil, the reduction in resistance as the currents are of dry sand increased is mainly due to the ionization process.
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The 7-phase BLDC motor is possible for higher efficiency per the unit area, high power and high speed due to the increasing number of phase. Also, it can be looking forward to reduce the current ripple at a point of commutation by the increasing number of phase. Thus, a study for applications of servo system, medical and military instruments is progressing about the BLDC motor is manufactured with multi-phase, currently. This paper is used the fuzzy logic control method for speed control of 7-phase BLDC motor and this is compared with the conventional PI controller using by simulation and experimental results for verification validity of the fuzzy logic controller in this system. The 7-phase BLDC motor and controller are modeled by PSIM6.0 software of PowerSim co. in simulation and we are experimented by the test board that is composed with TMS320VC33-150 DSP controller of Texas Instruments co. and FLEX EPF6016TC144-3 of ALTERA co.
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There are increased interests in using new regeneration energy due to the effect of the latest rising oil price. On this account, various practical applications using small stand-alone PV generation system are being made. In this paper, with intent to change mercury lamp using for existing garden lamp with high flux LED, we have considered load characteristic using high flux LED modules applied to PV system. It is simulated with PSIM and made experiment set with a 75[W] solar cell module, DC-DC converter, controller and battery.
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It is difficult to find for analysis solution of the synchronous generator exciter system. Recently, it had good performence UPS converter system using CRA method. The single converter of synchronous generator excitor system under considerations : (i) the overall system shall keep very low AC-voltage tracking error as well as no phase delay over different load condition, and (ii) the digital controller shall be employed at a fixed sampling. It is shown that the synchronous exciter system can be achieved by the proposed controller using Characteristic Ratio Assignment.