• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.248-251
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• 2006

최근 사무용 빌딩에서 비선형 부하에 기인한 전압 및 전류파형의 왜곡 및 고조파로 인해 배선용 및 누전차단기 불필요 동작 또는 오동작이 발생하고 그로 인한 피해사례가 보고되고 있으나 어느 정도의 고조파양과 차수가 어떻게 영향을 미치는지 알 수 없다. 따라서 수용가에서 발생하는 고조파 양과 차수의 측정과 분석을 통한 배선용 및 누전차단기 동작특성의 평가가 필요하다. 본 논문에서는 고조파로 인해 배선용 및 누전차단기 불필요 동작이 발생하는 사무용 빌딩에서의 전압 및 전류 고조파의 크기, 전압 및 전류 파고율 등을 측정 및 분석하여 향후 고조파에 의한 배선용 및 누전차단기 동작특성 평가 연구에 활용할 수 있도록 하였다.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.1
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• pp.37-44
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• 2003

This paper proposes on-line based a deterioration diagnosis pole transformers using various sensors such as thermistor, current transformer and potential transformer. We measured load current and temperature to diagnose pole transformer using R/F( radio frequency ) wireless data communication module. We represent the graphs of their feature. The result of this paper shows that the proposed device car be used as deterioration diagnosis device of pole transformers.

• Proceedings of the KIPE Conference
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• 2008.10a
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• pp.88-90
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• 2008

본 논문에서는 유도전동기에서 발생되는 고장들 중에서 고정자 권선 단락 고장 특성 해석과 고장 판별에 대한 방법을 제시한다. 고정자 권선 단락을 판별하기 위해서 단락상태의 고정자를 모델링하여 3상 전류 불평형과 공극자속밀도에 대한 유한요소해석을 수행하였다. 유한요소해석으로 얻어진 결과의 타당성을 입증하기 위해 실험을 통하여 전류와 공극자속에 대한 유기기전력 측정값을 비교하였다. 공극자속의 유기기전력을 측정하기 위해 고정자 슬롯에 자속센서를 취부하였다. 고정자 권선 단락 시 3상 전류는 불평형을 이루고 공극자속밀도가 감소되어 유도전동기의 고정자 고장을 판별하는 기초자료가 된다.

• Proceedings of the KIPE Conference
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• 2006.06a
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• pp.216-218
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• 2006

본 논문에서는 연료전지용 듀얼 부스트 컨버터의 전압제어루프의 피드백 루프에 디지털 필터를 도입하여 부하에 의해 발생하는 출력전압의 저고조파 리플성분을 제거한 측정값을 사용함으로써 입력전류의 저고조파 리플을 제거하고, 전류제어루프에 predictive deadbeat 제어기법을 적용하여 제어주기와 제어알고리듬 계산에 의한 시간적 지연에 의해 발생되는 동적응답특성의 저하를 최소화한다. 센서를 사용하는 대신 연료전지 스택에 공급되는 수소와 공기의 압력과 스택의 출력전류에 결정되는 연료전지의 전압-전류 특성곡선을 이용하여 부스터 컨버터의 입력전압을 계산하고 전류를 제어함으로써 연료전지 시스템의 성능을 최적화한다.

• Journal of the Korean Institute of Telematics and Electronics
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• v.22 no.2
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• pp.75-81
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• 1985

In low current injection level, the output signal of the 12 L is damaged and disturbed by the external loads (capacitance, resistance, current). Thus the uncertainty of the circuit can be increased .'This paper makes an analysis on the influences which the external loads have upon the 12 L-inverter function. It compares and analyzes the calculated result and measured result about the variation of rise time and fall time by means of computer simula-tions and experiments.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.12 no.1
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• pp.117-125
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• 1998

In this paper, in order to develop the three phase GTO CSI of high efficiency 1M drive with low loss commutation and snubber energy, we studied the energy recovery circuit to recover stored energy in clamping capacitor and DC link inductor(VCC-l and VCC-2), and snubber capacitor(VCC-3). By using an induction motor as the load of inverter, experimental results show that dissipated DC power is decreased and capacitor voltage Vc is effectively suppressed by VCC-2 and VCC-3 system, and the validity of VCC-3 system with low loss commutation and snubber energy is proofed.roofed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.689-692
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• 2015

That induced voltage by an electrified railway line is related with the position of telecommunication line between traction power feeding systems is practically varified by measurements in the real field. This experimented fact is conformed with the calculated simulation provided by the ITU-T Directives concerning the protection of telecommunication lines against harmful effects from electric power and electrified railway lines. Therefore it is needed to consider at what position a telecommunication line is parallelized with power feeding line of traction system when an induction phenomenon is evaluated or measurement is carried out besides the length of parallelization and the separate distance between power line and telecommunication line.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.44 no.1
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• pp.16-21
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• 2007

A Dual-Path Voltage Multiplier for passive RFID Tags was proposed and fabricated by using a 0.25um CMOS process with additional steps for schottky diodes. The proposed circuit needs only 4 additional diodes, and the area increment compared to conventional one is negligible in multi-stage voltage multipliers. The simulation and measurement results show that the output power capability of proposed multiplier are about two times larger than the conventional half-wave multiplier.

• Fire Science and Engineering
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• v.34 no.3
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• pp.67-75
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• 2020

In this study, the risk of heat generation due to normal and overload currents that vary with the abnormal loosening angle of wire-connecting bolts were identified. The risks were analyzed based on the thermal characteristics to minimize the carbonization accidents of terminal blocks inside distribution panels typically used in industrial sites. We applied a method for measuring the heating temperature and temperature variations in the terminal blocks in real-time by installing a resistance temperature detector sensor board in the terminal block. The experimental results showed that the terminal block model with a low-rated current exhibited a higher heating temperature, thus, confirming the need to select the terminal block capacity based on load currents. Additionally, the higher the rated current of the terminal block with a high-rated current and the higher the degree of loosening, the faster the carbonization point. Such heating temperature monitoring enabled real-time thermal temperature measurement and a step-by-step risk level setting through thermal analysis. The results of the measurement and analysis of carbonization risks can provide a theoretical basis for further research regarding the risk of fire due to carbonization. Furthermore, the deterioration measurement method using the temperature sensor board developed in this study is widely applicable to prevent fires caused by poor electrical contact as well as risk-level management.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5838-5842
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• 2011

The study mainly aims to explore how deterioration of motor control center, namely MCC, and vibration put impact on temperature of bus bar as well as temperature change of bolt-nut joint. The motor control center consists of three internal parts (i.e. R, S, T) which are for motor operation of high capacity. Two dimensional mechanism for measuring temperature was designed and manufactured with infrared temperature sensor. Installing it in inner motor control center enabled researcher to monitor temperature of bus bar as well as amount of change of current regularly. Temperature change of bus bar according to load was primarily examined based on a bolted joint in the experiment. It was clearly verified that temperature change of bus bar was proportional to current consumption. Therefore, installing non-contact two dimensional mechanism for measuring temperature in motor control center would be expected to prevent temperature rise owing to overload current and power outage as well as fire accident which can be triggered by poor electrical contact.