• 전력전자학회논문지
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• 제21권5호
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• pp.453-456
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• 2016

The major causes of electrical fire in low-voltage distribution lines are classified into short-circuit fault, overload fault, electric leakage, and electric contact failure. The special principal factor of the fire is electric arc or spark accompanied with such electric faults. This paper studies the development of an electric fire prevention system with detection and alarm of that in case of parallel arc fault occurrence in low-voltage distribution lines. The proposed system is designed on algorithm sensing the instantaneous voltage drop of line voltage at arc fault occurrence. The proposed detector has characteristics of high-speed operation responsibility and superior system reliability from composition using a large number of semiconductor devices. A new sensing control method that shows the detection of parallel arc fault is sensed to ripple voltage drop through a diode bridge full-wave rectifier at electrical accident occurrence. Some experimental tests of the proposed system also confirm the practicality and validity of the analytical results.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 F
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• pp.2075-2077
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• 1997

An electronic starter using MOSFET is developed to take advantage of ideal preheating and starting features which can extend the lifetime of fluorescent lamps. The preheating curcuit of the developed electronic starter is consisted of three parts - a full wave rectifier curcuit, an FET switching curcuit, and a timer curcuit for the gate switching. The curcuit allows sufficient preheating current flow before the starting to protect lamp filaments, nevertheless it shortens the Preheating time and enables a single pulse ignition at the peak level of the line voltage. Experimental results show that fluorescent lamps of 20-40W range can be initiated within rather short time of $1{\sim}1.5sec$ with preheating current of 0.6A. The electronic starter withstands more than 70.000 cycles switchings without noticeable blackening due to anode spot. These features provide Proper evidences for the advantage of direct replacement with the new starter.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전기물성,응용부문
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• pp.65-67
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• 2003

This paper describes a design of power supply for electrodeless lamp system to be easy to control electric power widely keeping the high power factor. Proposed system is composed of power factor correction(PFC) circuit, half bridge(HB) inverter, high voltage transformer, full wave rectifier to supply dc number kV's magnetron(MGT) anode voltage in the second of high voltage transformer and magnetron. It was confirmed that the proposed circuits can correct the 99.8[%] power factor and control input power of the magnetron up to 33.3[%] linearly by adjusting of pulse frequency of the inverter through the experiment.

• 조명전기설비학회논문지
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• 제26권9호
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• pp.47-56
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• 2012

This research is to develop satiable battery charger with a variety of capacity and voltage specifications of battery. For this, voltage or current were controlled through buck converter which is DC voltage that already received three-phase at primary side and passed bridge rectifier diode. And, it was comprised of full-bridge converter and HFTR for insulation and a square wave AC. The transformer primary side was comprised in series to divide certain charging current and the secondly side was comprised of 6 fixed transformers so that they can generate certain amount of power and various output voltage through relay parallel compound 6 DC Link outputs. To confirm such structure's verification and validity, simulation with PSIM was conducted, and validity of proposed variable charger system was verified through 3kW stack production.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 C
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• pp.1631-1633
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• 2001

In manufacturing processes, various and suitable pulse shapes are required for the purpose of material processing and the pulseshape is regarded as a dominant factor due to the specific property of processing materials. Therefore, in this study, a variable pulse width, high duty cycle Pulse Forming Network(PFN) is constructed by time sequently. The power supply for this experiment consists of three switching circuits. The PFN elements operate at low voltage and drive the primary of HV leakage transformer. The secondary of the transformer has a full-wave rectifier, which passes the pulse energy to the load in a continuous sequence of properly phased and nested increments. We investigated laser pulse width as various delay time among three switching circuit. As a result, we tan obtain various laser pulse width from about 4ms to 10ms. The maximum laser pulse width obtained at this experiment was about 10ms at delay time of 4ms among each switching circuit.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2005년도 춘계종합학술대회
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• pp.273-276
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• 2005

This paper presents an electronic ballast using a step down converter, a low frequency inverter for high pressure discharge lamp. The proposed ballast is composed of a full-wave rectifier, a step down converter operated as a current source with power regulation and a low frequency inverter with ignition circuit. The ignition circuit generates high voltage pulse of 1${\sim}$2[kV] peak, 130[Hz]. Moreover, it is able to reignite at regular intervals by protective circuit. As experimental results on the test, lamp voltage, current and consumption power are measured 132.5[V], 7.6[A] and 1,005[W], respectively. It was confirmed that the designed ballast operate the lamp with a constant power.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2011년도 추계학술대회
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• pp.392-395
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• 2011

본 논문에서는 압전 소자를 이용한 진동에너지 하베스팅 회로를 설계하였다. 압전소자의 전력-전압 특성을 이용해 최대 전력을 부하로 전달하기 위한 MPPT(maximum power point tracking control) 제어 기능을 추가하였다. MPPT 회로는 전파 정류회로의 개방회로 전압을 주기적으로 샘플링하여 최대 가용전력이 생성되는 지점을 추적하고 이를 부하로 전달한다. 진동에너지 하베스팅 회로는 $0.18{\mu}m$ CMOS 공정으로 설계하였다. 최대 전력 효율은 91%이고, pad를 제외한 칩 면적은 $1,100{\mu}m{\times}730{\mu}m$이다.

• 한국태양에너지학회 논문집
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• 제39권1호
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• pp.51-58
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• 2019

This paper deals with the operation of a hybrid power generation system made with photovoltaic cells and piezoelectric materials. The system can produce power from the wind as well as from the sun subject to their availability. Irrespective of the largeness of their power production, the power developed by both generators (i.e., phtovoltaic cells and piezoelectric cells) were combined and stored before it was applied to a load. Especially, the AC power (current) developed from each piezoelectric generator was converted by a full wave bridge rectifier and then combined prior to its storage in a capacitor. It was observed that the system can produce a maximum output power of 6.49 mW at loading resistance of $100{\Omega}$.

• 대한전자공학회논문지SD
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• 제38권3호
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• pp.211-219
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• 2001

본 논문에서는 RFID를 위한 읽기 전용 CMOS 트랜스폰더를 one-chip으로 설계하였다. 리더에서 공급되는 자기장으로부터 트랜스폰더 칩의 전원을 공급하기 위한 전파정류기를 NMOS 트랜지스터를 사용하여 설계하였으며, 데이터 저장 소자로는 64비트의 ROM을 사용하였다. 메모리에 저장되어 있는 ID 코드는 Manchester 코딩되어 front-end 임피던스 변조 방식으로 리더에 전송된다. 임피던스 변조를 위한 감폭회로로는 리더와 트랜스폰더 사이의 거리가 변해도 일정한 감폭율을 갖는 새로운 감폭회로를 사용하였다. 설계된 회로는 0.65㎛ 2-poly, 2-metal CMOS 공정을 사용하여 IC로 제작되었다. 칩 면적은 0.9㎜×0.4㎜이다. 측정 결과 설계된 트랜스폰더 IC는 인식거리 내에서 약 20∼25%의 일정한 감폭율을 보이며, 125㎑의 RF에 대해 3.9kbps의 데이터 전송속도를 보인다. 트랜스폰더 칩의 전력소모는 읽기 모드시 약 100㎼이다. 인식거리는 약 7㎝이다.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2015년도 추계학술대회
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• pp.477-480
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• 2015

본 논문에서는 MPPT(Maximum Power Point Tracking) 제어 기능을 갖는 저전압 진동에너지 하베스팅 회로를 제안한다. 제안된 회로는 Bulk-driven technique을 적용하여 0.8V의 낮은 전압에서도 동작 가능하다. 압전소자의 출력단에 연결된 전파정류기의 개방회로 전압을 MPPT 제어회로를 통해 주기적으로 샘플링하고, 최대 가용전력 점의 전압을 부하에 전달한다. 제안된 회로는 0.35um CMOS 공정으로 설계되었으며, 패드를 포함한 칩 면적은 $1.33mm{\times}1.31mm$이다. 모의실험결과 설계된 회로의 최대 전력효율은 85.49%이다.