비상조명등 및 비상구유도등 예비전원용 커패시턴스의 완전방전에 관한 연구

전중함 한국화재소방학회 2016 한국화재소방학회 학술대회 논문집 Vol.2016 No.추계

위상제어 직류전원의 실험적 고찰

전중함 명지대학교 교지편집위원회 1978 明大 Vol.9 No.-

단위 역율 정류에 관한 연구

전중함 대구보건대학 1996 대구보건대학 論文集 Vol.16 No.-

3상 1개의 스윗치의 소프터 스윗칭 방식의 PWM 콘버터가 이논문에서 제안된다. 불연속 모드의 콘버터는 복잡한 제어회로를 없애고, 부품수를 줄이고, 그리고, 필터의 유도성 부품의 크기를 줄인다. 불연속 모드컨버터에서 스윗칭소자의 턴온은 ZCS(Zero Current Switching) 이 된다. 한편으로, 소자는 유도전류의 최대값에서 턴오프 해야 한다. 이전류의 최대값에서 제로전압이 되도록 동작 하므로서 로스레스 스너버에의한 스윗치소자로 대치하게 된다. PWM 컨버터에 제안된 소프터 스윗치의 동작을 디지털 시물레이셴과 실험결과를 비교한다. 또한, 절연 출력을 가지는 벅 부스터 PWM컨버터에 한 개의 3상 소프터스윗치를 제안해 보기도 한다. Recently AC-DC converters have been used widely for condenser input type rectifier which has a simple structure. However, this circuit have a low power factor be-cause input current flows while the input source voltage greater than the capacitor voltage. To improve that, it has been studied about AC-DC converter using rectifier and chopper. 0he methode of chopper control has merit in which waveform and power factor is improved. The kinds of chopper control are a methode controlling inducter current continuously and discontinuously. The former controls input waveform with a PWM in the sinusoidal wave as voltage and current found and its control is very complecated. The latter relatively is simple for controlling chopper and results in the effect of power factor improvement as controlling source current. and it can operate three phase high power factor converter by a switch but this kind of method can be possibly zero current switching as turned on of the control device and can be high turn off loss as turned off it being operated in the maxi-mum current. This control method is called HARD SWITCHING. This paper propose soft switching type three phase high power factor converter by switching loss of the turn off is decreased with using lossless subber condenser. Proposed circuit decreased switching loss operating can be possibly ZCS, ZVS with using the partial resonant switching topology which is resonant circuit just as switching and have a merit which brings efficiency increasing as it makes to the source a regeneration of accumulated energy in subber condenser. Therefore it can increase the total efficiency of the circuit. Relatively simple circuit composition and soft switching three phase converter which has low loss came true.

단상 다중 AC-DC Converter

전중함 대구보건대학 1999 대구보건대학 論文集 Vol.19 No.-

Single-phase multi-level AC-DC converter that is composed of diode bridge and switch is proposed. The number of the supply current level is depending on the individual current level of the converter. A converter circuit, the number of the level is equal to 2^(M+1)-1, where M is the number of Switching Converter. The proposed circuit has converter with 31 current levels. When the number of current level is increased, smoother sinusoidal waveform can be obtained directly and it is possible to control the supply current almost continuously from zero to maximum without generating high voltage step changes as pulse with modulation technology. The technique illustrates its validity and effectiveness through the PSIM.

비상전원용 가역전력변환기의 연구

전중함 대구보건대학 2005 대구보건대학 論文集 Vol.25 No.-

Recent, Emergency Power Source littler by little Very important. Now, The converter is composed of a series connection of individual single phase converters. The number of the input current levels depends on the number of the individual inverters in series and their input current level. If the number of current levels is increased, smoother sinusoidal waveform can be obtained directly. In this paper discusses single-phase AC-DC converter that driven by binary combination at different transformer winding ratio by BCD code level. Also DC-AC Inverter. It has a advantage that constructs a control system simply and obtain load current of good quality without filter circuit and free from noise or isolation for lower switching frequency. This has merit that can do high power capacity. In this research, study on current type converter and inverter circuit that consist for possibility of AC-DC/DC-AC multi-level converter.

멜티레벨 컨버터의 Feedback 제어에 대한 연구

전중함 대구보건대학 2003 대구보건대학 論文集 Vol.23 No.-

The converter is composed of a series connection of individual single phase converters. The number of the input current levels depends on the number of the individual inverters in series and their input current level. In this converter circuit, the number of the levels is equal to 2m+1, 2^((m+1))-1 or 3^(m) where m is the number of switching-legs used. If the number of current levels is increased, smoother sinusoidal waveform can be obtained directly. This paper discusses sing1e-phase AC-DC converter that driven by binary combination at different transformer winding ratio. It has a advantage that constructs a control system simply and obtain load current of good quality without filter circuit and free from noise or isolation for lower switching frequency. Also, this has merit that can do high power capacity. In this research, study on feedback circuit that consist for load stability of AC-DC multi-level converter.1

삼상 Boost Up 컨버터에 적용된 무손실 서너버 콘덴서의 에너지회생에 대한 연구

전중함 대구보건대학 1998 대구보건대학 論文集 Vol.18 No.-

This paper proposed a partial resonant three-phase PWM AC-DC boost converter using a lossless snubber of high power factor. The proposed converter has a merit of simple controlled circuit because the input current control discontinuously. And it is improve to input power factor that the snubber capacitor's energy regenerate to the AC source side. Specially using the discontinue current mode in the reactor. Furthermore it is sure that the soft-switching method using lossless snubber. This topology is reduced a current / voltage stresses of resonant devices in addition to a partial resonant strategy. The result of simulations of the proposed topology included in this paper.

비상조명등 및 피난구유도등 전원설계에 관한 연구

전중함 한국화재소방학회 2016 한국화재소방학회 학술대회 논문집 Vol.2016 No.춘계

자동화재탐지설비 P형수신기의 지구회로에 관한 연구

전중함 대구보건전문대학 2007 대구보건대학 論文集 Vol.27 No.-

Recent, Fire system little by little important. Still more fire alarm system is very important. Fire alarm system have to fire detector, signal receiver and alarm. Therefore this fire alarm keep to human life from a fire structure. After fire fighting. Fire alarm system divide about R type receiver and P type receiver. Now many selection P type receiver install in large structure. This paper first study local circuit in P type receiver of fire alarm system. And define this local circuit condition for interlock other fire protect equipment of structure. Next, turn this data to good account proposal of circuit design in P type receiver fire alarm system.

변압기 2차 전류 제어형 Multy-level Converter

전중함 대구보건대학 2000 대구보건대학 論文集 Vol.20 No.-

The standards of power correction and reducing high harmonics in power converter system was recently published in the U.S. and Europe. And regulations of the Total Harmonics Distortion(THD) on industry and electronic machines are increasing. Therefore, the studies of reducing input power harmonics and power factor correction in the power converter system have been conducted actively in order to solve these problems. With regard to this, the third phase, AC/DC Converter of PWM Type, has been researched in the world. However, PWM Control type has fundamental problems such as a lot of power loss which is occurred when it controls the main circuit and difficulty in making it as a high power converter. Therefore, it is needed to draft the plan on low pass filter or active filter as their needs. This paper proposed multi-level PWM Control converter which controls input current by combining buck converters together to improve input current characteristic, and confirmed its validity throughout simulation and experiment. This method, which is multiplying and duplicating output of converter of equal capacity, is able to control unit power factor of input current, reduce the problem caused by high frequency switching, and apply to high power converter because filter is not necessary.