• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권8호
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• pp.551-556
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• 2000

A zero-voltage-switching(ZVS) programmable power supply employing the ZVS active clamp forward converter is suggested. Through the analysis on operation region of the supply, the constant power region and the maximum current limit region are clearly identified. Furthermore, the duty ratio range corresponding to the variation range of the output voltages and the control scheme at the minimum duty ration region are presented. Finally, in order to vefity the validity of the operation for the proposed power supply, experimental evaluation results obtained on an 1kW prototype power supply for the 198~242VAC input voltage range(220VAC$\pm$10%), the 0~25V output voltage range, and the 100kHz switching frequency are presented.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 하계종합학술대회 논문집(2)
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• pp.45-48
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• 2001

An programmable current-mode folding and interpolation analog to digital converter (ADC) with programmable interpolator is proposed in this paper. A programmable interpolator is employed not only to vary the resolution of data converter, but also to decrease a power dissipation within the ADC. Because of varying the number of interpolation circuits, resolution is vary from 6 to 10bit. The designed ADC fabricated by a 0.6${\mu}{\textrm}{m}$ n-well CMOS double metal/single poly process. The experimental result shows the power dissipation from 26 to 87mW with a power supply of 3.3V.

• Journal of Advanced Marine Engineering and Technology
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• 제36권8호
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• pp.1117-1122
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• 2012

연료전지를 선박에 적용하는 연구를 위해서는 연료전지 특성을 고려한 전력 시스템 설계 및 부하 제어에 대한 연구가 필요하다. 하지만 연료전지를 직접 실험하기 위해서는 여러 보조기기들과 복잡한 제어 기술이 필요하다. 이러한 이유로 연료전지 시뮬레이터가 필요하며, 이를 위한 연구가 활발히 진행중이다. 본 논문에서는 자동차, 소형 선박 등에 적용되고 있는 PEMFC에 관하여 LabVIEW를 기반으로 시뮬레이션 하였다. 또한 이러한 시뮬레이션 데이터를 바탕으로 프로그램이 가능한 전력공급장치를 이용하여 시뮬레이터를 제작하여 연료전지의 특성을 구현하였다. 이를 통해 연료전지의 분극화 곡선과 변수에 따른 I-V특성을 확인할 수 있었다.

• Journal of Power Electronics
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• 제10권3호
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• pp.228-234
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• 2010

This paper investigates the conducted-noise characteristics of a digitally-controlled randomly-switched dc-dc converter. In order to investigate the effect of the suggested digital controller on the conducted-noise characteristics of a dc-dc converter, three factors have been studied: the field-programmable gate array (FPGA) clock speed, the randomization ratio percentage, and the effect of using a closed loop feedback controller. A field-programmable gate array is much more flexible than analog control circuits, has a lower cost, and can be used for power supply applications. A novel FPGA-based implementation has been suggested for obtaining the experimental validations and realizing the studied concepts. Furthermore, the experimental results have been discussed and design guidelines have been included.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2006년도 전기학술대회논문집
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• pp.249-250
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• 2006

In this paper, hardware design and implementation of digital controller for the High Precision Digital Power Supply (HPDPS) based on Digital Signal Processor (DSP) and Field Programmable Gate Array (FPGA) is presented. Developed digital controller is composed of high resolution Digital Pulse Width Modulation (DPWM) and high resolution analog to digital converter circuit with anti-aliasing filter. And Digital Signal Processor (DSP) has the capability of a few micro-second calculation time for one feedback loop. 32-bit DSP and DPWM with 150[ps] step resolution is used to implement the HPDPS. Also 18-bit 2 mega sample per second ADC board is adopted for the developed digital controller. Also, hardware structure of the developed digital controller and experimental results of the first prototype board for HPDPS is described.

• Journal of Advanced Marine Engineering and Technology
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• 제38권8호
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• pp.1000-1003
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• 2014

There are 70 vertical and 70 horizontal correctors for Pohang Light Source. Until mid of 2000, power supplies for these correctors were based on 1990's technology, so the global orbit feedback system was not possible with poor 12 bit resolution. A new task force team was assembled to develop new power supplies with BESSY type DAC cards. After the project, two vertical correctors in each lattice were connected with new power supplies, and the global orbit feedback was available within the accuracy of 5 microns. However, this replacement was not enough to satisfy the beam stability requirement of 2 microns for PLS. We have launched another power supply design based on all digital technology. This attempt was completed within a year, and 80 units were assembled in house. Currently, the global orbit feedback system is running successfully with new digital power supplies and the compensation of chamber motion due to the thermal load by using digital displacement transducers attached on each BPMs.

• Journal of Power Electronics
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• 제7권4호
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• pp.336-342
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• 2007

This paper presents the development of a fuel cell dynamic simulator using a programmable DC power supply and LabVIEW graphical user interface. The developed simulator closely describes the static and dynamic characteristics of an actual proton exchange membrance fuel cell (PEMFC). The experimental results are provided to verify the operation of the simulator. The developed simulator can be used as a convenient and economic alternative to an actual fuel cell for developing and testing a fuel cell power conditioning system.

• KIEE International Transactions on Power Engineering
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• 제5A권3호
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• pp.214-220
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• 2005

In order to improve energy efficiency and solve power disturbances, power components measurement for both the supply and demand side of a power system must be implemented before appropriate action on the power problems can be taken. This paper presents a DSP (Digital Signal Processor)-based multi-channel (voltage 8-channel and current 10-channel) power measurement system that can simultaneously measure and analyze power components for both supply and demand. Voltage 8-channel and current 10-channel measurement is made through voltage and current sensors connected to the developed system, and power components such as reactive power, power factor and harmonics are calculated and measured by the DSP. The measured data are stored in a personal computer (PC) and a commercial program is then used for measurement data analysis and display. After voltage and current measurement accuracy revision using YOKOGAWA 2558, the developed system was tested using a programmable ac power source. The test results showed the accuracy of the developed system to be about 0.3 percent. Also, a simultaneous measurement field test of the developed system was implemented by application to the supply and demand side of the three-phase power system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(2)
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• pp.208-211
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• 2000

This paper describes the design of a CMOS frequency synthesizer using programmable frequency divider with novel architecture. A novel architecture of programmable divider can be producted all of integer-N and fabricated by 0.65$\mu\textrm{m}$ 2-poly, 2-metal CMOS technology. Frequency synthesizer is simulated by 0.25$\mu\textrm{m}$ 2-poly, 5-metal CMOS technology. This circuit has settling time of 1.5${\mu}\textrm{s}$ and power consumption of 70㎽. Operating frequency of the frequency synthesizer is 820MHz∼l㎓ with a 2.5V supply voltage.

• Journal of Power Electronics
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• 제16권1호
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• pp.190-204
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• 2016

An active front end (AFE) is required for a three-phase induction motor (IM) fed by a voltage source inverter (VSI), because of the increasing need to derive quality current from the utility end without sacrificing the power factor (PF). This study investigates a proportional-plus-integral (PI) controller based AFE topology that uses a super-lift converter (SLC). The significance of the proposed SLC, which converts rectified AC supply to geometrically proceed ripple-free DC supply, is explained. Variations in several power quality parameters in the intended IM drive for 0% and 100% loading conditions are demonstrated. A simulation is conducted by using MATLAB/Simulink software, and a prototype is built with a field programmable gate array (FPGA) Spartan-6 processor. Simulation results are correlated with the experimental results obtained from a 0.5 HP IM drive prototype with speed feedback and a voltage/frequency (V/f) control strategy. The proposed AFE topology using SLC is suitable for three-phase IM drives, considering the supply end PF, the DC-link voltage and current, the total harmonic distortion (THD) in supply current, and the speed response of IM.