• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.1 no.3
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• pp.119-125
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• 2008

This work involves analyzing partial discharge (PD), which has estimated the detected signal accumulation based on Labview, and analyzing by Fuzzy algorithm. In algorithm, we developed system configuration that detected accumulating PD signal. With practical PD logic implementation of theoretical detected system and hardware implementation, the device for 50kV setup has generated and then has applied with 15k~17kV with 1:1 time probe. Our new class of PD detected algorithm has also compared with PRPDA or Fuzzy algorithm, which has diagnose more conveniently by adding numerical values.

• Journal of Power Electronics
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• v.10 no.4
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• pp.365-373
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• 2010

This paper proposes a hybrid single carrier sinusoidal modulation suitable for multiphase multilevel inverters. Multiphase multilevel inverters are controlled by hybrid modulation to provide multiphase variable voltage and a variable frequency supply. The proposed modulation combines the benefits of fundamental frequency modulation and single carrier sinusoidal modulation (SC-SPWM) strategies. The main characteristics of hybrid modulation are a reduction in switching losses and improved harmonic performance. The proposed algorithm can be applied to cascaded multilevel inverter topologies. It has low computational complexity and it is suitable for hardware implementations. SC-SPWM and its base modulation design are implemented on a TMS320F2407 digital signal processor (DSP). A Complex Programmable Logic Device realizes the hybrid PWM algorithm and it is integrated with a DSP processor for hybrid SC-SPWM generation. The feasibility of this hybrid modulation is verified by spectral analysis, power loss analysis, simulation and experimental results.

• Journal of Power Electronics
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• v.10 no.6
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• pp.686-693
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• 2010

In this paper, a fault diagnosis method based on fuzzy logic for the three-parallel power converter in a wind turbine system is presented. The method can not only detect both open and short faults but can also identify faulty switching devices without additional voltage sensors or an analysis modeling of the system. The location of a faulty switch can be indicated by six-patterns of a stator current vector and the fault switching device detection is achieved by analyzing the current vector. A fault tolerant algorithm is also presented to maintain proper performance under faulty conditions. The reliability of the proposed fault detection technique has been proven by simulations and experiments with a 10kW simulator.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.910-915
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• 2003

This paper describes the design of a 2-phase stepping motor driver using CPLD(Complex Programmable Logic Device). The driver IC such as L297 (SGS-Thomson Microelectronics), which is mostly used has some problems in PWM control because of the switching noise of power MOSFETs. It causes current ripple and acoustic noise. To improve theses characteristics, we proposed a new current control method that the output PWM frequency is almost constant using a digital filter. Also we proposed constant current method for 1-2 phase(half step) excitation. The proposed method is implemented with CPLD(Xilinx, XC9572-PC44). Experimental results show the effectiveness of the proposed method.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1756-1757
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• 2007

어느 정도 규모를 가진 실험 설비를 자동화하기 위해서 분산 I/O를 지원해 주는 자동화 컨트롤러를 사용하는 것이 편리하며 이러한 용도로 PLC(Programmable Logic Controller), PAC(Programmable Automation Controller) 등을 사용하고 있다. 하지만 기능적으로 필요로 하는 I/O 이외에 전원장치, 백프레임, 그리고 메인콘트롤러 등의 항목이 추가된다. 이러한 제한은 필요로 하는 자동화 대상인 설비의 I/O의 접점수가 많지 않지만 이들을 분산하여 설치될 필요가 있을 경우 전체 시스템을 자동화 하는데 소요되는 비용을 필요 이상으로 높이게 된다. 본 연구는 현재 한국원자력연구원에서 시험 운전 중인 TS-NBI 장치의 자동화에 이용할 목적으로 자동화 대상 설비의 I/O 접점수가 많지 않지만 분산 I/O로 구성하여야 하는 경우에 적용할 해결책을 찾기 위해서 수행 하였다.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.1445-1446
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• 2007

In this paper, we have studied for analysis of the partial discharge(PD) signal in power transmission line. The PD signal has estimated as detected signal accumulation of a PRPDA method by using Labview, and analyzed with neural-fuzzy algorithm. With practical PD logic implementation of theoretical detected system and hardware implementation, the device for Hipotronics Company's 22.9kV or 154kV setup have generated and then have applied with 18kV,20kV with 1:1 time probe. It's also used the LDPE 0.27mmt (scratch error 0.05mmt) to sample for making PD. Our new class of PD detected algorithm have also compared with previous PRPDA or Neural Fuzzy algorithm, which has diagnose more conveniently by adding numerical values.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.78-80
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• 2007

According to the development of VLSI integration technology and getting bigger the circuit size, it is a significant problem to verify systemized circuit. The faster and more accurate verification has very significant meaning in the field of electronic industry because it can yield the product comparably faster and reduce the trial and errors. In spite of the presence of various kind of Integrated Circuits it's not always easy to get the right part. Besides, it is hard to find a vendor for a small quantity consumers like who develop prototype applications. In this study, we've tried to get the logical signals from the PC based device we've developed that correspondents with the real ICs. It can emulate decoder ICs, multiplexers, demultiplexers and basic logic gates.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2000.08a
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• pp.65-68
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• 2000

In this paper, as a compatible software radio transmission system, Digital-Radio conversion system which can directly change the digital signal generated by the logic circuit into radio signal is proposed. By the vector synthesis method, the digital signals can change directly into radio signal. If such a circuit is realized, RF circuit and an antenna can be composed by the simple one device, and the radio is directly controlled and performed by the software processing which is the essence of software radio. This Digital-Radio conversion system of this paper give many number of communication channels being offered by PN code and offer a hardware design flexibility by digitization, therefore it decrease the percentage ratio of hardware of system and give a more flexible function of software basis. In this paper, this proposed Digital-Radio conversion system is called D/R converter, and the principle of this D/R converter, radio signal generation algorithm is explained and the performance characteristics of proposed algorithm is shown in time base by the computer simulation method.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.1125-1130
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• 2006

An air source heat pump system producing the ice and water storage energy for cooling and heating of building has been proposed. Cycle design and simulation considering energy balance between heating and cooling capacity has been carried out. The roles of the capacity controlled compressor, refrigerant heating device and air preheating are investigated in detail. System control logic for meeting the predetermined heating capacity when the system is operated at cold climate condition is suggested. Some anticipated problems of the proposed system are also described.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.271-271
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• 2018

그래픽 처리 장치(GPU: Graphic Processing Units)는 그래픽 처리에 특화된 수많은 산술논리연산자 (ALU: Arithmetic Logic Unit)와 이에 관련된 인스트럭션Instruction)으로 인해 중앙 처리 장치(CPU: Central Processing Units) 보다 훨씬 빠른 계산 처리를 수행할 수 있다. 최근에는 FORTRAN에 의해 구현된 많은 수치모형들이 현실적인 모델링 방법의 발달로 인해 더 많은 계산량과 계산시간을 필요로 한다. 이 연구에서는 GPU 상의 범용 계산GPGPU : General-Purpose computing on Graphics Processing Units) 기반 운동파 강우유출모형(Kinematic Wave Rainfall-Runoff Model)이 CUDA(Compute Unified Device Architecture) FORTRAN을 사용하여 구현되었다. CUDA FORTRAN 운동파 강우유출모형의 계산 결과는 검증된 CPU 기반 운동파 강우유출모형의 계산 결과와 비교하여 검증되었으며, 잘 일치함을 보여 주었다. CUDA FORTRAN 운동파 강우유출모형은 CPU 기반 모형에 비해 약 20 배 더 빠른 계산 시간을 보였다. 또한 계산 영역이 커짐에 따라 CPU 버전에 비해 CUDA FORTRAN 버전의 계산 효율이 향상되었다.