• The Transactions of the Korean Institute of Electrical Engineers P
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• v.61 no.4
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• pp.186-191
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• 2012

DC Bus Electrolytic capacitors have been widely used in power conversion system because they can achieve high capacitance and voltage ratings with volumetric efficiency and low cost. This type of capacitors have been traditionally used for filtering, voltage smoothing, by-pass and other many applications in power conversion circuits requiring a cost effective and volumetric efficiency components. Unfortunately, electrolytic capacitors are some of the weakest components in power electronic converter. Many papers have proposed different methods or algorithms to determinate the ESR and/or capacitance C for fault diagnosis of the electrolytic capacitor. However, both ESR and C vary with frequency and temperature. Accurate knowledge of both values at the capacitors operating conditions is essential to achieve the best reference data of fault judgement. According to parameter analysis, the capacitance increases with temperature and the ESR decreases. Higher frequencies make the ESR and C to decrease. Analysis results show that the proposed electrolytic capacitor parameter estimation technique can be applied to reference signal of capacitor diagnosis systems successfully.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.11
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• pp.1227-1232
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• 2014

This paper relates 10% shrink from $0.13{\mu}m$ design for core devices as well as input and output (I/O) devices different from previous poly length shrink size only. We analyzed body effect with different channel length and doping profile simulation. After fixing the gate oxide module process, LDD implant conditions were optimized such as decoupled plasma nitridation of gate oxide, TEOS oxide $100{\AA}$ before LDD implant and 22o tilt-angle(45o twist-angle) LDD implant respectively to match the spice DC parameters of pre-shrink and finally matched them within 5%.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.3
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• pp.95-100
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• 2004

A control alogorithm using sliding mode and neural network for Buck type DC-DC converter is presented. Also, we conform a rightness the proposal method by comparing a theoretical values and experimental values obtained from experiment using DSP(digital signal processor). Performance comparisons made with the general hysteresis controller clearly bring out the superior performance of the proposal neural network controller. This paper will be applied to other power conversion system using the proposal neural network controller.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.676-680
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• 1991

This paper proposes fuzzy control algorithms for a DC moter speed control. The proposed algorithms are constructed by the fuzzy controller and the fuzzy compensator. The fuzzy compensator used to overcome rapidly the effects caused by the disturbance and is mounted outside of the closed loop of the fuzzy controller. The fuzzy control rules are established from human operator experience and basic engineering knowledge about the process dynamics. Simulation results show that the proposed algorithms compensate for parameter variation and disturbance.

• The Magazine of the IEIE
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• v.18 no.6
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• pp.39-46
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• 1991

칼라 비데오 프린터의 paper feeding 제어 시스템을 DC motor를 이용하여 설계하였다. 목표 spec을 만족하기 위한 H/W를 구성한 후 digital control 이론을 적용하여 loop gain K를 찾고 위상계와 속도계 gain을 결정하는 방법을 설명하였다. 한편 DC analysis를 통하여 앞에서 결정된 gain으로 설계할 경우 parameter variation에 의해 동작점이 벗어나는 것을 확인하고 system 구성 및 gain 등을 조정하여 동작점의 안정화를 가져올 수 있었다. 또한 DC analysis를 함으로써 부품의 공차를 설계할 수 있었다.

• Proceedings of the IEEK Conference
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• 2000.11b
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• pp.47-50
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• 2000

DC Gummel-Poon SPICE model parameter extraction program has been implemented. This program extracts the parameters from measured data using Levenberg-Marquardt algorithm. Measured data consist of forward and reverse Gummel plot, forward and reverse output characteristics and RE and RC measurements.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.409-413
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• 2001

This paper presents a comprehensive study result on reducing commutation torque ripples generated in brushless dc motor drives with only a single dc-link current sensor provided. In brushless dc motor drives with only a single current sensor, the commutation torque ripple suppression that is practically effective in low speed as well as high speed regions has not been reported. A proposed commutation compensation technique based on deadbeat dc-link current controller takes a closed loop control scheme and a parameter insensitive property. The proposed control method is verified through simulations and experiments.

• Journal of Power Electronics
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• v.18 no.4
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• pp.955-964
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• 2018

In this paper, an active capacitor-diode-switch (CDS) snubber is proposed for L-type current-fed isolated DC-DC converters. The proposed CDS-clamped converter has a number of advantages. It can achieve wide range zero-voltage switching (ZVS) on two switches, a continuous input current with a low ripple, a reduction of one active switch and high efficiency. The operating principles, analysis and parameter design guideline are presented. A 300 W prototype is built to test the proposed converter. Simulation and experimental results are shown at 30 V input voltage and 400 V output voltage.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.995_996
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• 2009

This paper presents a sliding mode control method for step up DC-DC converter. For high performance control of converter, it requires the robustness between the input current and the output voltage. As a result, in spite of disturbance and parameter uncertainty, the proposed controller has the robustness to control the output voltage.

• Journal of Electrical Engineering and Technology
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• v.8 no.5
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• pp.1049-1055
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• 2013

DC motors are widely used in industries like cement, paper manufacturing, etc., even today. Early fault identification in dc motors significantly improves its life time and reduces power consumption. Many conventional and soft computing techniques for fault identification in DC motors including a recent work using model based analysis with the help of fuzzy logic are available in literature. In this paper fuzzy logic and norm based wavelet analysis of startup transient current are proposed to identify and quantify the armature winding fault and bearing fault in DC motors, respectively. Results obtained by simulation using Matlab and Simulink are presented in this paper to validate the proposed work.