• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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• pp.677-680
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• 2003

The control of the SRM(Switched Reluctance Motor) is usually based on the non-linear inductance profiles with positions. So determination of optimal switching angle is very different. we present self-tuning control of SRM for maximum torque and efficiency with phase current and shaft position sensor During the sample time, micro-controller checks the number of pre-checked pulse. After micro-controller calculates between two data, it move forward or backward turn-off angle. When the turn-off angle is fixed optimal turn-off angle, turn-on angle moves forward or backward by a step using self-tuning control method. And then, optimal turn-off angle is searched once again. As such a repeating process, turn-on/off angle is moves automatically to obtain the maximum torque and efficiency. The experimental results are presented to validate the self-tuning algorithm.

• Journal of Power Electronics
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• 제12권2호
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• pp.344-356
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• 2012

In recent years, multilevel technology has become an effective and practical solution in the field of moderate and high voltage applications. This paper discusses an APF with a three-level NPC inverter. Obviously, the application of such converter to APFs is hindered by the problem of the voltage unbalance of DC capacitors, which leads to system instability. This paper comprehensively analyzes the theoretical limitations of the neutral-point voltage balancing problem for tracking different harmonic currents utilizing current switching functions from the space vector PWM (SVPWM) point of view. The fluctuation of the neutral point caused by the load currents of certain order harmonic frequency is reported and quantified. Furthermore, this paper presents a close-loop digital control algorithm of the DC voltage for this APF. A PI controller regulates the DC voltage in the outer-loop controller. In the current-loop controller, this paper proposes a simple neutral-point voltage control method. The neutral-point voltage imbalance is restrained by selecting small vectors that will move the neutral-point voltage in the direction opposite the direction of the unbalance. The experiment results illustrate that the performance of the proposed approach is satisfactory.

• Journal of Power Electronics
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• 제11권4호
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• pp.490-498
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• 2011

This paper presents a novel analysis, design, and implementation of a battery charging three-phase high frequency semi-controlled power converter feasible for plug-in hybrid electric vehicles. The main advantages of the proposed topology include high efficiency; due to lower power losses and reduced number of switching elements, high output power density realization, and reduced passive component ratings proportionally to the frequency. Additional advantages also include grid economic utilization by insuring unity power factor operation under different possible conditions and robustness since short-circuit through a leg is not possible. A high but acceptable total harmonic distortion of the generator currents is introduced in the proposed topology which can be viewed as a minor disadvantage when compared to traditional boost rectifiers. A hysteresis control algorithm is proposed to achieve lower current harmonic distortion for the rectifier operation. The rectifier topology concept, the principle of operation, and control scheme are presented. Additionally, a dc-dc converter is also employed in the rectifier-battery connection. Test results on 50-kHz power converter system are presented and discussed to confirm the effectiveness of the proposed topology for PHEV applications.

• 정보처리학회논문지C
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• 제17C권1호
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• pp.129-134
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• 2010

IPS(Intelligent Power Switch)는 내부에 논리 회로를 포함한 반도체 스위치 소자로, 논리 회로를 통한 부하의 능동적 제어를 가능하게 함으로써 기존의 차량 내 적용된 퓨즈 및 릴레이 소자를 대체할 스위칭 소자로서 각광받고 있다. 이러한 IPS의 능동적 역할을 활용하기 위해서는 각 IPS 소자를 제어할 수 있는 제어 시스템과 각 소자 및 시스템을 연결하기 위한 통신 시스템이 마련되어야 한다. 따라서 본 논문은 IPS 소자를 사용한 제어 회로 및 제어 알고리즘을 제안하고, 차량용 통신 시스템으로 널리 사용되는 CAN 프로토콜을 사용한 각 소자와 시스템 간의 통신 시스템을 제안한다.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권3호
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• pp.150-157
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• 2002

This paper presents preliminarily an implementation of digital high-performance motion control system of Reluctance Synchronous Motor (RSM) drives with direct torque control (DTC). The system consist of stator flux observer, torque estimator, two hysteresis band controllers, an optimal switching look-up table, IGBT voltage source inverter, and TMS320F240 DSP controller made by Texas Instruments. The stator fluff observer is based on the combined voltage and current model with stator flux feedback adaptive control, and the input of the observer are the stator voltage and current of motor terminal for wide speed range. The rotor position and speed sensor used 6000 pulse/rev encoder. In order to prove rightness of the suggested control algorithm, we have some simulation and actual experimental system at $\pm$20 and $\pm$2000 rpm. The developed digitally high-performance motion control system+ are shown a good response characteristic of control results and high performance features using 1.0kW RSM which has 2.57 Ld/Lq salient ratio.

• 열처리공학회지
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• 제16권3호
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• pp.148-158
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• 2003

In this study, a user oriented CFD program for optimum design of a regenerative combustion furnace, REBURN was developed. For user's convenience, user friendly Graphic User Interface was made and the renumbering interface program was developed in order to directly input any generated mesh system from ICEM CFD/FEA. Also an automatic processing system for switching mode was developed. The program was verified through compahng with commercial CFD code about regenerative combustion furnace. Then, numerical simulation of real walking beam furnace used in real industry was performed and the parametric analysis was studied about the arrangement mode. As a results, the uniform temperature was appeared in the cross mode.

• 한국통신학회논문지
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• 제30권11A호
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• pp.1035-1046
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• 2005

본 논문은 On Board Processing(OBP) 위성종신 중계기시스템에 대한 채널할당방식과 그 성능에 대하여 분석하였으며 채널할당의 효율을 개선하기 위한 CRA와 DRA에 대한 개선방식을 제시하였다. 수학적 분석과 시뮬레이션을 통해서 시스템의 성능을 평가한다. 실시간과 비실시간 서비스를 구분하였으며 음성, 화상과 같은 실시간 서비스는 지연민감성을 고려하여 우선순위를 높게 고려하였다. 탑재교환기는 CRA와 DRA의 두가지 할당방식을 역동적으로 활용한 알고리즘을 사용하여 채널 효율을 높이는 우수한 기법을 소개한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 학술대회 논문집 전문대학교육위원
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• pp.47-52
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• 2001

This paper presents a high-performance control system for Reluctance Synchronous Motor (RSM) drives with direct torque control (DTC). The system consist of stator flux observer, rotor position/speed estimator, torque estimator, two hysteresis band controllers, an optimal switching look-up table, IGBT voltage source inverter, and F240/C31DSP controller by using fully integrated control software. The stator flux observer is based on the combined voltage and current model with stator flux feedback adaptive control that inputs are current and voltage sensing of motor terminal with estimated rotor angle for wide speed range. The rotor position is estimated by the observed stator flux-linkage space vector. The estimated rotor speed can be determinated by differentiation of the rotor position used only in the current model part of the flux observer for a low speed operating area. To prove the suggested control algorithm, we have a simulation and testing at actual experimental system. The developed digitally high-performance position sensorless control system are shown a good motion control response characteristic results and high performance features using 1.0Kw RSM.

• 한국컴퓨터정보학회논문지
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• 제4권4호
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• pp.101-112
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• 1999

NPEG은 ISO 산하의 표준화 위원회에서 동영상 압축 기술의 필요에 의해 표준화된 동영상 압축 기술로 통신상에서 더 높은 비트율의 고화질 동화상 실현의 요구에 의해 1995년에 MPEG 2가 개발되었다. 본 논문에서는 VBR MPEG의 코드화된 완전한 동화상 통신을 위해 비선형 시계열 방식으로 효율적이고도 정확한 TAR모델 설계 알고리즘을 제안하며 실질적인 동영상 비디오 추적에 대한 통계적 특성을 보여주는 시뮬레이션 결과를 제시하고자 한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 A
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• pp.47-50
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• 1997

The FEM(Finite Element Method) can be used to analysis SRM(Switched Reluctance Motor) as it can account for the salient pole geometry of the stator and rotor and the nonlinear properties of the magnetic materials. However, FEM requirers a lot of computer memory and computing time because, the kind of SRM drivers is verity and the switching strategies are various for one SRM driver. In this paper we proposed the method of analysis of a SRM which results are similar to FEM and has very short computing time. The Inductance and torque for each phase current at each rotor position are calculated by using two-dimensional nonlinear FEM analysis. Using the look-up table of inductance and torque and the voltage equations of SRM we obtained the phase current and torque. To verify proposed algorithm, 3 phase 6/4 SRM is analysed and found a good agreement with FEM results. And computing time is about 1/1600 of the FEM analysis.