• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2006년 제4회 한국유체공학학술대회 논문집
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• pp.565-568
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• 2006

This paper achieved dynamic characteristics with test to use solenoid valve for flight model that have present. Designed pressure control virtual system which PWM solenoid valve to use test result. Examination compared solenoid valve dynamic characteristics in atmosphere and cryogenic fluid and presented technique and valuation method that measured upstream and down stream pressure of solenoid valve, as well as, temperature, excitation voltage etc. These test results could confirm solenoid valve response time and maximum using frequency characteristic at use in atmosphere and cryogenic temperature and this derived design variables pressure control system from those bases.

• Proceedings of the KIEE Conference
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• 대한전기학회 2004년도 춘계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.150-154
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• 2004

본 연구에서는 멀티 레벨 인버터의 파워 스펙트럼을 광대역으로 분산시키기 위한 멀티 캐리어 Random PWM기법을 제안하였다. PD(phase disposition)방식 및 H(hybrid)방식의 멀티 캐리어 Random PWM을 단상 cascade H-브리지 멀티 레벨 인버터와 3상 hybrid 멀티 레벨 인버터에 적용하였다. 각 방식에 따른 출력 전압/전류 파형 및 고조파 스펙트럼을 PSIM에 의하여 확인 하였으며, 제안된 방식의 타당성을 입증할 수 있었다.

• Proceedings of the KIEE Conference
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.426-428
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• 1997

This paper presents the linearized optimal PWM techniques for current source GTO converter. This proposed method is to linearize an optimal PWM modulation strategy so that the turn-on/off-periods of the GTO switches can be computed on-line in real-time for any modulation index. This allows the rapid and continuous regulation of the DC output current while producing the sinusoidal AC input current waveform and unit power factor.

• Proceedings of the KIEE Conference
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• 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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• pp.630-633
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• 1997

This paper describes a design of a single phase PWM converter for high speed train. Parallel operation and control method of four Quadrant PWM converters are described. Simulation and modelling of the converters is performed. Capacity of the converter/inverter and power circuit for high speed traction system designed. And harmonic contents of AC line current's are analyzed. The results of the simulation are presented.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• 제26권1호
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• pp.29-37
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• 2012

A simple and effective dead time compensation scheme for a PWM inverter-fed permanent magnet synchronous motor (PMSM) drive using the model reference adaptive control (MRAC) and coordinate transformation is presented. The basic concept is to first transform a time-varying disturbance caused by the dead time and inverter nonlinearity into unknown constant or slowly-varying one by the coordinate transformation, and then use the MRAC design technique to estimate this parameter in the stationary reference frame. Since the MRAC scheme is a suitable way of estimating such a parameter, the control performance can be significantly improved as compared with the conventional observer-based method tracking time-varying parameters. In the proposed scheme, the disturbance voltage caused by the dead time is effectively estimated and compensated by on-line basis without any additional circuits nor existing disadvantages as in the conventional methods. The asymptotic stability is proved and the effectiveness of the proposed scheme is verified.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 한국조명전기설비학회 2008년도 춘계학술대회 논문집
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• pp.245-248
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• 2008

This paper gives a description of the mode'ling and control of a single phase PWM(Pulse Width Modulation) converter for HEMU-400X(High-speed Electric Multiple Unit - 400 km/h experiment). The converter is part of a Auxiliary power unit supplied by the 25[kV], 60[Hz] overhead line. A model of the converter in a synchronously rotating reference frame of coordinates is used to develop a new type of control. The control system has separate controllers for the active and reactive current, permitting the free choice of the power factor. This paper proposes a new control method of PWM converter for Auxiliary power unit.

• Proceedings of the KIPE Conference
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.357-361
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• 1998

A new current controlled PWM technique for a 3-level inverter has been proposed and described in the paper. The proposed current control has the simple structure without needing to calculate the switching angles of the voltage vectors. The output in the proposed inverter contains less harmonic content than that of a conventional current controlled PWM controller, since the current control can be applied to the 3-level inverter. In addition, the proposed current controlled PWM technique has lower switching frequency than that of a conventional current controlled PWM technique at the same current limit. The control method and the performance for a proposed 3-level inverter has been discussed and investigated by the computer simulation.

• Proceedings of the KIPE Conference
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.374-379
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• 1998

This paper proposes a control method for three-phase PWM rectifier using only single current sensor in DC link. A PWM modulation strategy for reconstructing three phase current from the DC link current is given. The states of the rectifier switch are modified so that all phase currents can be reconstructed in a switching period although one of active vectors is applied only for a short time. Therefore, a novel current control using an adjustment scheme of the modulation signal for a three-phase PWM rectifier will be discussed, and verified with the experimental results.

• Proceedings of the KIPE Conference
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• 전력전자학회 2006년도 전력전자학술대회 논문집
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• pp.128-130
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• 2006

We introduce 2[MVA] 3300[V] 7-level voltage source inverter system developed by POSCON and describe the main characteristics of inverter system i.e. PWM converter, H-bridge power module, phase shifted carrier PWM The PWM converter is a three-phase boost converter, which operates in a 4-quadrant and in a nearly unit displacement power factor. Experimental waveforms are also presented to verify the proposed method and performance of the developed system.

• Proceedings of the KIEE Conference
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.351-355
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• 1990

In this paper, we proposed a software strategy of PWM inverter, and could indentify its realization by simulation and experiment. A basic concept of software is that the PWM pattern of inverter decided by the flux vector of induction motor tracing circle locus. The algorithm is charterized as a simplification of control circuit, abilitry on expressing control quintity as quantization and conpensation of quantization error and a switching pattern is decided by addition and substraction and high performance control is realized by 8 bits microprocessor.