• Journal of Power Electronics
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• 제12권2호
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• pp.285-293
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• 2012

Multilevel inverters have gained attention in high-power applications due to their numerous advantages in comparison with conventional two-level inverters. In this paper a simplified Space-Vector Modulation (SVM) algorithm for a three-level Neutral-Point Clamped (NPC) inverter is implemented on a Freescale$^{(R)}$ DSP56F8037. The algorithm is based on a simplification of the space-vector diagram for a three-level inverter so that it can be used with a two-level inverter. Once the simplification has been achieved, calculation of the dwell times and the switching sequences are carried out in the same way as for the two-level SVM method. Details of the hardware design are included. Experimental results are analyzed to validate the performance of the simplified algorithm.

• Journal of Power Electronics
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• 제4권2호
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• pp.77-86
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• 2004

This paper presents a novel three-phase power module bridge type auxiliary resonant AC link snubber for the three-phase voltage-fed sinwave soft switching PWM inverter operating under specific instantaneous space voltage vector modulation. The operating principle of this resonant snubber is described for current source load model during one switching period, along with its design approach based on the simulation data. The performance evaluations of space vector modulation three-phase sinewave soft switching inverter with a new three-phase active auxiliary resonant AC link snubber are discussed as compared with those of three-phase voltage source-fed sinewave hard switching PWM inverter with a standard space voltage vector modulation strategy. The power loss analysis and conventional efficiency estimation of three-phase soft switching PWM inverter using ICBT modules are carried out including all the conduction power losses based upon the measured v-i characteristics of IGBT and its antiparallel diode as well as their switching losses.

• 전력전자학회논문지
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• 제14권4호
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• pp.268-277
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• 2009

본 논문은 DTC-PWM을 적용한 PMSM의 속도제어 방식을 제안한다. 제안된 DTC-PWM은 기존의 DTC 방식과 PWM을 결합한 방식으로 스위칭 신호를 발생하는 구조를 가진다. 제안된 방식에서 실제 토크는 기존의 DTC 방식과 같이 추종되지만, 스위칭 신호는 토크 오차와 제어규칙에 따라 PWM 방식으로 제어한다. 토크와 자속을 제어하기 위한 스위칭 신호는 하나의 유효전압벡터와 영전압벡터로 구성되는 비대칭 스위칭 방식이 적용된다. 제안된 방식은 SVPWM과 같이 복잡한 계산없이 간단한 PWM의 연산으로 제어기를 구성하여 토크와 자속을 연속적으로 제어할 수 있다. 제안된 방식은 PMSM의 속도 제어 실험을 통하여 그 성능을 검증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.333-335
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• 1996

A method for detecting the three-phase currents of a voltage-fed pulsewidth modulated(PWM) inverter is proposed by utilizing only one current sensor placed on the dc-link. The proposed space vector PWM technique is two phase modulated PWM, this enables to detect the phase currents from only one DC link current sensor. The proposed method is simple, reduces the cost, and provides the small detection errors.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 A
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• pp.307-312
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• 1994

In this investigation the PFM(Pulse Frequency Modulation} will be used for optimizing PWM inverter pulse pattern. In traditional the pulse frequency of PWM is kept const. But modulated PWM's frequency in this study, the sinusoidal inverter's performance should be improved. The PWM pulsepatterns are definitely controlled so that the time-integral function of the voltage vectors in the space vector notation may show a circular locus. Further, performance index will be minimized because of minimizing distortion of output current. Finally, we will implement itusingsingle-chip microprocessor.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제53권4호
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• pp.262-268
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• 2004

This thesis is proposing novel RPWM (Random PWM) techniques that can locate PWM pulse to do random. RPWM techniques to propose locates SVPWM (Space Vector PWM) pulse by number of each random and principle to locate of pulse applies different random function and locate pulse. For propriety verification of proposed techniques, achieve an simulation and experiment that use MATLAB/SIMULINK about proposed RPWM techniques algorithm and IGBT inverter composition that use DSP(TMS320C31). Specially, analyze harmonic spectra of inverter output current when the induction motor speed is more than 10,000 rpm, confirm that RPWM's effect in high speed degree appears. Proposed RPWM techniques propriety prove from reduction effect of harmonic magnitude that corresponds to an integer times of switching frequency.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 F
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• pp.1905-1907
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• 1998

The multi-level approach seems to be best suited to high power, high voltage ac drives with low torque ripple and fast dynamic response. If high control performance is required, space vector control becomes desirable, and the task becomes time critical. In this paper, a simplified space vector PWM method for the control of a three level inverter is proposed. As the PWM is simple in structure, it is easy to implement and the fluctuation of the neutral point potential of DC link can be supressed effectively. The simulation results demonstrate that the proposed PWM strategy can be applied to high power, high voltage inverter systems. And its application to multi-level inverter is easily done on the same principle.

• Journal of Power Electronics
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• 제3권4호
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• pp.239-248
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• 2003

This paper presents a novel prototype of three-phase voltage source type zero voltage soft-switching inverter with the auxiliary resonant snubbers suitable for high-power applications with IGBT power module packages in order to reduce their switching power losses as well as electromagnetic conductive and radiative noises. A proposed single inductor-assisted resonant AC link snubber circuit topology as one of some auxiliary resonant commutation snubbers developed previously to achieve the zero voltage soft-switching (ZVS) for the three-phase voltage source type sinewave PWM inverter operating under the instantaneous space voltage vector modulation is originally demonstrated as compared with the other types of resonant AC link snubber circuit topologies. In addition to this, its operation principle and unique features are described in this paper. Furthermore, the practical basic operating performances of the new conceptual instantaneous space voltage vector modulation resonant AC link snubber-assisted three-phase voltage source type soft-switching PWM inverter using IGBT power module packages are evaluated and discussed on the basis of switching voltage and current waveforms, output line to line voltage quality, power loss analysis, actual power conversion efficiency and electromagnetic conductive and radiative noises from an experimental point of view, comparing with those of conventional three-phase voltage source hard-switching PWM inverter using IGBT power modules.

• 전력전자학회논문지
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• 제7권2호
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• pp.194-204
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• 2002

본 연구에서는 각 상의 PWM 펄스를 개별적으로 랜덤하게 위치시킬 수 있는 새로운 2상 공간벡터 RPWM (Random PWM) 기법을 제안하고 있다. 제안된 방식은 각 2상 펄스들을 변조 구간 내에서 임의의 위치에 랜덤하게 배치하고 이를 기준으로 한 인버터 스위칭에 의해 고조파의 스펙트럼을 광대역화 하는 RPWM 기법이다. 제안된 방법의 타당성을 검증하기 위하여, 16비트 고성능 마이크로 콘트롤러Cl67 기반의 실험을 수행하였다 제안된 2상 RPWM에 의한 인버터 출력 선간 전압과 직류 링크 전류의 고조파 스펙트럼 및 모터의 가청 스위칭 소음 저감효과를 종전의 방식과 비교 검토하였으며, 제안된 방법의 우수성을 입증할 수 있었다.

• 전력전자학회논문지
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• 제23권5호
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• pp.336-344
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• 2018

This study proposes a new PWM method for leakage current reduction and neutral point (NP) current control in three-phase three-level converter employed in bipolar DC distribution systems. The proposed PWM method uses medium vectors only when there is no need to control the NP current. Thus, common mode voltages are held constant to realize zero leakage current. Some space vectors that produce low-frequency common mode voltages are employed to minimize leakage currents when the average NP current needs to be a positive or negative value. The proposed space vector PWM is implemented based on barycentric coordinate. The validity of the proposed PWM method is verified by simulations and experiments.