• Journal of Power Electronics
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• 제17권6호
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• pp.1637-1649
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• 2017

This paper describes an intensive analysis of a harmonic identification algorithm in non-ideal voltages source systems. The dq-axis Fourier with a positive sequence voltage detector (DQFP) is a novel harmonic identification algorithm for active power filters. A compensating current control system based on repetitive control is presented. A design and stability analysis of the proposed current control are also given. The aim of the paper is to achieve a robustness of the harmonic identification in a distorted and unbalanced voltage source. The proposed ideas are supported by a hardware in the loop technique based on a $eZdsp^{TM}$ F28335 and the Simulink program. The obtained results are presented to demonstrate the performance of the harmonic identification and the control strategy for the active power filter in non-ideal systems.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2000년도 전력전자학술대회 논문집
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• pp.752-755
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• 2000

This paper describes a new algorithm for active power filters which can be control source current symmetrically under unbalanced condition in power system. Positive sequency voltage is detected by symmetrical coordinate method and compensating reference current of active power filters is calculated using by accurate phase angle information of positive sequency voltage. The basic principle of the proposed method is described in detail and the conventional and proposed phase detecting methods are compared and discussed through the simulation results.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 전력전자학술대회 논문집(2)
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• pp.673-676
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• 2004

본 논문은 3상 입력전원의 불평형과 고조파문제를 대칭 좌표계를 통해 각각 정상분과 역상분으로 분리하여 동기 회전 좌표계 상에서 보상할 수 있는 알고리즘을 제안하였다. 동기 회전 좌표계 상에서 보상이 이루어지므로 UPQC와 같은 다양한 목적의 능동전력필터에 쉽게 적용될 수 있다 제안된 알고리즘의 타당성을 뒷받침하기 위해 시뮬레이션을 수행 하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 추계학술대회 논문집
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• pp.109-110
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• 2012

본 논문에서는 불평형 전원 전압 하에서 삼상 PWM 컨버터의 전류 보상 기법을 제안하였다. 전원 전압이 불평형인 경우 PLL(Phase Locked Loop)를 이용하여 추출한 위상각에는 왜곡 성분이 포함된다. 이러한 왜곡된 위상각으로 컨버터를 제어하는 경우 입력 전류에도 고조파가 포함되게 된다. 본 논문에서는 불평형 전원 전압 하에서도 입력 전류의 THD(Total Harmonic Distortion)를 IEEE Std. 519 규정인 5% 이내로 제한할 수 있도록 하는 전류 보상 기법을 제안하였다. 제안된 기법은 시뮬레이션을 통해 그 타당성을 검증하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 합동 추계학술대회 논문집 정보 및 제어부문
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• pp.286-289
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• 2002

In this paper, we use the PI dual control using do transformation(dq stationary frame and dq synchronous rotating frame) for series voltage sag and swell compensation algorithm. Analysis, simulation results are presented for voltage sags and swells on a three-phase unbalanced voltage source.

• KSBB Journal
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• 제10권4호
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• pp.406-420
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• 1995

Polyhydroxyalkanoates[PHAs] are the polyester of hydroxyalkanoates(HAs) synthesized by numerous bacteria as an intracellular carbon and energy storage compound and accumulated as granules in the cytoplasm of the cells under unbalanced growth condition in the presence of excess carbon source. Even though PHAs have been recognized as good candidates for biodegradable plastics, their high price compared with conventional plastics has limited their use in a wide mange of applications. To reduce the high production cost of PHAs, many group of scientists have devoted much efforts to improve productivity by employing various microorganisms and by developing efficient culture techniques. The strategies of producing PHAs to a high concentration with high productivity and their potential applications are reviewed.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 추계학술대회 논문집
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• pp.97-101
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• 2001

Recently, as the development of industry, the nonlinear load becomes increased. Because of nonlinear load, the variation of source voltage is generated by the impedace of source side flowed harmonic currents. For blocking harmonic currents by nonlinear load, a series active power filter operates blocking resistance of harmonic currents. The value of blocking resistance shows ideal compensating characteristic out of theoretically infinite value. But the blocking resistance is limited by the problem of the system stability and the capacity of inverter. In this paper, the value of optimum blocking resistance is found by a simulation in the applied system. In the case of unbalanced source voltages, each relation of the blocking resistance is shown. It is proved that blocking resistance of series active power filter relates to a passive filter.

• 전력전자학회논문지
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• 제9권5호
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• pp.420-429
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• 2004

본 논문에서는 PQR 순시전력 이론을 적용하여 3상 4선식 배전망에서 전원전압의 불평형 및 왜곡에 강인하게 동작하는 전력용 능동 필터의 제어기를 디지털적으로 설계한다. 인버터의 교류측 필터의 특성을 분석하고, 디지털 제어시스템이 내재적으로 갖고 있는 시간지연문제를 극복할 수 있는 우수한 성능의 제어기구조를 제안하며, 제어 이득을 설계한다. 전류 고조파 및 중성선 전류 고조파를 감소시키기 위하여 제어기 구조와 3중 비교삼각파 사용을 제안하고 제어 이득을 설계하였다. 디지털 구현이 용이한 삼각파 비교 PWM을 보상전류 제어 방식으로 채택하였다. 설계된 전력용 능동 필터를 PSiM 시뮬레이션을 통하여 검증하고 전류 응답성이 뛰어난 히스테리시스 PMW 결과와 비교 분석하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.803-807
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• 2001

This paper presents a new control scheme for a DVR (Dynamic Voltage Restorer) system consisting of series voltage source PWM converters. To control the negative sequence components of the source, it is necessary to detect the negative sequence components. Generally, a filtering process is used which has some undesirable effects. This paper suggests a new method for separating positive and negative sequences components. This control system is designed using differential controllers and digital filters. The positive and negative sequences are extracted and controlled individually. The performance of the presented controller and scheme are confirmed through simulation and actual experiment with a 2.5kVA prototype DVR system.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제51권4호
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• pp.203-209
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• 2002

This paper presents a new control scheme for a DVR(Dynamic Voltage Restorer) system consisting of series voltage source PWM converters. To control negative sequence component of source voltage the detection of negative sequence is necessary. Generally, filtering process is used tn do that. Through this filtering process has some problems. This paper suggests a new method of separating positive and negative sequences. This control system is designed using differential controllers and digital filters, and positive sequence and negative sequences are controlled respectively. The performance of the presented controller and scheme are confirmed through simulation and actual experiment by 2.5kVA prototype DVR.