• 제목/요약/키워드: Dynamic Voltage Sag and Harmonic Current

검색결과 3건 처리시간 0.016초

순시전압 sag 및 고조파 전류 보상을 위한 공간벡터 검출법 기반의 3상 하이브리드 직렬형 능동전력필터 (The Space Vector Detection based Three-Phase Hybrid Series Active Power Filter for Compensating Dynamic Voltage Sag and Harmonic Current)

  • 양승환;정영국;임영철
    • 전력전자학회논문지
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    • 제9권4호
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    • pp.303-310
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    • 2004
  • 본 연구에서는 순시전압 sag 및 고조파 전류 보상을 위한 공간벡터 검출법을 기반으로 한 3상 하이브리드 직렬형 능동전력필터 시스템을 제안하고 있다. 순시전안 sag 및 고조파 전류를 검출하기 위한 공간벡터 검출법은 종전의 이론에 비해 곱셈 연산 과정을 감소할 수 있고 좌표 변환이 필요치 않기 때문에 간략화한 보상 알고리즘 구현이 가능하다. 본 연구의 타당성은 전력전자전용 시뮬레이터 PSIM에 의해 정상상태와 과도상태에서 입증하였다. 그 결과 3상 교류 전원 모두에 순간적인 전압 sag가 발생되거나, 임의의 상에 왜형 및 sag가 있는 경우, 전압 보상 및 고조파 전류 보상이 모두 가능함을 입증하였다.

A Single-Phase Unified Power Quality Conditioner with a Frequency-Adaptive Repetitive Controller

  • Phan, Dang-Minh;Lee, Hong-Hee
    • Journal of Electrical Engineering and Technology
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    • 제13권2호
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    • pp.790-799
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    • 2018
  • This paper proposes a single-phase unified power quality conditioner (S-UPQC) for maintaining power quality issues in a microgrid. The S-UPQC can compensate the voltage and current harmonics, voltage sag, and swell as a dynamic voltage restorer (DVR), regardless of variations in the grid frequency. Odd harmonics are treated as even-order harmonics in a rotating frame to implement the harmonic compensators with only one repetitive controller (RC) without any harmonic extractor. The dynamic performance is improved and the delay time is reduced in the RC. The S-UPQC control scheme is designed to maintain accurate and stable operation under deviations of the grid frequency by using the Lagrange interpolation-based finite-impulse-response (LIFIR) filter approximation method. The proposed control schemes were validated through a simulation and experiment.

비대칭 입력 전압 상태를 고려한 LIDVR의 새로운 제어방법 (New Control Scheme for LIDVR Considering Asymmetry Input Voltage Conditions)

  • 한철우;김태진;강대욱;현동석
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2002년도 전력전자학술대회 논문집
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    • pp.510-514
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    • 2002
  • Power Quality and reliability are becoming important issues for critical and sensitive loads. The recent growth in the use of impactive and nonlinear loads has caused many power quality problems such as voltage flicks, harmonics and unbalances, which may cause the modem automatic devices to fail, misoperate, or shut down. This paper deals with 7-Level H-Bridge Line-Interactive Dynamic Voltage Restorer (LIDVR) system. It has the power factor near to unity under normal source voltage, can compensate the harmonic current of the load and instant interruption, and has the fast response. Currently, most of the DVR design studies are based on the assumption of the balanced three-phase system. But, actually line fault occurred $1{\phi}\;{sag}\;or\;2{\phi}$ sag. Hence, proposed new control scheme compensate asymmetry input voltage. Finally, simulation results verify the proposed 7-Level H-Bridge LIDVR system.

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