DOI QR코드

DOI QR Code

다양한 불평형 계통 상황에서 계통 연계형 3-레벨 NPC 컨버터의 중성점 전류 변동에 대한 해석 및 제어

Analysis and Control of Neutral Point Current Deviation in Grid Tied 3-Level NPC Converter under Various Grid Unbalanced Conditions

  • Choi, Jaehoon (Dept. of Electrical Engineering, Smart Grid Research Center, Jeonbuk National University) ;
  • Suh, Yongsug (Dept. of Electrical Engineering, Smart Grid Research Center, Jeonbuk National University)
  • 투고 : 2019.12.10
  • 심사 : 2020.04.02
  • 발행 : 2020.10.20

초록

This study introduces an analysis and control method for the variation of neutral point current in a grid-tied three-level neutral point clamped (NPC) converter under various grid imbalance operating conditions. Various fault cases with unbalanced amplitude and phase are systematically categorized and described using a unified metric called the imbalance factor. The fundamental component of neutral point current is generated under grid imbalance cases. The pattern and behavior of this fundamental component of neutral point current highly depend on the imbalance factor regardless of the particular type of grid fault cases. The control scheme for regulating the negative sequential component of AC input current effectively reduces the size of the fundamental component of neutral point current under a wide range of grid imbalance cases. The control scheme will enable a grid-tied three-level NPC converter to operate reliably and stably under various types of grid faults.

키워드

참고문헌

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