The Transactions of the Korean Institute of Power Electronics (전력전자학회논문지)

The Korean Institute of Power Electronics (전력전자학회)
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A Study on Operation Algorithm of Grid-Connected 3-Level NPC Inverter Considering Common-Mode Voltage and THD

공통 모드 전압 및 THD를 고려한 계통연계형 3레벨 NPC 인버터의 운용 알고리즘 연구

  • Hye-Cheon Kim (School of Electrical and Electronic Eng., Yonsei University) ;
  • Jung-Wook Park (School of Electrical and Electronic Eng., Yonsei University)
  • Received : 2022.09.27
  • Accepted : 2022.10.19
  • Published : 2023.02.20
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Abstract

A grid-connected 3-level NPC inverter is a power conversion device that connects renewable energy generators, such as photovoltaic or wind turbines to the grid. Although many studies have focused on this inverter, commercializing it requires strictly satisfying various safety and power quality-related standards. Among many standards, leakage current and grid current total harmonic distortion(THD) can be affected by external factors such as installation environment, aging, and grid conditions. Hence, inverter operations that can satisfy these standards need to be explored. In this study a 3-level NPC inverter operation algorithm using the Phase Opposition Disposition-PWM method that can effectively reduce leakage current and switching frequency adjustment to reduce THD effectively has been proposed.

Keywords

Acknowledgement

이 성과는 정부(과학기술정보통신부)의 재원으로 한국연구재단(리더연구)의 지원을 받아 수행된 연구임(No. 2020R1A3B2079407)

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