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

The Korean Institute of Power Electronics (전력전자학회)
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Analysis of Neutral Point Current in T-Type Three-Level PWM Converter

T-type 3-레벨 PWM 컨버터의 중성점 전류 분석

  • Lee, Kui-Jun (Dept. of Electrical Eng., Korea Nat'l Univ of Transportation)
  • Received : 2019.10.14
  • Accepted : 2019.11.12
  • Published : 2020.02.20
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Abstract

As a T-type three-level PWM converter has several intrinsic advantages, it has been widely studied for many applications. However, it requires an additional voltage control loop for balancing each DC link voltage. Generally, satisfying this requirement involves the use of an offset voltage to provide a neutral point current without affecting other variables, such as the total DC link voltage and three-phase input current. In this study, the theoretical relationship between the offset voltage and the neutral point current is analyzed. The results can be beneficial for effective voltage balancing controller design. The effectiveness of the analytical modeling is verified by simulation and experimental results.

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References

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