Journal of Power Electronics

The Korean Institute of Power Electronics (전력전자학회)
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Discontinuous PWM Scheme for Switching Losses Reduction in Modular Multilevel Converters

  • Jeong, Min-Gyo (Department of Electrical and Computer Engineering, Ajou University) ;
  • Kim, Seok-Min (Department of Electrical and Computer Engineering, Ajou University) ;
  • Lee, June-Seok (Railroad Safety Research Division, Korea Railroad Research Institute) ;
  • Lee, Kyo-Beum (Department of Electrical and Computer Engineering, Ajou University)
  • Received : 2017.05.09
  • Accepted : 2017.10.10
  • Published : 2017.11.20
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Abstract

The modular multilevel converter (MMC) is generally considered to be a promising topology for medium-voltage and high-voltage applications. However, in order to apply it to high-power applications, a huge number of switching devices is essential. The numerous switching devices lead to considerable switching losses, high cost and a larger heat sink for each of the switching device. In order to reduce the switching losses of a MMC, this paper analyzes the performance of the conventional discontinuous pulse-width modulation (DPWM) method and its efficiency. In addition, it proposes a modified novel DPWM method for advanced switching losses reduction. The novel DPWM scheme includes an additional rotation method for voltage-balancing and power distribution among sub modules (SMs). Simulation and experimental results verify the effectiveness and performance of the proposed modulation method in terms of its switching losses reduction capability.

Keywords

References

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