Switching Frequency Reduction Method for Modular Multi-level Converter Utilizing Redundancy Sub-module

This paper proposes a switching frequency reduction method for MMC (Modular Multilevel Converter) utilizing redundancy operation of sub-module, which can offer reduction of voltage harmonics and switching loss. The feasibility of proposed method was verified through computer simulations with PSCAD/EMTDC software. Based on simulation analysis, a hardware scaled-model of 10kVA, DC-1000V MMC was designed and manufactured in the lab. Various experiments were conducted to verify the feasibility of proposed method in the actual hardware system. The hardware scaled-model can be effectively utilized for analyzing the performance of MMC according to the modulation scheme and redundancy operation.

[1]  K. Ilves,et al.  Steady-State Analysis of Interaction Between Harmonic Components of Arm and Line Quantities of Modular Multilevel Converters , 2012, IEEE Transactions on Power Electronics.

[2]  Wenhua Liu,et al.  A Steady-State Analysis Method for a Modular Multilevel Converter , 2013, IEEE Transactions on Power Electronics.

[3]  Ping Wang,et al.  An Inner Current Suppressing Method for Modular Multilevel Converters , 2012, IEEE Transactions on Power Electronics.

[4]  W.L. Kling,et al.  HVDC Connection of Offshore Wind Farms to the Transmission System , 2007, IEEE Transactions on Energy Conversion.

[5]  Marc Hiller,et al.  Modulation, Losses, and Semiconductor Requirements of Modular Multilevel Converters , 2010, IEEE Transactions on Industrial Electronics.

[6]  Baoming Ge,et al.  Medium-Voltage Multilevel Converters—State of the Art, Challenges, and Requirements in Industrial Applications , 2010, IEEE Transactions on Industrial Electronics.

[7]  Zheng Xu,et al.  Impact of Sampling Frequency on Harmonic Distortion for Modular Multilevel Converter , 2011, IEEE Transactions on Power Delivery.

[8]  R. Marquardt,et al.  Modular Multilevel Converter: An universal concept for HVDC-Networks and extended DC-Bus-applications , 2010, The 2010 International Power Electronics Conference - ECCE ASIA -.

[9]  Zheng Xu,et al.  Suppressing DC Voltage Ripples of MMC-HVDC Under Unbalanced Grid Conditions , 2012, IEEE Transactions on Power Delivery.

[10]  U N Gnanarathna,et al.  Efficient Modeling of Modular Multilevel HVDC Converters (MMC) on Electromagnetic Transient Simulation Programs , 2011, IEEE Transactions on Power Delivery.

[11]  Lie Xu,et al.  Reduced switching-frequency modulation and circulating current suppression for modular multilevel converters , 2012, PES T&D 2012.

[12]  Alex Q. Huang,et al.  Real-Time Algorithm for Minimizing THD in Multilevel Inverters With Unequal or Varying Voltage Steps Under Staircase Modulation , 2009, IEEE Transactions on Industrial Electronics.

[13]  Staffan Norrga,et al.  A New Modulation Method for the Modular Multilevel Converter Allowing Fundamental Switching Frequency , 2012 .

[14]  Wenjing Liu,et al.  Accelerated Model of Modular Multilevel Converters in PSCAD/EMTDC , 2013, IEEE Transactions on Power Delivery.

[15]  V.G. Agelidis,et al.  VSC-Based HVDC Power Transmission Systems: An Overview , 2009, IEEE Transactions on Power Electronics.