Current-fed Modular Multilevel Converter (CMMC) for Fuel Cell and Photovoltaic Integration

Modular multilevel converters (MMCs) have demonstrated superior performance as a power conditioning stage (PCS) in several applications within low-, medium-, and high-voltage areas. Meanwhile, it is still mandatory to embrace the boosting capability within the power conditioning stage in some of these applications, such as fuel cell and photovoltaic-fed systems, due to the unregulated low-voltage (LV) output of these DC sources. As a consequence, the utilized PCS will be based on a two-stage configuration, which is seen to be a bulky solution. Hence, this paper proposes a current-fed MMC (CMMC) topology as a single-stage solution for interfacing an LV DC source with a higher voltage AC load or grid. The proposed converter embraces the boosting capability within the inversion operation, while maintaining the merits of the traditional MMC. Such converter can be utilized in both LV and MV systems, where LV MOSFETs can be utilized in the LV ones in order to benefit from their low ON-state resistance and increase the power conversion efficiency. The proposed converter is analysed and simulation results using PLECS are included in this paper for a 10 kW three-phase CMMC in order to verify its functionality and the reported analysis.

[1]  Frede Blaabjerg,et al.  A Guideline for Reliability Prediction in Power Electronic Converters , 2020, IEEE Transactions on Power Electronics.

[2]  Hirofumi Akagi,et al.  Classification, Terminology, and Application of the Modular Multilevel Cascade Converter (MMCC) , 2010, IEEE Transactions on Power Electronics.

[3]  Stephen J. Finney,et al.  LV Converters: Improving Efficiency and EMI Using Si MOSFET MMC and Experimentally Exploring Slowed Switching , 2018, IEEE Journal of Emerging and Selected Topics in Power Electronics.

[4]  Paolo Mattavelli,et al.  Analysis and Design of the Quasi-Z-Source Inverter for Wide Range of Operation , 2018, 2018 IEEE 19th Workshop on Control and Modeling for Power Electronics (COMPEL).

[5]  Jih-Sheng Lai,et al.  Fuel Cell Power Systems and Applications , 2017, Proceedings of the IEEE.

[6]  Qiuwei WU,et al.  Transition towards higher penetration of renewables: an overview of interlinked technical, environmental and socio-economic challenges , 2018, Journal of Modern Power Systems and Clean Energy.

[7]  S. Allebrod,et al.  New transformerless, scalable Modular Multilevel Converters for HVDC-transmission , 2008, 2008 IEEE Power Electronics Specialists Conference.

[8]  Prasad N. Enjeti,et al.  Design of a wide input range DC-DC converter with a robust power control scheme suitable for fuel cell power conversion , 2004, Nineteenth Annual IEEE Applied Power Electronics Conference and Exposition, 2004. APEC '04..

[9]  Paolo Mattavelli,et al.  Analysis of the three-level diode-clamped split-source inverter , 2016, IECON 2016 - 42nd Annual Conference of the IEEE Industrial Electronics Society.

[10]  Stephen J. Finney,et al.  MMC with parallel-connected MOSFETs as an alternative to wide bandgap converters for LVDC distribution networks , 2017 .

[11]  Anh-Vu Ho,et al.  Topology and Modulation Scheme for Three-Phase Three-Level Modified Z-Source Neutral-Point-Clamped Inverter , 2019, IEEE Transactions on Power Electronics.

[12]  Paolo Mattavelli,et al.  Three-Phase Three-Level Flying Capacitors Split-Source Inverters: Analysis and Modulation , 2017, IEEE Transactions on Industrial Electronics.

[13]  Paolo Mattavelli,et al.  Three-Phase Split-Source Inverter (SSI): Analysis and Modulation , 2016, IEEE Transactions on Power Electronics.