Start-Up and Dynamic Modeling of the Multilevel Modular Capacitor-Clamped Converter

Electr. & Comput. Eng. Dept., Univ. of Utah, Salt Lake City, UT, USA
IEEE Transactions on Power Electronics (Impact Factor: 5.73). 03/2010; DOI: 10.1109/TPEL.2009.2025273
Source: IEEE Xplore

ABSTRACT This paper will present the analytical proof of concept of the multilevel modular capacitor-clamped converter (MMCCC). The quantitative analysis of the charge transfer mechanism among the capacitors of the MMCCC explains the start-up and steady-state voltage balancing. Once these capacitor voltages are found for different time intervals, the start-up and steady-state voltages at various nodes of the MMCCC can be obtained. This analysis provides the necessary proof that explains the stable operation of the converter when a load is connected to the low-voltage side of the circuit. In addition, the analysis also shows how the LV side of the converter is (1/ N )th of the HV side excitation when the conversion ratio of the circuit is N . In addition to the analytical and simulation results, experimental results are included to support the analytical proof of concept.

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