The requirement of a large number of sizeable capacitors in traditional modular multilevel converter (MMC) submodules is seen as a major barrier hampering its widespread use in medium-voltage applications. To reduce the value of capacitance, this paper presents a modified MMC (M-MMC) topology, which offers inherent alleviated capacitor voltage fluctuations compared with traditional MMC. Its operating principle, modulation, and capacitor voltage balancing strategies are described in detail. Moreover, a novel capacitor voltage fluctuation suppression scheme is also proposed to further reduce the second-order capacitor voltage ripples. Finally, both a three-phase prototype of M-MMC and traditional MMC have been built in the laboratory. The effectiveness of the proposed M-MMC topology and control methods is experimentally verified by comparing with the traditional MMC.
No takes yet. Share an insight, caveat, or question.
Li et al. (2015) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: