The modular multilevel converter (MMC) is currently one of the power converter topologies which has attracted more research and development worldwide. Its features, such as high quality of voltages and currents, high modularity and high voltage rating, have made the MMC a very good option for several applications including high-voltage dc (HVdc) transmission, static compensators (STATCOMs), and motor drives. However, its unique features such as the large number of submodules, floating capacitor voltages, and circulating currents require a dedicated control system able to manage the terminal variables, as well as the internal variables with high dynamical performance. In this paper, a review of the research and development achieved during the last years on MMCs is shown, focusing on the challenges and proposed solutions for this power converter still faces in terms of modeling, control, reliability, power topologies, and new applications.

中文翻译：

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模块化多电平转换器：最新成就和挑战


模块化多电平变换器（MMC）是目前全球范围内吸引较多研究和开发的功率变换器拓扑之一。其特点，如高质量的电压和电流、高模块化和高额定电压，使 MMC 成为高压直流 (HVdc) 传输、静态补偿器 (STATCOM) 和电机驱动等多种应用的绝佳选择。然而，其独特的特性，如大量的子模块、浮动电容电压和环流，需要一个能够管理终端变量以及具有高动态性能的内部变量的专用控制系统。本文回顾了过去几年MMC 的研究和开发成果，重点讨论了该电源转换器在建模、控制、可靠性、电源拓扑和新应用方面仍然面临的挑战和提出的解决方案。