CAJ | 학술논문

模块化多电平换流器（MMC）已成为最具前景的多电平技术，分析了以MMC为核心换流器的光伏并网逆变器的原理。并对MMC涉及的关键技术：MMC的调制和电压均衡进行了研究，提出了动态直接调制法和电容电压简化排序的均衡策略。在系统级采用传统光伏并网逆变器的双闭环控制方法，构建了完整的基于MMC的光伏并网逆变器的仿真模型。结果表明：采用MMC作为核心换流器并基于普通双闭环控制设计光伏并网逆变器的方案不仅是可行的，而且具有低谐波等优势。
모괴화다전평환류기（MMC）이성위최구전경적다전평기술，분석료이MMC위핵심환류기적광복병망역변기적원리。병대MMC섭급적관건기술：MMC적조제화전압균형진행료연구，제출료동태직접조제법화전용전압간화배서적균형책략。재계통급채용전통광복병망역변기적쌍폐배공제방법，구건료완정적기우MMC적광복병망역변기적방진모형。결과표명：채용MMC작위핵심환류기병기우보통쌍폐배공제설계광복병망역변기적방안불부시가행적，이차구유저해파등우세。
Modular multilevel converter (MMC) topology has become the most attractive multilevel technology since it has been proposed. This paper analyzes the working principle of the grid-connected PV inverter with MMC as the core converter. The key technologies of MMC such as modulation and voltage balancing are studied and dynamic direct modulation method and simplified capacitor voltage sequencing are proposed. With the system level control using conventional double closed-loop controller, a simulation model of whole grid-connected PV inverter based on MMC is built. The simulation results confirm that the scheme of designing grid-connected PV inverter based on MMC technology and conventional system level controller is not only feasible but also has low harmonic advantage.