摘要
新型模块化多电平变换器MMC(modular multilevel converter)通过子模块电压叠加输出高电压,输出电压谐波含量少,且无需额外的滤波器和变压器,十分适用于轻型直流输电系统中。由于MMC各桥臂级联多个子模块,各子模块中通过对直流储能电容器的双向PWM斩波输出需要的电压,这就需要对各子模块电容电压进行平衡控制。基于MMC的工作原理,提出了一种经过优化的载波移相SPWM调制策略和子模块电容电压平衡控制策略。通过PCAD/EMTDC仿真软件对所提出的控制策略进行了验证,证明了该策略的可行性和有效性。
New modular multilevel converter (MMC) output through the sub-module voltage superimposed high voltage, low output voltage harmonic content, and no additional filters and transformers, are suitable for HVDC light system. Since the bridge arm MMC cascade multiple sub modules, each sub-module, by way of the DC storage capacitor PWM chopper output voltage required, which requires the sub-module capacitor volt- age balance control. MMC-based works,an optimized carrier phase SPWM modulation strategy and the sub- module capacitor voltage balance control strategies were presented. By PCAD/EMTDC simulation software of the proposed control strategy,the feasibility and effectiveness of the strategy is proved.
出处
《电气传动》
北大核心
2011年第9期34-37,共4页
Electric Drive
基金
国家自然科学基金(50907001)