摘要
模块化多电平变流器开关损耗低,电磁干扰小,可扩展性强,并且不同变流器的直流端可以耦合。介绍了模块化多电平变流器的结构和工作原理、内部子模块的电压平衡策略、输出电压的调制方法。在传统的双环矢量控制的基础上,通过加入动态电流限幅控制,减弱了控制环之间的冲突,提高了控制系统的动态响应能力。另外,通过采用混合调制的策略,减少了输出电压在低输出时的谐波含量。最后,通过仿真该变流器在柔性直流输电中的应用,证明所提控制方法对控制效果的改善作用。
The MMC(Modularized Multilevel Converter) has the advantages of low switching loss,small electromagnetic emission,easy expanding and possible DC coupling. Its structure and working principle,as well as the voltage balancing strategy of its internal modules and the modulation of its output voltage,are introduced. Based on the conventional cascaded vector control,the real-time current limitation control is added to decrease the interaction between two control loops and improve the dynamic performance of control system. Hybrid modulation is adopted to suppress the harmonics of low voltage output. Simulative results of MMC applied in VSC-HVDC show the effectiveness of the proposed control method.
出处
《电力自动化设备》
EI
CSCD
北大核心
2012年第4期63-66,共4页
Electric Power Automation Equipment
基金
海洋工程国家重点实验室基金资助项目(AE010803)
上海市科技发展基金资助项目(08DZ1200504
09DZ1201303)~~
关键词
变流器
模块化多电平变流器
阶梯波调制
多重载波
限幅
柔性直流输电
脉宽调制
electric converters
modularized multilevel converter
step modulation
multilevel carrier
limitation
VSC-HVDC
pulse width modulation