摘要
根据模块化多电平变流器(modular multilevel conv-erters,MMC)的工作原理和拓扑结构特点以及逆变型分布式发电系统(distributed generation,DG)的运行特点,建立了由MMC构成的DG等值系统及其交流电流控制器数学模型。运用PSCAD分析了基于MMC的DG系统动态特性,发现当直流电压大幅波动时,DG交流电流和输出功率同样出现了大幅波动的情况。针对这一问题,提出了改进的交流电流控制器,并通过仿真证明了该控制器的有效性。
According to the working principle and topological structure of modular multilevel converter （MMC） and condering the operational feature of distributed generation （DG） system, an equivalent inversion-type of DG system based on MMC and the mathematical model of its AC current controller are built. The dynamic characteristic of inversion-type of DG system is analyzed by PSCAD and it is found that under DC voltage fluctuation over wide range the AC current of inversion-type of DG system based on MMC and its output power fluctuate over wide range as well. To solve this problem, an improved AC current controller is proposed and whose effectiveness are verified by simulation results.
出处
《电网技术》
EI
CSCD
北大核心
2011年第7期42-47,共6页
Power System Technology
