基于PCHD模型的MMC-SMES无源控制策略  

Passivity-based Control Strategy of MMC-SMES Based on PCHD Model

作　　者：林晓冬 雷勇[1] 朱英伟[1] LIN Xiaodong;LEI Yong;ZHU Yingwei(College of Electrical Engineering and Information Technology,Sichuan University,Chengdu 610065,Sichuan Province,China)

机构地区：[1]四川大学电气信息学院,四川省成都市610065

出　　处：《电网技术》2019年第3期1073-1082,共10页Power System Technology

摘　　要：模块化多电平变换器(modulemultilevelconverter,MMC)由于其模块化、灵活性的特点,与传统的两电平、三电平变流器拓扑相比具有功率等级高、谐波畸变小、开关损耗低等显著优点,因此在拥有高功率密度的超导磁储能(superconducting magnetic energy storage,SMES)系统中拥有广阔的应用前景。提出了基于MMC的SMES新型拓扑结构及其无源控制策略,可有效提高受控系统的输出电能质量和动态特性。首先,建立了MMC-SMES的数学模型及其端口受控耗散哈密尔顿模型;其次,针对其运行过程中的非线性特性,通过考虑受控系统的内外部互联结构,设计了MMCSMES的无源控制策略;然后,针对MMC运行中存在的均压和环流问题,分别采用了子模块电容电压的分级式均压控制和负序二倍频坐标变换下的相间解耦控制;最后,仿真结果验证了所提出的MMC-SMES新型拓扑及其无源控制策略的有效性。Compared with conventional two/three-level converters, module multilevel converter(MMC) has the advantages of high power, small harmonic distortion and low switching loss because of its modularity and flexibility. Therefore, MMC has a broad application prospect in superconducting magnetic energy storage(SMES) system with high power density. In this paper, a novel topology of SMES based on MMC and its passivity-based control strategy are proposed to effectively improve power quality and robustness of the controlled system. Firstly, a mathematical model and a port-controlled Hamiltonian-with-dissipation(PCHD) model of MMC-SMES are established. Secondly, in order to solve the nonlinearity in operation of MMC-SMES, the passivity-based control strategy is designed considering the internal-external interaction structure of the controlled system. Then, in order to solve the problems of voltage balancing and circulating current of MMC, sub-module capacitor voltage classification balancing control and inter-phase decoupling control under negative-sequence double-frequency coordinate transformation are adopted. Finally, effectiveness of the proposed topology of SMES and its control strategy are verified through simulation studies.

关 键 词：超导磁储能 模块化多电平变换器 无源控制 端口受控耗散哈密尔顿 环流 

分 类 号：TM76[电气工程—电力系统及自动化]