A Simple Operation Approach for Modular Multilevel Converter Under Grid Voltage Swell in Medium-Voltage Microgrids

IEEE Access

Huiqiao Liu¹  Yu Jin²  Linglin Chen³  Remus Teodorescu⁴  Frede Blaabjerg⁴  Qian Xiao⁵  Hongjie Jia⁵  Xiaodan Yu⁵ 

[1] Department of Automation Engineering, Zhonghuan Information College, Tianjin University of Technology, Tianjin, China;Department of Electrical Engineering and Automation, Harbin Institute of Technology, Harbin, China;Department of Electrical and Electronics Engineering, University of Nottingham, Nottingham, U.K.;Department of Energy Technology, Aalborg University, Aalborg, Denmark;Key Laboratory of Smart Grid of Ministry of Education, Tianjin University, Tianjin, China;

关键词: Modular multilevel converter (MMC);    microgrid;    grid fault;    grid voltage swell;    fault-tolerant operation;    zero-sequence voltage injection;   

DOI  :  10.1109/ACCESS.2019.2946087

来源: DOAJ

【 摘 要 】

Modular multilevel converter (MMC) is drawing more and more attention in medium-voltage microgrid applications. Large-scale switching-off loads and grid faults may lead to the voltage swell in microgrid, where MMC should have the ride-through ability. In this paper, a simple operation approach with the fundamental and irregular zero-sequence voltage (ZSV) injection is proposed for MMC under grid voltage swell condition. First, the fundamental ZSV injection is applied to adjust the modulation margin of three phases where the amplitude values of modulation waves in each phase can be the same. Then, if the amplitudes with fundamental ZSV injection are still in over-modulation status, the new irregular ZSV injection is added to further enlarge the operation region. In addition, the limitation of the irregular ZSV injection is analyzed. Simulation and experimental results of MMC under different grid voltage swell conditions verify the effectiveness of the proposed operation approach.

【 授权许可】

Unknown