Transient Characteristics and Accommodative Current Limiting Strategy for Bidirectional Interlinking Converters in Hybrid AC/DC Microgrids  

作　　者：Xia Shen Zhikang Shuai Wen Huang Chao Shen Yang Shen Z.John Shen 

机构地区：[1]College of Electrical and Information Engineering,Hunan University,Changsha 410082,China [2]Department of Electrical and Computer Engineering,Illinois Institute of Technology,Chicago,IL 60616 USA

出　　处：《CSEE Journal of Power and Energy Systems》2024年第4期1575-1588,共14页中国电机工程学会电力与能源系统学报（英文）

摘　　要：Bidirectional interlinking converter(BIC)is the core equipment in a hybrid AC/DC microgrid connected between AC and DC sub-grids.However,the variety of control modes and flexible bidirectional power flow complicate the influence of AC faults on BIC itself and on DC sub-grid,which potentially threaten both converter safety and system reliability.This study first investigates AC fault influence on the BIC and DC bus voltage under different BIC control modes and different pre-fault operation states,by developing a mathematical model and equivalent sequence network.Second,based on the analysis results,a general accommodative current limiting strategy is proposed for BIC without limitations to specific mode or operation condition.Current amplitude is predicted and constrained according to the critical requirements to protect the BIC and relieving the AC fault influence on the DC bus voltage.Compared with conventional methods,potential current limit failure and distortions under asymmetric faults can also be avoided.Finally,experiments verify feasibility of the proposed method.

关 键 词：Bidirectional interlinking converter current limiting fault characteristic hybrid AC/DC microgrid variation/oscillation of DC bus voltage 

分 类 号：TM727[电气工程—电力系统及自动化] TM46