Comparison of Different Types of FCLs effect on the Transient of VSC MT-HVDC System

Low impedance and lack of zero crossing during the fault become great challenges in DC systems especially in the multi-terminal (MT) high voltage direct current (HVDC). High short circuit current threatens the power electronic devices and stability in the DC systems. Fault current limiters (FCLs) are a promising solution to address the fault current problems. This paper investigates the effect of different types of FCLs on transient performance, fault current limitation, and fault current suppression time (FCST) on the MT-HVDC system. First, the performance of different types of FCLs based on the inductor are presented. The conventional inductive FCL (IFCL), bypass FCL (BPFCL) and series-parallel FCL (S-PFCL) performance compare with each other and a case study without FCL (WFCL) during the faults. Two kinds of transient faults are considered to analyze the FCLs performance based on the permanent and temporary faults in this study. Result shows the different types of FCL can affect the transient of the DC systems. The case study is performed by using PSCAD/EMTDC software.