Stability analysis of the initial period of power system restoration using the path including VSC-HVDC

The stability problem during the initial period of power system restoration is mainly related with the following aspects. It is infirmly to resist interference since the power system scale is not large. It is easy to result in instability or short circuit fault for frequently and quickly load change. It is easy to arouse generation self-excited problem for the fewer load in total. Based on these characteristics of VSC-HVDC, the transmission line including VSC-HVDC is selected to restore system and its circuit model is founded in this paper. The simulation results show that the system can keep stability when the system is in steady state and fault. There are no self-excited problems. The speed of charging the transmission line and restoring loads is high too. Because of the isolation of the direct line the impact to source can be avoided by the long AC line, as is favor of the quick power system restoration.