Research On The Control And Protection Scheme In VSC-HVDC Systems

Based on the research of the functions of every part of Voltage Source Converter Based High Voltage Direct Current (VSC-HVDC) system, the framework of control system of VSC-HVDC is established. After analyzing the AC single phase to ground fault when VSC-HVDC system connected to passive network or active network, the control and protection schemes are proposed in view of operation modes of VSC, As is verified by the simulation on PSCAD/EMTDC, the schemes can reach the goal after the faults that the fault terminal is still standby, the non-fault terminal is softly turned off and restrain the overvoltage and overcurrent successfully, Meanwhile, the control and protection schemes are proposed during other typical faults. Monitoring system of the laboratory model of VSC-HVDC is designed, which is useful to further research.