Analysis and Treatment of Redundant Faults in UHVDC Control and Protection System

Based on ±1100kV UHVDC projects, a set of UHVDC control and protection system was designed and developed. The control and protection equipment is configured according to the pole layer and the converter layer, and the system self-monitoring and fault handling methods for the failure of specific redundant equipment are introduced in detail. When the pole layer redundancy control device fails, improve the pole layer protection device monitoring logic to prevent the pole protection device from exiting operation at the same time. When the converter layer redundancy control dev9ice fails, two types of switching and bypass pairs are designed. The inverter layer protects and locks the way. System testing shows that the UHVDC control and protection system have good performance, and the simulation results also verify the accuracy and possibility of the proposed method.