Statistical Analysis of HVDC Transmission Protection Operational Defects in Hubei Power Grid

In recent years, events which DC systems have been shut down or blocked due to DC protection system failures have occurred occasionally. By analyzing the blocking event of DC converter station of the State Grid Corporation in recent ten years, it can be concluded that the sampling system failure, secondary circuit fault, board fault, host fault, etc. of the protection system caused more than 10% of the DC system blocking which seriously affects safe and stable operation of DC system. Therefore, statistical analysis of defects in DC transmission protection operation is required, providing basis for subsequent research on indicators and methods of DC protection reliability evaluation.