The optimization of 500 kV breaker failure protection

With the development of electric network, fault Critical Clearing Time (CCT) becomes shorter and shorter. Breaker failure influence to system stability more and more deeply. The main factors of fault clearing time includes protection releasing time, inherent breaker opening time, arc extinction time, current element returning time. Distribution and maximum of each component are analysed. Setting and logic optimization of breaker failure protection is submitted. Optimized setting had been used in some key station in CSG.