“…Suppose fault occurs on line 3-4, according to the algorithm in Section 2.2.1, the correlated breaker sequence is T = (0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0) T , that is, breakers CB [3][4] and CB . After the area main computer issues the tripping command at t = 0.4 s, the current through breaker CB 4-3 is still bigger than δ; thus breaker CB 4-3 fails and the breaker failure algorithm is needed.…”