Abstract:When a fault occurs in the power system, the protection device acts to trip the circuit breakers and send signals. However, the failure of the circuit breaker of the faulty deviceleads to the malfunction of protection. In order to isolate the fault point as soon as possible and avoid further expansion of the failure range, it is particularly important to configure the breaker failure protection as backup protection. In this paper, the failure protection scheme for 220kV busbar is described in detail.