IEEE C37.119-2016 pdf free.IEEE Guide for Breaker Failure Protection of Power Circuit Breakers.
backup protection: A protection scheme for the same zone of protcction as the primary protcction but may be slower and removes the same or additional equipment from service. Backup protection may be installed locally. i.e., in the same substation as the primary protection. or remotely.
breaker failure protection (BFP): A form of protection that is dcsigned to detect the failure of a circuit breaker to operate or to interrupt a fault. Upon detection of a breaker failure during a fault condition the scheme is designed to lake appropriate action to clear the fault. Upon detection of a breaker failure during a non-fault condition, the scheme may take other appropriate action.
control ti,iier: A timer that limits the amount of tune the breaker failure scheme is active after initiation,
This is a time delay on pickup timer.
coninion-mode failure: A multiple failure attributable to a common causc.
critical clearing time: The longest time that fault conditions may persist before system stability is lost.
local backup protection: A backup protection system that is in the same substation as the primary protection. However, it may USC some of the same cquipmcnt, such as transducers, batteries, and circuit breakers as the primary protection and can therefore fail to operate for the same reasons as the primary protection.
primary protection: The main protection system for a given zonc of protection that operates in the fastest time and removes the least amount of equipment from service.
remote backup protection: Historically, the first set of backup protection that was installed. It is completely independent of the relays, transducers, batteries, and circuit breakers of the primary protection system it is backing up by virtue of its physical location. Its advantage is that there are no common-mode failures that can affect both systems of protection. Its disadvantage is the fact that remote protection may remove more system elements than is desirable or necessary to clear a fault. Additionally, as the power system matured, it became increasingly difficult for remote protection to detect (see) all the faults that the primary protection could detect.
rhile infrequent, circuit breakers occasionally fail to trip, or fail to clear a fault. Depending on the power system network topology, other circuit breakers are then called upon to trip and isolate the sources contributing to the fault. Referring to Figure I, assume a fault exists between breaker 3 and breaker 4. Protective relays associated with breaker 3 and breaker 4. designed to detect faults on the line between these breakers, operate and command breaker 3 and breaker 4 to trip. In this example, breaker 3 fails to interrupt the fault current. Therefore, all sources that continue to supply fault current through breaker 3 need to be interrupted. Assuming sources at stations A and C, breakers 2. 5, and 7 need to be opened locally, or breakers 1. 6. and 8 would need to be opened remotely.
To implement remote breaker failure backup protection for breaker 3. the protective relays at breakers 1, 6, and K have overreaching elements that sense faults anywhere on the line between breaker 3 and breaker 4. and operate after a time delay, typically about 0.5 s to 1.0 s. This time delay is required to allow time for the local line protection on breaker 3 to operate. and for the breaker to successfully clear the fault. recognizing that the local protective relay scheme on breaker 3 may include time delayed tripping to coordinate with other protective relays. Remote backup protection does not have the benefit of knowing exactly when the breaker is commanded to open. Therefore, the remote backup protection needs to have sufficient time delay to accommodate all possible tripping delays.
Local HIP, on the other hand, receives a signal directly from the line protection relays at the same station as the impaired breaker, indicating when the trip command is sent to the breaker. The local I3FP only needs to wait for the breaker to successfully clear the fault, typically only 0.1 s to 0.2 s. If local BFP for breaker 3 detects a breaker failure, it commands adjacent local breakers 2, 5. and 7 to trip to clear the fault. In many cases, if a direct transfer trip (DTT) protection channel is available, it will also command the remote breaker 4 to trip and lockout. Of course, for a fault on the line between breaker 3 and 4, breaker 4 would have been tripped by the line protection relays. Hut, sending L)TT will prevent a manual or automatic rev lose of breaker 4.IEEE C37.119 pdf free download.