IEEE C37.119-2005 pdf free.IEEE Guide for Breaker Failure Protection of P ower Circuit Breakers.
This guide is intended to help the relay engineer understand the application considerations when applying breaker failure protection (BFP) to power circuit breakers. The discussion is limited to those instances where the breaker does not clear the fault after a protective relay has issued a command to open (trip) the circuit breaker. Failure to close, failure while closed, and failure while open are not discussed. The intent of this guide is not to give the reader methods of protecting a power circuit breaker from failing; rather, it is to give the reader a guide in how to detect that a breaker has failed to clear a fault, and how to electrically isolate the fault after the breaker has failed to clear the fault.
2. Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document(including any amendments or corrigenda) applies.
IEEE Std C37.102- 1995, IEEE Guide for AC Generator Protection.
IEEE Std C37.1 13-1999, IEEE Guide for Protective Relay Applications to Transmission Lines.
3.2 Definitions
3.2.1 backup protection: A protection scheme for the same zone of protection as the primary protection 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.
3.2.2 breaker failure protection (BFP): This protection is specifically relied upon to take appropriate action to clear a fault when the breaker that is normally expected to clear the fault fails to do so for any reason.
3.2.3 control timer: A timer that limits the amount of time the breaker failure scheme is active after initiation.
3.2.4 critical clearing time: the longest time that fault conditions may persist before system stability is lost.
3.2.5 local breaker failure protection: A backup protection system that is in the same substation as the pri- mary protection, so it does not suffer from the disadvantages of the remote backup protection. However, it may use some of the same equipment, such as transducers, batteries, and circuit breakers as the primary pro- tection and can therefore fail to operate for the same reasons as the primary protection.
3.2.6 primary protection: The main protection system for a given zone of protection that operates in the fastest time and removes the least amount of equipment from service.
3.2.7 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 sys- tem matured, it became increasingly difficult for remote protection to detect (see) all the faults that the pri- mary protection could detect.IEEE C37.119 pdf download.