Review of the Breaker Failure Protection practices in Utilities

Breaker Failure Protection (BFP) is widely used in transmission network as backup protection. The BFP design varies from Utility to Utility, and is influenced by Utility´s past practices and their experience with electromechanical relays. The consequence of BFP mis-operation is usually severe, no matter it is false tripping or false no-tripping. It is a challenge to design a perfect BFP scheme that can achieve both security and dependability for various applications. This paper starts with the fundamentals of local and remote backup protection. The typical BFP schemes from three Utilities are followed as examples. A few mis-operation cases are presented to exemplify how the security of BFP was breached. After that, a number of aspects on how to improve the BFP scheme are explored with a focus on security side. The dependability and sensitivity of BFP scheme are also discussed for breakers associated with power equipment such as transformers and generators.