断口闪络保护的设计与工程应用

Design and application of breaker flashover protection

通过对大型发电机-变压器组在进行同步并列或退出运行过程中发生断路器断口闪络的机理进行分析,阐述了装设断口闪络保护的必要性,并对双母线和3/2断路器接线的断口闪络保护逻辑进行了详细描述,提出了闪络保护的合理设计方案。针对长期以来断口闪络保护存在的多种不同观点进行了分析,提出了断口闪络保护作用于灭磁的同时不必切换厂用电,得出采用隔离刀闸辅助触点作为断口闪络保护辅助判据方案不可取。此外,针对断口闪络保护在工程应用中与失灵保护的接口问题提出了详细的实施方案,给出了断口闪络保护的整定计算原则。

The mechanism of flashover occurred in the process of the large generator-transformer synchronization or system disconnection is analyzed, and it is necessary to configure the flashover protection in the large generator-transformer protection. Logics for flashover protection applied to duplicate and 3/2-busbar are provided, and the design schemes for flashover protection are discussed. Some different opinions for flashover protection are discussed. When flashover protection acts, it will trip the magnetic blow-out switch, it is not necessary to power-supply transfer at the same time. The scheme that the auxiliary contact of the switch is taken as the auxiliary criterion composed of the flashover protection is not correct, In addition, the detailed scheme for practice is offered for interface between flashover protection and the circuit breaker failure protection, The setting calculating principle for flashover protection is provided.