RET670主变过励磁保护逻辑缺陷分析及其改进  

Improvement of RET670 transformer overexcitation protection’s programmable scheme logic

作　　者：赵晓明[1] 余志慧[2] 

机构地区：[1]浙江省电力试验研究院,浙江杭州310014 [2]杭州市电力局,浙江杭州310016

出　　处：《电力系统保护与控制》2010年第4期124-125,129,共3页Power System Protection and Control

摘　　要：介绍了一起在现场试验中发现的RET670主变过励磁保护无法启动220kV以及500kV断路器失灵保护故障。针对此现象对RET670主变过励磁保护固有逻辑及其外部可编程逻辑进行了详细的分析和试验,发现只有在提高过励磁保护出口跳闸脉宽整定时间时才能正常启动失灵保护,否则过励磁保护均无法启动失灵保护,将导致在主变故障同时220kV或500kV断路器拒动时事故扩大,存在很大的安全隐患。针对RET670过励磁保护逻辑和失灵保护逻辑无法配合的缺陷,文中提出了解决方案,可以解决RET670过励磁保护无法启动失灵保护问题。A failure startup breaker-failure protection instance of RET670 over-excitation protection,which is one of transformer protection relays, is presented in this paper.Detailed analysis of RET670 over-excitation protection’s programmable scheme logic and default logic is carried out.It finds that only in enhancing the setting time of over-excitation protection tripping pulse-width becomes a normal startup failure protection, or over-excitation protection can not start failure protection will lead to failure while in the main transformer 220 kV or 500 kV circuit breaker tripping when the accident expanded, there is a big security risk. To solve this problem,a modified programmable scheme logic （PSL） is proposed.

关 键 词：过励磁保护 失灵保护 可编程逻辑 

分 类 号：TM772[电气工程—电力系统及自动化]