陈 科（施耐德电气（中国）有限公司，江苏省无锡市 214000）

Research on the Backup Protection and Selectivity of Upper Circuit Breaker

and Lower Circuit Breaker in Case of High Short‑circuit Current

CHEN Ke(Schneider Electric（China）Co.,Ltd.,Wuxi 214000，Jiangsu Province，China)

Abstract：The concept of current three‑section is introduced, the selectivity of upper circuit breaker and lower circuit breaker when the selectivity‑limit current Is exceeds the threshold for short‑circuit protection of the upper circuit breaker is analyzed,and relevant suggestions for practical engineering application are proposed.

Key words：series circuit of circuit breaker;selectivity;current three‑section;selectivity‑limit current;selectivity coordination table;limit breaking capacity of circuit breaker;backup protection;protection coordination

摘　要：引入电流三区段概念，主要分析在选择性极限电流Is超过上级断路器短路保护阈值时的上下级选择性问题，并就实际工程应用给出相关建议。

关键词：断路器串联回路；选择性；电流三区段；选择性极限电流；选择性配合表；断路器极限分断能力；后备保护；保护配合

中图分类号：TM561                　  文献标识码：A

doi：10.3969 / j. issn.1003 － 8493.2024.06.005