田湾核电3#、4#机组主母线强迫风冷控制柜上下级保护不匹配问题的分析与处理

Analysis and Handling of the Problem of Unmatched Protection between the Upper and Lower Levels of the Forced Air Cooling Control Cabinet for the Main Busbars of Units 3 and 4 of Tianwan Nuclear Power Plant

在低压配电系统中,因线路某一处故障导致整个配电线路跳闸停电会引发严重结果,因此选择性保护对于保证系统供电可靠性是极其重要的。本文通过对田湾核电3#、4#机组主母线强迫风冷控制柜上下级保护不匹配问题进行分析,研究制定了处理措施,提升了低压配电系统的供电可靠性,同时提出了后续措施和建议。

In low-voltage distribution systems,the phenomenon of tripping and power outage of the entire distribution line due to a fault in one part of the line is not allowed.Therefore,selective protection is extremely important to ensure the reliability of system power supply.This article analyzes the mismatch between the upper and lower protection of the forced air cooling control cabinets for the main busbars of Tianwan Nuclear Power Units 3#and 4#,studies and develops measures to improve the power supply reliability of the low-voltage distribution system,and proposes follow-up measures and suggestions.