对CPR1000机组在临界启机阶段安全壳密封性的判断

The Judgment on Containment Airtightness at the Critical and Startup Stage of CPR1000

CPR1000机组正常运行时,通过安全壳泄漏率在线监测系统对其安全壳密封性进行实时监测,并以安全壳内外压差在+60 hPa(6 kPa)下的泄漏率估算值来进行考核。该系统存在固有的计算模型缺陷,即在启机积累拟合数据的初始阶段,法定泄漏率值存在一个计算“真空期”。基于某核电厂1、2号机组在线监测系统的运行实践及对历史数据的统计分析,对系统初始阶段判断安全壳密封性的思路进行了探讨,并由此提出了一套判断方案。该方案在一定程度上弥补了上述计算“真空期”的缺陷。

During the normal operation of the CPR1000, containment airtightness is monitored in real time by the Containment Leakage Monitoring System(hereinafter referred to as EPP)and is evaluated by Ql60, estimating containment’s leakage under a pressure difference of +60hPa(6 kPa) inside and outside the containment. Due to the inherent calculation model, EPP can’t figure out Ql60 in the fitting data accumulation stage. Based on the statistics of EPP’s historical operating data from a nuclear power plant, this article discusses how to estimate the containment airtightness in the initial phase and raises a scheme.