CPR1000核电厂LBLOCA裕量提升研究

Research on Improving of LBLOCA Margin for CPR1000 NPP

为进一步提升核电厂安全性,核电厂用户提出了15%安全裕量的要求。为提升CPR1000核电厂大破口失水事故(LBLOCA)安全裕量,从改动最小、收益最大的角度出发,提出了两种改进措施:增加安注箱水体积和采用热棒统计分析方法(HRSM)。利用CATHARE程序,对安注箱水体积增加进行敏感性计算,以得到水体积增加量的最优值;热棒统计法中,对3个很大程度上影响计算结果的输入参数进行了抽样,并对计算结果进行统计分析,得到95%95%值(95%置信度下95%概率值)。结果表明,在采用上述两种改进措施后,CPR1000核电厂的LBLOCA安全裕量提升了6.5%。

In order to improve the safety of reactors, 15% safety margin requirement is proposed by NPP utility. To improve the large break loss of coolant accident （LBLOCA） safety margin of CPR1000 NPP, two measures were proposed considering the minimum change and the maximum benefit, including increasing the water volume in the accumu- lators （ACCs） and using hot rod statistical treatment method （HRSM）. Based on CATHARE program, the sensitivity calculation was carried out for the increase of the water volume in the ACCs, so the optimal water volume was got. In HRSM, three input parameters which greatly affected the calculation results were sampled, and the calculation results were statistically analyzed, so the 95% 95% value （95 % probability value under 95% confidence level） was got. The results show that the LBLOCA safety margin of CPR1000 NPP increases by 6.5% after using the two measures.