核安全级电缆耐LOCA工况能力的试验研究

Research on survival of LOCA of Class 1 E cables

为保证核电厂安全可靠运行,要求核安全级电缆在整个寿期内能经受LOCA工况,执行安全相关功能。本文以绝缘电阻为指标,以我国已运行核电厂中使用较多的2个厂家制造的核安全级电缆为样品,分析比较了不同加速老化速率、不同累积热-辐照输入对电缆耐LOCA工况能力的影响。结果表明,不同厂商制造的电缆耐相同LOCA工况的能力存在差异:在一定的加速老化速率及累积能量输入范围内,老化速率、累积能量输入对电缆A耐LOCA工况的影响不明显;而累积能量输入对电缆B耐LOCA工况能力的影响较明显。

It is required that Class1 Ecable should throughout their normal lives be capable of operating through postulated environmental conditions resulting from a LOCA.Thermal-radiation simultaneous aging and loss of coolant accident testing were carried out on two cable samples of different manufactures,which are typically used in Chinese nuclear power plants.The effects of aging rates and integrated thermal and radiation dose inputs on the ability to survive LOCA were compared on the basis of insulation resistance.The results show that different cables behave differently under the same LOCA condition with the same energy inputs.For cable A,the accident performance of cables with different aging rates and energy inputs are not significantly different.While for cable B,the integrated energy inputs might determine the survival of LOCA.