中文摘要：

面向核电设备冷却水泵（简称核电设冷水泵）转轴的功能安全评估是减少核电设备安全问题的重要手段之一。针对核电设冷水泵转轴故障突变时功能安全评估问题，提出了一种基于突变理论的核电设冷水泵转轴功能安全完整性评估方法。首先，从核电设冷水泵转轴多传感器监测数据中提取故障特征，故障特征融合结果作为预测参数；其次，采用预测参数构建转轴性能衰退轨迹路径，基于蒙特卡罗方法计算转轴累积失效概率；最后，基于尖点突变理论计算转轴危险失效概率，并评估转轴功能安全完整性等级，并采用核电设冷水泵转轴状态监测数据进行了实验验证。结果表明，当核电设冷水泵转轴存在故障突变时，基于突变理论结合性能衰退状态监测的方法，可以提高核电设冷水泵转轴功能安全完整性评估结果的准确性。

英文摘要：

The functional safety evaluation of the component cooling water pump shaft is one of the important means to decrease nuclear equipment safety problems in nuclear power plants. Aiming at the functional safety evaluation of the component cooling water pump shaft in abrupt faults in nuclear power plants, a method for the functional safety integrity evaluation of the component cooling water pump shaft in nuclear power plants is proposed based on catastrophe theory in this paper. Firstly, the fault characteristics are extracted from the monitoring data of multiple sensors on the component cooling water pump shaft in nuclear power plants, and the fusing results of the fault characteristics are taken as the prognostic parameters. Secondly, the prognostic parameters are adopted to construct the degradation trajectory path of the shaft performance, and the cumulative failure probability of the shaft is calculated based on Monte Carlo method. Finally, the dangerous failure probability of the shaft is calculated based on the cusp catastrophe theory, and the functional safety integrity level of the shaft is evaluated afterward. The condition monitoring data of the component cooling water pump shaft in nuclear power plant were adopted to carry out experiments. The experiment results demonstrate that when abrupt fault exists in the component cooling water pump shaft in nuclear power plants, the proposed method based on catastrophe theory combining performance degradation condition monitoring can improve the functional safety integrity evaluation accuracy of the component cooling water pump shaft in nuclear power plants.