核电厂换料周期延长后,换料大修期间执行的定期试验项目周期也将调整。本文介绍了定期试验周期延长论证的筛选原则和论证方法。以安全壳喷淋系统为例,采用可靠性分析法论证定期试验周期延长的可行性。定量化分析结果表明,定期试验周期延长导致的系统可用度降低是可以接受的。 After the refueling cycle of nuclear power plants is extended, the period of periodic pilot projects to be carried out during refueling overhaul will also be adjusted. This article describes the screening principles and demonstration methods for the extension of periodic testing cycles. Taking the safety sprinkler system as an example, the reliability analysis method is used to demonstrate the feasibility of extending the periodic test period. The quantitative analysis shows that it is acceptable to reduce the system availability caused by the prolongation of the periodic test period.