Abstract We present effective periodic surveillance test (PST) strategies enhancing the availability of nuclear safety systems with three-channel configuration in PWR (Pressurized Water Reactor), which can be used in limited space applications. The suggested PST strategies are about testing the system with the optimal surveillance test interval, the different way depending on the system operation time and testing each module in the system using the loaded test scenarios continuously and automatically. To analyze the quantitative effects of proposed PST strategies on the availability, we develop the multi-state based availability model based on the Markov model, which exactly describes the behavior of the module as well as the system level and enables the complex interrelationship among the availability parameters to be modeled systematically. Using the developed model, the unavailability with the suggested PST strategies is reduced to 47.56% compared to with the conventional PST methods. Also we show that the availability of safety-critical systems in NPPs with three-channel configuration using proposed the test strategies can be higher than that of four-channel configuration with conventional PST methods.

中文翻译：

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使用基于多状态的可用性模型有效提高核电厂安全关键系统可用性的定期监视测试策略

摘要 我们提出了有效的定期监视测试 (PST) 策略，以提高 PWR（压水反应堆）中具有三通道配置的核安全系统的可用性，该系统可用于有限的空间应用。建议的 PST 策略是关于以最佳监视测试间隔测试系统，根据系统运行时间采用不同的方式，并使用加载的测试场景连续自动测试系统中的每个模块。为了分析所提出的 PST 策略对可用性的定量影响，我们开发了基于马尔可夫模型的多状态可用性模型，该模型准确地描述了模块的行为以及系统级别，并使可用性之间的复杂相互关系成为可能。参数进行系统建模。使用开发的模型，与传统的 PST 方法相比，建议的 PST 策略的不可用性降低到 47.56%。我们还表明，使用建议的测试策略的三通道配置核电厂中安全关键系统的可用性可以高于使用传统 PST 方法的四通道配置。