面向高需求模式的安全仪表系统可靠性评估

针对高需求模式下，安全仪表系统的可靠性评估尚缺研究的现状，以1oo2冗余结构组为例，综合考虑过程需求、部件失效模式、验证测试策略和维修等因素，运用马尔可夫方法构建了结构组的可靠性分析模型，并分别对需求和测试策略对结构组可靠性的影响进行了研究。结果表明：结构组的可靠性随着需求频率及验证测试频率的增加而降低；当需求频率高于验证测试频率时，结构组的运行状态主要通过需求进行检测，反之，则通过验证测试进行检测。

Reliability Assessment of Safety-instrumented Systems Operated in High-demand Mode

Currently, the research of reliability analysis of high-demand safety instrumented systems was rare. Considering the process demands, item failure modes, proof test strategy and maintenance, a Markov model of the 1oo2 voted group was developed for the reliability analysis. After that, the effects of demand and proof test strategy on the reliability of the voted group were explored, respectively. The results show that the reliability of the voted group decreases with the demand rate and the proof test frequency. The operating state of the group is dominantly verified by demands if the demand rate is larger than the proof test frequency, and by proof tests otherwise.