基于结构约束的硬件安全完整性等级验证研究

Study of Safety Integrity Level Validation Based on Structural Constraint

从安全仪表系统、安全完整性等级的概念出发,指出结构约束是对定量计算法确定系统结构的一种补偿措施,能够提高系统的鲁棒性。探讨结构约束的相关理论和应用问题,归纳IEC61508和IEC61511在结构约束规定方面的异同,研究利用结构约束确定硬件安全完整性等级的具体方法和步骤,并结合实例进行分析。最后提出结构约束的不足和改进方向。

Starting with explaining the concept definition of safety instrumented system and hardware safety in-tegrity level,the structural constraint which compensating the ambiguity of determining the system structure with the quantitative method was pointed out to increase the system robustness.The related theoretical and practical issues were discussed and the difference between IEC61508 and IEC615 1 1 in terms of architectural constraint requirements was summarized,including the study on the implementation and procedure of determi-ning the safety integrity level by utilizing architectural constraint and the analysis of it through examples.Final-ly,the structural constraint’s deficiency and its potential orientation for improvement were presented.