基于失效逻辑建模的轨道交通信号系统安全评估方法

Safety Assessment Approach to Railway Signal System Based on Failure Logic Modeling

轨道交通信号系统在架构设计阶段为了制订细化的安全需求,需要分析组件中导致系统危险源发生的组件失效事件最小割集。为了提高危险源分析结果的一致性和重用性,提出了一种基于失效逻辑建模技术的轨道交通信号系统的安全评估方法。通过设计失效逻辑模型的元模型和配置方法,基于信号系统功能设计,建立了Cecilia OCAS平台下的组件失效分析模型,使用AltaRica数据流语言描述了组件的失效逻辑行为,通过模型仿真获得了危险源的最小割集。基于通信的列车控制系统CBTC车载设备的案例研究证明:失效逻辑建模技术实现了复杂系统功能故障树的自动生成,保证了安全分析结果与系统设计变更的一致性,提高了危险源分析流程的效率。

To obtain refined safety requirements during system architecture design stage, railway signal system needs to analyse inside components the minimal cut sets of basic hazardous events leading to system hazards. To improve the consistency and reuse of hazard analysis, a safety assessment approach of railway signal system based on failure logic modeling was proposed. According to meta-model and configuration techniques of failure logic modeling, conforming to signal system function design, component failure model was established within Cecilia OCAS platform, AltaRica Dataflow language was used to depict component failure behaviors, and minimal cut sets of system hazards were attained by model simulation. The result of Communication based Train control（CBTC） system onboard equipment case study shows failure logic modeling technology realizes automated generation of complex system function fault tree, guarantees the safety analysis outcomes is in line with system design changes, and improves the efficiency of hazard analysis process.