基于以太网的列车通信网络冗余结构可靠性分析
Reliability analysis of train communication network redundancy based on Ethernet

摘要 列车通信网络是轨道车辆可靠安全运行的重要保障，具有可靠性高、实时性强、故障切换与恢复时间短等特点.提出基于PRP和HSR的列车通信网络结构，实现网络故障零恢复时间.在此基础上依据系统可修性和功能相关性及冗余性特点，采用DFTA对其进行可靠性建模；引入BDD和Markov矩阵分解静态子树和动态子树以优化传统故障树分析的计算量；针对具体算例对PRP、HSR、RSTP协议的可靠性指标进行量化求解与对比分析.研究结果表明：提出的PRP与HSR冗余结构和RSTP相比，平均故障间隔时间分别增长了5 764 h与5 269 h，有效提升了网络可靠性.
Abstract：Train Communication Network (TCN) is the substantial guarantee of reliable and safe operation of rail trains and is strict with performance of real-time ability, fault-switch time and reliability. Parallel Redundancy Protocol (PRP) and High-availability Seamless Redundancy (HSR) are introduced to realize zero-switch time on network fault station of TCN. Due to the characteristics of reparability, functional dependency, fault-tolerance and redundancy, Dynamic Fault Tree Analysis (DFTA) is proposed to analyze the reliability of PRP and HSR on TCN. Binary Decision Diagram (BDD) and Markov matrix are adopted to resolve static and dynamic fault tree so that the quantity of calculation is reduced. The reliability indexes of PRP, HSR and Rapid Spanning Tree Protocol (RSTP) are quantified and analyzed in detail. The analysis results show that the proposed PRP and HSR redundancy structure has increased 5 764 h and 5 269 h respectively compared with RSTP, which effectively improves the network reliability.