高精度同步与高可靠冗余的自动驾驶列车网络控制系统设计

Design of Network Control System for Automatic Train Operation with High-Precision Synchronization and High-Reliability Redundancy

随着轨道交通车辆自动驾驶技术的兴起,网络控制系统的安全性与可靠性标准越来越高,而在可信系统设计中,冗余设计是提高系统可靠性与安全性的必要技术。针对既有网络控制系统自身存在的不足,如单系统在故障后需要人为干预、原有冗余系统切换延时大、切换存在通信周期丢失以及同步精度差(延时导致毫秒级误差)等缺陷,文章提出一种高精度同步与高可靠冗余的网络控制系统设计方案,其通过采用硬件触发的软件节拍控制、优化软件通信效率以及消除累计时间差等方式来保证系统同步精度,且采用了一种基于主控制器优先从控制器跟随的策略来保证系统的无扰切换。试验验证结果表明,本方案不仅实现了主控制器和从控制器之间高精度同步,同步精度误差降低至30μs以下,且通过冗余异构设计,在避免带来共因失效的同时,显著提高了系统的可靠性与可用性。

The advent of automatic train operation(ATO)technologies for rail transit vehicles has increasingly elevated the corresponding safety and reliability standards of network control systems in this sector.Redundancy design represents a crucial technology for enhancing these system standards,particularly in the development of trusted systems.However,existing network control systems exhibit multiple deficiencies,including the need for human intervention following the failure of a single system,prolonged switching delays in existing redundancy systems,loss of communication cycles during switching,and poor synchronization accuracy(with millisecond-level errors due to delays).This paper proposes a network control system design scheme that features high-precision synchronization and high-reliability redundancy,to address these challenges.The scheme employs several methods to ensure system synchronization accuracy,including hardware-triggered software beat control,optimization of software communication efficiencies,and elimination of cumulative time differences.Additionally,the corporation of a state-following strategy,which prioritizes the master controller with the slave controller as the follower,guarantees undisturbed switching.Results from experiments conducted based on the proposed not only scheme demonstrated high-precision inter-system synchronization with errors of less than 30μs,but also highlighting a significant enhancement in system reliability and availability through a redundant heterogeneous design,without the occurrence of common cause failure.