Abstract: In the process of high-speed train running, the time spent in the level transition of train control system and the success rate of the level transition seriously influence the safety of train operation and traffic efficiency. Level transition between CTCS-2 and CTCS-3 and level transition under degraded scenarios caused by typical equipment failures are modeled on colored Petri nets respectively, which models the information exchange between Radio Block Center（RBC）, on-board equipment and fixed balises. This paper analyzes the influence of the speed of the train to the efficiency and the success rate of level transition, and the situation in the failure downgrade. The result shows that the models meet the requirements of safety and compatibility of CTCS-3 train control system.

Key words: Chinese Train Control System（CTCS）, Colored Petri Nets（CPN）, level transition

摘要： 在高速列车运行过程中，列控系统等级转换过程所用的时长和转换成功概率，直接影响列车运行安全和行车效率。利用有色Petri网对CTCS-3级列控系统和CTCS-2级列控系统之间等级转换以及典型设备故障导致降级场景分别建模，模拟等级转换过程中RBC（Radio Block Center，无线闭塞中心），车载设备，有源应答器之间的信息交互过程。分析了列车速度对等级转换实时性的要求和对转换成功概率的影响，以及突发降级的可能性，结果表明建模方法满足CTCS-3级列控系统的安全性和兼容性要求。

关键词: 中国列车控制系统（CTCS）, 有色Petri网, 等级转换