改进型EDF算法在计算机联锁全电子执行单元中的应用研究  

Study on Improved EDF Algorithm in Computer Interlocking Electronic Execution Unit

作　　者：张婧璇[1] 段武[2] 

机构地区：[1]中国铁道科学研究院研究生部,北京100081 [2]中国铁道科学研究院通信信号研究所,北京100081

出　　处：《铁道标准设计》2017年第7期165-169,共5页Railway Standard Design

摘　　要：针对计算机联锁全电子执行单元的安全性、可靠性、大数据量传输的要求,结合CAN总线的特点,提出一种基于指数分区的EDF动态调度算法,以此来提高CAN总线的实时性以及全电子执行单元发送消息的成功率。对改进后的EDF算法的编码进行详细的描述,通过使用量化误差的概念,推导任务的可调度性公式,以此来衡量算法的优化程度。使用Matlab中的truetime工具箱和全电子执行单元的通信数据,对该算法进行仿真实验,并与平均分区的EDF算法进行比较。仿真结果表明:本文算法能够平衡高低优先级的关系;发送消息的成功率更高。改进后的调度算法能够实现消息的动态调度,良好地解决了计算机联锁全电子执行单元中CAN总线网络资源不足时任务不可调度的问题。In view of the requirement for the safety,reliability and mega data transmission of the computer interlocking electronic execution unit and the characteristics of CAN bus,this paper proposes a EDF dynamic scheduling algorithm based on index partition to improve the real-time performance of CAN bus and success message transmission rate of full electronic execution unit. The encoding of the improved EDF algorithm is described in detail. With the quantization cost concept,the task schedulability formula is deduced and the degree of optimization algorithms is measured. The matlab＇s truetime toolbox and communication data are used to simulate algorithm and compares with the average partition EDF algorithm. The simulation results show that this algorithm can balance the relationship between high and low priorities,improve the success rate of sending messages. The improved scheduling algorithm can achieve dynamic scheduling of messages and effectively improve the real-time CAN bus,and solve the problem that the task can＇t be dispatched when CAN bus network resource is insufficient.

关 键 词：计算机联锁控制系统 执行单元 CAN总线 EDF算法 量化误差 

分 类 号：U284.3[交通运输工程—交通信息工程及控制]