基于DeviceNet总线的双CPU冗余实现

Implementation of dual CPU redundant control based on DeviceNet field bus

介绍了一种基于DeviceNet现场总线的双CPU冗余实现,双CPU冗余设计对提高分布式计算系统(DCS,Distributed Computer System)可靠性有重要意义.两个CPU处理单元与多个数据I/O单元通过一个现场总线连接,CPU处理单元中运行的DeviceNet客户机和服务器程序实现两个处理器单元之间的数据同步及对各个数据I/O单元的冗余控制.当主CPU单元发生严重故障停止运行时,从CPU单元中运行的伪组2客户机程序帮助从CPU单元快速完成主从切换,在不到8 ms的时间内接管整个系统.该研究应用于某专用DCS系统过程控制站的设计中,提高了系统的可靠性.

An implementation of dual CPU（central processing unit） redundant control based on DeviceNet field bus was introduced.Dual CPU redundant design played an important role to improve the DCS（distributed computer system） reliability.In the implementation,two CPU units and some data I/O（input/output） units were connected through a DeviceNet field bus,and DeviceNet client/server programs running in the CPU units implemented the data synchronization between the two CPU units as well as the redundant control over data I/O units.When the main CPU unit encountered some serious errors and broke down,a fake DeviceNet group 2 only client program running on the backup CPU unit helped to fast switching,and therefore the backup CPU unit took over the control of the whole system in less than 8 milliseconds.This design was put into practice in the design for process control stations of a special DCS system and improved the system reliability.