摘要
研究了西门子可编程控制器(PLC)软冗余系统的软硬件组成及实现原理。典型的PLC软冗余系统由主/备的CPU、电源、I/O模块和总线等组成。一旦发生故障,备CPU接替主CPU工作,保证系统正常运行。分析了PLC软冗余系统在主CPU、电源、I/O模块和Profibus总线等分别发生故障情况下,不同故障发生时刻引发的软件中断和主备切换过程,得出了相应的主/备切换时间极限值的估算公式。分析了PLC软冗余系统的数据同步过程,得出了数据同步时间的估算公式。通过分析可知,PLC软冗余系统的主备切换时间和数据同步时间较长,适合于对实时性要求不严格的生产过程控制。
The structure of SIMATIC PLC software redundancy system and its implementation principle are studied. Typical PLC software redundancy system consists of master-backup CPU, power supply, I/ O module and field-bus. When breakdown occurs, the backup CPU runs instead of former master CPU to assure the normal operation. The changeover procedure is analyzed for different component breakdowns at different moments to get the estimation formula of corresponding maximum changeover time, and the data synchronization procedure is analyzed too to get the estimation formula of data synchronization time. Analytical results show that, the changeover time and data synchronization time of PLC software redundancy system are longer, suitable for the process control without strict requirement for real time performance.
出处
《电力自动化设备》
EI
CSCD
北大核心
2009年第2期98-101,共4页
Electric Power Automation Equipment
基金
西安市工业科技攻关计划项目(GG200334)~~
关键词
软冗余
主备切换
数据同步
可编程控制器
网络故障
software redundancy
master-backup changeover
data synchronization
PLC
fault of network
