安全级数字化仪控系统优先级逻辑模块的分析

Analysis on 1E Digital Control System Priority Logic Module

安全级数字化仪控系统(Digital Control System, DCS)优先级逻辑模块是核反应堆仪控系统重要的组成部分之一,其主要功能是针对不同的DCS控制命令进行优先级判断,然后驱动专设安全设施及支持系统的泵、阀等相关设备.文中对国内3种优先级逻辑模块进行了介绍,通过分析不同优先级逻辑模块的实现方式与功能,对比其特点与优势.结果表明NASPIC的ACM模块在防止软件共因故障方面表现更为优异.这种纯硬件结构不仅能降低模块响应的时间,还能有效地避免软件共因故障,但这也导致了其能够实现的功能相对有限.Firmsys平台CIM的功能更为复杂.CIM中既含有MCU又含有CPLD,能够对设备实现分类化、精细化控制.NASPIC的PLM是完全基于CPLD建立起来的,PLM可以实现的功能相对丰富,为了避免软件共因故障,PLM中没有设计微处理器结构.目前,国内外基于自身理念设计的不同优先级逻辑模块的相关文献十分有限,因此,本文具有重要的工程意义与参考价值.

The nuclear reactor 1E digital control system(DCS)priority logic module is one of the very important components of the nuclear reactor instrument and control(I&C)system.Its main function is to prioritize different DCS control command,and then drive especial safety facilities and related support systems(pumps,valves and other related equipment).The characteristics and advantages among the three kinds of domestic priority logic modules are analyzed by comparing their function and implementation modes.The results showed that ACM of NASPIC was more prominent from the perspective of preventing software common cause failure(SWCCF).The pure hardwired structure could not only reduce the module response time,but also prevent the SWCCF.However ACM’s function is relatively limited due to its pure hardwired structure.The structure of Firmsys’s CIM is more complicated in contrast to that of ACM.CIM contains both MCU and CPLD,and can achieve classified and sophisticated control.NASPIC’s PLM is totally established based on CPLD,and the function of PLM is relatively rich.Moreover,to avoid the SWCCF,there is no microprocessor in the PLM.At present,many companies at home and abroad have designed different priority logic modules based on their own ideas.However,the public literature about priority logic modules is very limited.Therefore,this paper has important engineering significance and reference value for the design of priority logic module.