安全仪表系统(SIS)后备冗余技术叠加双环冗余技术的研究与应用

Research and Application of Backup Redundancy Technology for Safety Instrumented Systems(SIS)Combined with Dual Loop Redundancy Technology

某LNG接收站DCS/SIS系统投用两年以来多次发生系统故障引发现场联锁,造成装置停车、生产波动。由于该接收站DCS/SIS系统通讯共用一个环网,整个网络架构采用单环网冗余结构,SIS系统安全通讯未完全独立。当网络架构中一个环节出现问题时,两个系统同时失效,SIS系统安全功能得不到有效发挥。本研究对系统进行重构后,将SIS系统安全通讯部分单独剥离,环网内部具有后备冗余自动切换的能力,同时外部形成内外双环网冗余。该系统的优化弥补了DCS/SIS系统共用环网在使用中遇到的各种缺陷,解决了该LNG接收站联锁保护系统不稳定的重大难题。

Since the DCS/SIS system of a certain LNG receiving station was put into operation for two years,there have been multiple system failures that have caused on-site interlocking,resulting in device shutdown and production fluctuations.Because the DCS/SIS system communication at the receiving station shares a ring network,the entire network architecture adopts a single ring network redundancy structure,and the SIS system's secure communication is not completely independent.When a problem occurs in one link of the network architecture,both systems fail simultaneously,and the security function of the SIS system cannot be effectively utilized.After the system was restructured in this study,the security communication part of the SIS system was separated,and the internal ring network had the ability to automatically switch backup redundancy.At the same time,external dual ring network redundancyywas formed.The optimization of this system has made up for various defects encountered in the use of the shared ring network of the DCS/SIS system,and solved the major problem of instability in the interlocking protection system of the LNG receiving station.