The Research On Supervisory Control And Data Acquisition System Reliability In Shengli Chengdao Oilfield Offshore Platforms

Generally there are two methods to enhance reliability of the SCADA(Supervisory Control and Data Acquisition) system, improving component parts of the system or applying redundant technology. However, it is very difficult to enhance reliability of the system by the first method, theoretic analysis indicates that the second method is more effective.Firstly, the scheme of double-computer hot-backup is designed and programmed. And double-computer redundancy is realized and applied in the SCADA system of Chengdao oilfield. Secondly, to resolve the problem of Chengdao oilfield communication system, the scheme of redundant technology is designed. The scheme is considered from solving the communication interruption caused by equipments failure and single frequency band disturbance. At last, the thesis analyzes CPU redundant technology of PLC system and designs schemes of CPU hardware redundancy and CPU software redundancy. The CPU software redundancy is realized by programming and applied in Chengdao oilfield. The result of application indicates that the scheme of CPU software redundancy is more economical and effective than the scheme of CPU hardware redundancy.The partial application of the SCADA system redundant technology in Chengdao oilfield demonstrates that the technology can enhance the reliability of the system.