Research On Safety Evaluation Method Of Oil And Gas Gathering And Transmission SCADA System

SCADA system of oil-gas gathering and transporting, as the core of oil and gas field industrial control system, plays a very important role in long-distance supervisory control and management of oil production, metering and transferring. SCADA was previously a closed and isolated system, with strong access control. With the development of computer network and communication technology, SCADA has been improved to be relatively open, but leading to obvious safety problems. Safety of SCADA has a bearing on the industrial progress and high-speed development of national economy, which receives increasing attention. Safety assessment of SCADA is a effective approach to analyze the safety level and prevent safety risk, which will increase safety of the system.A method of safety assessment applicable for SCADA system is studied in this paper. On the basis of comprehensive analysis on structure of SCADA and potential safety problems, traditional fuzzy comprehensive assessment of safety assessment is combined with artificial intelligence expert system to design the model of SCADA safety assessment expert system, making achievements in the development and design of knowledge base, inference engine, human-computer interface and prototype system of safety assessment expert system.The design of knowledge base mainly applies for analytic hierarchy process to establish safety assessment index system of SCADA and determine index weights by inter-comparison of indexes. Inference engine of expert system mainly applies for fuzzy comprehensive assessment to achieve the design of three inference structures including index level, criterion level and target level. The design of human-computer interaction interface functions as a bridge between expert system and users, which provides convenience for information input and output.The test of safety assessment expert system of SCADA is achieved to prove it be reasonable after the input of 4 sets of representative test data, the application of weight and membership grade knowledge of knowledge base and the inference and calculation in inference engine.and combining the examples, this expert system is applied test to be proved feasible.