This paper examines the application of an Expert System Language to pipeline simulation and data integrity. The paper describes:
What an Expert System is and how Tennessee Gas Pipeline implemented its application.
How the Expert System provides Controllers, Engineers and Planners with near real-time information and recommendations to operate the pipeline more efficiently.
Real-world examples of the Controllers' knowledge, embedded in the program, and how the knowledge is applied in the operating environment.
Methodologies for checking data programmatically and correcting it if it is anomalous.
An introduction to the logical arrangement of objects to represent a pipeline and its components to maximize the users' ability to infer information from the data presented.
How the Expert System could be used to "glue" together traditional SCADA systems and Pipeline Simulators.
This paper explores the thought process that was considered in implementing an Expert System. The topics covered will include: a brief background of Tennessee Gas Pipeline, the definition of an Expert System in the context of this paper, the hardware, software and resource requirements for implementing an Expert System, who could benefit from an Expert System as well as a brief discussion on how returns are measured. Furthermore this paper examines ways of combining the strengths of Expert Systems and pipeline simulators to enhance the accuracy of both applications which could lead to more profitable pipeline operations. Although this paper references a vendor's language, the author believes that the concepts are similar in most Expert System Languages.
In 1995 Tennessee Gas Pipeline began researching the benefits that a pipeline could realize using an Expert System. The original intent of the Expert System was fuel minimization. As the project evolved the programmers realized that only imagination, time and money limited the expert application. Consequently, consistency in operation, improved reliability and safety were placed on an equal footing with efficiency and coding progressed rapidly. As with all simulation systems, data integrity became a critical issue. The Tennessee Gas Controllers and Engineers developed several techniques for resolving inconsistent data and replacing the erroneous data with reasonable values "on-the-fly".
Tennessee Gas is owned by El Paso Energy the nation's only coast-to-coast natural gas pipeline. Tennessee Gas Pipeline Company operates three separate wholly owned interstate pipeline systems—East Tennessee Natural Gas, Midwestern Gas Transmission and Tennessee Gas Pipeline,. The Tennessee system serves natural gas markets in 20 states, principally in the Northeast and Midwest. Tennessee Gas supervises all of the pipelines (approximately 16,000 miles of pipe and over 70 compressor stations consisting of 1.5 million horsepower) from a single control center located northwest of Houston.