Automated Control Of Gas Pipeline Systems With Added Input of a Planned Production Schedule
Publication Date: 2007-Mar-30
The IP.com Prior Art Database
An automated gas pipeline control method that augments typical reactive techniques, such as model predictive or fuzzy logic, with the input of a planned production schedule.
Continuously matching gas production with customer pipeline demand flow is critical to reducing product losses (venting of gas and vaporization of liquid back-up). This is very challenging because customer demands are generally unsteady, gas production plants are restricted with regard to both operating range and modulation rate, products other than pipeline gas are also required, process equipment availability varies, and variable power costs exist. Because of the constant attention required for such an operation, manual control is not effective. Prior automated methods have improved production response to unexpected changes in customer demand. Such methods do not include planned or anticipated changes in either customer demands or operating constraints. These planned or anticipated changes are known by plant personnel through communications with pipeline customers and/or power suppliers and production equipment outage schedules. Failure to incorporate this information into any automated pipeline control system results in unnecessary product loss due to the delayed production changes performed by the reactive automation.
In accordance with the present development,an automated gas pipeline control method is provided that augments typical reactive techniques, such as model predictive or fuzzy logic, with the input of a planned production schedule. The pipeline system could include a single or multiple producing units and unlimited customers. This input could be compiled (hours before actual changes occur) by operating personnel on an hourly, daily or weekly basis and/or transmitted directly from the customers and power suppliers. The input, can include, but is not limited to forecast of customer gas demands, site energy costs, required rates of non-pipeline products, and equipment availability. This way pipeline product loss is reduced by the addition of a planned production schedule as an input to an advanced process control system. The schedule is used to calculate optimum production target(s) at the forecast conditions and then adjust production rate(s) to achieve the optimum target(s) in a more timely and optimized manner. This method could be supplemented by more conventional feedback (i.e., reactive) control components.
The added input of a planned production schedule to any reactive control system allows optimum production to be reached before actual changes in operating requirements (e.g., customer demand, supplier power costs, and equipment constraints) are detected. Instead of using measurements of what is occurring or has already occurred, this method uses a combination of the planned production values and actual current measurements. This provides more time...