01 November 2002
Simulation data sources
Configuration and real-time values arrive from three sources. The MPC configuration tool (model editor) is the application that identifies, verifies, and modifies multivariable process models. Based on these models, the model editor automatically generates matching MPC controller matrices.
The MPC simulator is a separate application that launches from the MPC model editor. The three types of information that respond to a simulation request include the following:
The current control project, mathematical I/O relations represented as a step response model
General control loop configuration such as physical meanings of I/O and engineering units
Actual process values from the real process
The currently modified project information emanates from the configuration tool (model editor). It contains mathematical process models for the MPC controller and MPC process simulator blocks, as well as a controller matrix that matches the controller model.
More general configuration settings that determine where and how the MPC control loop will apply pull from the common process system database. To find initial starting conditions for the multivariable simulation, the simulator application tries to retrieve actual process data.
If the status of the field data is good, the system uses the values. Otherwise, averaged values of process variables that stored during the identification procedure will serve as starting conditions for simulation.
This design ensures a good representation of the application of all configuration settings to the current process at its normal range of operation. At the same time, the simulation is flexible and easy to use for model iterations.