Specifications

Design Controller Using the Design Tool
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it. Left-click in a graph's white space to erase its markers. For more information on data
markers, see the Control System Toolbox documentation.
Open-Loop Simulations
By default, scenarios are closed loop, i.e., an active controller adjusts the manipulated
variables entering your plant based on feedback from the plant outputs. You can also run
open-loop simulations that test the plant model without feedback control.
For example, you might want to check your plant model's response to a particular input
without opening another tool. You might also want to display unmeasured disturbance
signals before using them in a closed-loop simulation.
To see how this works, create a new scenario by right-clicking the TSetpoint node
in the tree, and selecting Copy Scenario in the resulting menu. Rename the copy
OpenLoop.
Select OpenLoop in the tree. On its scenario view, change Duration to 100, and turn off
(clear) Close loops.
Open-loop simulations ignore the Setpoints table settings, so there is no need to modify
them.
If CSTR had a measured disturbance input, the pane would contain another table
allowing you to specify it.
For this example, focus on the Unmeasured disturbances table. Configure it as shown
below.
The C_A_i input's nominal value is 0.0 (see Model Predictive Control Toolbox Design
Tool's Signal Definition View), so the above models a sudden increase to 1 at the
beginning of the simulation. The following is an equivalent setup using the Step type.