Multivariable Controller - Variable Limits Window
This window is used to set maximum and/or minimum value, an iteration step size, and specify a value for the second iteration for each control variable. A formula may also be entered to scale the variable.
Multivariable Controller Variable Parameter Specifications
Each control variable will be allowed to change between the minimum and maximum limits entered here. On each iteration, PRO/II will change the control variables automatically. If you want to limit the size of that change, you can enter the maximum change per iteration (maximum step size) in the appropriate entry field.
Variable Value for Second Iteration
The default step size for the second iteration of the Multivariable Controller is to change each variable by ten percent. However, you can request PRO/II to change the variable by a different percent or by a specified amount for the second iteration. For further iterations, PRO/II will determine the best step size, but it will not make the step size greater than the limit you set for the maximum change.
Variable Scaling
You may enter a formula for scaling any control variable. The same initial value, step sizes and tolerances are applied to all scaled variables in the Multivariable Controller. For information on changing these values, see the Multivariable Controller - Options Window.
Continuing Calculations if Variable Exceeds Limits
If any variable exceeds its specified minimum or maximum value, by default, the simulation will continue calculations and the limiting value will be used in the calculations.
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