Simulink Control Design™ - MathWorks

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Cannot Find Acceptable PID Design in Simulated Model


When you run your Simulink model using the PID gains computed by PID Tuner, the
simulation output may not meet your design requirements.

How to Fix It


Sometimes, PID control is not adequate to meet the control requirements for your plant.
If you cannot find a design that meets your requirements when you simulate your model,
consider designing a more complex controller using Control System Designer.

If you have enabled saturation limits in the PID Controller block without antiwindup
circuitry, enable antiwindup circuitry. You can enable antiwindup circuitry in two ways:


  • Activate the PID Controller block antiwindup circuitry on the PID Advanced tab of
    the block dialog box.

  • Use the PID Controller block tracking mode to implement your own antiwindup
    circuitry external to the block. Activate the PID Controller block tracking mode on the
    PID Advanced tab of the block dialog box.


To learn more about both ways of implementing antiwindup circuitry, see “Anti-Windup
Control Using a PID Controller” (Simulink).

After enabling antiwindup circuitry, run the simulation again to see whether controller
performance is acceptable.

If the loop response is still unacceptable, try slowing the response of the PID controller.
To do so, reduce the response time or the bandwidth in PID Tuner. See “Refine the
Design” on page 7-16.

You can also try implementing gain-scheduled PID control to help account for
nonlinearities in your system. See “Design Family of PID Controllers for Multiple
Operating Points” on page 7-192 and “Implement Gain-Scheduled PID Controllers” on
page 7-201.

If you still cannot get acceptable performance with PID control, consider using a more
complex controller. See Control System Designer.

Cannot Find Acceptable PID Design in Simulated Model
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