Simulink Control Design™ - MathWorks

(Tuis.) #1
In an open-loop configuration, you can connect this input port to a source that drives your
plant to the desired operating point for estimation. For instance, you can use a Constant
block set to an appropriate value.
Data Types: single | double

y — Plant output
scalar

Connect this port to the plant output.
Data Types: single | double

start/stop — Start and stop the estimation experiment
scalar

To start and stop the estimation process, provide a signal at the start/stop port. When
the value of the signal changes from:


  • Negative or zero to positive, the experiment starts

  • Positive to negative or zero, the experiment stops


Typically, you can use a signal that changes from 0 to 1 to start the experiment, and from
1 to 0 to stop it. When the experiment is not running, the block adds no perturbation at
the u + Δu or Δu port. In this state, the block has no impact on plant behavior.

Start the experiment when the plant is at the desired equilibrium operating point. In a
closed-loop configuration, use the controller to drive the plant to the operating point. In
an open-loop configuration, you can use a source block connected to u to drive the plant
to the operating point.

Let the experiment run long enough for the algorithm to collect sufficient data for a good
estimate at all frequencies it probes. The block displays a recommended experiment
length in the Experiment Length section of the block parameters. This value is based on
the experiment mode and the frequencies you specify for the experiment.


  • When Experiment mode is Sinestream, the recommended experiment length is:



i

2 π
ωi
Nset,i+Nestim,i +2TsNfreq,

where:

16 Blocks — Alphabetical List

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