Simulink Control Design™ - MathWorks

• External ports — Select to enable the w and amp input ports. Use this option if you
  want to change the frequencies and amplitudes of the perturbation signal after
  deployment.

Programmatic Use

Block Parameter: SineSource

Type: character vector, string

Values: 'Block parameters' | 'External ports'

Default: 'Block parameters'

Frequencies — Frequencies for estimation

[0.5 1 2] (default) | vector

Frequencies at which to estimate the frequency response of the plant. The block injects a

perturbation at each of these frequencies, either simultaneously (when Experiment

mode is Superposition) or sequentially (Experiment mode is Sinestream). The

highest frequency you can estimate is limited by the Nyquist frequency, π/Ts rad/s, where

Ts is the value you set for the Sample time (Ts) parameter.

When Experiment mode is Superposition:

• To maintain reasonable convergence speed and estimation accuracy, it is typical to use
  about 20–30 frequencies for estimation. The best practice is to specify no more than
  about 50 frequencies.


• The best practice is to limit the range between the lowest and highest frequency to no
  more than about two decades. This limit reduces the chance that the responses of
  some frequencies are so dominant that they hurt the estimation of responses at other
  frequencies.


• Attempting to linearize a model containing a Frequency Response Estimator block
  using superposition mode and more than 50 frequencies can generate an error. The
  error states "The model contains too many elements for linearization. Please reduce
  the model size." To complete linearization, you must either comment out the
  frequency-response estimator block or reduce the number of frequencies.

When Experiment mode is Sinestream, there is no recommended limit on the number

or range of frequencies. However, due to the sequential nature of the sinestream

perturbation, each frequency point you add increases the required experiment time (see

the start/stop input port for details). Further, a too-wide range of frequencies requires

you to use a fast sample time for high frequencies that is inefficient for the lower

frequencies.

16 Blocks — Alphabetical List