The block provides a recommended experiment length in the Experiment Length section
of the block parameters. Typically, you configure the start/stop signal such that there is at
least that much time between the rising and falling signals. In a deployed environment
when you are setting estimation parameters at run time, you must be aware of how
experiment parameters such as estimation frequencies affect the required experiment
length. For more information about determining the appropriate length, see the
Frequency Response Estimator block reference page.Step 3. Set Experiment Parameters
The frequency-response estimation experiment injects sinusoidal signals at the
frequencies you specify with the Frequencies parameter (or at the w port) of the
Frequency Response Estimation block. Specify the perturbation amplitudes using the
Amplitudes parameter (or at the amp port.The block can apply the perturbation at each frequency separately (sinestream mode) or
simultaneously (superposition mode). To specify which mode to use, set the Experiment
mode parameter.- Sinestream mode — Applies the perturbation one frequency at a time. Sinestream
mode can be more accurate and can accommodate a wider range of frequencies than
superposition mode. - Superposition — Applies the perturbation as a superposition signal containing all
frequencies at once. The estimation experiment is generally faster in superposition
mode.
You can also specify parameters that tell the block how to long to let the system settle
when the perturbation is applied, and how long to measure the response for the
estimation. For further details about the two signal types and their relative advantages,
see the Experiment mode parameter description on the Frequency Response Estimator
block reference page.Step 4. Run Experiment
After you deploy the estimation module to your system, use a rising start/stop signal to
begin the estimation experiment. The deployed module injects the test signals into your
physical plant in real time. After an appropriate time, your falling start/stop signal
ends the experiment. (For more information about determining the appropriate length,
see the Frequency Response Estimator block reference page.)6 Online Frequency Response Estimation