You can estimate the frequency response of one or more blocks in a stable Simulink® model at steady state.
Your model can contain any Simulink blocks, including blocks with event-based dynamics. Examples of blocks with event-based dynamics include Stateflow® charts, triggered subsystems, pulse width modulation (PWM) signals.
You should disable the following types of blocks before estimation:
Blocks that simulate random disturbances (noise).
For alternatives ways to model systems with noise, see Estimating Frequency Response Models with Noise Using Signal Processing Toolbox.
Source blocks that generate time-varying outputs that interfere with the estimation. See Effects of Time-Varying Source Blocks on Frequency Response Estimation.