Simulink Control Design™ - MathWorks

• The [0.005 0.006] second range where the converter reacts to the current load being
  removed.

The blue curve shows the complete plant response that contains the contributions from

the initial transients (significant for times < 0.001 seconds), the response to the cyclic

current load (time durations 0.0025 to 0.005 seconds), reference voltage change (at 0.004

seconds), and response to the step test signal (applied at time 0.003 seconds). In contrast,

the red curve is the response to only the initial transients, reference voltage step, and

cyclic current load.

The green curve is the data that will be used for plant identification. This curve is the

change in response due to the step test signal, which is the difference between the blue

(input response) and red (offset response) curves taking into account the negative

feedback sign.

To use the measured data to identify a plant model, click Apply. Then, to return to plant

identification, click Close.

Plant Identification

PID Tuner identifies a plant model using the data generated by simulating the model.

You tune the identified plant parameters so that the identified plant response, when

provided the measured input, matches the measured output.

7 PID Controller Tuning