User`s guide

3 Linear Model Identification
Typically, you specify the model-structure acronym as a string argument in
the estimation c ommand
pem:
•
pem(data,'P1D') to estimate the following structure:
Gs
K
sT
e
p
sT
d
()=
+
−
1
1
• pem(data ,'P2ZU') to estimate the following structure:
Gs
KsT
sT sT
pz
ww
()=
+
()
++
1
12
22
ζ
• pem(data ,'P0ID') to estimate the following structure:
Gs
K
s
e
p
sT
d
()=
−
• pem(data ,'P3Z') to es timate the following structure:
Gs
KsT
sT sT sT
pz
ppp
()=
+
()
+
()
+
()
+
()
1
111
123
For m ore information about estimating models , see “Estimating Process
Models at the Command Line” on page 3-29.
Options for Multiple-Input Models
If your model contains multiple inputs, you can specify whether to estimate
the same transfer function for all i np uts, or a different transfer function
for each input. The information in this section supports the estimation
procedures “How to Estimate Process Models Using the GUI” on page 3-23
and “Estimating Process Models at the Command Line” on page 3-29.
In the System Identification Tool GUI. To fit a data set with multiple
inputs in the Process Models dialog box, configure the process m odel settings
foroneinputatatime. Whenyoufinish configuring the model and the
3-36