User`s guide

modred
11-145
Next, the derivative of is set to zero and the resulting equation is solved for
. T he reduced-order model is given by
The discrete-time case is treated similarly by setting
Limitations With the ma tched DC gain method, must be inv ertible in continuous time,
and must be invertible in discrete time.
See Also balreal Input/output balancing of state-space models
minreal Minimal st ate-space realizations
x
·
1
x
·
2
A
11
A
12
A
21
A
22
x
1
x
2
B
1
B
2
u+=
y
C
1
C
2
xDu+=
x
2
x
1
x
·
1
A
11
A
12
A
22
1
–
A
21
–[]x
1
B
1
A
12
A
22
1
–
B
2
–[]u+=
yC
1
C
2
A
22
1–
A
21
–[]xDC
2
A
22
1–
B
2
–[]u+=
x
2
n1
+[]
x
2
n
[]=
A
22
IA
22
–