National Instruments 370757C-01 ユーザーズマニュアル

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Chapter 4
Controller Synthesis
4-18
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  -0.500025 + 0.866011 j
  -0.500025 - 0.866011 j
5.
Try the LQG compensator with the full-order system:
[Syscl_fo]=feedback(Sys,Sysc);
poles(Syscl_fo)
ans (a column vector) =
  -0.401519  + 0.864869 j
  -0.401519  - 0.864869 j
  -0.638796  + 0.855861 j
  -0.638796  - 0.855861 j
   0.0152647 + 4.90994  j
   0.0152647 - 4.90994  j
6.
Find a stabilizing reduced order controller using frequency shaping.
To stabilize this system, try a frequency-shaped control-law, where the 
weighting on the control signal will be 1 + (
ω)
4
.
First, form an augmented system, defining two additional states, 
μ and
The augmented system will be:
(4-3)
(4-4)
Note
The augmented system has two extra states implementing the frequency shaping on 
the control system. 
aa=[ar,br,[0;0];0,0,0,1;0,0,0,0];
bb=[0,0,0,1]';cc=[0,0,1,0];dd=0;
Sysa=system(aa,bb,cc,dd)
Sysa (a state space system) =
  A
   0     1       0    0
  -1    -0.01    1    0
u·.
d
dt
-----
x
r
u
u
·
A
r
B
r
0
0
0 0 0 1
0 0 0 0
x
r
u
u
·
0
0
0
1
v
+
A
a
x
A
B
a
v
+
=
=
u
0 0 1 0
x
r
u
u
·
0
( )v
+
C
a
x
A
D
a
v
+
=
=