Environmental Engineering Reference
In-Depth Information
90
W
11
(s)
W
12
(s)
W
2
(s)
80
70
60
50
40
30
20
10
0
10
-3
10
-2
10
-1
10
0
10
1
10
2
Frequency (Hz)
Fig. 5.7
Weight functions in the design of the generator torque H
?
control
From: a
Tss
(m/s
2
)
From: w
g
(rad/s)
70
90
60
80
50
40
70
30
60
20
10
50
10
0
10
0
Frequency (Hz)
Frequency (Hz)
Fig. 5.8
Bode diagram of the generator torque H
?
control
in the tower first fore-aft mode. Some notch filters are included in the pitch
controller dynamics to reduce the excitation in some frequencies in the open loop
response. The H
?
Pitch Controller has two inputs (generator speed w
g
and tower
top fore-aft acceleration a
Tfa
) and one output (collective pitch angle b
H?
).
The selected nominal plant to design the controller is the linealized plant at the
19 m/s wind speed operational point. The nominal plant has one input: collective
pitch angle and two outputs: generator speed and tower top fore-aft acceleration.
