Controller Optimization - Siemens SINUMERIK 840D Description Of Functions

3 Start-Up
3.9 Fine adjustment and optimization
3.9.5

Controller optimization

General
3-70
SINUMERIK 840D/SIMODRIVE 611 digital Descr. of Functions HLA Module (FBHLA) – 04.00 Edition
The most important travel motions are converted via the feedforward control
path.
The function of the controller parameters is to dampen the oscillation character-
istics of the valve/cylinder grouping.
In this respect, three different scenarios relating to the corner frequency (f) must
be distinguished:
1. f << f (f )


valve cylinder
The valve cannot actively influence any cylinder frequency that is higher
than the valve corner frequency.
Disturbances with frequencies f
Amplitude log frequency curve
1
10
0
10
–1
10
–2
10
–3
10
–4
10
–5
10
1
10
Phase frequency curve
–90
–180
–270
1
10
Fig. 3-22 Frequency response of controlled system (
> f cannot be dampened.
St valve
2 3
10 10
log f
2 3
10 10
log f
f
valve
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02.99
Valve:
fv=100 Hz; Dv=0.8
Drive:
fa=500 Hz; Da=0.1
<< f
)
cylinder