Siemens SINUMERIK 840D Description Of Functions page 72

3 Start-Up
3.9 Fine adjustment and optimization
3-72
SINUMERIK 840D/SIMODRIVE 611 digital Descr. of Functions HLA Module (FBHLA) – 04.00 Edition
3. f >> f (f )

valve cylinder
The valve can actively influence all natural frequencies of the drive.
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. 3-24 Frequency response of controlled system (
The controller components are optimized in the following order:
1. P component (proportional component)
2. D component (derivative component)
3. I component (integral component)
The preferred method of optimization uses unit step functions (step response)
with the function generator (FG) through the input of a velocity setpoint v
The measuring function with noise signals (FFT, PBRS) may be difficult to inter-
pret owing to non-linearities in the controlled system.
The causes for deviations in the characteristic data are as follows:
S
Theor. Valve: Real valve
S
Pipework: Control pressure = f(Q)
S
Additional valves; Shutoff valves; filters; throttles (pressure measuring
plates)
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=20 Hz; Da=0.1
>> f
)
cylinder
.
set