Natural Frequency Of Hydraulic Drive - Siemens SINUMERIK 840D Description Of Functions

2 Configuring
2.3 Configuring the hydraulic drive
Table 2-12 Shutoff valves
Bosch Nominal
order number size
0 811 004 103 Size 6
0 811 004 104 Size 6
0 811 024 122 Size 6
0 811 024 121 Size 6
2.3.4

Natural frequency of hydraulic drive

Servo gain
2-42
SINUMERIK 840D/SIMODRIVE 611 digital Descr. of Functions HLA Module (FBHLA) – 04.00 Edition
b
B T
' '
B T
a
P
'
P
The implementable servo gain is essentially determined by the natural fre-
quency of the cylinder and its load ω
solenoid valve ω
.
v
The cylinder and its load constitute a spring/mass system whose natural fre-
quency is calculated according to the following formula:
4 @ E @ A
ω X
o
m @ h
The letters have the
following meaning:
Oil volumes in the cylinder pipes must also be taken into account.
The minimum natural frequency occurs only at a particular mid-position and
increases as the end positions are approached.
The calculation is made by means of the "HYDRO 2" program.
Graphic symbol
A T B' P'
' '
A T B P
A' P'
a
A P
A B T' P'
' '
b
A B T P
A B' T'
'
A B T
and the limit frequency of the servo
0
A
1 + α
( )
2
E=Modulus of elasticity 1,1 @ 10
A=Piston area (m
A =Ring surface(m
R
h=Stroke (m)
α=Surface ratio A
m=Mass (kg)
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02.99
Bosch
catalog
A
R
m
h
9 2
(N/m )
2
)
2
)
/A
R