Siemens SIMODRIVE 611 universal Function Manual page 378

6 Description of the Functions
6.2 Positioning mode (P0700 = 3, from SW 2.1)
Position
loop gain
(Kv factor)
P0200:8
P0031
Table 6-24 Parameters for the position loop gain
No. Name
0200:8 Kv factor (position loop gain)
The Kv factor defines at which traversing velocity of the axis which following error is obtained.
Low Kv factor:
High Kv factor:
Examples:
= 0.5
= 1 is obtained
= 2 is obtained
Note:
The following parameters are available for position loop gain diagnostics:
S
P0029
S
P0030
S
P0031
Refer under the index entry "Diagnostics of the motion status"
6-378
The position loop gain (Kv factor) defines which following error is obtai-
ned at which axis traversing velocity.
The mathematical (proportional) equation is as follows:
Velocity v
Kv factor=
Following error ns
The K factor influences the following important characteristic quantities
v
of the axis:
S
Positioning accuracy and holding control
S
Uniformity of the motion
S
Positioning time
The better the axis design (high degree of stiffness), then the higher is
the achievable K factor, and therefore the better the axis parameters
v
from the technological perspective (lower following error).
Note
The stable position loop gain which can actually be set for the
complete position control loop is influenced by time constants as well
as backlash (play) and spring elements in the control loop.
The required Kv factor is entered in P0200:8.
The actual (measured) Kv factor is displayed in P0031.
0.0
Slow response to setpoint–actual value difference ns is high
Fast response to setpoint–actual value difference, ns is small
Kv factor Significance
at v = 1 m/min an ns of 2 mm
at v = 1 m/min an ns of 1 mm
at v = 1 m/min an ns of 0.5 mm is obtained
Following error
System deviation, position controller input
Actual Kv factor (position loop gain)
SIMODRIVE 611 universal Description of Functions (FBU) – 04.05 Edition
[1000/min]
Min. Stan- Max.
dard
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