Siemens SINAMICS G130 - Slip Compensation

Setpoint channel and closed-loop control
7.3 V/f control
Inverter chassis units
Operating Instructions, 07/2016, A5E00331449A
335
Note
Automatic setting
When p1349 = 0, the changeover limit is automatically set to 95% of the rated motor
frequen
cy, but only up to 45 Hz.
Function diagram
FP 6310
Resonance damping and slip compensation
Parameters
•
r0066
Output frequency
•
r0078
torque
-generating actual current value
•
p1338
U/f control resonance damping gain
•
p1339
U/f control resonance damping
filter time constant
•
p1349
U/f control resonance damping maximum frequency
7.3.3
Slip compensation
Description
Slip compensation essentially keeps the speed of induction motors constant irrespective of
the load (M
1
or M
2
).
When the load is increased from M
1
to M
2
, the setpoint frequency is increased automatically
so that the resulting frequency and thus also the motor speed remain constant. For a
decrease in the load from M
2
to M
1
, the setpoint frequency is automatically decreased
accordingly.
For p1300 = 4 and 7 (U/f controllers with ECO), the slip compensation must be activated to
ensure correct operation.
For p1300 = 5 and 6 (textiles) the slip compensation is internally disabled in order to be able
to precisely set the output frequency.
If a motor holding brake is applied, a setting value can be specified at the slip compensation
output via p1351. If parameter p1351 > 0 then the slip compensation is switched on
automatically (p1335 = 100%).