Setting The Current Controller Loop - Siemens SIMOTRAS 6SG7050 Operating Instructions Manual

01.04
7.6.8

Setting the current controller loop

Formula:
The factory setting for the current controller parameter can normally be left as it is:
P155 = Kp = 0.2 P156 = Tn = 20 ms
Optimizing the current controller:
With the motor fully braked, enter the current setpoint increments and record the step response
from the current controller loop.
Rotor stage S1 is active
• Fully brake the motor and interrupt the supply voltage to the brake contactor.
• P084 = 2 (current-controlled operation)
current setpoint from square wave generator (P500 = 203, factory setting)
• Parameterize square wave generator:
P480 = 20,0 % (step level 1)
P481 = 1.0 s (duration of step)
P482 = 10.0 % (step level 2)
P483 = 1.0 s (duration of step)
• Enter first setpoint stage from master switch (i.e. a travel command).
• Trace the stator current on the actual current value output (X175 terminals 12 and 13, 5V is the
rated current for the SIMOTRAS HD) using an oscilloscope. The oscillogram will display the step
response of the current controller loop.
Current setpoint
Actual current value
• The following settings affect the current controller loop:
P155 Controller gain Kp
P156 Reset time Tn
The control response becomes "softer" if a longer reset time is set.
• Move master switch to zero position (i.e. cancel travel command).
• Following current controller optimization:
P084 = 1 (reset to operation under closed-loop speed control)
• Reconnect power supply to brake contactor.
SIEMENS AG 6SG7000-0BA76
SIMOTRAS HD Operating Instructions
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Start-up
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