Siemens SINAMICS SM150, Operating And Installation Instructions

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8.4.3.5 Vdc-max closed-loop control
The Vdc-max controller is not usually required, because the braking energy of the active infeed
is fed back into the power system. The VDC closed-loop control can increase the ruggedness
of the drive when power outages are expected or the medium-voltage power system cannot
safely absorb the braking energy.
For this purpose, the vdc-max closed-loop control must be parameterized to an activation level
above the setpoint of the Active Line Module. If a supply system fault occurs during a braking
action, the drive does not shutdown for overvoltage. The drive continues to brake with the
largest torque possible for the supply system characteristics and the internal losses.
Adjustable parameters
Parameter Function Adjustment range
p1240 Vdc_controller configuration 0 ... 3
Factory setting: 1
Setting for the controller configuration for the voltage DC link (vdc controller).
Values:
0: Inhib Vdc ctrl
1: Enable vdc-max controller
The vdc-max controller increases the ramp-down times automatically to keep the DC link voltage within the permissible limits.
Parameter Function Unit
p1242 Vdc_max_controller switch-on level V
Display of the switch-on level of the vdc-max controller.
Parameter Function Adjustment range
p1243 Vdc_max_controller dynamic factor 10 ... 200 %
Factory setting: 100 %
Setting for the dynamic factor of the vdc-max controller.
100% means that the following parameters are used in accordance with their initial settings. The use is based on a theoretical
controller optimization.
● p1250, gain
● p1251, settling time
● p1252, derivative-action time
If subsequent optimization is required, this can be set using the dynamic factor. In this case p1250, p1251, p1252 parameters
are weighted with the dynamic factor p1243.
Parameter Function Adjustment range
p1250 Vdc_controller proportional gain 0.00 ... 10.00
Factory setting: 1.00
Display of the switch-on level of the vdc-max controller.
Operation
8.4 Functions
SINAMICS SM150 6SL3845-7NN46-7AA0
Operating Instructions 04/2017
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