Siemens SINAMICS S120 Function Manual page 273

1. Undervoltage in the DC link
2. Overvoltage in the DC link
Properties
● V
● V
● V
Drive functions
Function Manual, (FH1), 04/2014, 6SL3097-4AB00-0BP4
– Typical cause:
Failure of the supply voltage or supply for the DC link.
– Remedy:
Specify a regenerative torque for the rotating drive to compensate the existing losses,
thereby stabilizing the voltage in the DC link (kinetic buffering).
– Typical cause:
The drive is operating in regenerative mode and is supplying too much energy to the
DC link.
– Remedy:
Reduce the regenerative torque to maintain the DC-link voltage within permissible
limits.
control
dc
– This comprises V
dc_max
functions can be parameterized independently of one another and activated.
– There is a common PID controller. The dynamic factor is used to set V
control to a smoother or harder setting independently of each other.
control (kinetic buffering)
dc_min
– With this function, the kinetic energy of the motor is used for buffering the DC-link
voltage in the event of a momentary power failure, thereby delaying the drive.
control
dc_max
– This function can be used to control momentary regenerative load without shutdown
using "overvoltage in the DC link".
– V control is only recommended with a supply without active closed-loop control
dc_max
for the DC link and without feedback.
control and V control (kinetic buffering). These two
dc_min
U/f control (vector control)
6.4 Vdc control
and V
dc_min dc_max
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