Siemens sinamics dcp - 7.11.10 Current control

Operation
7.11 Closed-loop control
SINAMICS DCP
Operating Instructions, 09/2019, A5E34382853K
345
The voltage correction controller can be activated on one or both sides of the DCP. This is
configured using parameter p54155.
It is then enabled depending on the actual voltage controlled side (r54106.0, r54106.1) and
the setting of p54155.
For each DCP side, an external voltage actual value can be read-in via BICO inputs
(p54151, p54152); the switchover is then realized dependent on the actual voltage-controlled
side of the DCP (r54106.0, r54106.1).
External voltage actual values can be fed in via analog inputs of the CUD or via digital field
buses.
The deviation between external and internal voltage actual value is monitored, assuming that
the voltage correction controller is active.
If the maximum tolerated deviation (p54162) is exceeded, then fault message F60512 is
output.
The fact that the internal voltage controller and the internal voltage sensing functions of the
DCP are still active, means that even when the voltage correction controller is activated, the
device can protect itself against overvoltages and overload conditions.
Note
As a result of the sampling and the dead times of the actual value channels, as we
ll as the
structure of the voltage corre
ction controller, this is not suitable for responding to dynamic
switching operations.
The following secondary conditions
must be satisfied in order that the voltage correction
controller functions correctly:
•
The voltage setpoint must be interconnected with p54150.
•
The external voltage actual values must be interconnected with p54151 (side 1) or
p54152 (side 2).
•
The corrected voltage setpoint (r54170) must be interconnected with the input of the
voltage controller p54100.
7.11.10 Current control
See function diagram 6820 in the SINAMICS DCP List Manual.
The current control comprises several components:
● Precontrol
to relieve the controller for setpoint changes.
The rate time (Tv) of the D component of the precontrol and the precontrol factor can be
parameterized.
● Current controller
Each power unit has its own current controller that is configured as adaptive PI controller.
The controller parameters proportional gain (Kp) and integral time (Tn) can be set
separately for the two current directions.
A delay of 2.1 ms is effective in the setpoint of the I component to reduce the settling
operations of the I component for setpoint changes.