Siemens SINAMICS S120, Function Manual

Page: 169 / 1094

Servo control
4.16 Dynamic Servo Control (DSC)
Drive functions
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
169
4.16 Dynamic Servo Control (DSC)
The function Dynamic Servo Control" (DSC) is a closed-loop control structure which is
computed in a fast speed controller cycle and is supplied with setpoints by the controller in
the position controller cycle.
This allows higher position controller gain factors to be achieved.
Requirements
The following prerequisites are necessary to use the "Dynamic Servo Control" function:
● n-set mode
● Isochronous PROFIBUS DP or PROFINET IO with IRT
● The position controller gain factor (KPC) and the position deviation (XERR) must be
included in the setpoint telegram of PROFIBUS DP or PROFINET IO with IRT (refer to
p0922).
● The actual position value must be transferred to the master in the actual value telegram
of PROFIBUS DP or PROFINET IO with IRT via the encoder interface Gx_XIST1.
● When DSC is activated, the speed setpoint N_SOLL_B from the PROFIdrive telegram
from PROFIBUS DP or PROFINET IO with IRT is used as a speed precontrol value.
● The internal quasi position controller, DSC position controller (FP3090), uses the actual
position value G1_XIST1 from the motor measuring system or the actual position value
from an additional encoder system (telegrams 6, 106, 116, 118, 126, 136 and 138 or free
telegrams).
The following PROFIdrive telegrams support DSC:
● Standard telegrams 5 and 6
● SIEMENS telegrams 105, 106, 116, 118, 125, 126, 136, 138, 139
Further PZD data telegram types can be used with the telegram extension. It must then be
ensured that SERVO supports a maximum of 20 PZD setpoints and 28 PZD actual values.
Note
Synchronization is required on the control side and on the drive side for the operation of
DSC.
A detailed description of the DSC mode of operation is provided in function diagram 3090
(see SINAMICS S120/S150 List Manual).