Dynamic Servo Control (Dsc) - Siemens SINAMICS S120 Function Manual

5.18

Dynamic Servo Control (DSC)

Overview
Function "Dynamic Servo Control" (DSC) is a closed-loop control structure that computes the
position controller in a fast speed controller clock cycle and is supplied with setpoints by the
control system 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).
Function description
A detailed description of the mode of operation is provided in function diagram 3090 (see
SINAMICS S120/S150 List Manual).
Note
Synchronization is required on the control side and on the drive side for the operation of DSC.
PROFIdrive telegrams
The following PROFIdrive telegrams support DSC:
● Standard telegrams 5 and 6
● SIEMENS telegrams: 5, 6, 105, 106, 116, 118, 125, 126, 136, 138, 139, 146, 148, 149 and
166
Further PZD data telegram types can be used with the telegram extension. It must be observed
that SERVO control mode supports a maximum of 20 PZD setpoints and 28 PZD actual values.
Drive functions
Function Manual, 06/2019, 6SL3097-5AB00-0BP2
Servo control
5.18 Dynamic Servo Control (DSC)
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