15 dynamic servo control (dsc) – Efficient Networks Siemens Sinamics S120 User Manual
Page 106

Servo control
3.15 Dynamic Servo Control (DSC)
Drive Functions
106
Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4
3.15
Dynamic Servo Control (DSC)
Description
The function Dynamic Servo Control" (DSC) is a closed-loop control structure which is
computed in a fast speed controller clock cycle and is supplied with setpoints by the control
in the position controller clock cycle.
This allows higher position controller gain factors to be achieved.
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 system deviation (XERR) must be
included in the PROFIBUS-DP setpoint telegram or PROFINET IO with IRT (refer to
P0915).
● The position actual value must be transferred to the master in the actual value telegram
of PROFIBUS-DP or PROFINET IO via the encoder interface Gx_XIST1.
● When DSC is activated, the speed setpoint N_SOLL_B from the PROFIBUS DP or
PROFINET IO with IRT telegram is used as speed pre-control value.
● The internal quasi position controller uses the position actual value from the motor
measuring system (G1_XIST1) or the position actual value from the additional encoder
system (telegrams 06, 106, 116 or free telegrams).
The following PROFIdrive telegrams support DSC:
● Standard telegrams 5 and 6,
● SIEMENS telegrams 105, 106 ,116.
Further PZD data telegram types can be used with the telegram extension. It must then be
ensured that SERVO supports a maximum of 16 PZD setpoints and 19 PZD actual values.
Note
Synchronization is required on the control side and on the drive side for the operation of
DSC.