Servo Control - Siemens SINAMICS S120 Function Manual

Servo control

This type of closed-loop control enables operation with a high dynamic response and
precision for a motor with a motor encoder.
Comparison of servo control and vector control
The table below shows a comparison between the characteristic features of the servo and
vector controls.
Table 3- 1
Subject
Typical applications
Maximum number of drives that
can be controlled by one Control
Unit.
Dynamic response
Drive functions
Function Manual, (FH1), 10/2008, 6SL3097-2AB00-0BP5
Comparison of servo control and vector control
Servo
Drives with highly dynamic
motion control.
Drives with high speed and
torque accuracy
(servo synchronous motors).
Angular-locked synchronism
with isochronous PROFIdrive.
For use in machine tools and
clocked production machines
1 infeed + 6 drives
(with sampling rate of current
controller 125 μs / speed
controller
125 μs)
1 infeed + 2 drives
(with sampling rate of current
controller 62.5 μs / speed
controller
62.5 μs)
High
Vector
Speed and torque-controlled
drives with high speed and
torque accuracy, particularly in
operation without an encoder
(sensorless operation).
1 Active Line Module +
2 Motor Modules
(with sampling time of current
controller 250 µs / speed
controller 1 ms)
1 Active Line Module +
4 Motor Modules
(with sampling time of current
controller 400 μs/500 μs / speed
controller 1.6 ms/2ms)
V/f control:
1 Active Line Module +
8 Motor Modules
(with sampling time of current
controller 500 µs / speed
controller 4 ms)
Average
3
65