Closed-Loop Position Control - Siemens Sinamics S120 Function Manual

7.7

Closed-loop position control

7.7.1 General features
The position controller essentially comprises the following parts:
● Position actual value conditioning (including the lower-level measuring probe evaluation
● Position controller (including limits, adaptation and the pre-control calculation)
● Monitoring functions (including standstill, positioning, dynamic following error monitoring
● Position tracking of the load gear (motor encoder), using absolute encoders for rotary
7.7.2 Position actual value conditioning
7.7.2.1 Features
● Correction value (p2512, p2513)
● Setting value (p2514, p2515)
● Position offset (p2516)
● Position actual value (r2521)
● Velocity actual value (r2522)
● Motor revolutions (p2504)
● Load revolutions (p2505)
● Spindle pitch (p2506)
● Position tracking (p2720ff)
7.7.2.2 Description
The position actual value conditioning converts the actual position value into a neutral
distance unit LU (Length Unit). To do this, the function block uses the encoder
evaluation/motor control with the available encoder interfaces Gn_XIST1, Gn_XIST2,
Gn_STW and Gn_ZSW. These just provide position information in encoder pulses and fine
resolution (increments).
The position actual value is conditioned, regardless of whether the position controller is
enabled immediately after the system has booted, as soon as valid values are received via
the encoder interface.
Parameter p2502 (encoder assignment) is used to define from which encoder (1, 2 or 3), the
position actual value is sensed.
Drive functions
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
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and cam signals)
axes (modulo) as for linear axes.
Function modules
7.7 Closed-loop position control
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