Feedforward Control; Corresponding Data; Functional Description - Siemens SINUMERIK 840C Installation Instructions Manual

12 Functional Descriptions

12.14.1 Feedforward control

12.14.1
12.14.1.1
NC MD 312*
NC MD 465*
NC MD 1260* P-component feedforward control for rigid tapping
NC MD 1124* D-component feedforward control axes
NC MD 392*
NC MD 467*
NC MD 1324* Time constant (balancing filter) for feedforward control for rigid tapping
NC MD 1272* Setpoint smoothing filter for axes
NC MD 486*
NC MD
12.14.1.2
Static feedforward control
The feedforward control can be used to compensate position errors caused by a following
error within a range of 0 to 100 %. The following error is decreased according to the P-
component when feedforward control action is applied. A differential component of the control
can also be specified for axes, although this is generally not required. As a result of the static
feedforward control, the axis also travels "harder" into the specified position.
Recommended setting: Feedforward control P-component: 1000 ˆ = 100 %
Dynamic feedforward control
A very high static feedforward control setting may however cause severe overshoots on
acceleration. In this case, the partial setpoints can be passed to the position controller, delayed
by an additional time constant for feedforward control (balancing filter). This PT1 element
compensates the rise time of the speed control loop.
Recommended setting: Feedforward control time constant:
12–114
More user manuals on
Feedforward control
The FEEDFORWARD CONTROL function

Corresponding data

P-component feedforward control for axes
P-component feedforward control spindle
Time constant (balancing filter) for feedforward control for axes
Time constant (balancing filter) for feedforward control for spindles
Setpoint smoothing filter for spindles
For parameter set switchover (see functional description)

Functional description

Setpoint
ManualsBase.com
is an option.
T
feedf
T = Rise time of the speed
n
Actual value
Speed
n
© Siemens AG 1992 All Rights Reserved
10.94
.
=0.5 T
n
control loop
6FC5197- AA50
SINUMERIK 840C (IA)