Ramp-Function Generator - Siemens SINAMICS G120 Operating Instructions Manual

8.13.2

Ramp-function generator

Data
Parameter range:
Warnings:
Faults:
Function chart number:
Description
The ramp-function generator (RFG) is used to limit the acceleration when the setpoint
changes according to a step function. This therefore helps to reduce the stressing on the
mechanical system of the machine. An acceleration ramp and a braking ramp can be set
independently of one another using the ramp-up time P1120 and the ramp-down time
P1121. This allows a controlled transition when the setpoint is changed (see figure below).
Figure 8-43
In order to avoid torque surges at the transitions (constant velocity phase ←→
accelerating/braking phase), additional rounding-off times P1130 ... P1133 can be
Control Units CU240S
Operating Instructions, 11/2006, A5E00766042B AA
=
= t
f - P 1082 up
f
2 1
+
P1130 P1131
>
P1120
2
=
t
up
+
p1132 P1133
>
P1121
2
+
P1130 P1131
≤
P1120
2
=
t
up
+
P1132 P1133
≤
P1121
2
Ramp-function generator
P1120, P1121
r1119, r1170
P1130 ... P1142
-
-
FP5000, FP5300
+
P1130 P1131
+
P1120
2
+
f -
P 1130 P 1131 f
2 1
+ ⋅
( P1120)
2 P1082
+
f -
P1130 P1131 f
2 1
+ ⋅
P1120
2 P1082
8.13 Setpoint channel
+
P1132 P1133
= +
P1121
t
down
2
+
P 1132 P 1133
= + ⋅
( P1121)
t
down
2
+
P1132 P1133 f
2
= + ⋅
P1121
t
down
2 P1082
Functions
f -
f
2 1
P1082
f -
1
8-61