Siemens SINAMICS DCM Operating Instructions Manual page 408

Descriptions of functions
10.9 Setpoint channel
Ramp-function-generator tracking
The ramp-function generator output (r52190) is limited to the following values when ramp-
function generator tracking is active:
When p50170 = 1 (closed-loop torque control), the following applies:
When p50170 = 0 (closed-loop current control), the following applies:
Φmotor
nact
+Mlimit
-Mlimit
+IA.limit
-IA.limit
Kp
If, however, the value added to nact would be less than 1%, then +1% or is –1% is added.
The "Ramp-function generator tracking" function prevents the ramp-function generator value
from straying too far from the actual speed value if the torque or current limit has been
reached.
Note:
When ramp-function generator tracking is active, the filtering time of the speed setpoint
p50228 should be low (ideally = 0).
Limiting after ramp-function generator
This limiting stage can be used by freely selecting the input signal, completely independently
from the ramp-function generator.
A distinguishing feature of this type of limiting is that lower limiting can also be set to positive
values and upper limiting to negative values (see p50300 and p50301). In this case, a limit
set using this method acts as a lower limit (lower limiting value) for the output signal of the
ramp-function generator, with the sign inverted.
Example:
p50632.01-04 = 1 (= 100.00%)
p50300 = 100.00 (%)
p50301 = 10.00 (%)
p50633.01-04 = 9 (= -100.00%)
results in the value range of r52170 being limited to between +10.00% and +100.00%.
Velocity signal dv/dt (r52191)
This signal specifies the change in ramp-function generator output r52190 during the time
set in p50542.
406
Scaled motor flux (1 at rated excitation current)
Actual speed value (r52167)
Smallest positive torque limit (r52143)
Smallest negative torque limit (r52144)
Smallest positive current limit (r52131)
Smallest negative current limit (r52132)
Active speed controller gain
Operating Instructions, 1.2012, C98130-A7066-A1-05-7619
SINAMICS DCM DC Converter