Siemens SINAMICS S120 Function Manual page 429

Description of the k
T
The adaptation of the torque constants for synchronous motors is used to improve the
absolute torque accuracy for the control (closed-loop) of synchronous motors. The
magnetization of the permanent magnets varies as a result of production tolerances and
temperature fluctuations and saturation effects. The function "k
constant k
the k
inner motor torque. The frictional losses must be compensated from the friction characteristic
using a supplementary torque.
The k
order to achieve a high torque accuracy. Before using the k
(p1909, p1910) must be performed with activated k
for stator resistance (p0350), leakage inductance (p0356) and voltage emulation errors
(p1952, p1953) are determined. The cable resistance must be entered in p0352 before
motor identification.
The motor should be at room temperature when the identification routine is carried out.
Compensation of the voltage emulation error must be activated (p1780.8 = 1). The motor
temperature (p0600) should be recorded via a KTY sensor (p0601 = 2 or 3).
The k
dependent quantities. The estimate is less accurate if a motor temperature sensor is not
connected.
The k
the converter always has small inaccuracies. The lower the output voltage and speed, the
more inaccurate the estimate. This is the reason why the estimation is deactivated below a
specific speed. The estimated value is smoothed using time constant p1795. The correction
value for the torque constant is displayed in r1797.
By identifying the torque constant k
accuracy can be improved also below the speed threshold (p1752).
The k
Drive functions
Function Manual, (FH1), 01/2013, 6SL3097-4AB00-0BP3
estimator
[Nm/A] in the control to the prevailing magnetization. It only makes sense to use
T
estimator in conjunction with the friction characteristic as the k
T
estimator requires the most accurate values for the motor parameters as possible in
T
estimator requires the motor temperature in order to track/correct the temperature-
T
estimator is only activated above a specific speed (p1752). The terminal voltage of
T
estimator is activated using p1780.3 and the voltage compensation using p1780.8.
T
7.6 Extended torque control (kT estimator, servo)
estimator. In this procedure, the values
T
using the rotating motor identification routine, the torque
T
Function modules
estimator" adapts the torque
T
estimator corrects the
T
estimator, a motor identification
T
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