Lenze i700 - Manual (Page 122)

5 Motor control & motor settings
5.12 Fine adjustment des motor model
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Lenze · i700 servo inverter · Reference manual · DMS 1.5 EN · 03/2014 · TD05
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5.12 Fine adjustment des motor model
The further commissioning steps are only required for servo controls if more stringent requirements
with regard to the torque linearity have to be met. During the commissioning process of Lenze
motors, typical values for the relevant parameters are provided. For motors of other manufacturers,
these values are to be requested from the motor manufacturer, or they have to be estimated.
5.12.1 Correction of the stator leakage inductance (Lss)...
...and the current controller parameters by means of the saturation characteristic
For the most part, the electrical characteristics of the motor are the relevant factors for an optimal
current controller setting (Vp, Ti), especially the stator resistance and the stator leakage inductance
(Lss). However, modern motors have their stator leakage inductance changed along with the
current level so that it is impossible to have an optimal current controller setting for all working
points at all times.
For applications with operating phases that involve very different current and torque requirements
and, at the same time, high requirements on dynamic drive behaviour, the i700 servo inverter
provides the possibility of the correction of the stator leakage inductance and the current controller
settings by means of the adjustable saturation characteristic.
The saturation characteristic is a typical characteristic of motors of one type/size. It does not depend
on the maximum process current of the motor in the prevailing application. Thus the defined values
should be based on the key data of the motors. These are rated motor current, peak motor current
for a limited time and the ultimate motor current.
The following picture shows a typical saturation characteristic of an MCS motor:
[5-1] Saturation characteristic: Inductance referring to the inductance for rated current
The saturation characteristic represents the change in inductance (L/Ln) as a function of the motor
current (I/Imax). The variables of both axes which were scaled to a reference value are represented
as percentages.
• When a Lenze motor is selected, the saturation characteristic is already filled with values typical
of the series.
0 % 10 % 20 % 30 % 40 % 50 % 60 % 70 % 80 % 90 % 100 %
0 %
20 %
40 %
60 %
80 %
100 %
120 %
I/I
max
L/L
n