Description of the Software Modules and Parameters
Parameter manual
b maXX
BM5800
Document No.: 5.16029.03
131
3
Figure 45:
Characteristic curve of the IPMSM
The field weakening in the BM5800 operates via the standard field weakening controller
and the breakdown torque controller. As field weakening is impressed always at the
IPMSM the field current controller calculates a minimum ld current (
must be impressed in the motor at the least. The output of the field weakening controller
is multiplied by the maximum current from the MTPF characteristic. The field weakening
controller should provide a lover threshold than the breakdown torque controller. If the re-
quired voltage rises over the starting threshold of the breakdown controller the lq current
is limited. From this maximum total current during a present flux (
) and the min-
) the maximum total current of the IPMSM (
) is cal-
culated. This ensures that no more current impressed and the maximum torque is
reached.
