Field weakening, reduction of the maximum torque

Question:

What can be the reason that in case of vector control the drive does not reach the demanded torque / speed above the rated speed?

Answer:

To be able to operate the motor with stall protection, the controller reduces the torque or current limits in the field setting range (above the rated speed).
Effect: the maximum current set is not achieved. The maximum torque available in the field setting range reduces.

Remedy:

Increase MCTRL-HI/LO-M-LIM to 200 %.

Sequence of the torque limit in case of vector control:

1. MCTRL-HI/LO-M-LIM = 100 %; reduction with 1/n from nN
2. MCTRL-HI/LO-M-LIM = 200 %; reduction with 1/n from 2 nN