Description of the Software Modules and Parameters
Parameter manual
b maXX
BM5800
Document No.: 5.16029.03
487
3
3.7.5.1 Breakdown torque
The voltage is not only a limit for the q-component of the motor-voltage that is sustained
by the weakening of the magnetic flux (ASM) or the negative d-current injection, but also
for the d-component of the motor -voltage that can be kept by limiting a speed-dependent
torque current (breakdown torque limit).
Two limits of the breakdown torque are possible:
m
Breakdown torque limit: A feedforward controller limiting the maximum torque cur-
rent in dependence of the voltage and the speed.
m
Breakdown torque controller: A feedforward controller readjusting the maximum
torque current on the basic of the available voltage.
Figure 129:
ProDrive Breakdown torque
Breakdown torque limit (feedforward controller)
There is a speed-dependent torque current limit I
sq,K,limit
in the BM5800 so that the de-
manded Ud voltage can be limited to a defined limit U
d,Max
as follows:
I
sq,K,limit
U
d,Max
el
L
q
-----------------
=
