Description of the Software Modules and Parameters
Parameter manual
b maXX
BM5800
Document No.: 5.16029.03
93
3
Figure 37:
"Max. torque current" modes 19.8 at the asynchronous motor
a) Field current dependence (no external total current limit is assumed).
b) External total current limit dependence (field weakening is not assumed).
19.9
Field current preset value
At an
asynchronous
machine and if the "Permanent field current" field weakening type
is set (
bit 0 = 1) then any field current is permanently preset (lsd set value
= Field current preset value
>
19.9
<
). This way the field weakening controllers
and flux controllers are deactivated. For example here the magnetizing current of the
ASM at the nominal point can be entered.
However, the required field current can differ or be lower at field weakening as well as
greater when magnetizing. If the field weakening type was set "at the voltage limit"
(
bit 0 = 0) the parameter
>
19.9
<
has no meaning for the ASM.
If a
synchronous
machine is operated in field weakening here a negative current value
must be entered. At a synchronous machine and if the field weakening type "permanent
field current " is set ((
bit 0 = 1) here any negative field current can permanently
be preset (Isd-set value
= Field current preset value
>
19.9
<
). This way the field
weakening controller is deactivated. For example here the required field current at maxi-
mum speed and torque can be entered. The required field current amplitude however can
differ from that value if the speed and torques are lower than the maximum values. If the
field weakening type "at the voltage limit" is set (
bit 0 = 0) then the parameter
>
19.9
<
imposes a field current limit to the field weakening controller and the controlled
field weakening characteristic.
5000_0350_rev01_int
n [min ]
N
107.7
N
-1
n [min ]
N
N
-1
t
Isd-Lim 146.12
t
LT-Imax 19.6
= LT-Imax
= LT-Imax
0
0
0
0
0
0
0
0
a)
b)
loading mode standard
loading mode ASM-isdMax
current mode
LT-Imax-act
2
isd-set
2
=
isqMax
19.8
isqMax
19.8
isd-act
47.2
Isd-nom
LT-Imax-act
19.5
LT-Imax-act
2
isd-set
2
=
LT-Imax-act
2
2
Isd-Lim
=
external
drive current limit