Table of Contents
Advertisement
4.4
Configuration
The maximum cross current I
ue"
ue"
current and the actual maximum torque can be reduced by the power unit overload mon-
itoring (refer to "Bit mask of external drive current limit" Z138.6–).
Additionally, in the field weakening range the torque is limited by the maximum power.
Therefore, the maximum available torque
In the field weakening range it decreases inversely proportional to the speed (see
66–
Symmetric torque limit
The symmetric torque limit M
controller, which controls the torque-generating current. The correspondent limit for the
torque-generating current I
with
Flux
Kt
Kt
corr
Kt factor
Torque limits / torque current limits
M
(138.20)
max
| |
m
[Nm]
base speed
range
N
N
a)
107.7
Figure 66:
If there are several torque limits Z138.22–, that result from the torque current limits
Z138.2–, Z138.3–, Z138.14–,
erating simultaneously then the smallest limit is decisive (compare
112
Parameter manual b maXX BM3000
Document no.: 5.12001.07
of 820
Z19.5–
I
and by reduction the field current. The "Max. drive current actual val-
max act
Z19.5–
in general is the same as the maximum drive current Z19.6–. However, this
on page 112).
sq limit M
I
=
sq limit M
Magnetic flux set value in %
setl
Kt = Kt
· Kt factor, in Nm/A
corr
Kt correction factor,
Motor Kt in Nm/A
(138.22)
M
Lim
field weakening
N
-1
n [min ]
max mech
107.26
a) Asynchronous motor: Torque limit above
b) Asynchronous motor: Overlap of several limits
is calculated from the "Max. drive current actual val-
sq max
Z138.20–
is constant in the base speed range.
(Z138.22–) influences the set value of the cross current
limit
must be fit as follows.
M
limit
--------------------------- -
Flux
set
---------------- -
Kt
100
Z146.13–
Z138.23–
Z107.44–
M
(138.20) M
max
| |
m
[Nm]
base speed
range
N
b)
107.7
Z138.22–
Z138.15–
or from the breakdown torque-current limit op-
f
= (Iq
) =
Lim
Lim
min(138.2,138.3,138.14,138.15)
M
(138.22)
Lim
effective
limits
field weakening
N
-1
N
max mech
n [min ]
107.26
ZFig. 66–
Baumüller Nürnberg GmbH
ZFig.
M
=
Lim bd
f(138.18)
(b)). Note:
Hide quick links:
Advertisement
Chapters
Table of Contents
