Optimising Dynamic Performance And Field Weakening Behaviour - Lenze 8400 StateLine C Reference Manual

8400 StateLine C | Reference manual
Motor control (MCTRL)
Sensorless vector control (SLVC)
5.7.4.3

Optimising dynamic performance and field weakening behaviour

In the Lenze setting, the torque controller has been preset in such a way that robust and
stable operation with a moderate dynamic response is enabled over the entire speed
range. Retrospective optimisation of the controller parameters is not necessary.
Parameter
C00073/2
C00074/2
A greater dynamic performance of the sensorless vector control can be achieved by
reducing time constant Ti of the speed controller (C00074/2).
A greater dynamic performance of the field weakening function can be achieved by setting
a time constant ≤ 15 ms. This means for actual speeds above rated speed a better torque-
speed-characteristic in the field weakening range:
 Torque controller time constant Ti > 15 ms
 Torque controller time constant Ti ≤ 15 ms
[5-11] Speed / torque characteristic diagram in the field weakening range
 For Ti > 15 ms (see ), the actual speed value slightly drops in the field weakening
range if the load torque increases in the motor mode.
 For Ti ≤ 15 ms (see ), the speed remains stable in the field weakening range if the
torque is within the M/n characteristic field highlighted in grey.

Tip!
For applications with high dynamic performance and speed/torque accuracy
requirements in the field weakening range, we recommend a time constant
Ti ≤ 15 ms.
In this case, the maximum torque should be limited via the nTorqueMotLimit_a
and nTorqueGenLimit_a process input signals to 1.5 x M
operation in the field weakening range.
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Info
SLVC: Vp torque controller
SLVC: Ti torque controller
M
0
M
N
n n
N
L
Lenze setting
M
1
M
N
n n
N
N
Firmware ≤ 11.00 - DMS 8.0 EN - 10/2011
Value Unit
1.25
30 ms
to ensure stable