Lenze 8400 - Manual (Page 196)

5 Motor control (MCTRL)
5.7 Sensorless vector control (SLVC)
196
Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
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5.7.4.7 Optimising field feedforward control and torque feedforward control
At the start of an acceleration process and at the end of a deceleration process, the field current
(nReaktCurrentId_a) may oscillate.
• Especially when accelerating via small acceleration ramps, these oscillations become obvious by
the speed being unable to follow the setpoint or speed drops during acceleration.
• Oscillating can be reduced by increasing the gain of the field current controller in C00985 . A
small increase of the cross current controller gain in C00986 can further improve the starting
performance for small acceleration ramps.
In the field weakening range, the cross current (nEffCurrentIq_a) may oscillate when an acceleration
process starts or a deceleration process ends.
• These oscillations can be reduced by again increasing the cross current controller gain slightly
in C00986 .

Note!
The setting of C00985 and C00986 reduces the torque setting range.