Lenze i950 Series, Manual, Page: 305 / 500

13.11.4 Manual "current pulse" test mode
The stator resistance and the stator inductance of the inverter must be adapted to the electri-
cal characteristics of the motor. For an experimental adjustment, the manual "Current pulse"
test mode can be used.
This test mode is provided for adjusting the current controller in the "Servo con-
trol for synchronous motor/asynchronous motor" operating mode and is not
suitable for adjusting the Imax controller in the "V/f characteristic control (VFC)"
operating mode!
In the manual "Current pulse" test mode, setpoint step-changes are applied to the current
controller input subsequent to controller enable. The step responses must then either be
recorded using an oscilloscope and a clamp-on ammeter, or using the oscilloscope function of
the inverter. It is the objective to optimise the two "Gain" and "Reset time" current controller
parameters by evaluating the step responses so that a speedy current characteristic is ach-
ieved, which, if possible, is free of harmonics.
In the case of motors with single pole windings, satisfactory results are possibly only achieved
with a current-dependent correction of the current controller parameters. For this purpose, a
characteristic is stored in the inverter, which describes the current dependance of the stator
leakage inductance and which tracks the current controller gain.
After the inverter has been enabled, the synchronous motor makes a jerky com-
pensating movement if its pole position does not correspond to the starting
angle.
The motor phase U is energized with a DC current the level of which is determined via the
following equation.
_ test
2 *I [%]*
100%
rated
phase U
I
I
=
In motor phases V and W, half of this DC current flows (negative; from the motor).
_ , _
0.5* 2 * [%]*
100%
rated
phase V W test
I
I I
= -
The following parameters are relevant to the calculation:
• Manual test mode: setpoint current
4
0x2835:001
• Motor rated current
4
0x6075
•
Read only: current phase U 0x2D83:002
•
Read only: current phase V 0x2D83:003
•
Read only: current phase W 0x2D83:004
Conditions for the execution
•
The motor must be parameterised completely.
•
The motor utilisation (I²xt) monitoring must be parameterised and switched to active.
4
Motor overload monitoring (i²*t)
^
288
•
The motor must rotate freely.
•
The inverter is error-free and switched on.
•
The rotor of synchronous motors must be in the pole centre during the test. For some syn-
chronous motors, it might be required to align and lock the rotor in the pole centre.
•
Using the manual test mode "current/frequency" is useful for a one-time alignment of
the rotor with the following settings:
R.m.s. value = 70 ... 100 %; frequency = 0 Hz; starting angle = 0°
4
Manual "current/frequency" test mode
^
304
•
Fixation by means of the holding brake or the use of external fixation aids
Configuring the motor control
Testing the motor control
Manual "current pulse" test mode
305