NORD Drivesystems BU0700 - Manual (Page 74)

NORDAC SK 700E Operating Manual
74 Subject to technical alterations BU 0700 GB-1411
Parameter Setting value / Description / Note Available with option
P315 (P) Field current controller P ENC POS
0...800 %
[ 200 ]
Current controller for the field current. The higher the current controller parameters are set, the more
precisely the current setpoint is maintained. Excessively high values for P315 generally lead to high
frequency vibrations at low speeds. On the other hand, excessively high values in P316 generally
produce low frequency vibrations across the whole speed range If the value "Zero" is entered in P315
and P316, then the field current controller is switched off. In this case, only the motor model precontrol
is used.
P316 (P) Field current controller I ENC POS
0...800 % / ms
[ 125 ]
I-component of the field current controller. See also P315 >Field current controller P<
P317 (P) Field current controller limit ENC POS
0...400 V
[ 400 ]
Determines the maximum voltage increase of the torque current controller. The higher the value, the
greater is the maximum effect that can be exercised by the field current controller. Excessive values in
P317 can specifically lead to instability during transition to the field reduction range (see P320). The
values for P314 and P317 should always be set roughly the same, so that the field and torque current
controllers are balanced.
P318 (P) P-Weak ENC POS
0...800 %
[ 150 ]
The field weakening controller reduces the field setpoint when the synchronous speed is exceeded.
Generally, the field weakening controller has no function; for this reason, the field weakening controller
only needs to be set if speeds are set above the nominal motor speed. Excessive values for P318 /
P319 will lead to controller oscillations. The field is not weakened sufficiently if the values are too small
or during dynamic acceleration and/or delay times. The downstream current controller can no longer
read the current setpoint.
P319 (P) I-Weak ENC POS
0...800 % / ms
[ 20 ]
Affects only the field weakening range, see P318 >Field weakening controller P<
P320 (P) Weak Border ENC POS
0...110 %
[ 100 ]
The field weakening limit determines at which speed / current the controller will begin to weaken the
field. At a set value of 100% the controller will begin to weaken the field at approximately the
synchronous speed.
If values much larger than the standard values have been set in P314 and/or P317, then the field
weakening limit should be correspondingly reduced, so that the control range is actually available to
the current controller.
P321 (P) Speed control I brake off ENC POS
0... 4
[ 0 ]
During brake ventilation time (P107/P114), the I-component of the speed controller is increased. This
leads to better load take-up, especially with vertical movements.
0 = Speedctrl I*1
1 = Speedctrl I*2
2 = Speedctrl I*4
3 = Speedctrl I*8
4 = Speedctrl I*16
P325 Function encoder ENC POS
0...4
[ 0 ]
The actual speed value supplied by an incremental encoder to the FI can be used for various functions
in the FI.
0 = Speed measurement Servo mode: The actual motor speed value is used for the FI servo mode.
The ISD control cannot be switched off in this function.
1 = PID actual frequency value: The actual speed of a system is used for speed control. This
function can also be used for controlling a motor with a linear characteristic curve. It is also
possible to use an incremental encoder for speed control that is not mounted directly onto the
motor. P413
– P416 determine the control.
2 = Frequency addition: The speed determined is added to the current setpoint value.
3 = Frequency subtraction: The speed determined is subtracted from the actual setpoint.
4 = Maximum frequency: The maximum possible output frequency / speed is limited by the speed of
the encoder.