Danfoss VLT HVAC Drive FC 102, Руководство по программированию, Страница: 123 / 250

3.14.4 14-3* Current Limit Control
The frequency converter features an integral current limit
controller which is activated when the motor current, and
thus the torque, is higher than the torque limits set in
parameter 4-16 Torque Limit Motor Mode and
parameter 4-17 Torque Limit Generator Mode .
When the current limit is reached during motor operation
or regenerative operation, the frequency converter tries to
reduce torque below the preset torque limits as quickly as
possible without losing control of the motor.
While the current control is active, the frequency converter
can only be stopped by setting a digital input to
[2] Coast
inverse or [3]Coast and reset inv. Any signal on terminals 18
to 33 are not active until the frequency converter is no
longer near the current limit.
By using a digital input set to
[2] Coast inverse
or
[3] Coast
and reset inv.
, the motor does not use the ramp down
time, since the frequency converter is coasted.
14-30 Current Lim Ctrl, Proportional Gain
Range: Function:
100 %
*
[0 - 500 %] Enter the proportional gain value for the
current limit controller. Selection of a high
value makes the controller react faster. Too
high a setting leads to controller
instability.
14-31 Current Lim Ctrl, Integration Time
Range: Function:
Size related
*
[0.002 - 2 s] Controls the current limit control
integration time. Setting it to a lower
value makes it react faster. A setting
too low leads to control instability.
14-32 Current Lim Ctrl, Filter Time
Range: Function:
Size related
*
[1 - 100 ms] Sets a time constant for the current
limit controller low-pass filter.
3.14.5 14-4* Energy Optimising
Parameters for adjusting the energy optimisation level in
both variable torque (VT) and automatic energy optimi-
sation (AEO) mode.
Automatic Energy Optimization is only active if
parameter 1-03 Torque Characteristics , is set for either [2]
Auto Energy Optim. Compressor or [3] Auto Energy Optim. VT .
14-40 VT Level
Range: Function:
66
%
*
[40 -
90 %]
NOTICE
This parameter cannot be adjusted while
the motor is running.
NOTICE
This parameter is not active when
parameter 1-10 Motor Construction is set to
[1] PM non-salient SPM .
Enter the level of motor magnetisation at low
speed. Selection of a low value reduces energy
loss in the motor, but also reduces load
capability.
14-41 AEO Minimum Magnetisation
Range: Function:
Size
related
*
[ 40 -
200 %]
NOTICE
This parameter is not active when
parameter 1-10 Motor Construction is
set to [1] PM non-salient SPM .
Enter the minimum allowable magnetisation
for AEO. Selection of a low value reduces
energy loss in the motor, but can also
reduce resistance to sudden load changes.
14-42 Minimum AEO Frequency
Range: Function:
Size
related
*
[5 - 40
Hz]
NOTICE
This parameter is not active when
parameter 1-10 Motor Construction is
set to [1] PM non-salient SPM .
Enter the minimum frequency at which
the automatic energy optimisation (AEO)
is to be active.
14-43 Motor Cosphi
Range: Function:
Size
related
*
[0.40 -
0.95 ] The Cos(phi) setpoint is automatically set
for optimum AEO performance during
AMA. This parameter should normally not
be altered. However, in some situations it
may be necessary to enter a new value to
fine-tune.
3.14.6 14-5* Environment
These parameters help the frequency converter to operate
under special environmental conditions.
Parameter Descriptions Programming Guide
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