3.15 Parameters: 14-** Special Functions
3.15.1 14-0* Inverter Switching
14-00 Switching Pattern
Option:
Function:
[0]
*
60 AVM Select the switching pattern: 60° AVM or SFAVM.
[1]
*
SFAVM
NOTE
The output frequency value of the frequency converter must
never exceed 1/10 of the switching frequency. When the
motor is running, adjust the switching frequency in
4-11 Motor Speed Low Limit [RPM]
until the motor is as
noiseless as possible. See also
and
the section
Special Conditions
in the VLT AutomationDrive
Design Guide.
14-01 Switching Frequency
Select the inverter switching frequency. Changing the switching
frequency can help to reduce acoustic noise from the motor.
Default depend on power size.
Option:
Function:
[0]
1.0 kHz
[1]
1.5 kHz
Default switching frequency for
355-1200 kW, 690V
[2]
2.0 kHz
Default switching frequency for
250-800 kW, 400V and 37-315
kW, 690V
[3]
2.5 kHz
[4]
3.0 kHz
Default switching frequency for
18.5-37 kW, 200V and 37-200
kW, 400V
[5]
3.5 kHz
[6]
4.0 kHz
Default switching frequency for
5.5 – 15kW, 200V and 11-30kW,
400V
[7]
*
5.0 kHz
Default switching frequency for
0.25 – 3,7kW, 200V and
0.37-7.5kW, 400V
[8]
6.0 kHz
[9]
7.0 kHz
[10]
8.0 kHz
[11]
10.0 kHz
[12]
12.0 kHz
[13]
14.0 kHz
[14]
16.0 kHz
NOTE
The output frequency value of the frequency converter must
never exceed 1/10 of the switching frequency. When the
motor is running, adjust the switching frequency in
4-11 Motor Speed Low Limit [RPM]
until the motor is as
noiseless as possible. See also
and
the section
Special conditions
in the VLT AutomationDrive
Design Guide.
NOTE
Switching frequencies higher than 5.0 kHz lead to automatic
derating of the maximum output of the frequency
converter.
14-03 Overmodulation
Option:
Function:
[0]
Off
Select
Off
[0] for no overmodulation of the output
voltage, in order to avoid torque ripple on the
motor shaft. This feature may be useful for
applications such as grinding machines.
[1]
*
On
Select On [1] to enable the overmodulation
function for the output voltage. This is the right
choice when it is required that the output voltage is
higher than 95% of the input voltage (typical when
running over-synchronously). The output voltage is
increased according to the degree of overmodu-
lation.
Overmodulation leads to increased torque ripple as
harmonics are increased.
Control in FLUX mode provides an output current of
up to 98% of the input current, regardless of
[2]
Optimal
14-04 PWM Random
Option: Function:
[0] Off No change of the acoustic motor switching noise.
[1] On Transforms the acoustic motor switching noise from a
clear ringing tone to a less noticeable ‘white’ noise. This is
achieved by slightly and randomly altering the
synchronism of the pulse width modulated output
phases.
14-06 Dead Time Compensation
Option:
Function:
[0]
Off
No compensation.
[1]
*
On
Activates dead time compensation.
Parameter Descriptions
FC 300 Programming Guide
138
MG.33.MB.02 - VLT
®
is a registered Danfoss trademark
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