Chapter 4 Parameters
VFD-EL-W
4-39
Example uses are blowers, punching machines, centrifuges and pumps.
RUN
STOP
Frequency
Time
Time
output
frequency
output
frequency
motor
speed
motor
speed
operation
command
operation
command
stops according to
decel eration time
free run to stop
ramp to stop and free run to stop
EF
frequency output
motor
speed
EF
operation
command
stops according to
decel eration time
When Pr.02.02 is set to 2 or 3
frequency
output
free run to stop
operation
command
When Pr.02.02 is set to 0 or 1
motor
speed
02.03
PWM Carrier Frequency Selection Unit: 1
Default: 8
Settings 2–12 kHz
Determines the PWM carrier frequency of the AC motor drive.
2kHz
8kHz
12kHz
Carrier
Noise
Noise or leakage
current
Heat
Dissipation
Current
Wave
Significant
Minimal
Significant
Minimal
Minimal
Significant
Minimal
Significant
From the table, you can see that the PWM carrier frequency has a significant influence on the electromagnetic
noise, AC motor drive heat dissipation, and motor acoustic noise. The PWM carrier frequency is decreased
automatically according to the ambient temperature and output current of the AC motor drives. It is used to
prevent the AC motor drive from overheating and thus extend the IGBT’s life. Increasing the PWM carrier
frequency may reduce the noise of motor operation, but interference measures have to be taken for the
consideration of overall wiring.