YASKAWA AC Drive-A1000 Technical Manual page 167

n C6-02: Carrier Frequency Selection
Sets the switching frequency of the drive output transistors. Changes to the switching frequency lower audible noise and reduce
leakage current.
Note: Increasing the carrier frequency above the default value automatically lowers the drive current rating.
Carrier Frequency on page
No. Parameter Name
C6-02 Carrier Frequency Selection
Note: The default setting for the carrier frequency differs based on the type of motor and the Duty Mode selection. The default is 2 kHz in HD, and
"Swing PWM1" in ND. When using a PM motor, the default carrier frequency is 5.0 Hz.
Settings:
C6-02 Carrier Frequency
1 2.0 kHz
2 5.0 kHz (4.0 kHz)
3 8.0 kHz (6.0 kHz)
4 10.0 kHz (8.0 kHz)
Note: 1. Swing PWM uses a carrier frequency of 2.0 kHz as a base, then applies a special PWM pattern to reduce the audible noise.
2. The value in parenthesis indicates the carrier frequency for AOLV/PM.
Guidelines for Carrier Frequency Parameter Setup
Speed and torque are unstable at low speeds
Noise from the drive affects peripheral devices
Excessive leakage current from the drive
Wiring between the drive and motor is too long
Audible motor noise is too loud
<1> The carrier frequency may need to be lowered if the motor cable is too long. Refer to the following table.
<2> The default carrier frequency in ND is Swing PWM (C6-02 = 7), using a 2 kHz base. Increasing the carrier frequency is permissible when the drive
is set for Normal Duty, however the drive rated current reduced when the carrier frequency is increased.
Wiring Distance
Recommended setting value for C6-02
n C6-03, C6-04, C6-05: Carrier Frequency Upper Limit, Lower Limit, Proportional Gain
These parameters set a user-defined or a variable carrier frequency. Set C6-02 to F to set the upper and lower limits and the
carrier frequency proportional gain.
No.
C6-03
C6-04 Carrier Frequency Lower Limit (V/f Control only)
C6-05 Carrier Frequency Proportional Gain (V/f Control only)
Setting a Fixed User Defined Carrier Frequency
A carrier frequency between the fixed selectable values can be entered in parameter C6-03 when C6-02 is set to F.
In V/f Control, adjust parameter C6-04 to the same value as C6-03.
Setting a Variable Carrier Frequency (V/f Control)
In V/f Control, the carrier frequency can be set up to change linearly with the output frequency by setting the upper and lower
limits for the carrier frequency and the carrier frequency proportional gain (C6-03, C6-04, C6-05) as shown in
YASKAWA ELECTRIC SIEP C710616 31B YASKAWA AC Drive – A1000 Technical Manual
168.
C6-02
5
6
7
8
Symptom
<1>
Up to 50 m
1 to F (up to 15 kHz)
Parameter Name
Carrier Frequency Upper Limit
Setting Range
1 to F
Carrier Frequency
12.5 kHz (10.0 kHz)
15.0 kHz (12.0 kHz)
Swing PWM 1
Swing PWM 2
Lower the carrier frequency.
Increase the carrier frequency or use Swing PWM.
Up to 100 m
1 to 2 (up to 5 kHz), 7 (Swing
PWM)
Setting Range
5.3 C: Tuning
Refer to Rated Current Depending on
Default
Determined by A1-02, o2-04.
Reset when C6-01 is changed.
C6-02 Carrier Frequency
9 Swing PWM 3
A Swing PWM 4
F User defined (C6-03 to C6-05)
Remedy
<2>
Greater than 100 m
1 (up to 2 kHz), 7 (Swing PWM)
1.0 to 15.0 kHz
Determined by
1.0 to 15.0 kHz
0 to 99
5
Default
C6-02
Figure 5.39.
167