Yaskawa 1000 Hz High Frequency - Manual (Page 16)

6 Application Notes
16 YASKAWA ELECTRIC EZZ020793 1000 Hz High Frequency Custom Software Supplement
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Fine Tuning the Carrier Frequency
It is important to optimize the carrier frequency to improve the motor current waveform.
This will improve motor speed stability and torque performance and also limit hunting and
oscillation at higher speeds.
Use one of the following setting recommendations to fine tune the carrier frequency for
optimum motor performance:
1. For a flat 7.0 kHz across the speed range: Set C6-02 = “F” with C6-03 = “7.0”, C6-04 =
“7.0”, and C6-05 = “0”. The 7.0 kHz across the output frequency range keeps the carrier
frequency as high as possible.
2. To create a ramped carrier frequency pattern to keep the output frequency and
carrier frequency at a constant ratio:
• Set C6-02 = “F” to build a custom pattern.
• Set C6-03 = “7.0 kHz” so the motor will run at 7.0 kHz at top speed.
• Set C6-04 = “1.0 kHz” so the carrier frequency will be ramped for the greatest output
frequency range.
• Solve the following formula for C6-05:
C6-05 = [7000 Hz / (2 x E1-04)]
The C6-05 setting range is 7 ~ 99, however a setting lower than 7 disables the ramp
function and C6-03 is used across the output frequency range. For motors with output
frequencies greater than 500 Hz, use C6-05 = 7.
• Solve for corner output frequencies A and B
A Hz = [1000 Hz / (2 x C6-05)]
B Hz = [7000 Hz / (2 x C6-05)]
Figure 5
Figure 5 Carrier Frequency
C6-03 =
7.0 kHz
A Hz
Carrier
Frequency
(Fc)
Output
Frequency
(Fout) B Hz
Parameter C6-02 = F
C6-04 =
1.0 kHz
E1-04
Fc = 2 x C6-05 x Fout