Yaskawa Matrix Converter - Manual (Page 203)

6
-38
Machine Protection
This section explains functions for protecting the machine.
‹ Reducing Noise and Leakage Current
The switching frequency of the output transistors in the MxC can be changed to reduce carrier noise and leak-
age current from the motor.
„ Related Parameters
* 1. Fixed to 2:4 kHz for V/f.
For Open Loop Vector Control, can select from 2:4 kHz or 4:8 kHz (Fixed to 2: 4 kHz for a 200 V class MxC for 45 kW and a 400 V class MxCs for 22
kW and 45 kW).
* 2. Fixed to 2: 4 kHz for 400 V class MxCs for 110 kW and 160 kW.
„ Control Method and Carrier Frequency Settings
Carrier frequency settings are restricted as listed in the following table according to the control method selec-
tion.
* Fixed to 2: 4 kHz for 200 V class MxC for 45 kW and 400 V class MxCs for 22 kW and 45 kW
Note: 1. Fixed to 2: 4 kHz for 400 V class MxCs for 110 kW and 160 kW.
2. The upper limit of the carrier frequency depends on the MxC capacity.
„ Carrier Frequency Setting Precautions
When selecting the carrier frequency, observe the following precautions.
• Adjust the carrier frequency according to the cases shown below.
If the wiring distance between MxC and motor is long: Set the carrier frequency low. (Use the following
values as guidelines.)
If speed and torque are inconsistent at low speeds: Lower the carrier frequency.
If there is too much leakage current from the MxC: Lower the carrier frequency.
If the metallic noise from the motor is too loud: Raise the carrier frequency.
Parameter
Number
Name
Description
Setting
Range
Default
Change
during
Run
Control Methods
Display V/f
Open
Loop
Vector
Flux
Vector
C6-02
Carrier Frequency
Selection Select carrier frequency pattern.
2: 4 kHz
4: 8 kHz
6: 12 kHz
2, 4, or
6
*1 *2
2 No Q Q Q
CarrierFreq Sel
Control Method Carrier Frequency
V/f Control 2: 4.0 kHz
Open Loop Vector Control
2: 4.0 kHz
4: 8.0 kHz
*
Flux Vector Control
2: 4.0 kHz
4: 8.0 kHz
6: 12.0 kHz
Wiring Length 50 m or less 100 m or less Over 100 m
C6-02 (Carrier Frequency
Selection) setting 2, 4, or 6
(4, 8, or 12 kHz)
2 or 4
(4 or 8 kHz)
2 (4 kHz)