Hitachi SJ700-2 Marine Battery User Manual


 
Chapter 4 Explanation of Functions
4 - 43
4.2.35 Carrier frequency setting
The carrier frequency setting function (b083) allows you to change the
carrier frequency of the PWM waveform output from the inverter.
Increasing the carrier frequency can lower the metallic noise from the motor, but may increase the inverter
noise and current leakage.
You can use this function effectively to avoid resonance of the mechanical system and motor.
Item Function code Range of data Description
Carrier frequency
setting
b083 0.5 to 15.0 (kHz) (*1)
*1 The maximum carrier frequency varies depending on the inverter capacity.
When increasing the carrier frequency (fc), derate the output current as shown in the following table:
Derated output current is to be set as electronic thermal protection level (4.2.29).
Derating is not needed when electronic thermal level is already set to lower then derating level.
Voltage
class
200 V class 400 V class
Inverter
capacity
Maximum
fc (kHz)
Derating at fc=15 kHz
Maximum
fc (kHz)
Derating at fc=15 kHz
15kW 12 95% (60.8 A or less) 14 95% (30.4A or less)
18.5kW 10 90% (68.4A or less) 10 90% (34.2A or less)
22kW 7 70% (66.5A or less) 6 75% (36.0A or less)
30kW 5 80% (96.8A or less) 10 75% (43.5A or less)
37kW 10 75% (108.7A or less) 8 80% (60.0A or less)
200 V class
400 V class
If you use the inverter with settings that exceed the rated maximum carrier frequency or derated output
current (with a maximum carrier frequency of 15 kHz), the inverter may be damaged or its life may be
shortened.
60
55
100
95
90
85
80
75
70
65
15kW
18.5kW
37kW
30kW
0.5 2 4 6 8 10 12 15 14
22kW
37kW
60
55
100
95
90
85
80
75
70
65
15kW
22kW
0.5 2 4 6 8 10 12 15 14
18.5kW
30kW
Carrier frequency (kHz) Carrier frequency (kHz)
Derating of output current
Derating of output current