Kemppi Minarc 120AU Service Manual

Operation principle
VDC
t
105
13µs
M
a
x
.
0
,
5
~ + 320 V
1/3
V1
V2
When IGBTs V1 and V2 are non-conductive no power is transferred. Power is altered by
changing the transistor´s timing (PWM).
Main circuit
Minarc power sources are”dual-Forward” inverters, controlled by PWM technology.
Switching components are IGBT transistors. The operation frequency is ~ 80 kHz.
Below is a picture of the ”dual-forward” inverter operation principle.
+
t
+
t
X5
X1
X3
R
3
1
R
3
2
L2
C
9
C
5
C
1
0
L1
R
3
0
R
2
3
C
1
5
V
2
1
V
2
0
V11
C
2
,
C
3
,
C
4
V
7
,
V
3
V
1
,
V
2
V
4
,
V
5
,
V
6
V
8
,
V
9
,
V
1
0
T
0
0
1
T
2
K1
X11/12
V
1
6
C
1
3
R9
X13
X12
Primary circuit connection, Minarc 150/150 VRD.
4

Kemppi Minarc 120AU Specifications

General

Brand	Kemppi
Model	Minarc 120AU
Category	Welding System
Language	English