Functional Principle Of Medium-Frequency Welding; Fig. 3:Block Diagram Overview: Psi 6000 With Transformer; Fig. 4:Detailed Block Diagram Of A Medium-Frequency Inverter System - REXROTH PSG series Operating Instructions Manual

1070087062 / 04 | PSG xxxx
5.2

Functional principle of medium-frequency welding

Mains
50/60 Hz
L1
L2
L3

Fig. 4:Detailed block diagram of a medium-frequency inverter system

PSI 6xxx
Control unit

Fig. 3:Block diagram overview: PSI 6000 with transformer

The MF inverter integrated in the PSI controls the welding transformer
by a bipolar, rectangular voltage with a frequency of 1000 Hz. In order to
influence the resulting heat (%I) in the secondary circuit, the pulse width
is adjusted (refer to Fig. on following page).
Secondary rectification of the weld current is performed in the PSG.
6-pole bridge
rectifier
U1
V1
W1
Driver
Power
Controller
supply
to temperature
Control unit
to constant-current
regulation in the PSI
Secondary vol­
tage tapping
*: depending on trans­
Electric Drives
and Controls
3~
1000
Hz
MF inverter
Direct current link circuit
Transistorized transformer-rectifier
U2
U
monitoring
*
*
former design
to electrode gun
| Bosch Rexroth AG 115 / 170
Information on this product
PSG
+
-
Transformer-
Welding
rectifier
equipment
PSI
V2
V
Welding
transformer
PSG
Rectifier