LORCH V Series - Inverter Principle; Welding Inverter Structure

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Inverter Principle
A welding inverter is a electronically controlled welding power source. At conventional transformer based ma-
chines, the mains voltage with 50/60 Hz is directly switched to the welding transformer. At a welding inverter the
mains voltage is rectied rst and with electronic power switches (MOSFETs or IGBTs) chopped into a frequency
of 80 kHz. This allows a very small construction of the welding transformer, because it‘s driven at this high fre-
quency. The basic structure of a welding inverter is always the same at Lorch power sources:
- mains rectier
- primary inverter
- transformer
- secondary rectier
mains
filter
3 phase mains
input
rectifier
primary
driver
transformer
secondary
rectifier
power
up