voestalpine Böhler Welding

Power sources for electric arc welding

28. mar 2017

Welding rectifier
A welding rectifier converts three-phase current (AC) into DC for welding. It consists of a power transformer and a downstream rectifier.

Welding transformer
In the welding transformer, the network’s AC current with its high voltage and low current level is converted to AC current with low voltage and high current level as is needed for welding. The welding current is regulated by tapping the primary coil of the power transformer.

Welding inverter
The welding inverter is an electronic welding current source. Depending on the needed power, the inverter is connected to one-phase or three-phase power. First the supply voltage is rectified, then a power semiconductor is used to bring it back to alternating current with a frequency between 20 kHz and 150 kHz and a relatively small transformer transforms it to a low voltage. Finally, the welding current is rectified using suitable diodes. The result is a high power direct current with a low voltage.


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