Electronic welder with high-frequency resonant inverter

A new generation of electronic welders, incorporating soft-switched inverters driving high-frequency transformers, is presented. They are light, reliable, and flexible, and offer good efficiency, fast response, and control robustness. A control strategy able to ensure correct operation in any load and supply condition, small stand-by loss, and automatic recovery from line failures is discussed. Experimental results on an industrial prototype rated for 80 V (no-load voltage), 130 A (full-load current), and 80 kHz switching frequency are presented