A novel squarewave inverter for high-output-current applications

A novel squarewave current inverter suitable for arc welding is proposed in this paper. Current-steering diodes connected across the output chokes keep the inductor current continuous and retain the energy during the commutation period. The commutation time can thus be reduced to ensure a better welding performance. Also the stored energy can be released in the next energy transfer cycle to raise the conversion efficiency. The circuit operations and design procedures are examined thoroughly. Experimental results on a prototype inverter for driving a 100-A AC arc welding machine are recorded to validate the effectiveness of the presented scheme.