Load-resonant converter with changing resonant tank topology for welding applications

In this paper a new approach and corresponding converter based on varying resonant tank topology for supplying DC loads like welding arc is presented. In order to describe suggested topology the circuitry of proposed converter and some design aspects are discussed in relation to typical load conditions during welding process. Simulation and first experimental data are also provided and analyzed. The obtained natural characteristic of this converter has a constant power mode in the range of welding currents and inherent parametrical short-circuit limitation. Also, its fast “natural” response to change of load conditions could probably yield in better arc stability and more even weld bead quality.