Current mode controlled LCC resonant converter for electrical discharge machining applications

In this paper, a contribution to the electrical discharge machining (EDM) technology is presented. The final aim of this research is to develop small size EDM systems and determine the influence of the voltage and current of the output electrical arc on the quality and efficiency of the workpiece machining. The proposed system is a DC to DC LCC resonant converter intended to generate current controlled arc pulses at a constant frequency that erode the workpiece. The benefits of this proposal are: (1) the system has inherent protection under short circuit; (2) a simple linear controller results in a highly robust feedback control under load changes; and (3) the transistors turn-on at zero voltage is guaranteed at any load value. The output voltage is intended to be adjusted by an external system that controls the arc distance.