A near zero current switching series resonant inverter using GTOs

The authors present a novel implementation of fast gate turn-off thyristors (GTOs) for a series resonant converter operating above 10 kHz and at an output power rating of 10 kW or greater. A zero current switching gating strategy that eliminates the need of large negative gate drive circuits is presented. This permits the operation of the converter at a near unity load power factor independent of the operating frequency. Consequently, for a given output power, the installed kVA capacity of the converter is minimized, and the system simplicity is maintained. A simplified analysis and component ratings for the GTO-based converter are presented. All the results were verified experimentally