Regenerative clamp as reset winding in flyback converters for EDM applications

Switch mode power supplies in electrical discharge machining (EDM) applications remove the need for bulk output capacitors. The switch mode converter topology investigated in this paper is the flyback converter. The operation of the flyback topology without bulk output capacitors requires resetting the flyback transformer. In this paper, the absence of the reset mechanism and two approaches to reset the flyback transformer are investigated. The traditional RC clamp will only be an effective reset mechanism if the resistor is reduced to a very small value which will lead to higher power losses and will not be suitable for this application. The application of a reset winding similar to forward converters may be utilized; however, the need for a turn off snubber is not eliminated. A regenerative clamp used in flyback converters will act as a reset winding and as a turn off snubber. The use of this configuration is proposed for EDM applications.