Research on energy saving EDM pulsed power supply with cyclically superimposed chopper circuit

This paper presents an energy saving electrical discharge machining (EDM) pulsed power supply, the principle of which is introduced. This pulsed power supply possesses no current-limiting resistors used in conventional EDM pulsed power supplies and no energy storage inductors applied in most other energy saving pulsed power supplies. Direct current from DC power supply is chopped to form many branches of paralleling spike pulse currents and the current branches are then combined into the desired pulse current for EDM machining through cyclic superimposition. The calculation method of energy loss is then analyzed. The short-circuit and contrastive machining experiments proved that the new pulsed power supply was capable of performing stable machining with higher machining efficiency and less main-machining-circuit energy loss than those of conventional EDM pulsed power supplies.