Gap current voltage characteristics of energy-saving pulse power generator for wire EDM

The characteristics of the gap current voltage are directly used to estimate the gap status and are helpful in understanding the gap discharge mechanism and in adjusting the process parameters in wire electrical discharge machining (WEDM). Current and voltage waveforms were studied to analyze the gap current voltage characteristics of an energy-saving pulse power generator during a discharge pulse period. The discharge voltage was increasing with discharge time, and the gap current waveform was triangular other than the traditional rectangular waveform. A gap detection model of the energy-saving pulse power generator was established to analyze further the gap current voltage characteristics theoretically. Experiment analysis of different workpiece materials and current peak values showed that the gap discharge voltage and short circuit voltage continuously increase. The triangular waveform and increasing discharge voltage were caused by the increasing gap current in the process because the sustaining voltage was absent in the discharge status. And the gap current voltage characteristics were nonlinear.