A New Pulse Discriminating System for Micro-EDM

A new pulse discriminating technique for monitoring microelectrical discharge machining (micro-EDM) process in real time is proposed. The proposed system employs current pulse as the main detecting parameter as it is considered to be a better representation of the spark energy inside plasma channel as compared to the voltage. Micro-EDM pulses are classified into normal discharge, delayed discharge, arcing, and short circuit. The developed system was tested on micro-EDM drilling and micro-EDM milling, and the pulse distributions throughout these processes were analyzed. The developed pulse discriminator (PD) system is further used in the development of an adaptive speed servo system in micro-EDM. Experiment results show that the system is able to improve the machining time by more than 50%, and the accuracy of the resulting features is increased.