Improvement in accuracy in potential method for detecting EDM spark locations

This paper describes an improvement in accuracy in potential method for detecting EDM spark locations. It is known that the discharge locations can be detected by dividing the feeding wire into two braches and measuring the potential difference between the connecting points and the branching points, which appears at the beginning of the discharge. However, because of the noise of the discharge, good sensitivity for detecting discharge locations is difficult to obtain. In this study, we proposed a method in which the potential difference is measured at the end of the discharge to avoid the influence of the discharge noise. The experimental results showed that a better sensitivity and resolution can be obtained when using the voltage peak value which appears at the end of discharge, compared with the method which uses the difference which appears at the beginning of discharge.