Instantaneous root mean squire value of the acoustic emission as a means of measuring partial discharges

The author presents the measurement results of the parameter A _RMS for three types of partial discharges (PDs) generated in a typical high-voltage system: on pressboard, on resin, and on glass. A typical run of A_RMS on an X-Y register is shown. It manifests a relatively stable instantaneous root mean square value of the electric signal converted from the acoustic signal as a function of time. Results obtained for the three surfaces demonstrate that the parameter A_RMS is perfectly suitable for characterizing PDs measured by the acoustic method. It is univocally connected with the energy of the generated PD