Implementation of statistical capabilities into a digital acquisition and processing system for partial discharges

A 2-channel data acquisition and processing system (DAPS) for partial discharges (PD) using a fast (20 MSa/sec) digitizer has been developed which can acquire up to 16 MSa per channel, and simultaneously measure the phase ´φ´ and ´q´ of PDs occurring on a given power line voltage and represent on a 3D plot of n(q,φ). This system has been tested using artificially generated PD pulses and experimental data. The resolution of this DAPS system is 50 mV in voltage and 1° in phase. A statistical package has been added to the processing of the data so that a distribution identification test of the PD pulse heights can be performed. In this process, the first four moments of the experimental pulse height distribution are obtained and from these moments, two parameters β₁ and β₂ are calculated. These parameters are used to identify the underlying distribution.