Location of Partial Discharges in Power Transformers by Computation and Measurement of Capacitively Transmitted Voltage Pulses

The voltage distribution in a power transformer after a partial discharge has occurred is calculated. The results are compared with voltages, measured at the terminals of the transformer. A partial discharge prediction curve, based on the calculated capacitive distribution is constructed, by which the location of partial discharges is improved. The location method is based on peak values or capacitive pulses measured at the terminals. Calculation of the complete winding resonances after a partial discharge is found not to be accurate enough for internal corona location purposes.