Partial discharge experiences in HV grids applying wideband measurements

Different partial discharge (PD) measuring techniques have been developed in the last years specially designed to perform on-site and on-line measurements. When on-line PD measurements are performed in noisy environments or when more than one source of pulse-shaped signals is present in the test object, in many cases it results very difficult to perform a correct diagnosis. In order to provide reliable high level indicators of the insulation status, some challenges like noise discrimination, PD location and pattern identification have been considered in this study. Some practical experiences about on-line PD measurements in high voltage (HV) grids are presented. These PD measurements were addressed to improve the electrical system reliability using a modern measuring device operating in wideband frequencies. Insulation defects were found in time to avoid uncontrolled failures in the power grid.