Using HFCT for compliant PD measurements

The measurement and monitoring of some important parameters characteristic for the electric power equipment health evolution, from the moment of leaving the manufacturing company and throughout the active life, are contained in the standards in the field and followed carefully by the utilities. The paper deals with issues related to the accurate measurement of Partial Discharges (PD) level in the most different insulation systems and, particularly, with the consistent evaluation of the characteristics of measuring impedances used for PD signal acquisition. Lately, wideband High Frequency Current Transformers (HFCTs) are more and more used instead of the classical RLC measuring impedance provided in the basic IEC 60270 standard due to their ease of installation and high signal/noise ratio,…