Laboratory Calibration of HFCT Partial Discharge Detection Systems

With the advantages of high sensitivity and non-intrusiveness, HFCT PD detection systems are implemented in order to monitor incipient faults of power cables. This paper introduces a laboratory calibration method for HFCT PD detection systems based on a Gauss pulse signal. In order to modify practical PD signal at 1MHz~30MHz frequency band, equivalent Gauss pulse signal with certain rise time is applied. The method overcomes the drawback of sensitivity verification method recommended by IEC 62478 in traceability. All the standard equipment applied is frequently-used device in electrical laboratory. Parameters of the calibration work include frequency band, amplitude linearity, transfer impedance and detection sensitivity. By analyzing the data of four systems, the calibration provides reasonable criteria in quality verification of HFCT PD detection systems.