Evaluation Of Partial Discharge Measurement Circuits And Associated Calibration Techniques

This paper presents an evaluation of the RIV circuits used for the measurement of partial discharges. The results show that the NEMA 107-1964 RIV circuit, as presently used in high voltage laboratories, does not consider the entire calibration problem. The test circuit can produce resonance at a particular frequency, the choke coils can create a resonance shift, and the capacitance from the bottom end of the coupling capacitor to ground is significant. This capacitance, combined with the coupling capacitor and inductance of the conductor, forms a resonant circuit at the measurement frequencies.