Partial Discharge Characteristics of 10kV Power Cable Defects under Very Low Frequency Voltage and Oscillating Wave Voltage

Both very low frequency voltage and oscillating wave voltage are applied to the partial discharge detection of power cable. In order to compare the partial discharge characteristics of power cable defects under very low frequency voltage and oscillating wave voltage, 10kV heat-shrinkable, cold-shrinkable power cable samples with axial and radial knife marks defects, with water-intake defect and with no defect were respectively tested under very low frequency and oscillating wave voltage. Partial discharge tests were carried out, and the partial discharge inception voltage, maximum partial discharge volume and partial discharge waveform were measured and recorded. The test results show that the partial discharge inception voltage of 10kV power cables under the oscillating wave voltage is lower than that of the very low frequency voltage. Under the same fixed voltage, the maximum partial discharge of the oscillating wave voltage is larger, the number of partial discharge pulses is more, and the partial discharge waveform is more dense than that of the very low frequency voltage.