Cable Oscillating Wave Partial Discharge Detection

By applying an attenuated oscillating wave voltage close to power frequency to the test cable, partial discharge signals at insulation defects are excited, effectively detected, and located to determine the insulation condition of the cable. Based on the LCR damped oscillation principle, after DC charging the cable, an internal high-voltage reactor, a high-voltage real-time solid-state switch, and the test cable form a damped oscillating voltage wave. Software is used to display the partial discharge signals occurring at weak insulation points of the cable and its joints in a regular pattern. By analyzing the waveform data, the discharge magnitude of partial discharge can be measured and the discharge point can be accurately located. The software can also control the damped oscillation waveform to repeat multiple times, making verification of cable insulation defects more reliable. Throughout the test, there is no static electric field in the cable specimen, no space-charge accumulation effect on cross-linked polyethylene cables, and no damage to the insulation.