Research on the Propagation Characteristics of Partial Discharge Signals in 10kV Three-Phase Cable

Currently, damped AC (DAC) voltage technique is extensively used in the field of insulation defect detection for 10 kV distribution cables. However, with the ongoing efforts to improve quality and efficiency in power enterprises, researchers have proposed conducting simultaneous three-phase partial discharge tests during DAC voltage experiments. Yet, the propagation characteristics of partial discharge signals across different phases during simultaneous detection remain under-researched. This paper employs the ATP-EMTP electromagnetic transient software to establish a simulation model, a typical three-phase distribution cable model was established using the LCC module, and a partial discharge source based on the three-capacitor model was positioned in the middle section of the cable. At the connection point between the DAC high voltage output and the three-phase cable, the three-phase partial discharge detection unit facilitates the detection of partial discharge signals across the three phases and isolates the high-frequency signal transmission channels between phases. By analyzing the simulation data from the partial discharge detection, the feasibility and effectiveness of conducting simultaneous three-phase partial discharge testing during DAC testing have been validated.