For studying the harmonic component characteristics of the loss current in case of conductor spike defect in the 35 kV XLPE cable

the simulation model of the conductor spike defect of 35 kV XLPE cable is constructed based on the theory of jump conductance in this paper

the influence of radius of spike curvature

the location of the spike and electrode distance on the loss current harmonic characteristic is simulated and analyzed. Then

a sample of conductor spike defect in 35 kV XLPE cable is made

and the verification experiment under the condition of radius of spike curvature at 30 mm

spike at the shielding layer and the electrode spacing of 3 mm is performed. Both simulation and experimental results show that in case of conductor spike defect in the 35 kV XLPE cable

the distorted high strength electric filed at the defect place will make the conductivity characteristics of the XLPE to generate periodic fluctuation with alternating AC voltage

causing distortion of the waveform of the loss current and superposition of high-order harmonic components. From the perspective of harmonic components

the significant 3rd and 5th harmonic components in the loss current are existed. The severity of defects varies depending on their locations

and the contribution rates of 3rd and 5th harmonics are also different. The harmonic distortion rate of loss current and conductivity distortion rate of the conductance are inversely proportional to the curvature radius of the spikes and the electrode spacing

and the distortion rates of both are higher when the spikes are located in the wire core than when they are located in the shielding layer.