Insulation Property Researches of Aged PVC Cables by the Polarization-Depolarization Current Method
The aging of electrical cables could lead to insulation breakdown,culminating in short circuits and even the occurrence of fire incidents.To investigate the insulating properties of low-voltage cables after aging,accelerated aging experiments were conducted on the polyvinyl chloride(PVC)insulation material used in the cables.Analysis of the polarization-depolarization current data from the samples revealed the change patterns in parameters such as DC conductivity and low-frequency dielectric loss factors.Furthermore,the physicochemical properties of the aged samples were assessed through thermogravimetric analysis and Fourier infrared spectroscopy.The results indicate that with the increase of aging time,there is a notable augmentation observed in parameters including polarization current,depolarization current,conductivity,and low-frequency dielectric loss factor.The thermal gravimetric analysis and Fourier transform infrared spectroscopy results further elucidate that the long-term high-temperature aging reduces the chlorine content of PVC cable insulation,diminishing the flame retardancy and resulting to the fracture of PVC molecular chains.The contents of functional groups such as hydroxyl,methyl,methylene,and carbon-carbon double bonds increase.These alterations exacerbate the cable aging,ultimately decreasing the insulation performances of cables.
Polarization-Depolarization Current MethodPolyvinyl Chloride CablesInsulating PropertyConductivityLow-frequency Dielectric Loss
万方数据
维普
