Effect of Doping Microcapsules on Typical Electrical Performances of Self-Healing Polyethylene Insulating Composite

Abstract

Polyethylene cables, as important transmission equipment of modern power grid, would inevitably be slightly damaged, which seriously threatens the safety of the power supply. This paper has pioneered the preparation and typical performances of a self-healing polyethylene insulating composite. The self-healing performance to structural damage was verified by tests of electrical and mechanical damage. The effect mechanism of doping microcapsules on the electrical performance of polyethylene was emphatically analyzed. The results show that in appropriate conditions (such as 60 • C/30 min), the composite can not only repair the electrical tree and scratches, but also restore the insulation strength of damaged area. The effect of doping microcapsules on the electrical performances of polyethylene, such as breakdown strength, volumetric resistivity, dielectric properties, and space charge characteristics, are mainly related to impurity and the interface of microcapsule. Polarization and ionization of impurities can reduce the electrical performance of polyethylene. The interface not only improves the microstructure of polyethylene (such as how the heterogeneous nucleation effect increases the number of crystal regions, and the anchoring effect enhances the stability of amorphous regions), but also increases the charge traps. Moreover, the microstructure and charge trap can affect the characteristics of carrier transport, material polarization, and space charge accumulation, thus improving the electrical performance of polyethylene. In addition, the important electrical performance of the composite can meet the basic application requirements of polyethylene insulating material, which has good application prospects.

Self-Healing of Materials under High Electrical Stress

“…Methods to self-heal such electrical trees include intrinsic mechanisms 22,23 and extrinsic approaches. 2,24,25 Intrinsic self-healing properties of trees have been reported in several materials systems, such as cross-linked polyethylene, 22,26 silicone gels, 27,28 silicone rubbers, 29,30 and polymer composites, 31 which are discussed in more detail later.…”

“…ll Matter 3, 989-1008, October 7, 2020 995 Perspective Self-Healing of Electrical Insulation Self-healing has been used as electrical insulation protection for both high AC and DC conditions, and combinations of AC and DC stress. Intrinsic 22,23 and extrinsic 24,25,33,44 approaches to heal electric treeing have been considered; fluidfilled cables have also been used. 45,46 Potential applications include reliable and durable insulation for high-tension transmission cables, high-voltage electronics, and robotics.…”

Evaluation of dielectric strength of SiR/TiO 2 composites using feed‐forward neural network

“…The decrease in the electrical performance of SiR can be due to the polarisation and ionisation of impurities. The interface not only improves the structure of SiR but also increases the traps, which can enhance the dielectric performance of SiR [21].…”

Repair Performance of Self-Healing Microcapsule/Epoxy Resin Insulating Composite to Physical Damage

“…According to the relevant literature [16,25] and my previous work (as shown in Table 1), the important basic properties (such as thermal stability, Young's modulus and tensile strength) of composite with about 1 wt. % microcapsule are more in line with the application requirements of epoxy resin insulating material.…”

“…On the one hand, the local state formed by the interface structure can anchor the macromolecular chains in the matrix material, improving the stability of matrix structure [25]. And the stable internal structure can hinder the invasion of external factors (such as thermal factor).…”