Preparation and mechanism of charge carrier transportation of MsO/LDPE nanocomposites

With the development of high-voltage direct current (HVDC) transmission, LDPE nanocomposites have attracted more attention for fabricating HVDC cables instead of oil-filled cables and mass impregnated cables. However, the HVDC cable insulating materials with high-performance electrical properties are urgent to realize and the mechanism of charge carrier transportation is still unclear. In this work, LDPE nanocomposites filled with multi-layer structure MgO was prepared by means of melt blending. As the MgO is considered as the ideal nanofillers owing to execellent electric properties in dc materials. Few studies have reported the special structure of nanofiller on suppressing space charge and mechanism of charge carriers transportation. The multi-layer structure MgO was prepared through a solvothermal method, which is low density, high aspect ratio. The microstructures, as well as the space charge distribution and thermally stimulated current (TSC) were studied. The mechanism of charge carrier injection and transportation in MgO/LDPE nanocomposites under HVDC transmission condition were also explored. Results showed that the multi-layer structure of MgO nanoparticles were homogeneously dispersed in LDPE matrix, which enhanced the overall electrical properties of the MgO/LDPE nanocomposites. Moreover, the hypothesis model of charge carrier transport in solid dielectrics coupling with experimental results were used to explore the mechanism of charge carrier injection and transportation under HVDC condition.