Multi‐Layer Charge Regulation Engineering for Efficient Enhancement of Aramid Epoxy‐Based Composite at Withstand Voltage Performance

In recent years, fiber‐reinforced epoxy resin‐based composites have become commonly used for insulating components in high‐voltage transmission and transformation equipment. The high withstand voltage performance of materials is crucial to ensuring the safe and stable operation of equipment and the power grid. Therefore, in this paper, a multi‐layer charge regulation engineering was designed on the aramid fiber's surface to regulate the distribution and transmission of charges, thereby achieving an efficient enhancement of the withstand voltage of the composites. This engineering utilizes the charge trapping characteristics of insulating materials and the charge transport properties of semiconductor materials. The effectiveness of this engineering was validated through the tests of flashover voltage and breakdown strength. After constructing the optimal multi‐layer charge regulation structure, the flashover voltage increased by 62.03%, and the breakdown strength improved by 65.22%. Combining charge dissipation and trap distribution, interface bond strength, molecular dynamics simulations, and phase‐field modeling results reveals the mechanism of the multi‐layer charge regulation engineering. This can be summarized as the charge trapping in the F‐Group layer, uniform charge distribution in the ZnO nanowire layer, and deep charge transport in the FePc layer, which together ensure the effective enhancement of the material's withstand voltage performance.