Fabrication and Electrical Withstand Performance Investigation of Stereolithography-Based Dielectric Functionally Graded Insulators

The gas-solid interfaces formed by solid insulation and gas atmosphere are weak links in the insulation of electrical equipment. They are prone to surface flashover or breakdown, leading to accidents that severely affect the safe and stable operation of power systems. In recent years, the construction of dielectric functionally graded insulation (d-FGI) has become an effective solution to address this issue. This paper employs an iterative algorithm to optimize the spatial distribution of permittivity for d-FGIs in truncated cone insulators and analyzes the comprehensive influence of various parameters on the electric-field optimization effect. The optimization results show that the maximum surface electric-field strength of the graded insulators can be reduced by over 70% under ideal conditions, indicating a significant optimization effect. Photosensitive resin-based dielectric-grade insulators were prepared using stereolithography 3D printing technology. Flashover voltage tests were conducted on the photosensitive resin-based graded insulator samples. The results demonstrate that under 0.4 MPa SF₆ gas, the flashover voltage of photosensitive resin-based dielectric graded insulators can be increased by up to 22.46% compared to pure photosensitive resin insulators, showing a notable improvement in electrical performance.