Design of Bio-Based Epoxy Insulating Spacers for Eco-friendly Gas-Insulated Switchgear Applications: Structural and Mold Flow Analysis

Various insulating components in power equipment have traditionally been manufactured using petroleum-based epoxy resins, which contribute to resource depletion and greenhouse gas emissions. To address sustainability, bio-based epoxy composites have emerged as promising alternatives because they utilize atmospheric CO₂ fixed through photosynthesis. In this study, bio-based epoxy composite insulating spacers for gas-insulated switchgears (GISs) are designed and fabricated. Finite element method (FEM) simulations are performed to evaluate structural integrity, and the automated pressure gelation (APG) molding process is optimized using Autodesk Moldflow thermal–fluid analysis to ensure uniform resin flow and minimize defects. Spacers fabricated under the optimized APG conditions are subjected to a series of evaluations. Non-destructive tests, including X-ray inspection, thermal cycling, and dye penetrant analysis, confirm the absence of voids, cracks, or metallic impurities. Hydrostatic pressure burst tests demonstrate that both bio-based and conventional petroleum-based epoxy spacers withstand pressures exceeding three times the design specification. Furthermore, the maximum stress experienced during simulated operation is lower than the tensile strength of the bio-epoxy (64.4 MPa), and the deformation rate remains below 1%, ensuring mechanical safety. These results verify that bio-based epoxy spacers satisfy the mechanical and dielectric requirements for GIS applications. The study highlights the feasibility of replacing petroleum-based resins with bio-based epoxy composites, thereby enabling eco-friendly high-voltage insulation components for next-generation sustainable power equipment.