Structural Design and Electromechanical Performance Verification of High-Voltage Optical Fiber Composite Insulators Based on Finite Element Simulation

Silicone rubber optical fiber composite insulators introduce interface defects due to embedded optical fibers, and their structural design remains immature, resulting in inadequate interface sealing performance. In actual operation, the combined effects of high electric fields, high humidity and heat, and mechanical loads lead to frequent failures. This study proposes replacing conventional silicone rubber with cycloaliphatic epoxy resin (CEP), which exhibits superior aging resistance, to enhance long-term operational reliability. However, the correlation mechanism between the structural parameters of CEP optical fiber insulators and their electromechanical properties remains unclear, lacking corresponding design basis. Therefore, based on finite element simulation technology, this study systematically analyzed the influence patterns of core rod diameter, fiber implantation method, spiral groove angle, fiber implantation quantity, and voltage equalization ring structural parameters (outer diameter, circular tube radius, shielding depth) on their mechanical and electrical properties. Research findings indicate that in terms of mechanical properties, the helical groove structure with a 40 mm core rod diameter, a groove angle of 135°, and six embedded optical fibers exhibits the lowest optical fiber strain. In terms of electrical performance, the minimum peak electric field strength at the end of the insulator occurs when the equalizing ring has an outer diameter of 370 mm, the circular tube radius is 25 mm, and the shielding depth is 50 mm, reaching only 4.6 kV/cm, which meets the requirements of DL/T 1000.3-2015. This study establishes optimization principles for key structural parameters of CEP optical fiber composite insulators, offering significant engineering value for enhancing the overall performance of optical fiber composite insulators and improving the operational safety of power systems.