A Novel Short Neutral Section Design Featuring Self-Rotating Rollers for Reduced Wear and Improved Performance in Railway Overhead Power Transmission Systems

This paper presents a novel Short Neutral Section (SNS) design for railway overhead power transmission lines. Finite element analysis (FEA) was used to analyse both its electrical and mechanical performance. The SNS isolates different power phases and facilitates smooth pantograph transfer without lowering. Traditional designs use PTFE rods, requiring frequent rotation due to wear (every 2 mm), making them highly maintenance intensive. This work proposes a matrix of PTFE roller, achieving lower wear by leveraging self-rotation when coming in contact with a moving pantograph. The authors evaluated the new design's electrical performance using FEA. Parameters like dry arc and creepage distances were optimized for optimal performance. Additionally, FEA was used to verify the mechanical performance, with the results compared to in-house experimental data of the developed prototype. Two constraint methods were investigated, and the one with closer results to experiments was chosen for further analysis. The design with two GFRP rods arranged in a parallel vertical configuration emerged as the most mechanically robust, displaying minimal bending and total deflection below 7 mm under eccentric loading.