Evaluation and Analysis of Gassing Material Performance Used in Low-Voltage Circuit Breakers

This paper introduces an evaluation method for gassing materials used in low-voltage circuit breakers and identifies key factors affecting arc characteristics. Firstly, sixteen types of gassing materials were prepared using PA6 and PA66 as matrices, with various flame retardants and reinforcements as additives. Breaking experiments were conducted in both low-frequency and direct-current circuits to assess these materials in terms of arcing and post-arc phenomena. Material characterization techniques were then employed to analyze the optical absorption and pyrolysis properties of the selected gassing materials. Finally, based on the physical mechanisms of interaction between arcs and gassing materials, a detailed mechanistic analysis and theoretical explanation were provided, integrating material characterization and microscopic modeling. The results suggest that the proposed evaluation method effectively identifies one or two materials with optimal overall performance from the 16 types tested. Superior materials are characterized by organic molecular fillers and high radiation absorption, which enhance arc energy absorption and increase ablation gas generation. Hydrogen-containing gases (e.g., H₂, CH₄, H₂O) and gases with high dissociation energy (e.g., CO₂, N₂) are crucial for arc extinction. This paper also highlights two major challenges facing current gassing materials, suggesting areas for further research.