高压电器2026，Vol.62Issue(9)：79-88,107,11.DOI:10.13296/j.1001-1609.hva.2026.09.009
雷电冲击击穿下多元混合绝缘油的关键性能变化及裂解机理研究
Study on Key Performance Variations and Pyrolysis Mechanisms of Multicomponent Mixed Insulating Oil Under Lightning Impulse Breakdown
摘要
Abstract
To reveal the key performance degradation behavior and the microscopic pyrolysis mechanism of multi-component mixed insulating oil after lightning impulse breakdown,a lightning impulse breakdown test platform is established.The physicochemical properties,dielectric performance,and dissolved gas content of the oil samples are tested under different oil-gap conditions.Furthermore,molecular dynamics simulations based on the ReaxFF re-active force field are conducted to analyze the pyrolysis pathways of oil molecules and the formation mechanisms of characteristic gases under the coupled effects of high-temperature and strong electric field generated by the break-down discharge.The results show that with increase of oil gap,the performance degradation of the oil samples after breakdown becomes more severepronounced.Among all parameters,the acid value exhibits the most significant in-crease,rising by nearly 190%compared to the initial value under long-gap conditions,which can serve as a sensi-tive indicator of impulse aging degree.Under long-gap conditions,the dielectric dissipation factor and volume resis-tivity deteriorate by approximately 53%and 40%,respectively,while the particle concentration increases significant-ly and is mainly distributed in the 5～15 μm size range.The H2 and C2H2 are identified as the main characteristic gases,and their contents increase continuously with increase of discharge energy.The molecular simulation indi-cates that under a low electric field,pyrolysis is dominated by stepwise single-bond scission,while a strong electric field accelerates the pyrolysis process by enhancing molecular polarization and increasing the probability of chemi-cal bond cleavage,and also induces ring-opening reactions of aromatic hydrocarbons.However,the formation path-ways of characteristic gases still follow conventional thermal pyrolysis mechanisms.The study results can provide a theoretical basis for the engineering application and insulation condition assessment of multi-component mixed insu-lating oil.关键词
多元混合绝缘油/雷电冲击/产气特性/裂解/反应动力学/变压器/性能演化/机理Key words
multi-component mixed insulating oil/lightning impulse/gas generation characteristics/pyrolysis mechanism/reactive molecular dynamics/dielectric performance/transformer/performance evolu-tion/mechanism引用本文复制引用
刘梦娜,刘熙,刘熊,杨旭,周正钦,王谦,叶文郁..雷电冲击击穿下多元混合绝缘油的关键性能变化及裂解机理研究[J].高压电器,2026,62(9):79-88,107,11.基金项目
国家电网公司总部科技项目(5500-202327118A-1-1-ZN). Project Supported by Science and Technology Project of State Grid Corporation of China Headquarters(5500-202327118A-1-1-ZN). （5500-202327118A-1-1-ZN）
