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OA
Study on Key Performance Variations and Pyrolysis Mechanisms of Multicomponent Mixed Insulating Oil Under Lightning Impulse Breakdown
为揭示多元混合绝缘油在雷电冲击击穿后的关键性能劣化规律及微观裂解机理,搭建了雷电冲击击穿试验平台,测试了不同油隙条件下油品的理化性能、介电性能及溶解气体体积分数,并基于ReaxFF反应力场开展了分子动力学模拟,分析了击穿放电产生的高温强电场耦合作用下油分子的裂解路径与特征气体生成机制.结果表明:随油隙增大,击穿后油品性能劣化加剧,其中酸值增幅最为显著,长间隙条件下较初始值升高近190%,可作为冲击老化程度的敏感指标;介质损耗因数与体积电阻率在长间隙下分别劣化约53%和40%,颗粒浓度显著增加且集中于5～15 μm粒径范围;H2与C2H2为主要特征气体,其体积分数随放电能量增加持续上升.分子模拟表明,低电场下裂解以单键逐步断裂为主,强电场通过增强分子极化和化学键断裂概率加快裂解过程并诱发芳香烃开环反应,但特征气体生成路径仍遵循传统热裂解机制.研究结果可为多元混合绝缘油的工程应用及绝缘状态评估提供理论依据.
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.
刘梦娜;刘熙;刘熊;杨旭;周正钦;王谦;叶文郁
国网电力科学研究院武汉南瑞有限责任公司,武汉 430074||南瑞集团(国网电力科学研究院)有限公司,南京 211000国网电力科学研究院武汉南瑞有限责任公司,武汉 430074||南瑞集团(国网电力科学研究院)有限公司,南京 211000国网重庆市电力公司,重庆 400014国网电力科学研究院武汉南瑞有限责任公司,武汉 430074||南瑞集团(国网电力科学研究院)有限公司,南京 211000国网电力科学研究院武汉南瑞有限责任公司,武汉 430074||南瑞集团(国网电力科学研究院)有限公司,南京 211000国网重庆市电力公司,重庆 400014重庆大学电气工程学院输变电装备技术全国重点实验室,重庆 400044
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
multi-component mixed insulating oillightning impulsegas generation characteristicspyrolysis mechanismreactive molecular dynamicsdielectric performancetransformerperformance evolu-tionmechanism
《高压电器》 2026 (9)
79-88,107,11
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).
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