中文摘要：

为解决变压器现用矿物绝缘油资源短缺和环境污染等问题，在前期研究的基础上，研制了一种矿物油-天然酯混合绝缘油。实验表明该混合油在各项指标上均满足变压器用油的标准，并通过热老化实验初步证实了该混合油具有较矿物绝缘油优良的抗老化性能。为探索该混合油及其浸渍的绝缘纸与普通矿物油-纸绝缘在热老化特性上的差异，对矿物油-纸绝缘和混合油-纸绝缘在110℃下开展了264天的加速热老化实验，对比分析了老化过程中2种绝缘油的酸值、颜色和绝缘纸聚合度的变化规律。结果表明，该混合油能有效延缓由其浸渍的绝缘纸的热老化速率。最后在物质分子结构和材料热稳定性层面揭示了混合油-纸绝缘抗老化的机制，为该混合油的下一步研究工作和工程应用奠定了基础。

英文摘要：

To deal with the shortage of mineral insulating oil used for transformers and the related problem of environmental deterioration, a new type of mixture insulating oil composed of mineral oil and natural ester has been developed through a plenty of research work. It was proved that the mixture insulating oil has excellent electrical and physicochemical properties, which meet the standard of transformer insulating oil. The thermal aging experiment indicated that the anti-aging effect of the mixture oil is better than that of the traditional mineral oil. In order to explore the difference in thermal aging characteristics between mixture oil-paper insulation and mineral oil-paper insulation, a 264-day test on thermal aging acceleration was performed under 110℃. Comparative analyses were conducted on acid values, colors of the oils, as well as the degree of polymerization of insulation papers. Results showed that the anti-aging property of the mixture oil is superior to the mineral oil. In addition, the mixture oil can effectively delay the thermal aging rate of the impregnated insulation papers; and the mechanism can be explained at the level of molecular structure and thermal stability of materials, so as to provide a theoretical basis and a technical support for further research and engineering application of the mixture oil.