植物绝缘油作为一种高燃点、可降解的环保液体电介质,被普遍认为是矿物绝缘油的良好替代品。目前,植物绝缘油已在配电变压器中得到良好应用,并逐步开始应用在大型电力变压器中。介绍了植物绝缘油及其应用研究的历史与现状,分析了植物绝缘油在制备方法、电气与理化特性以及植物油纸绝缘寿命模型和植物绝缘油变压器故障诊断方法等方面取得的进展。通过对关键问题的分析,说明了植物绝缘油相比矿物绝缘油具有的一些新的优点。植物油纸绝缘可有效延缓绝缘纸的老化速率,通过良好的变压器设计和运行维护,植物绝缘油可提高变压器的过负荷能力,植物绝缘油变压器将比矿物绝缘油变压器具有更低的全寿命周期成本。最后,提出了植物绝缘油及其应用在未来研究中,应重点关注植物绝缘油化学及纳米改性、油中长间隙放电、植物绝缘油变压器运行维护和纳米植物绝缘油等方面的关键问题。
Vegetable insulating oils are environment-friendly and biodegradable liquid dielectrics with good insulation properties, and have been generally considered as substitutions of mineral insulating oils. The transformer industry is experiencing a good application of vegetable insulating oils in distribution transformers and rapidly increasing use in large power transformers. The authors introduce the current research on the vegetable insulating oils and vegetable oil transformers, and analyze the principle problems involving preparation of vegetable insulating oils, dielectric and physicochemical properties, lifetime models of vegetable oil-paper insulation, and fault diagnosis for vegetable insulating oil-filled transformers. Several new points that vegetable insulating oils take advantages to mineral insulating oils, are concluded through the analysis. Through proper design and maintenance, vegetable insulating oil are capable of increasing residual life of oil-paper insulation,enhancing over-load ability of oil-filled transformers, reducing life-cycle expenses of oil-filled transformers. Finally, the authors raise the issues about future research on vegetable insulating oils and their applications, mainly focusing on chemical and nano modification of vegetable insulating oils, breakdown of long gap in vegetable insulating oils, maintenance of vegetable insulating oil transformers, and vegetable insulating oil based nanofluids.