含分布式光纤的变压器油老化寿命评估研究

Ageing Lifetime Evaluation of Transformer Oil Containing Distributed Optical Fiber

为探索分布式光纤对变压器绝缘系统老化寿命的影响,对含分布式光纤变压器油样在110、120、130℃下进行加速热老化试验,在热老化期间定时取样并测试击穿电压,然后基于击穿电压累积损失率,分析含光纤变压器油活化能与纯油活化能的关系,并提出一种含光纤变压器油活化能的计算方法,构建含光纤变压器油的热老化寿命模型。结果表明:变压器油中内置光纤会影响变压器绝缘系统的强度,乙烯-四氟乙烯共聚物(ETFE)光纤对变压器油的老化影响最小;基于计算活化能与击穿电压累计损失动力学方程建立的含ETFE、聚四氟乙烯(PTFE)、热塑性聚酯弹性体(TPEE)光纤变压器油的3个寿命评估模型的计算结果与工程经验中的10℃寿命准则的评估结果较为吻合,验证了模型的有效性。

In order to explore the influence of distributed optical fiber on the ageing life of transformer insulation system, we carried out accelerated thermal ageing tests on the transformer oil sample containing distributed optical fiber at 110, 120, 130℃. The breakdown voltage of the samples was measured regularly during thermal ageing process. On the basis of the breakdown voltage cumulative loss rate, the relationship between the activation energy of the transformer oil containing optical fiber and pure oil was analyzed, a method for calculating activation energy of transformer oil containing optical fiber was proposed, and a thermal ageing life model of transformer oil containing optical fiber was constructed. The results show that the optical fiber in the transformer oil can affect the strength of the transformer insulation system, and the ethylene tetrafluoroethylene(ETFE) optical fiber has the least effect on the ageing of transformer oil. The calculated results of three life evaluation models of transformer oil containing ETFE, poly(tetrafluoroethylene)(PTFE), and thermoplastic polyester-ether elastomer(TPEE) fiber established based on calculated activation energy and breakdown voltage cumulative loss kinetic equation, are in good agreement with the evaluation results of 10℃ life criterion in engineering experience, which verifies the effectiveness of the model.