基于Wiener模型的变压器油纸绝缘老化剩余寿命评估方法

Residual Life Assessment Method of Transformer Oil-Paper Insulation Aging Based on Wiener Modle

变压器的稳定安全运行是电网可靠供电的重要保证,为合理预测实际运行单台变压器油纸绝缘的剩余使用寿命,提供一种单台变压器油纸绝缘系统剩余使用寿命的预测方法。首先以Wiener随机模型为理论基础,建立其剩余概率密度函数方程;其次利用Bayesian定则对参数进行迭代更新处理,并采用最大期望算法,实现剩余寿命预测模型参数迭代更新,最终达到剩余寿命预测的目的。为进一步验证上述剩余寿命预测方法的准确性,在实验室中进行130℃加速热老化试验,分别获得老化温度下的油中糠醛退化数据及绝缘纸板聚合度退化数据,将退化数据与上述算法相结合,对比实测油纸绝缘剩余寿命的结果,验证了所提算法预测变压器油浸纸板剩余寿命的准确性。

The safe and stable operation of the transformer is an important guarantee for reliable power supply.In order to reasonably predict residual life of oil paper insulation for single transformer in actual operation.This paper provides a prediction method for residual life of oil-paper insulation system of single transformer.Firstly this paper selects the Wiener stochastic model as the theoretical basis.And the residual probability density function equation is established.Secondly the Bayesian rule is used to update the parameters in real time.Meanwhile,the EM algorithm is used to update the iteration parameter.Finally the purpose of the prediction of residual life is achieved.In order to verify the accuracy of the residual life prediction method further.Accelerated thermal aging test at 130℃in laboratory.The furfural degradation data and the degree of polymerization of pressboard were obtained.The degradation data are combined with the above algorithms.The measured residual life of oil-paper insulation compared calculation result.The accuracy of residual life prediction of transformer oil impregnated pressboard is verified.