交联聚乙烯电缆绝缘老化的诊断方法

Insulation Aging Diagnosis Method of XLPE Cable

快速准确获知电缆绝缘老化程度或剩余使用寿命情况,可以帮助电力管理部门及时决策,确保电网安全稳定运行。首先,对交联聚乙烯电缆进行拉伸试验检测、击穿强度检测、红外光谱检测和介电谱检测,得到拉伸强度、击穿强度、羟基指数和介质损耗因数4个表征绝缘老化性能的参数与老化时间之间的关系,之后,使用这组关系式训练BP人工神经网络,对预测未知服役年限电缆绝缘老化时间误差为6.15%。最后,基于Dalal理论提出电缆绝缘老化剩余寿命模型,实现电缆绝缘剩余使用寿命的预测,为制定电缆更换计划提供理论依据。

Quickly and accurately knowing the aging degree of cable insulation or the remaining service life can help the power management department make timely decisions and ensure the safe and stable operation of the power grid.Firstly,tensile test,breakdown strength test,infrared spectrum test and dielectric spectrum test were carried out on the XLPE cable to obtain the relationship between the four parameters characterizing the insulation aging performance such as tensile strength,breakdown strength,hydroxyl index and dielectric loss factor and the aging time.Then,BP artificial neural network was trained using these relationships,and the error in predicting the insulation aging time of the cable with unknown service life was 6.15%.Finally,based on the DALAL theory,the remaining life model of cable insulation aging is proposed to realize the prediction of the remaining service life of cable insulation and provide a theoretical basis for the formulation of cable replacement plan.