基于模糊聚类法的XLPE高压电缆绝缘老化状态评估

Aging State Assessment of High-voltage XLPE Insulation Cable Based on Fuzzy Clustering Method

目前已有较多针对高压电缆交联聚乙烯绝缘的试验室加速老化研究,但评价服役电缆绝缘老化状态的相关研究少。为此,对22根110 kV服役电缆的绝缘进行了机械拉伸、交流击穿、热重分析、红外光谱等与绝缘老化密切相关的多个影响因子的检测,并通过线性回归方法分析,选取断裂伸长率、击穿场强、热分解温度、羰基指数和熔融温度5个强相关的影响因子作为服役电缆绝缘老化状态评估的特征参数。基于模糊聚类法建立了绝缘老化评估模型,计算了各特征参数的聚类中心,建立了隶属度函数,得到了22根110 kV服役电缆的绝缘老化程度。

At present,there are many laboratory accelerated aging studies on XLPE insulation of high-voltage cables.However,there are few studies on the aging assessment of the insulation state of service cables.In this paper,the insulation aging assessment of 22 cables with 110 kV voltage level was studied.Several aging influencing factors of insulation were detected by tensile test,AC breakdown test,thermogravimetry test,infrared spectrum test and other experimental contents.Through linear regression analysis,five influencing factors that are strongly related to the aging state of insulation,such as elongation at break,breakdown field strength,thermal decomposition temperature,carbonyl index and melting temperature,were selected as the characteristic parameters of state assessment.Finally,based on the fuzzy clustering method,an insulation aging evaluation model was built.The cluster center of each characteristic parameter was calculated,and the membership function was established.The insulation aging degree of 22110 kV service cables was obtained.