岸电电缆绝缘气隙热源等效模型及载流量的影响研究

Study on the Influence of Insulation Air Gap Defects on the Current Carrying Capacity of Shore Power Cable

摘要: 岸电电缆的特殊使用工况容易导致电缆绝缘产生裂纹气隙而引起气隙放电，持续的气隙放电会导致局部温升，进而影响岸电电缆载流量。本文采用多物理场耦合分析方法，建立基于椭球体热源等效的岸电电缆气隙缺陷模型，研究不同气隙放电功率对岸电电缆温度分布的影响，并计算不同气隙放电功率下岸电电缆的载流量。结果表明：电缆温度分布与负荷电流呈二次函数关系，与气隙放电功率呈线性关系；缺陷相温度较非缺陷相温度高，但温度变化率相同；随着气隙放电功率增加，缺陷相载流量迅速下降，而非缺陷相载流量下降先缓后急。该论文的研究成果可为岸电电缆缺陷检测以及负荷电流的控制提供参考。

Abstract: The special use condition of the shore power cable is likely to cause cracking air gap in cable insulation then cause air gap discharge. Continuous air gap discharge will cause local temperature to rise, which will affect the current carrying capacity of shore power cable. In this paper, the multi-physics coupling analysis method is used to establish the air gap defect model of shore power cable. The influence of different air gap discharge power on the temperature distribution of the shore power cable is studied, and the current carrying capacity of the shore power cable under different air gap discharge power is calculated. The results show that the temperature distribution of the cable is quadratic with the load current and linear with the air gap power. With the increase of air gap discharge power, the defect phase ampacity decreases rapidly, while the non-defect phase ampacity decreases slowly and then sharply. As the air gap discharge power increases, the rated current of the defect phase decreases rapidly, the non-defect phase drops slowly and then drops rapidly. The research results of this paper can provide reference for the defect detection of shore power cable and the control of load current.