摘要
三芯电缆中间接头是电缆系统中的薄弱部位,加装防爆盒在有效防止接头发生故障后影响其余电缆正常工作的同时也会对接头表面温度分布产生影响。建立35 kV含防爆盒电缆中间接头三维真型模型,基于有限元理论建立多物理场耦合仿真模型,研究了接触电阻对防爆盒内接头温度的影响以及灌胶防爆盒对接头载流量的影响;通过模拟绝缘老化以及发热缺陷情况,得出含防爆盒电缆中间接头表面温度分布规律。结果表明:灌胶防爆盒因热阻效应导致导体载流量较裸接头工况下降12.77%,绝缘老化对表面温升影响较小;接续管处出现发热缺陷时,灌胶防爆盒的存在会使接头表面温度极值区由传统端部集中迁移至接续管对应外表面区域,单相、两相缺陷分别使温升提高11.65、13.3℃;通过监测接续管中心外接头表面六点位置的温升幅度可以识别灌胶防爆盒内电缆接头发热缺陷。该成果为电缆中间接头的状态监测与可靠性评估提供了理论依据,对智能电网设备状态检修规程的优化具有参考价值。
The three-core cable intermediate joint is a vulnerable component of the cable system.The addition of an explosionproof box can effectively prevent joint failure from affecting the normal operation of other cables,and also affects the surface temperature distribution of the joint.In this paper,a three-dimensional full-scale model of a 35 kV cable intermediate joint with an explosion-proof box is developed,and a multiphysics coupled simulation model based on finite element theory is established.The influence of contact resistance on the temperature of the joint inside the explosion-proof box and the influence of the gel-filled explosion-proof box on the current-carrying capacity of the joint are studied.By simulating insulation aging and heating defect conditions,the surface temperature distribution characteristics of cable intermediate joints with explosionproof boxes are obtained.The results show that,due to the thermal resistance effect,the conductor current-carrying capacity of the gel-filled explosion-proof box decreases by 12.77%compared with the bare joint condition,and insulation aging has little effect on the surface temperature rise.When a heating defect occurs at the splice tube,the presence of the gel-filled explosion-proof box causes the maximum temperature region on the joint surface to shift from the traditional end region to the outer surface corresponding to the splice tube.Single-phase and two-phase defects increase the temperature rise by 11.65℃and 13.3℃,respectively.Heating defects of cable joints inside gel-filled explosion-proof boxes can be identified by monitoring the temperature rise amplitudes at six positions on the outer surface of the joint at the center of the splice tube.The results provide a theoretical basis for condition monitoring and reliability evaluation of cable intermediate joints and have reference value for optimizing condition-based maintenance procedures for smart grid equipment.
作者
张东东
万慧娟
张翼
余佶成
叶桐珲
乔新涵
焦婷
汪垠衫
王若曦
ZHANG Dongdong;WAN Huijuan;ZHANG Yi;YU Jicheng;YE Tonghui;QIAO Xinhan;JIAO Ting;WANG Yinshan;WANG Ruoxi(School of Electric Power Engineering,Nanjing Institute of Technology,Nanjing 211167,China;China Electric Power Research Institute,Wuhan 430074,China;China University of Mining and Technology,Xuzhou 221116,China;Electric Power Science Research Institute,State Grid Shanghai Electric Power Company,Shanghai 200080,China)
出处
《电力科学与技术学报》
北大核心
2026年第1期298-306,共9页
Journal of Electric Power Science And Technology
基金
湖北省自然科学基金(2023AFB074)
江苏高校“青蓝工程”(SJS202414)
中国博士后科学基金(2023M732412)。
关键词
中间接头
防爆盒
接触电阻
绝缘老化
有限元理论
intermediate joint
explosion-proof box
contact resistance
insulation aging
finite element theory
