防火防爆装置对10kV三芯电缆中间接头温升及载流量的影响

为了分析不同类型防火防爆装置对10 kV三芯电缆中间接头温升及载流量的影响，搭建了大电流温升试验平台，开展了无防火防爆装置、含不锈钢、铝镁合金和玻璃钢防爆盒以及含防爆毯、防火毯共6组温升试验。试验结果表明，在散热效果方面，防爆毯最好，不锈钢防爆盒最差；不同试验组在电缆中间接头径向和轴向表现出相似的温度分布规律。为便于工程应用的同时开展机理分析，基于温升试验数据，分别从解析法和数值法出发，计算了不同试验组电缆的载流量。研究结果表明，含不锈钢防爆盒电缆载流量下降比例超过10%，含防爆毯电缆载流量下降比例仅为1%左右，其余下降比例约为10%。研究结果可为电缆中间接头防火防爆装置的选型设计提供参考。

Influence of fire-proof and explosion-proof devices on temperature rise and ampacity of 10kV three-core cable middle joint

In order to analyze the influence of different types of fire-proof and explosion-proof devices on temperature rise and ampacity of the 10 kV three-core cable middle joint, a large current temperature rise test platform was built, and six groups of temperature rise tests were carried out, including no fire-proof and explosion-proof devices, explosion-proof boxes containing stainless steel, aluminum-magnesium alloy and FRP, and explosion-proof blankets and fire blankets. The test results show that the explosion-proof blanket is the best, and the stainless steel explosion-proof box is the worst. Different test groups show similar temperature distribution in radial and axial direction of cable middle joints. In order to facilitate engineering application and carry out mechanism analysis at the same time, based on temperature rise test data, the ampacity of different test groups was calculated by analytical method and numerical method respectively. The results show that the load rate of the cable containing stainless steel explosion-proof box decreases by more than 10%, the load rate of the cable containing explosion-proof blanket decreases by only about 1%, and the rest decreases by about 10%. The research results can provide reference for the selection and design of the cable joint fireproof and explosion-proof device.