夏川,刘会家,吴刚梁,夏竹青.含防爆盒的三芯电缆中间接头散热性能及载流量研究[J].电测与仪表,2022,59(9):47-52. Xiachuan,1,2,3.Research on Heat Dispersion and Ampacity of Three-Core Cable Joints with Explosion-Proof Box[J].Electrical Measurement & Instrumentation,2022,59(9):47-52.
含防爆盒的三芯电缆中间接头散热性能及载流量研究
Research on Heat Dispersion and Ampacity of Three-Core Cable Joints with Explosion-Proof Box
To avoid cable faults caused by outside destroy and prevent the failure of cable joints from spreading to other nearby cables after a fire, the explosion-proof box must be added to the newly installed cable joints according to the latest regulation. Given that the sealing of explosion-proof box will increase the heat transfer path, it will inevitably affect the heat dissipation performance of cable joints. To further study the temperature rise and ampacity characteristics of the three-core cable intermediate joint with explosion-proof box in distribution network, this paper takes the joint of 20kV three-core cable as an example, then develops the magnetic-thermal coupling model of the three-core cable joint on the basis of contact resistance. The temperature rise of the joint with explosion-proof box under 289A current is calculated, and the accuracy of simulation calculation is verified by comparing the operation data. Finally, the influence of the explosion-proof box on the current carrying capacity of the joint is analyzed. The cavity in the explosion-proof box greatly reduces the heat dissipation performance of the joint. Compared with cable body, the ampacity is reduced by about 37.1%, while the heat dissipation of the joint can be greatly enhanced by pouring the epoxy resin ab glue, The current carrying capacity is increased by nearly 41.1% compared with that without the epoxy resin ab glue. It can provide a reference for the development of operation strategy, which is helpful to the safe and stable operation of three-core cables.
