Research on infrared identification method for backside temperature rise of broken strand defects in ACSR

Aluminum conductor steel reinforced (ACSR) will produce broken strand defects after a period of operation, which seriously affects the safe and stable operation of transmission lines. In this paper, a two-dimensional LGJ-240/30 type ACSR broken strand defective heat transfer model is proposed to study the corresponding relationship between the number of broken strands of ACSR and the temperature rise of the defective backside and the load current. The model is simulated using COMSOL Multiphysics to obtain a fitting formula for the number of broken strands under natural convection conditions. The test platform is built under natural conditions to verify the feasibility and accuracy of the formula. The results show that, using the formula proposed in the article, the number of broken strands of ACSR can be identified more accurately under the condition that the load current and backside temperature are known, and improve the efficiency of infrared inspection.