An inverse model for axial temperature in three-core cable joints and sensitivity analysis of material parameters

Real-time sensing of hot spot temperature in three-core cable joints is of significant importance for studying operation safety of cables， temperature rise， and dynamic load carrying capacity assessment. Therefore， focusing on 10 kV three-core cable joints and considering the variations in structures， materials， and on-site process for different types of joints， the paper constructs a simulation model for cable joint temperature fields and analyzes the temperature field distribution rules of the joints. Moreover， the paper establishes a unified inverse model for axial temperature of conductor based on axial heat flow. By employing single factor variation and orthogonal combination methods， the paper analyzes the impact of material parameter variations on the fitting degree and sensitivity of the axial inverse model for joint conductors. Simulation results demonstrate that the sensitivity coefficient and fitting goodness of the inverse model for axial temperature vary slightly， indicating good robustness for different structural， material， and on-site process variations.