Research on Fast Calculation Method of Temperature Rise for Direct Buried Cable Group

A method was proposed to achieve fast calculation of temperature rise for direct buried cable group. This method is based on the transition matrix and heat transfer theory. The interaction of the cable groups is discretized into a combination of multiple cables. The temperature rise of each cable core is calculated by finite element and the transfer matrix can be obtained by fitting operation. The transfer matrix characterizes the self-heating and cross-heating effects of the cables. The temperature rise of the directly buried cable group with 4 cables was calculated by FEM and transfer matrix in the verification calculation. Compared with the finite element method, the transfer matrix has faster calculation speed, which provides convenience for field engineers. In addition, the influence of environmental factors on the transfer matrix is also considered.