Fast Calculation of Steady Temperature Rise for Running Three-phase Cable Group in Ducts based on Transfer Matrix

This paper presented a method based on transfer matrix and superposed thermal field to achieve fast calculation for steady state temperature rise of three-phase cable group in ducts. The heat response of cable groups was discretized into combination of self-heating and mutual heating in multi-loop cables. The heat interaction between any two pairs was described by transfer coefficient, and the heat transfer matrix was obtained to represent the thermal characteristics of cable groups. The fast calculation was realized by combining a simple iteration of “temperature-loss” based on heat transfer matrix. The extraction process of transfer matrix by FEM and the application of fast calculation method was illustrated, and the result of the fast calculation method was compared with that of FEM, which proved the feasibility, simplicity and accuracy of the fast calculation method presented in this paper.