Numerical Calculation of the Cyclic Load Carrying Capacity of Direct Buried Cables considering Thermoelectric Coupling

Loads in power cable lines are often predominantly non-constant loads such as cyclic loads, and if the long-term rated current capacity to characterize the current carrying capacity of power cable lines is often too conservative, reducing the utilization of expensive power cable assets, thus analyzing the through-flow capacity of cyclically loaded power cable lines is of great practical significance. The solution time is decomposed into some series of time steps by finite difference, and the time step is determined as 10 minutes, which can satisfy the small calculation error when thermoelectric coupling. The steady-state numerical analysis method analyzes the steady-state temperature field to obtain the initial temperature field distribution of the buried cable. The entire transient temperature rise is solved time step by time step. Using an iterative approach, the load capacity can be solved for a given cyclic load waveform. The solution results are compared with the CYMCAP calculation results, and the numerical calculation results are significantly higher than the CYMCAP calculation results, which can effectively improve the current-carrying capacity and utilization of the cable.