Objectives  Because of the characteristics of submarine direct current (DC) transmission cables, traditional circuit inductance calculation methods are unable to fit the system. There is a big error between the calculating value and the actual value. This paper studies the finite element method to reduce the calculation error.

  Methods  The applicability of common line inductance calculation formulas to submarine DC system is discussed firstly. Then a short-circuit testing system is set up. The inductance of circuit in the system is measured, and a simulation model of the testing system is established. For a comparing purpose, the total inductance of the line is calculated by finite element analysis in the ANSYS/Maxwell software too. With the inductance values, the equivalent circuit model of the testing system is simulated in the Matlab/Simulink software. The simulation waveforms of the short-circuit current and the measured waveform are analyzed and compared.

  Results   The result shows that the finite element analysis method is able to improve the accuracy of calculation of submarine DC transmission line equivalent inductance, and reduce the error in DC power system transient analysis.

  Conclusions  The achievement can provide support for further simulation model development and calculation method research.