Converter transformer is an important part of new power system The accurate calculation of transformer winding loss plays a crucial role in transformer design and optimization. The finite element simulation related to converter transformers has been relatively mature. However, due to the difficulty in modeling the structure of continuously transposed conductor, the calculation of electromagnetic loss of transformer windings relies heavily on empirical formulas. There are certain errors in the calculation of electromagnetic simulation results. This paper presents a method to model the winding structure of the continuously transposed conductor by using moving grid technology to solve this applicability problem. The electromagnetic loss simulation is carried out with the finite element method for the three-dimensional continuously transposed conductor model. The continuously transposed conductor model established by this method can be changed by means of parameterized modeling. The magnetic field simulation analysis can be carried out under different current and frequency conditions to solve the electromagnetic loss. It provides a useful reference for accurately solving the electromagnetic loss of continuously transposed conductor of converter transformer.