This paper deals with the modeling of multi-windings transformers. Based on a real example, a modeling methodology is presented. This methodology is the original part of the paper. Application examples of multi-windings phase shifting transformers (18 and 24 pulse) are presented. The whole system behavior has been simulated using the SIMSEN simulation software. Harmonics analysis of simulation results (elimination of low order harmonics 5, 7, 11, 13) has validated the proposed methodology.