The present invention relates to a method for obtaining switching angles (α1, . . . , αi), and to an associated conversion system. In the method, possible values (IM) are established for a modulation index, within a predetermined range of values (R) and divided into a plurality of segments (S1, . . . , Sj); a value is obtained for each of the switching angles (α1, . . . , αi) in each segment (S1, . . . , Sj) and for each of the possible values (IM); a switching curve (SC) is formed for each switching angle (α1, . . . , αi) over the entire range (R); and the height or amplitude and the slope of each switching curve (SC) at a possible value shared by two segments (S1, . . . , Sj) are considered constant.