A new approach to the optimization of frequency conversion is presented according to which: 1) at first the desired ideal process is treated theoretically, 2) after that the possibility to approximate this ideal process with the actually feasible process of conversion is analyzed and, as a result of this analysis, a computer program for the control of this process is developed, 3) frequency conversion is checked in an experimental way. In contrast to the common approach to research when, at first, the converter power circuit is chosen as the basis and then the possibility of its improvement is analyzed, the modeling approach proposed by us, which is new from the methodological point of view, opens a wider sight in order to discover new useful fields for the work of the process and, consequently, makes it possible to create new conversion methods and circuits for the optimization of frequency conversion. The modeling approach discussed can be used in education and training of engineers. It includes also electromagnetic compatibility and power quality solutions realized by control methods in the version of computer programs.