DC/DC converters are for adapting two different DC voltages to each other. In mobile applications, for example, a DC/DC converter can be use to connect an electric output from energy stores, such as batteries or supercapacitors, with volatile voltages used to a system with a stabilized voltage.
For an economically optimum calculation and dimensioning, select the technically practical voltage class first and then perform calculation and dimensioning near the upper limit.
The individual components in a DC link interact with each other and thus form systems that are capable of oscillation. This already starts with the purely DC conductor routing that interacts with the input capacities of the inverters.