| Abstract |
Magnetic components (inductors and transformers), when present in power electronics converters,
consist undoubtedly, along with the semiconductor switches, the main power loss contribution. This
fact emerges the necessity of having some easily applicable tools for their effective resistance accurate
calculation. The up to now widely used relative theoretical or empirical formulas have been extracted
under assumptions or experimental conditions that invalidate their results over several application
cases. Some lately released computer aided analyses, though useful, do not make it to escape from the
strictly bounded logic and assumptions on which the previous formulas were based.
In this paper a new expression for the calculation of high frequency copper losses in transformer and
inductor coils with round conductors, more general than the existent models and without any of the
traditionally imposed assumptions and limitations, is proposed and established by finite element
analysis (FEA) and measurement results. No complicated tables with coefficient numerical values are
necessary and the final formula extracted is simple and ready to use. Additional to this work, a
comparison between the results determined by the existent theoretical analyses and FEA clarifies their
discrepancy over specific ranges of the several parameters involved. |
