This paper proposes a reduced-order (RO) model of power electronic components based on the proper orthogonal decomposition. Starting from a full-wave finite-element model and several snapshots (solutions at different frequencies), the RO model is constructed. Local field values (e.g., magnetic flux density, electric current density, magnetic field, or electric field) and global quantities (e.g., characteristic complex impedance and Joule losses) can be determined for the intermediate frequencies with a very low computational cost and high accuracy. Particular attention is paid to the choice of the most suitable snapshots by means of three different greedy algorithms, the performance of which is compared. We adopt an automatic greedy algorithm that depends only on the RO model.