부산대학교 도서관

Ferrite is one of the most common magnetic materials used in high-frequency and high-power applications. Since the magnetic component is often the largest single element, it must be optimized for size and cost. This paper investigates the influence of magnetic material properties on the flux distribution and impedance of Mn-Zn ferrites. The analysis demonstrates the impact of conductivity, permeability and permittivity on the flux distribution and impedance, and highlights how critical it is to have complete and accurate material characteristics with frequency. The flux distribution predicted by the finite-element analysis is validated experimentally. A laminated ferrite core structure is proposed to optimize the flux distribution. The solid and laminar ferrite core options are implemented in a three-phase common-mode choke and compared experimentally. Lamination is shown to more than double the impedance from several hundred kHz to almost 10 MHz.