Medium frequency (MF) coil with magnetic core for electronic power devices

摘要

In addition to the magnetic core (1) the coil has electrically insulating foils between conductive layers (9) on a coil former (7). Each insulating foil (10-12) is of screen type, comprising a permeability number met = 15 to 30, and a permittivity number epsilon > 1 to 20 in the frequency range of 1KHz to 1 MHz. When the magnetic core has at least one air gap (3, 4), an extra screen foil (11, 12) is allocated to adjacent boundaries of the winding (8). Pref. the screen foil thickness is 0.1 to 0.3 mm.