US 12,476,034 B2
Inductive filtering device limiting heat generation
Eric Ravindranath Dubois, Chatou (FR); Hocine Kherbouchi, Chatou (FR); and Stéphane Guguen, Chatou (FR)
Assigned to THALES, Courbevoie (FR)
Filed by THALES, Courbevoie (FR)
Filed on Jul. 22, 2021, as Appl. No. 17/383,078.
Claims priority of application No. 2007872 (FR), filed on Jul. 27, 2020.
Prior Publication US 2022/0028594 A1, Jan. 27, 2022
Int. Cl. H01F 27/06 (2006.01); H01F 27/08 (2006.01); H01F 27/24 (2006.01); H01F 27/28 (2006.01)
CPC H01F 27/08 (2013.01) [H01F 27/24 (2013.01); H01F 27/2823 (2013.01); H01F 27/2885 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An inductive filtering device comprising:
a magnetic core,
at least one electrical cable wound around the magnetic core so as to form at least one turn, the electrical cable being intended to convey an electrical signal possessing at least one undesirable AC component superposed on a fundamental frequency of the electrical signal, and
an electrically conductive screen that is electrically insulated from its environment,
the screen being placed between the magnetic core and the electrical cable so as to allow, in the screen, via electromagnetic induction, a current to be generated the frequency of which is higher than the fundamental frequency, the screen being configured so as not to allow the current to flow in a direction parallel to that of the one or more turns formed by the winding of the electrical cable around the magnetic core, and
the device being intended to filter a given frequency, wherein the screen has a thickness at least equal to δ=(ρ/π·f·μ)1/2 with ρ: the resistivity, and μ: the absolute magnetic permeability of the material chosen to produce the screen.