US 12,462,973 B2
Magnetic structures for low leakage inductance and very high efficiency
Ionel Jitaru, Tucson, AZ (US); and Andrei Stefan Savu, Buchare (RO)
Assigned to Rompower Technology Holdings, LLC, Milford, DE (US)
Filed by Rompower Technology Holdings, LLC, Milford, DE (US)
Filed on Jun. 3, 2025, as Appl. No. 19/227,373.
Application 19/227,373 is a continuation in part of application No. 18/368,513, filed on Sep. 14, 2023, granted, now 12,322,541.
Application 18/368,513 is a continuation of application No. 17/845,609, filed on Jun. 21, 2022, granted, now 11,763,984, issued on Sep. 19, 2023.
Application 17/845,609 is a continuation of application No. 17/189,096, filed on Mar. 1, 2021, granted, now 11,367,565, issued on Jun. 21, 2022.
Application 17/189,096 is a continuation in part of application No. 16/368,186, filed on Mar. 28, 2019, granted, now 10,937,590, issued on Mar. 2, 2021.
Application 16/368,186 is a continuation of application No. 14/660,901, filed on Mar. 17, 2015, abandoned.
Claims priority of provisional application 63/133,076, filed on Dec. 31, 2020.
Claims priority of provisional application 61/955,640, filed on Mar. 19, 2014.
Prior Publication US 2025/0292958 A1, Sep. 18, 2025
Int. Cl. H01F 27/28 (2006.01); H01F 27/245 (2006.01); H01F 30/06 (2006.01)
CPC H01F 30/06 (2013.01) [H01F 27/245 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A power cell comprising:
a differential input and a differential output;
a frequency of operation and a period T, wherein the period T is an inverse of the frequency of operation;
a magnetic element formed by four identical magnetic flux conductive posts placed equidistant between two continuous magnetic flux conductive plates, each of the plates shaped to ensure a continuous flow of magnetic field through adjacent magnetic flux conductive posts;
a multilayer structure formed with an electrically conductive material, said multilayer structure including multiple layers forming a stack along length of the posts, and said multilayer structure configured as primary and secondary windings of a transformer;
the primary winding is embedded in the multilayer structure and wound around the magnetic flux conductive posts in such a way that a magnetic field induced in each of the magnetic flux conductive posts has a magnetic field polarity opposite to a polarity of the respective magnetic field of the magnetic flux conductive post adjacent the respective magnetic flux conductive post;
at least two layers of the multilayer structure, forming the secondary winding, referred to as secondary layers;
semiconductor devices on at least one of the secondary layers, said semiconductor devices positioned radially between the magnetic flux conductive posts;
resonant capacitors electrically connected to the secondary windings and the semiconductor devices;
on each of the secondary layers, a continuous conductive ring made of conductive material and which encircles from outside all the magnetic flux conductive posts;
copper pads placed between adjacent magnetic flux conductive posts, connected to the semiconductor devices; and
a current flowing through the semiconductor devices, the resonant capacitors, the continuous conductive ring, and the copper pads, wherein the current encircles each of the magnetic flux conductive posts, and a part of a conduction path is through the continuous conductive rings.