CN-122025345-A - Polygonal four-center column integrated matrix planar transformer

CN122025345ACN 122025345 ACN122025345 ACN 122025345ACN-122025345-A

Abstract

When primary side current flows into the second inner layer winding, magnetic flux with specific polarity is generated in the four circular middle columns, the magnetic columns are divided into two groups and phase or physical angle rotation compensation is implemented, so that magnetic fields originally dispersed in the independent transformer are subjected to 'staggered offset' in the shared polygonal magnetic core base and the top cover, the high-voltage primary side is wrapped in the middle layer, and the secondary side bearing large current is distributed on the surface layer with the best heat dissipation condition.

Inventors

LIU SUFAN
ZHOU DEHONG
JIA SHAN
LIU XIN
Xie Binxuan
ZOU JIANXIAO

Assignees

电子科技大学

Dates

Publication Date: 20260512
Application Date: 20260320

Claims (3)

1. A polygonal four-center column integrated matrix planar transformer is characterized by comprising an integrated magnetic core structure and a printed circuit board winding; The integrated magnetic core structure comprises a magnetic core assembly base and a magnetic core assembly top cover, wherein the magnetic core assembly base comprises four magnetic stand columns with circular cross sections and a polygonal bottom plate, and the magnetic stand columns are completely consistent in size and are arranged perpendicular to the polygonal bottom plate; The printed circuit board winding adopts a 6-layer plate structure, wherein each layer is sequentially configured from top to bottom, a top layer and a bottom layer are used as bus layers of a secondary side winding, a first inner layer and a fourth inner layer are used as secondary side winding layers, a second inner layer and a third inner layer are used as primary side winding layers, the primary side winding layers are physically clamped between the secondary side winding layers in a vertical space to form a completely staggered arrangement structure of primary and secondary sides, via hole arrays are arranged between the top layer and the first inner layer, between the second inner layer and the third inner layer and between the bottom layer and the fourth inner layer, and are symmetrically distributed to balance the current density of each parallel branch, and the via hole arrays of each layer are positioned in inner areas of four magnetic columns adjacent to the geometric center of the printed circuit board; on the planar layout of each winding layer, the windings encircle four magnetic columns with circular cross sections; The primary side winding is formed by adopting four-column coils to be connected in series and symmetrically distributed in an inner layer plane, wherein a second inner layer is formed by connecting two magnetic column coils in the up-down direction in series, and a third inner layer is formed by connecting two magnetic column coils in the left-right direction in series, and the coils are connected in series between the second inner layer and the third layer through holes to form 1 group of coils; The secondary side winding is formed by connecting two magnetic column coils in a serial symmetrical mode in an inner layer plane, wherein a first inner layer is formed by connecting two magnetic column coils in the left-right direction in series, 2 groups of coils are formed in a single layer, the two groups of coils are connected to the top layer through holes to realize parallel connection of the two groups of coils, and 2 turns of single magnetic column coils are equivalently wound; and the printed circuit board winding is arranged between the magnetic core assembly base and the magnetic core assembly top cover and fixed through colloid, so that a complete transformer structure is formed.
2. The polygonal four-leg integrated matrix planar transformer of claim 1, wherein the integrated core structure cuts the core shape by magnetic field simulation, rejecting low contribution redundant areas with magnetic induction less than 10% of maximum magnetic induction.
3. The polygonal four-center column integrated matrix planar transformer according to claim 1, wherein the connection of the magnetic column and the polygonal bottom plate is chamfered.

Description

Polygonal four-center column integrated matrix planar transformer Technical Field The invention belongs to the technical field of power electronics, and particularly relates to a polygonal four-center column integrated matrix planar transformer for a high-frequency LLC resonant converter. Background With the development of cloud computing and big data, the energy consumption of data centers is rapidly increasing. The current power architecture of the data center usually adopts a 12V bus, but the power architecture can cause huge energy loss and multi-stage energy conversion, so that the total efficiency of the system is reduced. To reduce bus losses and conversion stages, the industry is transitioning to 48V or 800V bus architectures, which require DC/DC converters that can directly step down high voltage (e.g., 800V) to low voltage high current (50V) and be placed near the motherboard. Isolated high output current DC/DC converters are critical to future data center power architectures. High frequency LLC resonant converters are widely used because of their high efficiency and high power density characteristics. However, conventional transformer designs face significant challenges when dealing with high output currents (e.g., above 40A): (1) The manufacturing is complex, in order to disperse the large current of the secondary side, a matrix transformer structure is often adopted, but the prior art generally uses a plurality of discrete magnetic cores or expensive 12-layer PCB windings, the manufacturing process is complex, and large distributed capacitance and common mode noise exist. (2) Core loss-core loss becomes a major limiting factor as switching frequencies push up to megahertz (MHz) levels, and core flux densities are higher in existing designs. Thus, there is a need for an integrated planar matrix transformer structure that reduces termination losses, simplifies manufacturing processes (e.g., using a simple 6-layer PCB), and effectively reduces core losses. Disclosure of Invention The invention aims to overcome the defects of the prior art, and provides a polygonal four-center column integrated matrix planar transformer, which effectively reduces the magnetic core loss and the transformer volume through a unique magnetic integrated structure and a PCB winding design and realizes the high efficiency and the high power density of a high-frequency LLC resonant converter under the megahertz switching frequency. In order to achieve the aim, the polygonal four-center column integrated matrix planar transformer is characterized by comprising an integrated magnetic core structure and a printed circuit board winding; The integrated magnetic core structure comprises a magnetic core assembly base and a magnetic core assembly top cover, wherein the magnetic core assembly base comprises four magnetic stand columns with circular cross sections and a polygonal bottom plate, and the magnetic stand columns are completely consistent in size and are arranged perpendicular to the polygonal bottom plate; The printed circuit board winding adopts a 6-layer plate structure, wherein each layer is sequentially configured from top to bottom, a top layer and a bottom layer are used as bus layers of a secondary side winding, a first inner layer and a fourth inner layer are used as secondary side winding layers, a second inner layer and a third inner layer are used as primary side winding layers, the primary side winding layers are physically clamped between the secondary side winding layers in a vertical space to form a completely staggered arrangement structure of primary and secondary sides, via hole arrays are arranged between the top layer and the first inner layer, between the second inner layer and the third inner layer and between the bottom layer and the fourth inner layer, and are symmetrically distributed to balance the current density of each parallel branch, and the via hole arrays of each layer are positioned in inner areas of four magnetic columns adjacent to the geometric center of the printed circuit board; on the planar layout of each winding layer, the windings encircle four magnetic columns with circular cross sections; The primary side winding is formed by adopting four-column coils to be connected in series and symmetrically distributed in an inner layer plane, wherein a second inner layer is formed by connecting two magnetic column coils in the up-down direction in series, and a third inner layer is formed by connecting two magnetic column coils in the left-right direction in series, and the coils are connected in series between the second inner layer and the third layer through holes to form 1 group of coils; The secondary side winding is formed by connecting two magnetic column coils in a serial symmetrical mode in an inner layer plane, wherein a first inner layer is formed by connecting two magnetic column coils in the left-right direction in series, 2 groups of coils are formed in a single layer, the