TRANSFORMER AND LLC RESONANT CONVERTER HAVING THE SAME

• US 20200136518A1
• Filed: 12/31/2019
• Published: 04/30/2020
• Est. Priority Date: 05/26/2017
• Status: Active Grant

• Current Assignee: Solum Co., Ltd.
• Original Assignee: Solum Co., Ltd.
• Inventors: JI, Sang-keun, HAN, Sang-kyoo, PARK, Cheol-wan, RYU, Dong-kyun, CHOI, Heung-gyoon
• Granted Patent: US 10,958,182 B2
• Time in Patent Office: Days
• CPC Class Codes: H01F 27/06 Mounting, supporting or suspending transformers, reactors or choke coils not being of the signal type
• CPC Class Codes: H01F 27/306 Fastening or mounting coils or windings on core, casing or other support
• CPC Class Codes: H01F 3/12 Magnetic shunt paths
• CPC Class Codes: H01F 30/04 having two or more secondary windings, each supplying a separate load, e.g. for radio set power supplies
• CPC Class Codes: H02M 1/0032 Control circuits allowing low power mode operation, e.g. in standby mode
• CPC Class Codes: H02M 1/0058 by employing soft switching techniques, i.e. commutation of transistors when applied voltage is zero or when current flow is zero using an auxiliary actively switched resonant commutation circuit connected to an intermediate DC voltage or between two push-pull branches of an inverter bridge H02M7/4811; in resonant inverters H02M7/4815; in inverters operating from a resonant DC source H02M7/4826
• CPC Class Codes: H02M 3/01 Resonant DC/DC converters
• CPC Class Codes: H02M 3/33561 having more than one ouput with independent control
• CPC Class Codes: H02M 3/33571 Half-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 3/33573 Full-bridge at primary side of an isolation transformer
• CPC Class Codes: H02M 3/3382 in a push-pull circuit arrangement
• CPC Class Codes: Y02B 70/10 Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes
• CPC Class Codes: Y02P 80/10 Efficient use of energy, e.g. using compressed air or pressurized fluid as energy carrier

Abstract

A transformer and an LLC resonant converter are provided. The transformer includes first and second cores configured to include a pair of outer foots and a middle foot positioned between the outer foots, and to induce a magnetic field formation; first and second inductor winding parts configured to include a conductor surrounding a circumference of each of the pair of outer foots of the first core, and to be connected in series with each other; and first and second transformer winding parts configured to include a conductor surrounding a circumference of each of the pair of outer foots of the second core, wherein the pair of outer foots of the first core face the pair of outer foots of the second core, the middle foot of the first core faces the middle foot of the second core, and the first core and the second core are disposed to be spaced apart from each other.

Claims

1. An LLC resonant converter comprising:

a switching part configured to supply power according to a switching control signal;

a transformer configured to be connected in series with a resonance capacitor connected to the switching part; and

a rectifier configured to be connected to the transformer,

wherein the transformer includes;

first and second cores configured to include a pair of outer foots and a middle foot positioned between the outer foots, and to induce a magnetic field formation;

first and second inductor winding parts configured to include a conductor surrounding a circumference of each of the pair of outer foots of the first core, and to be connected in series with each other; and

first and second transformer winding parts configured to include a conductor surrounding a circumference of each of the pair of outer foots of the second core,

wherein the pair of outer foots of the first core face the pair of outer foots of the second core, the middle foot of the first core faces the middle foot of the second core, and the first core and the second core are disposed to be spaced apart from each other, and

wherein a first distance between one of the pair of outer foots of the first core and one of the pair of outer foots of the second core is different from a second distance between the middle foot of the first core and the middle foot of the second core.

2. The LLC resonant converter as claimed in claim 1, wherein when a current is applied to the first and second inductor winding parts, the first and second inductor winding parts generate a middle foot inductance by magnetic fluxes formed in the middle foots of the first and second cores, and generate first and second outer foot inductances by magnetic fluxes formed in the outer foots of the first and second cores.

3. The LLC resonant converter as claimed in claim 2, wherein a number of turns of the first inductor winding part and a number of turns of the second inductor winding part are equal to each other.

4. The LLC resonant converter as claimed in claim 2, wherein when a voltage is applied to the first and second inductor winding parts and the second outer foot inductance and the middle foot inductance operate resonance inductors, the first outer foot inductance operates a magnetized inductor, and

when the voltage is not applied to the first and second inductor winding parts and the first outer foot inductance and the middle foot inductance operate the resonance inductors, the second outer foot inductance operates the magnetized inductor.

5. The LLC resonant converter as claimed in claim 1, wherein the switching part is configured in a half-bridge or a full-bridge.

6. The LLC resonant converter as claimed in claim 1, wherein the first distance is smaller than the second distance.

7. The LLC resonant converter as claimed in claim 1, wherein sectional areas of the pair of outer foots of the first core are smaller than a sectional area of the middle foot of the first core.

8. The LLC resonant converter as claimed in claim 1, wherein sectional areas of the pair of outer foots of the second core are smaller than a sectional area of the middle foot of the second core.