MAGNETIC INTEGRATED CIRCUIT FOR MULTIPHASE INTERLEAVED FLYBACK CONVERTER AND CONTROLLING METHOD THEREOF

• US 20090046486A1
• Filed: 04/07/2008
• Published: 02/19/2009
• Est. Priority Date: 08/16/2007
• Status: Active Grant

• Current Assignee: Delta Electronics Incorporated
• Original Assignee: Delta Electronics Incorporated
• Inventors: Chen, Wei, Peng, Ming Hsien, Lu, Zengyi
• Granted Patent: US 7,983,063 B2
• Time in Patent Office: Days
• US Class Current: 363/45
• CPC Class Codes: H01F 27/385 for reducing harmonics
• CPC Class Codes: H02M 3/285 Single converters with a plurality of output stages connected in parallel parallel operation of a plurality of converters in dc distribution networks H02J1/10

Abstract

The configurations of an interleaved flyback converter and a controlling method thereof are provided. The proposed two-phase interleaved flyback converter includes a transformer including a first primary winding having a first terminal, a first secondary winding having a first terminal, a second primary winding having a second terminal, a second secondary winding having a second terminal and a magnetic coupled core device, wherein the first primary, the first secondary, the second primary and the second secondary windings are wound therein, and the first terminal of the first primary winding has a polarity the same as that of any of the first terminal of the first secondary winding, the second terminal of the second primary winding and the second terminal of the second secondary winding so as to eliminate a ripple of a channel current of the converter.

Claims

1. A two-phase interleaved flyback converter, comprising:

a transformer comprising;

a first primary winding having a first terminal selectively connect to a DC power source;

a first secondary winding having a first terminal connect to an output capacitor via a first power switch;

a second primary winding having a second terminal selectively connect to the DC power source;

a second secondary winding having a second terminal connect to the output capacitor via a second power switch; and

a magnetic coupled core device, wherein the first primary, the first secondary, the second primary and the second secondary windings are wound therein, and the first terminal of the first primary winding has a polarity the same to any of the first terminal of the first secondary winding, the first terminal of the second primary winding and the second terminal of the second secondary winding so as to eliminate a ripple of a channel current of the converter.

2. A converter according to claim 1 further comprising an output capacitor having a first and a second terminals, wherein the first primary winding further comprises a second terminal, the first secondary winding further comprises a second terminal, the second primary winding further comprises a first terminal, the second secondary winding further comprises a first terminal, the first terminal of the output capacitor is grounded, and the second terminal of the output capacitor is coupled to the second terminals of the first and the second secondary windings.

3. A converter according to claim 2, wherein the first terminals of the first and the second primary windings receive a DC input voltage, and the output capacitor outputs an output voltage.

4. A converter according to claim 2 further comprising a first main circuit of a first flyback converter and a second main circuit of a second flyback converter, wherein the first main circuit comprises the first primary winding, the first secondary winding, a first switch having a first and a second terminals and a first diode having an anode and a cathode, the second main circuit comprises the second primary winding, the second secondary winding, a second switch having a first and a second terminals and a second diode having an anode and a cathode, the second terminal of the first primary winding is coupled to the first terminal of the first switch, the second terminal of the first switch is grounded, the first terminal of the second primary winding is coupled to the first terminal of the first primary winding, the second terminal of the second primary winding is coupled to the first terminal of the second switch, the second terminal of the second switch is grounded, the first terminal of the first secondary winding is coupled to the cathode of the first diode, the anode of the first diode is coupled to the first terminal of the output capacitor, the second terminal of the first secondary winding is coupled to the second terminal of the output capacitor, the first terminal of the second secondary winding is coupled to the cathode of the second diode, the anode of the second diode is coupled to the first terminal of the output capacitor, and the second terminal of the second secondary winding is coupled to the second terminal of the output capacitor.

5. A converter according to claim 4, wherein the first switch has a first control signal and the second switch has a second control signal, and a phase-shift angle between the first and second control signals is 180 degrees.

6. A converter according to claim 1, wherein the core device comprises a magnetic core having a first and a second core legs, the first core leg is mounted with the first primary and the first secondary windings, the first core leg has a first air gap, the second core leg has a second air gap, and the second core leg is mounted with the second primary and the second secondary windings.

7. A converter according to claim 1, wherein the core device comprises a magnetic core having a first to a third core legs, the first core leg is mounted with the first primary and the first secondary windings, the first core leg has the first air gap, the second core leg has the second air gap, the third core leg has the third air gap, and the third core leg is mounted with the second primary and the second secondary windings.

8. A converter according to claim 1, wherein the core device comprises a magnetic core having a first to a fourth core legs, the second core leg is mounted with the first primary and the first secondary windings, the third core leg is mounted with the second primary and the second secondary windings, and the first core leg has a first air gap and the fourth core leg has a second air gap for storing energies transmitted by the transformer.

9. A converter according to claim 1, wherein the core device comprises two magnetic cores, each of the magnetic cores has a first and a second core legs, the second core leg of the first magnetic core and the first core leg of the second magnetic core are mounted with the first primary and the first secondary windings, the second core leg of the second magnetic core is mounted with the second primary and the second secondary windings.

10. A converter according to claim 1, wherein the core device comprises a first to a third magnetic cores, each of the magnetic cores has a first and a second core legs, the second core leg of the first magnetic core and the first core leg of the second magnetic core are mounted with the first primary and the first secondary windings, the second core leg of the second magnetic core and the first core leg of the third magnetic core are mounted with the second primary and the second secondary windings, the second core leg of the first magnetic core has a first air gap, and the first core leg of the third magnetic core has a second air gap.

11. A controlling method for a multiphase interleaved flyback converter, comprising the steps of:

providing the converter with a transformer having a plurality of primary windings, each of which has a first terminal selectively connect to a DC power source and a second terminal, a plurality of secondary windings, each of which has a first terminal connect to an output capacitor via a power switch and a second terminal, and a plurality of main circuits of flyback converters, each of which has the primary and the secondary windings; and

making the first terminal of the primary winding of a first one of the flyback converters has a polarity the same as that of any of the first terminal of the secondary winding of the first one of the flyback converters and all the second terminals of the primary and the secondary windings of the remaining flyback converters so as to eliminate a ripple of a channel current of the transformer.

12. A method according to claim 11, wherein each the main circuit further comprises a switch and at least one magnetic core having at least two core legs.

13. A method according to claim 11, wherein the converter is the two-phase interleaved flyback converter as claimed in claim 2.

14. A two-phase interleaved flyback converter, comprising:

a first flyback converter having a first primary and a first secondary windings; and

a second flyback converter having a second primary and a second secondary windings, wherein the secondary winding of the second flyback converter generates an output current when a current on the primary winding of the first flyback converter is relatively increased.

15. A converter according to claim 14 further comprising a magnetic core having a first and a second core legs, wherein the first primary and the first secondary windings are wound on the first core leg and the second primary and the second secondary windings are wound on the second core leg.

16. A converter according to claim 14, wherein each of the first and the second flyback converters further comprises:

a power switch coupled between an external DC power source and the respective primary winding thereof;

a rectifier output circuit; and

an output capacitor coupled between the respective secondary winding thereof and the rectifier output circuit.