A magnetic integrated bidirectional DC-DC conversion circuit of high-frequency isolated UPS

Abstract

The utility model discloses a high frequency isolation type UPS's magnetic integrated bidirectional DC-DC conversion circuit belongs to power supply technical field, the output end of the resonant isolation circuit is used for connecting load, the magnetic element of bidirectional buck -boost circuit is formed through magnetic integration to form the staggered magnetic integrated structure. The utility model can promote power density, reduce switching loss to make the compact UPS structure.

Claims

1. A magnetically integrated bidirectional DC-DC converter circuit for a high-frequency isolated UPS, characterized in that, include: A bidirectional Buck-Boost circuit and a resonant isolation circuit are provided. The bidirectional Buck-Boost circuit is connected to the resonant isolation circuit. The output terminal of the resonant isolation circuit is used to connect to the load. The magnetic elements of the bidirectional Buck-Boost circuit are magnetically integrated to form an interleaved magnetic integration structure.

2. The magnetically integrated bidirectional DC-DC converter circuit of the high-frequency isolated UPS according to claim 1, characterized in that, The bidirectional Buck-Boost circuit includes: switching transistors Q1, Q2, Q3, and Q4; inductors L1 and L2; capacitor C1; and capacitor C2. The first terminal of capacitor C1 is electrically connected to the drain of switching transistor Q1 and the drain of switching transistor Q2, respectively. The source of switching transistor Q1 is electrically connected to the first terminal of inductor L1 and the drain of switching transistor Q4, respectively. The source of switching transistor Q2 is electrically connected to the first terminal of inductor L2 and the drain of switching transistor Q3, respectively. The two terminals of capacitor C1 are used to electrically connect to the first power supply. The second terminals of inductor L1 and inductor L2 are both electrically connected to the first terminal of capacitor C2. The source of switching transistor Q3 and the source of switching transistor Q4 are both electrically connected to the second terminal of capacitor C2. The two ends of capacitor C2 are used to electrically connect to a second power supply.

3. The magnetically integrated bidirectional DC-DC converter circuit of the high-frequency isolated UPS according to claim 2, characterized in that, The inductors L1 and L2 serve as magnetic elements of the bidirectional Buck-Boost circuit. The interleaved magnetic integrated structure includes two E-shaped magnetic cores, each of which includes a first edge magnetic post, a middle magnetic post, and a second edge magnetic post. The inductor L1 is wound around the first edge post of the first magnetic core and the first edge post and the middle post of the second magnetic core; the inductor L2 is wound around the second edge post of the second magnetic core and the second edge post and the middle post of the first magnetic core.

4. The magnetically integrated bidirectional DC-DC converter circuit of the high-frequency isolated UPS according to claim 3, characterized in that, The winding direction of inductor L1 is the same as that of inductor L2.

5. The magnetically integrated bidirectional DC-DC converter circuit of the high-frequency isolated UPS according to claim 3, characterized in that, The total number of turns of the inductor L1 on the first edge post of the first magnetic core and the first edge post of the second magnetic core is the same as the total number of turns of the inductor L2 on the second edge post of the second magnetic core and the second edge post of the first magnetic core.

6. The magnetically integrated bidirectional DC-DC converter circuit of the high-frequency isolated UPS according to claim 2, characterized in that, The resonant isolation circuit includes: isolation transformer T1, resonant inductor L3, resonant inductor L4, magnetizing inductor L5, resonant capacitor C3, resonant capacitor C4, and secondary output bridge arm. The first end of the resonant inductor L3 is electrically connected to the first end of the inductor L1 of the bidirectional Buck-Boost circuit, and the second end of the resonant inductor L3 is electrically connected to the first end of the magnetizing inductor L5 and the first end of the primary side of the isolation transformer T1, respectively. The first end of the resonant capacitor C3 is electrically connected to the first end of the inductor L2 of the bidirectional Buck-Boost circuit, and the second end of the resonant capacitor C3 is electrically connected to the second end of the magnetizing inductor L5 and the second end of the primary side of the isolation transformer T1, respectively. The first terminal of the secondary side of the isolation transformer T1 is electrically connected to the first terminal of the resonant inductor L4, and the second terminal of the secondary side of the isolation transformer T1 is electrically connected to the first terminal of the resonant capacitor C4. The second terminal of the resonant capacitor C4 and the second terminal of the resonant inductor L4 are electrically connected to the secondary output bridge arm.

7. The magnetically integrated bidirectional DC-DC converter circuit of the high-frequency isolated UPS according to claim 6, characterized in that, The secondary output bridge arm includes: diode D1, diode D2, diode D3, diode D4, and capacitor C5; The second terminal of the resonant inductor L4 is electrically connected to the positive terminal of diode D1 and the negative terminal of diode D4, respectively. The second terminal of the resonant capacitor C4 is electrically connected to the positive terminal of diode D2 and the negative terminal of diode D3, respectively. The first terminal of capacitor C5 is electrically connected to the negative terminals of diodes D1 and D2, respectively, and the second terminal of capacitor C5 is electrically connected to the positive terminals of diodes D3 and D2, respectively.

8. The magnetically integrated bidirectional DC-DC converter circuit of the high-frequency isolated UPS according to claim 6, characterized in that, The secondary output bridge arm includes: switch Q5, switch Q6, switch Q7 and switch Q8; The second terminal of the resonant inductor L4 is electrically connected to the source of the switch Q5 and the drain of the switch Q8, respectively. The second terminal of the resonant capacitor C4 is electrically connected to the source of the switch Q6 and the drain of the switch Q7, respectively.

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