Resonant converter

Abstract

To provide a resonance converter in which power can be increased or high integration can be achieved.SOLUTION: A resonance converter includes m lower conversion circuits 101-m constituting an LLC resonance converter that operates with a resonance inductor Lr in response to on-off operation of an upper switch element QH and a lower switch element QL. The resonance converter includes n upper conversion circuits 10m+1-m+n constituting an LLC resonance converter in which a primary winding T1 and a resonance capacitor Cr operate with the resonance inductor Lr in response to on-off operation of the upper switch element QH and the lower switch element QL. The resonance converter includes a control inductor Lpd (lower control inductor) that is connected in parallel with the primary winding T1 of the m lower conversion circuits 101-m, and a control inductor Lpu (upper control inductor) that is connected in parallel with the primary winding T1 of the n lower conversion circuits 101-m.SELECTED DRAWING: Figure 1

Claims

1. An upper switch element and a lower switch element are connected in series between the positive and negative terminals of a DC power supply, A resonant inductor, with one end connected to the connection point between the upper and lower switching elements, A transformer having a primary winding and a secondary winding, a resonant capacitor connected in series with the primary winding, and a rectifier connected to both ends of the secondary winding, wherein the primary winding and the resonant capacitor are connected between the other end of the resonant inductor and the negative terminal of the DC power supply, and together with the resonant inductor, m (m is an integer greater than or equal to 0) lower conversion circuits constitute an LLC resonant converter that operates by the on / off operation of the upper and lower switching elements, A transformer, a resonant capacitor, a rectifier, and n upper conversion circuits (where n is an integer greater than or equal to 0, and at least one of m and n is 2 or greater) that constitute an LLC resonant converter, the primary winding and the resonant capacitor being connected between the other end of the resonant inductor and the positive terminal of the DC power supply, and which together with the resonant inductor operate by the on / off operation of the upper and lower switching elements, m of the aforementioned lower conversion circuits have lower adjustment inductors connected in parallel with the primary windings, A resonant converter comprising an upper adjustment inductor connected in parallel with the primary windings of n upper conversion circuits.

2. The resonant converter according to claim 1, wherein the lower adjustment inductor and the upper adjustment inductor are coupled inductors.

3. The resonant converter according to claim 1 or 2, wherein the excitation inductance of the transformer in the lower conversion circuit and the upper conversion circuit is set to be greater than the inductance of the lower adjustment inductor and the upper adjustment inductor.

4. The resonant converter according to claim 3, wherein the excitation inductance of the transformer in the lower conversion circuit and the upper conversion circuit is set to be 10 times or more the inductance of the lower adjustment inductor and the upper adjustment inductor.

5. The resonant converter according to claim 1 or 2, wherein the outputs of m of the lower conversion circuits and the outputs of n of the upper conversion circuits are connected in parallel.

6. The resonant converter according to claim 1 or 2, wherein the outputs of m of the lower conversion circuits and the outputs of n of the upper conversion circuits are connected in series.

7. The resonant converter according to claim 1 or 2, wherein the outputs of m of the downward conversion circuits and the outputs of n of the upward conversion circuits are distributed into multiple sets as a multi-output converter.

8. An intermediate external terminal connected to the connection point between the other end of the resonant inductor and one end of the primary winding of the upper and lower conversion circuits, A lower external terminal connected to the connection point between the other end of the primary winding of the lower conversion circuit and one end of the resonant capacitor, The upper external terminal is connected to the connection point between the other end of the primary winding of the upper conversion circuit and one end of the resonant capacitor, The resonant converter according to claim 1 or 2, wherein the lower adjustment inductor is connected as an external inductor between the intermediate external terminal and the lower external terminal, and the upper adjustment inductor is connected as an external inductor between the intermediate external terminal and the upper external terminal.

9. The resonant converter according to claim 1 or 2, further comprising a current detection circuit connected between the connection point between the primary winding of the lower conversion circuit and the resonant capacitor and the connection point between the primary winding of the upper conversion circuit and the resonant capacitor, for detecting the current flowing through the resonant inductor.

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