Flyback converter with capacitor module and switching module

• US 10,103,638 B1
• Filed: 08/09/2017
• Issued: 10/16/2018
• Est. Priority Date: 08/09/2017
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Leong, Kennith Kin
• Primary Examiner(s): Ahmed, Yusef A
• Application Number:
  US15/673,089
• Time in Patent Office: 433 Days
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 1/4258 using a single converter stage both for correction of AC input power factor and generation of a regulated and galvanically isolated DC output voltage H02M1/4241 takes precedence
• CPC Class Codes: H02M 3/33515 with digital control
• CPC Class Codes: H02M 3/33523 with galvanic isolation between input and output of both the power stage and the feedback loop
• CPC Class Codes: H02M 3/3353 having at least two simultaneously operating switches on the input side, e.g. "double forward" or "double (switched) flyback" converter
• CPC Class Codes: H02M 3/33561 having more than one ouput with independent control
• CPC Class Codes: H02M 3/33576 having at least one active switching element at the secondary side of an isolation transformer
• CPC Class Codes: H02M 3/33592 having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
• CPC Class Codes: H02M 3/3378 in a push-pull configuration of the parallel type H02M3/3374 takes precedence
• 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

Abstract

In an example, a circuit for voltage regulation includes a capacitor module, a multiple winding transformer, and a switching module. The capacitor module includes a first capacitor and a second capacitor. The multiple winding transformer includes a first primary side winding, a second primary side winding, and a secondary side winding. The switching module is configured to selectively switch the multiple winding transformer in a first state and a second state. During the first state, the switching module electrically couples the capacitor module to the multiple winding transformer. During the first state, the switching module electrically couples the first capacitor to the first primary side winding and electrically couples the second capacitor to the second primary side winding. During the second state, the switching module electrically couples the secondary side winding to a load. In another example, a circuit includes a voltage doubler module, transformer, and switching module.

Claims

1. A circuit for voltage regulation comprising:

a capacitor module comprising a first capacitor and a second capacitor;

a multiple winding transformer comprising a first primary side winding, a second primary side winding, and a secondary side winding;

a switching module configured to selectively switch the multiple winding transformer in a first state and a second state;

wherein, during the first state, the switching module electrically couples the capacitor module to the multiple winding transformer such that the capacitor module charges a magnetic field of the multiple winding transformer;

wherein, during the first state, the switching module electrically couples the first capacitor to the first primary side winding and electrically couples the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein, during the second state, the switching module electrically couples the secondary side winding to a load such that the magnetic field of the multiple winding transformer discharges to the secondary side winding to provide a regulated voltage to the load; and

wherein the switching module is further configured to;

select an interleaving control scheme when a voltage at a voltage source supplying power to the capacitor module exceeds a first predetermined voltage;

select a non-interleaving control scheme when the voltage at the voltage source supplying power to the capacitor module does not exceed the first predetermined voltage and a voltage output at the load exceeds a second predetermined voltage; and

select the interleaving control scheme when the voltage at the voltage source supplying power to the capacitor module does not exceed the first predetermined voltage and the voltage output at the load does not exceed the second predetermined voltage.

2. The circuit of claim 1, further comprising a rectification module configured to:

generate a first rectified current to charge the first capacitor using an alternating current flowing when the alternating current flows in a first direction; and

generate a second rectified current to charge the second capacitor using the alternating current when the alternating current flows in a second direction that is opposite to the first direction.

3. The circuit of claim 2, further comprising:

wherein the rectification module comprises a first diode configured to generate a channel for the first rectified current and to block the second rectified current; and

wherein the rectification module comprises a second diode configured to generate a channel for the second rectified current and to block the first rectified current.

4. The circuit of claim 1, wherein the capacitor module further comprises a third capacitor coupled in parallel with a series path formed by the first capacitor and the second capacitor, the circuit further comprising a rectification module configured to:

generate a first rectified current to charge the first capacitor, the second capacitor, and the third capacitor using an alternating current when the alternating current flows in a first direction; and

generate a second rectified current to charge the first capacitor, the second capacitor, and the third capacitor using the alternating current when the alternating current flows in a second direction that is opposite to the first direction.

5. The circuit of claim 1, wherein the first capacitor comprises a positive terminal and a negative terminal, wherein the second capacitor comprises a positive terminal and a negative terminal, wherein the first primary side winding comprises a first node and a second node, wherein the second primary side winding comprises a first node and a second node, wherein the second node of the first primary side winding, the first node of the second primary side winding, the negative terminal of the first capacitor, and the positive terminal of the second capacitor are coupled together, and wherein the switching module comprises:

a first diode comprising an anode and a cathode, the cathode of the first diode being coupled to the positive terminal of the first capacitor and the anode of the first diode being coupled to the second node of the second primary side winding;

a first switching element comprising a gate, drain, and source, the drain of the first switching element being coupled to the anode of the first diode and the source of the first switching element being coupled to the negative terminal of the second capacitor;

a second diode comprising an anode and a cathode, the anode of the second diode being coupled to the negative terminal of the second capacitor and the cathode of the second diode being coupled to the first node of the first primary side winding; and

a second switching element comprising a gate, drain, and source, the drain of the second switching element being coupled to the positive terminal of the first capacitor and the source of the second switching element being coupled to the cathode of the second diode.

6. A circuit for voltage regulation comprising:

a capacitor module comprising a first capacitor and a second capacitor;

a multiple winding transformer comprising a first primary side winding, a second primary side winding, and a secondary side winding;

a switching module configured to selectively switch the multiple winding transformer in a first state and a second state;

wherein, during the first state, the switching module electrically couples the capacitor module to the multiple winding transformer such that the capacitor module charges a magnetic field of the multiple winding transformer;

wherein, during the first state, the switching module electrically couples the first capacitor to the first primary side winding and electrically couples the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein, during the second state, the switching module electrically couples the secondary side winding to a load such that the magnetic field of the multiple winding transformer discharges to the secondary side winding to provide a regulated voltage to the load;

wherein the first state is a first interleaving state and the second state is a second interleaving state;

wherein, to electrically couple the capacitor module to the multiple winding transformer, the switching module is configured to electrically couple the second capacitor to the multiple winding transformer such that the second capacitor charges the magnetic field of the multiple winding transformer;

wherein, during the second interleaving state, the switching module generates a channel for recuperating leakage inductance energy from the second primary side winding to the first capacitor;

wherein the switching module is further configured to selectively switch the multiple winding transformer in a third interleaving state and a fourth interleaving state;

wherein, during the third interleaving state, the switching module electrically couples the first capacitor to the multiple winding transformer such that the first capacitor charges the magnetic field of the multiple winding transformer;

wherein, during the third interleaving state, the switching module electrically couples the first capacitor to the first primary side winding and electrically couples the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein, during the fourth interleaving state, the switching module discharges the magnetic field of the multiple winding transformer to the secondary side winding to provide the regulated voltage to the load; and

wherein, during the fourth interleaving state, the switching module generates a channel for recuperating leakage inductance energy from the first primary side winding to the second capacitor.

7. A circuit for voltage regulation comprising:

a capacitor module comprising a first capacitor and a second capacitor;

a multiple winding transformer comprising a first primary side winding, a second primary side winding, and a secondary side winding;

a switching module configured to selectively switch the multiple winding transformer in a first state and a second state;

wherein, during the first state, the switching module electrically couples the capacitor module to the multiple winding transformer such that the capacitor module charges a magnetic field of the multiple winding transformer;

wherein, during the first state, the switching module electrically couples the first capacitor to the first primary side winding and electrically couples the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein, during the second state, the switching module electrically couples the secondary side winding to a load such that the magnetic field of the multiple winding transformer discharges to the secondary side winding to provide a regulated voltage to the load;

wherein, to electrically couple the capacitor module to the multiple winding transformer, the switching module is configured to electrically couple a series combination of the first capacitor and the second capacitor to the multiple winding transformer such that the series combination of the first capacitor and the second capacitor charges the magnetic field of the multiple winding transformer; and

wherein, during the second state, the switching module generates a channel for recuperating leakage inductance energy from a series combination of the first primary side winding and the second primary side winding to the series combination of the first capacitor and the second capacitor.

8. The circuit of claim 7, wherein the switching module is further configured to operate using only a non-interleaving control scheme.

9. A method for voltage regulation comprising:

selectively switching, by a switching module, a multiple winding transformer in a first state and a second state, the multiple winding transformer comprising a first primary side winding, a second primary side winding, and a secondary side winding;

wherein selectively switching the multiple winding transformer in the first state comprises electrically coupling a capacitor module to the multiple winding transformer such that the capacitor module charges a magnetic field of the multiple winding transformer, the capacitor module comprising a first capacitor and a second capacitor;

wherein selectively switching the multiple winding transformer in the first state comprises electrically coupling the first capacitor to the first primary side winding and electrically coupling the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein selectively switching the multiple winding transformer in the second state comprises electrically coupling the secondary side winding to a load such that the magnetic field of the multiple winding transformer discharges to the secondary side winding to provide a regulated voltage to the load;

selecting, by the switching module, an interleaving control scheme when a voltage at a voltage source supplying power to the capacitor module exceeds a first predetermined voltage;

selecting, by the switching module, a non-interleaving control scheme when the voltage at the voltage source supplying power to the capacitor module does not exceed the first predetermined voltage and a voltage output at the load exceeds a second predetermined voltage; and

selecting, by the switching module, the interleaving control scheme when the voltage at the voltage source supplying power to the capacitor module does not exceed the first predetermined voltage and the voltage output at the load does not exceed the second predetermined voltage.

10. The method of claim 9, further comprising:

generating, by a rectification module, a first rectified current to charge the first capacitor using an alternating current flowing when the alternating current flows in a first direction; and

generating, by the rectification module, a second rectified current to charge the second capacitor using the alternating current when the alternating current flows in a second direction that is opposite to the first direction.

11. The method of claim 10, further comprising:

wherein the rectification module comprises a first diode configured to generate a channel for the first rectified current and to block the second rectified current; and

wherein the rectification module comprises a second diode configured to generate a channel for the second rectified current and to block the first rectified current.

12. The method of claim 9, wherein the capacitor module further comprises a third capacitor coupled in parallel with a series path formed by the first capacitor and the second capacitor, the method further comprising:

generating a first rectified current to charge the first capacitor, the second capacitor, and the third capacitor using an alternating current when the alternating current flows in a first direction; and

generating a second rectified current to charge the first capacitor, the second capacitor, and the third capacitor using the alternating current when the alternating current flows in a second direction that is opposite to the first direction.

13. The method of claim 9, wherein the first capacitor comprises a positive terminal and a negative terminal, wherein the second capacitor comprises a positive terminal and a negative terminal, wherein the first primary side winding comprises a first node and a second node, wherein the second primary side winding comprises a first node and a second node, wherein the second node of the first primary side winding, the first node of the second primary side winding, the negative terminal of the first capacitor, and the positive terminal of the second capacitor are coupled together, and wherein the switching module comprises:

a first diode comprising an anode and a cathode, the cathode of the first diode being coupled to the positive terminal of the first capacitor and the anode of the first diode being coupled to the second node of the second primary side winding;

a first switching element comprising a gate, drain, and source, the drain of the first switching element being coupled to the anode of the first diode and the source of the first switching element being coupled to the negative terminal of the second capacitor;

a second diode comprising an anode and a cathode, the anode of the second diode being coupled to the negative terminal of the second capacitor and the cathode of the second diode being coupled to the first node of the first primary side winding; and

a second switching element comprising a gate, drain, and source, the drain of the second switching element being coupled to the positive terminal of the first capacitor and the source of the second switching element being coupled to the cathode of the second diode.

14. A method for voltage regulation comprising:

selectively switching, by a switching module, a multiple winding transformer in a first state and a second state, the multiple winding transformer comprising a first primary side winding, a second primary side winding, and a secondary side winding;

wherein selectively switching the multiple winding transformer in the first state comprises electrically coupling a capacitor module to the multiple winding transformer such that the capacitor module charges a magnetic field of the multiple winding transformer, the capacitor module comprising a first capacitor and a second capacitor;

wherein selectively switching the multiple winding transformer in the first state comprises electrically coupling the first capacitor to the first primary side winding and electrically coupling the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein selectively switching the multiple winding transformer in the second state comprises electrically coupling the secondary side winding to a load such that the magnetic field of the multiple winding transformer discharges to the secondary side winding to provide a regulated voltage to the load;

wherein the first state is a first interleaving state and the second state is a second interleaving state;

wherein electrically coupling the capacitor module to the multiple winding transformer comprises electrically coupling the second capacitor to the multiple winding transformer such that the second capacitor charges the magnetic field of the multiple winding transformer;

wherein selectively switching the multiple winding transformer in the second interleaving state comprises generating a channel for recuperating leakage inductance energy from the second primary side winding to the first capacitor;

selectively switching, by the switching module, the multiple winding transformer in a third interleaving state and a fourth interleaving state;

wherein selectively switching the multiple winding transformer in the third interleaving state comprises electrically coupling the first capacitor to the multiple winding transformer such that the first capacitor charges the magnetic field of the multiple winding transformer;

wherein selectively switching the multiple winding transformer in the third interleaving state comprises electrically coupling the first capacitor to the first primary side winding and electrically coupling the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein selectively switching the multiple winding transformer in the fourth interleaving state comprises generating a channel for recuperating leakage inductance energy from the first primary side winding to the second capacitor; and

wherein selectively switching the multiple winding transformer in the fourth interleaving state comprises electrically coupling the secondary side winding to the load such that the magnetic field of the multiple winding transformer discharges to the secondary side winding to provide a regulated voltage to the load.

15. A method for voltage regulation comprising:

selectively switching, by a switching module, a multiple winding transformer in a first state and a second state, the multiple winding transformer comprising a first primary side winding, a second primary side winding, and a secondary side winding;

wherein selectively switching the multiple winding transformer in the first state comprises electrically coupling a capacitor module to the multiple winding transformer such that the capacitor module charges a magnetic field of the multiple winding transformer, the capacitor module comprising a first capacitor and a second capacitor;

wherein selectively switching the multiple winding transformer in the first state comprises electrically coupling the first capacitor to the first primary side winding and electrically coupling the second capacitor to the second primary side winding such that power flows from the first capacitor to the second capacitor when the first capacitor has a higher voltage than the second capacitor and such that power flows from the second capacitor to the first capacitor when the second capacitor has a higher voltage than the first capacitor;

wherein selectively switching the multiple winding transformer in the second state comprises electrically coupling the secondary side winding to a load such that the magnetic field of the multiple winding transformer discharges to the secondary side winding to provide a regulated voltage to the load;

wherein electrically coupling the capacitor module to the multiple winding transformer comprises electrically coupling a series combination of the first capacitor and the second capacitor to the multiple winding transformer such that the series combination of the first capacitor and the second capacitor charges the magnetic field of the multiple winding transformer; and

wherein selectively switching the multiple winding transformer in the second state comprises generating a channel for recuperating leakage inductance energy from a series combination of the first primary side winding and the second primary side winding to the series combination of the first capacitor and the second capacitor.

16. The method of claim 15, wherein the switching module is further configured to operate using only a non-interleaving control scheme.