Parallel hybrid converter apparatus and method

• US 10,554,141 B2
• Filed: 04/03/2017
• Issued: 02/04/2020
• Est. Priority Date: 11/20/2014
• Status: Active Grant

• Current Assignee: Huawei Digital Power Technologies Company Limited (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Dai, Heping, Ye, Liming, Fu, Dianbo, Chen, Daoshen
• Primary Examiner(s): Berhane, Adolf D
• Assistant Examiner(s): Demisse, Afework S
• Application Number:
  US15/477,504
• Publication Number:
  US 20170207707A1
• Time in Patent Office: 1,037 Days
• 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 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 3/01 Resonant DC/DC converters
• CPC Class Codes: H02M 3/07 using capacitors charged and discharged alternately by semiconductor devices with control electrode , e.g. charge pumps
• CPC Class Codes: H02M 3/1582 Buck-boost converters H02M3/1584 takes precedence
• CPC Class Codes: H02M 3/18 using capacitors or batteries which are alternately charged and discharged, e.g. charged in parallel and discharged in series
• 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 3/33576 having at least one active switching element at the secondary side of an isolation transformer
• CPC Class Codes: H02M 3/3372 of the parallel type
• 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

An apparatus comprises an isolated power converter coupled to an input dc power source, wherein the isolated power converter comprises a first switch network coupled to a first transformer winding and a second switch network coupled to a second transformer winding and a non-isolated power converter coupled to the second switch network of the isolated power converter, wherein a current flowing through the non-isolated power converter is a fraction of a current flowing through the isolated power converter.

Claims

1. An apparatus comprising:

an isolated power converter coupled to an input dc power source, wherein the isolated power converter comprises;

a first switch network coupled to a first transformer winding; and

a second switch network coupled to a second transformer winding, wherein the first transformer winding is electrically isolated from the second transformer winding; and

a non-isolated power converter coupled to the second switch network of the isolated power converter, wherein a current flowing through the non-isolated power converter is a fraction of a current flowing through the isolated power converter, and wherein the non-isolated power converter is coupled between the second transformer winding and a first input capacitor of the isolated power converter, and the first switch network is coupled between the first transformer winding and a second input capacitor of the isolated power converter, and wherein the first input capacitor and the second input capacitor are connected in series.

2. The apparatus of claim 1, wherein:

the non-isolated power converter is a four-switch buck-boost converter; and

the isolated power converter is an inductor-inductor-capacitor (LLC) resonant converter.

3. The apparatus of claim 1, wherein:

a first terminal of the second input capacitor is connected to a first terminal of the input dc power source;

a second terminal of the second input capacitor is connected to a first terminal of the first input capacitor; and

a second terminal of the first input capacitor is connected to a second terminal of the input dc power source, wherein a voltage potential at the first terminal of the input dc power source is greater than a voltage potential at the second terminal of the input dc power source.

4. The apparatus of claim 1, wherein:

the first transformer winding and the second transformer winding are on a primary side of a transformer and magnetically coupled to a secondary side winding.

5. The apparatus of claim 1, wherein:

the non-isolated power converter is configured to operate at a buck converter mode in response to a first input voltage and operate at a boost converter mode in response to a second input voltage, wherein the first input voltage is higher than the second input voltage.

6. The apparatus of claim 1, wherein:

a power delivered by the second switch network is a fraction of a power delivered by the first switch network.

7. A system comprising:

an isolated resonant converter comprising;

a first resonant tank coupled to a first switch network, wherein the first resonant tank comprises a first series resonant inductor and a first series resonant capacitor, and wherein the first series resonant inductor and the first series resonant capacitor are connected in series and between the first switch network and a first primary side winding; and

a second resonant tank coupled to a second switch network, wherein the second resonant tank comprises a second series resonant inductor and a second series resonant capacitor, and wherein the second series resonant inductor and the second series resonant capacitor are connected in series and between the second switch network and a second primary side winding, and wherein the first primary side winding and the second primary side winding are magnetically coupled to each other; and

a non-isolated converter connected to the second switch network, wherein;

a current flowing through the non-isolated converter is a fraction of a current flowing through the isolated resonant converter.

8. The system of claim 7, wherein the non-isolated converter is a buck-boost converter, and wherein:

the buck-boost converter is configured to operate at a buck converter mode in response to a first input voltage; and

the buck-boost converter is configured to operate at a boost converter mode in response to a second input voltage.

9. The system of claim 8, wherein:

the first input voltage is greater than the second input voltage.

10. A method comprising:

configuring a non-isolated converter of a hybrid converter to operate at a buck converter mode in response to a first input voltage, wherein the hybrid converter comprises an isolated converter and the non-isolated converter, and wherein;

the isolated converter comprises a first switch network, a first input/output capacitor connected to the first switch network, a second switch network and a second input/output capacitor coupled to the second switch network, and wherein the non-isolated converter is connected between the second switch network and the second input/output capacitor, and wherein the first input/output capacitor and the second input/output capacitor are connect in series;

a current flowing through the non-isolated converter is a fraction of a current flowing through the hybrid converter, and an input/output voltage of the non-isolated converter is a fraction of an input/output voltage of the hybrid converter; and

configuring the non-isolated converter to operate at a boost converter mode in response to a second input voltage.

11. The method of claim 10, wherein:

the isolated converter is an inductor-inductor-capacitor (LLC) resonant converter; and

the non-isolated converter is a buck-boost converter.

12. The method of claim 11, further comprising:

regulating the output voltage of the hybrid converter through configuring the buck-boost converter to operate at the buck converter mode when an input voltage of the hybrid converter is higher than a threshold and configuring the buck-boost converter to operate at the boost converter mode when the input voltage of the hybrid converter is lower than the threshold.

13. The method of claim 10, wherein:

configuring the isolated converter to operate in an unregulated mode; and

regulating the output voltage of the hybrid converter through the non-isolated converter.

14. The method of claim 10, wherein:

the first input voltage is greater than the second input voltage.