Method and apparatus for power conversion

• US 9,461,552 B2
• Filed: 05/28/2013
• Issued: 10/04/2016
• Est. Priority Date: 03/23/2006
• Status: Active Grant

• Current Assignee: Enphase Energy Incorporated
• Original Assignee: Enphase Energy Incorporated
• Inventors: Fornage, Martin
• Primary Examiner(s): NGUYEN, MATTHEW VAN
• Application Number:
  US13/903,457
• Publication Number:
  US 20130250624A1
• Time in Patent Office: 1,225 Days
• US Class Current: 1/1
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/44 with means for ensuring correct phase sequence
• 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 3/285 Single converters with a plurality of output stages connected in parallel parallel operation of a plurality of converters in dc distribution networks H02J1/10
• CPC Class Codes: H02M 3/33515 with digital control
• CPC Class Codes: H02M 7/48 using discharge tubes with control electrode or semiconductor devices with control electrode
• CPC Class Codes: H02M 7/4807 having a high frequency intermediate AC stage
• CPC Class Codes: H02M 7/537 using semiconductor devices only, e.g. single switched pulse inverters
• 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
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y10S 323/906 Solar cell systems

Abstract

A method and apparatus for converting a first power to a second power. In one embodiment, the apparatus comprises a power conversion circuit for receiving the first power and a controller, coupled to the power conversion circuit, for dynamically selecting between a regular mode and a quasi-resonant mode for operating the power conversion circuit to convert the first power to the second power.

Claims

1. Apparatus for converting a first power to a second power, comprising:

a power conversion circuit for receiving the first power; and

a controller, coupled to the power conversion circuit, for dynamically selecting between a regular mode and a quasi-resonant mode for operating the power conversion circuit to convert the first power to the second power, wherein the regular mode is a non-quasi-resonant mode.

2. The apparatus of claim 1, wherein the first power is a DC power and the second power is an AC power.

3. The apparatus of claim 1, wherein the first power is an AC power and the second power is a DC power.

4. The apparatus of claim 1, wherein the controller dynamically selects between the regular mode and the quasi-resonant mode based on a voltage ratio of the power conversion circuit.

5. The apparatus of claim 1, wherein the quasi-resonant mode is a quasi-resonant interleaved mode.

6. The apparatus of claim 1, further comprising an auxiliary quasi-resonant circuit, wherein the controller operates the auxiliary quasi-resonant circuit to switch a capacitance across a main switch of the power conversion circuit for operating in the quasi-resonant mode.

7. The apparatus of claim 6, wherein the auxiliary quasi-resonant circuit comprises a control switch, a diode, and a capacitor, wherein the capacitor is coupled between source terminals of the main switch and the control switch, a cathode terminal of the diode is coupled to the source terminal of the control switch, an anode terminal of the diode is coupled to a drain terminal of the control switch and to ground, and a gate terminal of the control switch is coupled to a memory for receiving a control signal to operate the control switch.

8. The apparatus of claim 1, wherein the regular mode is a flyback mode and the quasi-resonant mode is a quasi-resonant flyback mode.

9. A method for converting a first power to a second power, comprising:

receiving the first power at a power conversion circuit;

dynamically selecting, by a controller coupled to the power conversion circuit, a mode for operating the power conversion circuit, wherein the mode is a regular mode or a quasi-resonant mode, and wherein the regular mode is a non-quasi-resonant mode; and

converting, by the power conversion circuit, the first power to the second power utilizing the selected mode.

10. The method of claim 9, wherein the first power is a DC power and the second power is an AC power.

11. The method of claim 9, wherein the first power is an AC power and the second power is a DC power.

12. The method of claim 9, wherein selecting the mode is based on a voltage ratio of the power conversion circuit.

13. The method of claim 12, wherein the quasi-resonant mode is a quasi-resonant interleaved mode.

14. The method of claim 9, further comprising switching a capacitance across a main switch of the power conversion circuit when the quasi-resonant mode is selected.

15. The method of claim 9, wherein the regular mode is a flyback mode and the quasi-resonant mode is a quasi-resonant flyback mode.

16. A system for converting a first power to a second power, comprising:

a power source for providing the first power;

a power conversion circuit coupled to the power source; and

a controller, coupled to the power conversion circuit, for dynamically selecting between a regular mode and a quasi-resonant mode for operating the power conversion circuit to convert the first power to the second power, wherein the regular mode is a non-quasi-resonant mode.

17. The system of claim 16, wherein the power source is a DC power source, the first power is a DC power, and the second power is an AC power.

18. The system of claim 16, wherein the power source is an AC power source, the first power is an AC power, and the second power is a DC power.

19. The system of claim 16, wherein the controller dynamically selects between the regular mode and the quasi-resonant mode based on a voltage ratio of the power conversion circuit.

20. The system of claim 16, further comprising an auxiliary quasi-resonant circuit, wherein the controller operates the auxiliary quasi-resonant circuit to switch a capacitance across a main switch of the power conversion circuit for operating in the quasi-resonant mode.