Energy recovery circuit for distributed power converters in solar cells

• US 9,379,641 B2
• Filed: 12/31/2012
• Issued: 06/28/2016
• Est. Priority Date: 10/25/2012
• Status: Active Grant

• Current Assignee: mPowerSolar Inc
• Original Assignee: SunEdison Microinverter Products LLC
• Inventors: Potharaju, Suryanarayana, Jayaraman, Vijay Shankar
• Primary Examiner(s): Finch, III, Fred E
• Assistant Examiner(s): ROSARIO BENITEZ, GUSTAVO A
• Application Number:
  US13/732,181
• Publication Number:
  US 20140119086A1
• Time in Patent Office: 1,275 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 3/40 Synchronising a generator for connection to a network or to another generator
• CPC Class Codes: H02M 1/0051 Diode reverse recovery losses
• CPC Class Codes: H02M 1/34 Snubber circuits
• CPC Class Codes: H02M 1/346 Passive non-dissipative snubbers
• CPC Class Codes: H02M 7/5387 in a bridge configuration
• 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: Y02E 70/30 Systems combining energy storage with energy generation of non-fossil origin

Abstract

A method of operating an inverter device configured on a back plane of a solar module, the inverter device comprising an energy recovery circuit device coupled to a rectifier circuit, the method comprising transferring a charge from a rectifier output to a storage capacitor configured in an energy recovery circuit; storing the charge at the storage capacitor for a time period associated with a reverse recovery time; and transferring the charge to an output of a DC bus structure to reduce a diode recovery loss in the rectifier circuit.

Claims

1. An inverter device configured on a back plane of a solar module, the inverter device comprising an energy recovery circuit coupled to a rectifier circuit at a first node and a second node, the energy recovery circuit comprising:

a first diode;

a second diode;

an inductor; and

a storage device coupled to a rectifier output from a rectifier circuit, the energy recovery circuit being configured to temporarily store a reverse recovery charge and transfer the reverse recovery charge to an output of a DC bus structure comprising the second node and a third node to reduce a diode recovery loss in the rectifier circuit;

wherein the inductor has a first end connected to the first node and a second end connected to the third node, the first diode is connected to the storage device at a fourth node, the first diode and the storage device are connected between the first node and the second node, and the second diode has a first end directly connected to the second end of the inductor and a second end directly connected to the fourth node.

2. The device of claim 1 wherein the storage device comprises a capacitor, and wherein the second node is a ground node.

3. The device of claim 1, wherein the first diode is configured to maintain the third node at the output voltage.

4. The device of claim 3 wherein the rectifier circuit comprises a full bridge diode circuit coupled with the energy recovery circuit.

5. The device of claim 1, wherein the second diode is configured to enable a switching current to flow to the output terminal.

6. The device of claim 1, wherein the inverter device is coupled to a group of solar cells.

7. The device of claim 6 wherein the group of solar cells is provided in the solar module.

8. The device of claim 1 wherein the storage device is a metal or ceramic filled capacitor structure having a capacitance determined by a frequency of switching on the rectifier circuit, the reverse recovery charge, and a voltage across the rectifier output.

9. A method of operating an inverter device configured on a back plane of a solar module, the inverter device comprising an energy recovery circuit coupled to a rectifier circuit at a first node and a second node, the energy recovery circuit comprising a first diode, a second diode, an inductor, and a storage device, wherein the inductor has a first end connected to the first node and a second end connected to a third node, the first diode is connected to the storage device at a fourth node, the first diode and the storage device are connected between the first node and the second node, and the second diode has a first end directly connected to the second end of the inductor and a second end directly connected to the fourth node, the method comprising:

transferring a charge from a rectifier output to the storage capacitor storing the charge at the storage capacitor for a time period associated with a reverse recovery time; and

transferring the charge to an output of a DC bus structure to reduce a diode recovery loss in the rectifier circuit, the output comprising the second node and the third node.

10. The method of claim 9, wherein the storage device comprises a capacitor, wherein the second terminal is a ground node.

11. The method of claim 9, wherein the first diode is configured to maintain the third node at an output voltage.

12. The method of claim 11 wherein the rectifier circuit comprises a full bridge diode circuit coupled with the energy recovery circuit.

13. The method of claim 12, wherein the second diode is configured to enable a switching current to flow to the output terminal.

14. The method of claim 9, wherein the energy recovery circuit is configured with the inverter device, the inverter device being coupled to a group of solar cells;

wherein the group of solar cells is provided in a solar module;

wherein the storage device is a metal or ceramic filled capacitor structure having a capacitance determined by a frequency of switching on the rectifier circuit, the reverse recovery charge, and a voltage across the rectifier output.