Communication within a power inverter using transformer voltage frequency

• US 9,509,232 B2
• Filed: 01/20/2014
• Issued: 11/29/2016
• Est. Priority Date: 07/08/2010
• Status: Active Grant

• Current Assignee: Enphase Energy Incorporated
• Original Assignee: Sunpower Corporation (Totalenergies Se)
• Inventors: Chapman, Patrick L.
• Primary Examiner(s): Berhane, Adolf
• Assistant Examiner(s): NASH, GARY A
• Application Number:
  US14/159,084
• Publication Number:
  US 20140133197A1
• Time in Patent Office: 1,044 Days
• Field of Search: 363/8, 363/17, 363/21.04, 363/21.05, 363/65, 363/71, 363/78
• US Class Current: 1/1
• CPC Class Codes: H02M 1/0009 Devices or circuits for detecting current in a converter
• CPC Class Codes: H02M 1/08 Circuits specially adapted for the generation of control voltages for semiconductor devices incorporated in static converters
• CPC Class Codes: H02M 1/14 Arrangements for reducing ripples from dc input or output
• 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 5/458 using semiconductor devices only
• CPC Class Codes: H02M 7/53871 with automatic control of output voltage or current

Abstract

Communicating by a power inverter is provided. Processes can include outputting a first voltage at a frequency as determined by primary side control, applying the first voltage to a primary winding, generating a second voltage at a second frequency across a secondary winding, and determining the second frequency using a secondary side control, where the second frequency can provide information about an operating condition within the power inverter.

Claims

1. A method for communicating information over a power inverter, the method comprising:

providing a power supply voltage or a power supply current to a primary side controller;

determining a first frequency for a first voltage using a frequency determination module in the primary side controller, wherein in order to determine the first frequency the frequency determination module retrieves encoding data to indicate the first frequency based on the power supply voltage or power supply current;

outputting the first voltage having the first frequency determined by the primary side controller;

applying the first voltage having the first frequency to a primary winding;

generating a second voltage having a second frequency across a secondary winding; and

determining the second frequency of the second voltage using a secondary side controller, wherein the second frequency provides information about an operating condition within the power inverter.

2. The method of claim 1, further comprising determining the operating condition of a power supply corresponding to the first voltage.

3. The method of claim 1, further comprising initializing the primary side controller and the secondary side controller to set a read period and an update period to determine the operating condition.

4. The method of claim 1, further comprising controlling an input bridge to output the first voltage.

5. The method of claim 1, further comprising varying the first frequency to convey the information about the operating condition.

6. The method of claim 1, further comprising digitizing a signal from a power supply by the primary side controller into at least one data signal to the frequency determination module.

7. The method of claim 6, further comprising controlling the first frequency of the first voltage according to the encoding data identified by the at least one data signal.

8. The method of claim 1, wherein the first frequency and the second frequency are equal.

9. A method for conveying information across a power inverter having an isolation barrier, the method comprising:

determining a first frequency for a first voltage on a primary side of the power inverter using a frequency determination module wherein in order to determine the first frequency the frequency determination module retrieves encoding data to indicate the first frequency based on a power supply voltage or a power supply current, wherein the first frequency relates to an operating condition of a power source;

applying the first voltage to a primary side winding of a transformer;

generating a second voltage in a secondary side winding of the transformer; and

determining the operating condition of the power source using a second frequency of the second voltage.

10. The method of claim 9, wherein the determining the first frequency for a first voltage includes using the frequency determination module in a primary side controller.

11. The method of claim 10, wherein using the primary side controller includes determining the first frequency using the encoding data retrieved from a look-up table or an equation, and further wherein the operating condition is an input to the look-up table or the equation.

12. The method of claim 9, wherein using the primary side controller includes using an input bridge to control the first voltage.

13. The method of claim 12, further comprising sending at least one control signal from the primary side controller to at least one switch in the input bridge to generate the first voltage.

14. The method of claim 9, wherein the determining the operating condition includes using a secondary side controller to determine the second frequency.

15. The method of claim 9, wherein the first frequency and the second frequency are equal.

16. A method for conveying information through a power converter having a power supply and a load, the method comprising:

determining a first frequency related to the power supply using a primary side controller having a frequency determination module wherein in order to determine the first frequency the frequency determination module retrieves encoding data to indicate the first frequency based on a power supply voltage or a power supply current sensed at the primary side controller;

generating a first voltage having the first frequency using the primary side controller;

generating a second voltage using a transformer and the first voltage;

determining a second frequency of the second voltage using a secondary side controller.

17. The method of claim 16, wherein the determining the second frequency of the second voltage includes determining over a time period.

18. The method of claim 16, further comprising determining a change within the power supply.

19. The method of claim 18, further comprising adjusting the first frequency according to the change.

20. The method of claim 16, further comprising controlling an output voltage over the load using the second frequency determined by the secondary side controller.

21. The method of claim 16, wherein the power supply and the load are not connected.

22. The method of claim 16, wherein the first frequency and the second frequency are equal.