Method for estimating power of a power converter

• US 9,300,206 B2
• Filed: 11/15/2013
• Issued: 03/29/2016
• Est. Priority Date: 11/15/2013
• Status: Active Grant

• Current Assignee: Power Systems Technologies Company Limited (Flex, Ltd.)
• Original Assignee: Power Systems Technologies Company Limited (Flex, Ltd.)
• Inventors: Ye, Zhen Z., Dunn, Jamie L.
• Primary Examiner(s): Dole, Timothy J
• Assistant Examiner(s): AHMED, YUSEF A
• Application Number:
  US14/080,992
• Publication Number:
  US 20150138857A1
• Time in Patent Office: 865 Days
• US Class Current: 1/1
• CPC Class Codes: G01R 21/06 by measuring current and voltage G01R21/08 - G01R21/133 take precedence
• CPC Class Codes: G01R 31/40 Testing power supplies testing photovoltaic devices H02S50/10
• CPC Class Codes: H02M 1/4225 using a non-isolated boost converter
• CPC Class Codes: H02M 3/157 with digital control
• 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

A controller for estimating a power of a power converter and method of estimating the same has been introduced herein. In one embodiment, the controller includes an analog/digital converter configured to provide samples of a rectified voltage waveform corresponding to a rectified sensed voltage of the power converter. The controller also includes a processor configured to estimate a minimum value of the rectified voltage waveform in accordance with the samples and remove an offset from the rectified voltage waveform to obtain an unbiased rectified voltage waveform in accordance with the estimate of the minimum value. The controller is also configured to obtain an unbiased rectified current waveform corresponding to sensed current of the power converter and provide an average power of the power converter.

Claims

1. A controller, comprising:

an analog/digital converter configured to provide samples of a first rectified voltage waveform and a second rectified voltage waveform; and

a processor configured to;

estimate a first minimum value of said first rectified voltage waveform and a second minimum value of said second rectified voltage waveform in accordance with said samples;

remove a first offset from said first rectified voltage waveform and a second offset from said second rectified voltage waveform to obtain a first unbiased rectified voltage waveform in accordance with said estimate of said first minimum value and a second unbiased rectified voltage waveform in accordance with said estimate of said second minimum value;

apply a scaling factor to said second unbiased rectified voltage waveform to determine an unbiased rectified current waveform;

multiply said first unbiased rectified voltage waveform and said unbiased rectified current waveform to determine an instantaneous power; and

provide an average of said instantaneous power to determine an average power.

2. The controller as recited in claim 1 wherein said processor is configured to estimate said first minimum value of said first rectified voltage waveform by employing a linear interpolation of said samples.

3. The controller as recited in claim 1, wherein

said processor is configured to perform a minimum value searching process to estimate said first minimum value of said first rectified voltage waveform.

4. The controller as recited in claim 1 further comprising a filter configured to substantially eliminate high-frequency noise from said first rectified voltage waveform.

5. The controller as recited in claim 1 wherein said processor is configured to determine a first unbiased reconstructed voltage waveform from said first rectified voltage waveform employing said estimate of said first minimum value and determine said first unbiased rectified voltage waveform by reversing a sign of negative samples of said first unbiased reconstructed voltage waveform.

6. The controller as recited in claim 1 wherein said processor is configured to restructure said first rectified voltage waveform into a first reconstructed voltage waveform.

7. The controller as recited in claim 6 wherein said processor is configured to determine a first unbiased reconstructed voltage waveform from said first reconstructed voltage waveform employing a high pass filter and determine said first unbiased rectified voltage waveform by reversing a sign of negative samples of said first unbiased reconstructed voltage waveform.

8. A method, comprising:

providing samples of a first rectified voltage waveform and a second rectified voltage waveform;

estimating a first minimum value of said first rectified voltage waveform and a second minimum value of said second rectified voltage waveform in accordance with said samples;

removing a first offset from said first rectified voltage waveform and a second offset from said second rectified voltage waveform to obtain a first unbiased rectified voltage waveform in accordance with said estimate of said first minimum value and a second unbiased rectified voltage waveform in accordance with said estimate of said second minimum value;

applying a scaling factor to said second unbiased rectified voltage waveform to determine an unbiased rectified current waveform;

multiplying said first unbiased rectified voltage waveform and said unbiased rectified current waveform to determine an instantaneous power; and

providing an average of said instantaneous power to determine an average power.

9. The method as recited in claim 8 further comprising employing a linear interpolation of said samples to estimate said first minimum value of said first rectified voltage waveform.

10. The method as recited in claim 8, further comprising performing a minimum value searching process to estimate said first minimum value of said first rectified voltage waveform.

11. The method as recited in claim 8, further comprising

substantially eliminating high-frequency noise from said first rectified voltage waveform.

12. The method as recited in claim 8 further comprising determining a first unbiased reconstructed voltage waveform from said first rectified voltage waveform employing said estimate of said first minimum value and reversing a sign of negative samples of said first unbiased reconstructed voltage waveform to determine said first unbiased rectified voltage waveform.

13. The method as recited in claim 8 further comprising restructuring said first rectified voltage waveform into a first reconstructed voltage waveform.

14. The method as recited in claim 13 further comprising determining a first unbiased reconstructed voltage waveform from said first reconstructed voltage waveform employing a high pass filter and reversing a sign of negative samples of said first unbiased reconstructed voltage waveform to determine said first unbiased rectified voltage waveform.

15. A power converter, comprising:

a power train including power conversion circuitry configured to receive a rectified sensed voltage corresponding to an input voltage of said power converter and a rectified current sense voltage corresponding to an input current of said power converter;

a controller, comprising;

an analog/digital converter configured to provide samples of a first rectified voltage waveform corresponding to said rectified sensed voltage and a second rectified voltage waveform corresponding to said rectified current sense voltage; and

a processor configured to

estimate a first minimum value of said first rectified voltage waveform and a second minimum value of said second rectified voltage waveform in accordance with said samples;

remove a first offset from said first rectified voltage waveform and a second offset from said second rectified voltage waveform to obtain a first unbiased rectified voltage waveform in accordance with said estimate of said first minimum value and a second unbiased rectified voltage waveform in accordance with said estimate of said second minimum value;

apply a scaling factor to said second unbiased rectified voltage waveform to determine an unbiased rectified current waveform;

multiply said first unbiased rectified voltage waveform and said unbiased rectified current waveform to determine an instantaneous power; and

provide an average of said instantaneous power to determine an average input power of said power converter.

16. The power converter as recited in claim 15 wherein said processor of said controller is configured to estimate said first minimum value of said first rectified voltage waveform by employing a linear interpolation of said samples.

17. The power converter as recited in claim 15, wherein

said processor of said controller is configured to perform a minimum value searching process to estimate said first minimum value of said first rectified voltage waveform.

18. The power converter as recited in claim 15 wherein said controller further comprises a filter configured to substantially eliminate high-frequency noise from said first rectified voltage waveform.

19. The power converter as recited in claim 15 wherein said processor of said controller is configured to determine a first unbiased reconstructed voltage waveform from said first rectified voltage waveform employing said estimate of said first minimum value and determine said first unbiased rectified voltage waveform by reversing a sign of negative samples of said first unbiased reconstructed voltage waveform.

20. The power converter as recited in claim 15 wherein said processor of said controller is configured to restructure said first rectified voltage waveform into a first reconstructed voltage waveform, determine a first unbiased reconstructed voltage waveform from said first reconstructed voltage waveform employing a high pass filter and determine said first unbiased rectified voltage waveform by reversing a sign of negative samples of said first unbiased reconstructed voltage waveform.