Power extractor detecting power and voltage changes

• US 9,130,390 B2
• Filed: 07/07/2007
• Issued: 09/08/2015
• Est. Priority Date: 11/27/2006
• Status: Active Grant

• Current Assignee: Apparent Labs LLC
• Original Assignee: Xslent Energy Technologies, LLC
• Inventors: Besser, David A., Matan, Stefan
• Primary Examiner(s): Behm, Harry
• Application Number:
  US11/774,566
• Publication Number:
  US 20080191675A1
• Time in Patent Office: 2,985 Days
• Field of Search: 323/262, 323/906, 323/301, 323/222, 323/225, 323/299, 323/300, 307/78, 307/84, 320/101, 320/102
• US Class Current: 1/1
• CPC Class Codes: G05F 1/67 to the maximum power available from a generator, e.g. from solar cell
• CPC Class Codes: H02J 2300/20 The dispersed energy generation being of renewable origin
• CPC Class Codes: H02J 2300/24 of photovoltaic origin
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 3/381 Dispersed generators
• CPC Class Codes: H02J 3/46 Controlling of the sharing of output between the generators, converters, or transformers
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/35 with light sensitive cells
• CPC Class Codes: H02M 3/158 including plural semiconductor devices as final control devices for a single load
• CPC Class Codes: Y02E 10/56 Power conversion systems, e.g. maximum power point trackers
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects

Abstract

In some embodiments, a power extractor utilizes power transfer circuitry with analysis circuitry to detect a power slope and to control the magnitude of the current in response to the detected power slope. The power analysis circuitry may increase the current as long as the power slope shows an increase in power and may decrease the current as long as the power slope shows a decrease in power. The magnitude of the current is responsive to the duty cycle of the switching circuitry and to the detected power slope. Other embodiments are described and claimed.

Claims

1. An apparatus comprising:

a first node to couple to a power supply to supply power;

a second node to couple to a load to receive power; and

a power extractor including;

power transfer circuitry to transfer power having a current to the second node based on power supplied at the first node,

power change analysis circuitry to detect an instantaneous power change and a voltage change at the first node, and at least partially control the current of the power to be transferred in response to the detected instantaneous power change and voltage change at the first node, the current to the second node to

decrease when the power change and the voltage change at the first node are both increasing, and when the power change and the voltage change at the first node are both decreasing, and

increase when the power change at the first node is decreasing and the voltage change at the first node is increasing, and when the power change at the first node is increasing and the voltage change at the first node is decreasing,

switching circuitry to control the power transfer circuitry; and

switching control circuitry to control a duty cycle of the switching circuitry, wherein the power change analysis circuitry operates in different modes and wherein in an ordinary operating mode, under some conditions, the power analysis circuitry causes the power transfer circuitry to

increase the current of the power to be transferred by decreasing the duty cycle of the switching control circuitry, and

decrease the current of the power to be transferred by increasing the duty cycle of the switching control circuitry.

2. The apparatus of claim 1, wherein the power extractor further includes:

switching circuitry to control the power transfer circuitry; and

switching control circuitry to control a duty cycle of the switching circuitry, wherein the power change analysis circuitry operates in different modes and wherein in an ordinary operating mode, under some conditions, the power analysis circuitry causes the power transfer circuitry to

decrease the current of the power to be transferred by decreasing the duty cycle of the switching control circuitry, and

increase the current of the power to be transferred by increasing the duty cycle of the switching control circuitry.

3. The apparatus of claim 2, wherein the power transfer circuitry includes a first energy transfer circuit connected to the first node to continuously transfer energy, a second energy transfer circuit connected to the second node to continuously transfer energy, and an intermediate energy transfer circuit connected between the first and second energy transfer circuits to discontinuously transfer energy between the first and second energy transfer circuits.

4. The apparatus of claim 3, wherein the switching circuitry is to modulate voltages at a third node between the first and intermediate energy transfer circuits, and at a fourth node between the intermediate and second energy transfer circuits.

5. The apparatus of claim 3, wherein a frequency of operation of the switching circuitry is dynamically adjusted to maximize efficiency of power transfer between the first and second nodes.

6. The apparatus of claim 3, wherein the first and second energy transfer circuits each includes an inductor and the intermediate energy transfer circuit includes capacitors.

7. The apparatus of claim 3, wherein the first, second, and intermediate energy transfer circuits each include at least one capacitor.

8. The apparatus of claim 1, wherein the power transfer circuitry includes a first energy transfer circuit connected to the first node to continuously transfer energy, a second energy transfer circuit connected to the second node to continuously transfer energy, and an intermediate energy transfer circuit connected between the first and second energy transfer circuits to discontinuously transfer energy between the first and second energy transfer circuits.

9. The apparatus of claim 8, wherein the switching circuitry is to modulate voltages at a third node between the first and intermediate energy transfer circuits, and at a fourth node between the intermediate and second energy transfer circuits.

10. The apparatus of claim 8, wherein the first and second energy transfer circuits each includes an inductor and the intermediate energy transfer circuit includes capacitors.

11. The apparatus of claim 8, wherein the first, second, and intermediate energy transfer circuits each include at least one capacitor.

12. The apparatus of claim 1, further comprising a power source to provide power to the first node and power analysis circuitry seeks to control the duty cycle of the switching circuitry to maximize power transfer through the power transfer circuitry given conditions beyond the control of the power analysis circuitry and given inefficiencies of the apparatus.

13. The apparatus of claim 12, wherein the power source is a photovoltaic power source and one of the conditions beyond the control of the power analysis circuitry is an amount of sunlight on the power source.

14. The apparatus of claim 12, wherein there is at least one intermediate node between the power source and the first node.

15. The apparatus of claim 1, further comprising a load coupled to the second node.

16. The apparatus of claim 1, wherein the power change analysis circuitry is to detect a power slope and a voltage slope.

17. The apparatus of claim 1, wherein the power extractor operates to seek to match an input impedance of the power transfer circuitry with an output impedance of a power source.

18. The apparatus of claim 1, the power change analysis circuitry to further filter rapid power changes and voltage changes at the first node.

19. An system comprising:

a power source;

a load; and

a power extractor coupled to the power source and the load, the power extractor to include;

power transfer circuitry to transfer power having a current between the power source and the load,

power change analysis circuitry to detect an instantaneous power change and a voltage change at the power source and at least partially control the current of the power to be transferred in response to the detected instantaneous power change and voltage change at the power source, the current to

decrease when the power change and the voltage change at the power source are both increasing, and when the power change and the voltage change at the power source are both decreasing, and

increase when the power change at the power source is decreasing and the voltage change at the power source is increasing, and when the power change at the power source is increasing and the voltage change at the power source is decreasing,

switching circuitry to control the power transfer circuitry; and

switching control circuitry to control a duty cycle of the switching circuitry, wherein the power change analysis circuitry operates in different modes and wherein in an ordinary operating mode, under some conditions, the power analysis circuitry causes the power transfer circuitry to

increase the current of the power to be transferred by decreasing the duty cycle of the switching control circuitry, and

decrease the current of the power to be transferred by increasing the duty cycle of the switching control circuitry.

20. The system of claim 19, wherein the power extractor further includes:

switching circuitry to control the power transfer circuitry; and

switching control circuitry to control a duty cycle of the switching circuitry, wherein the power change analysis circuitry operates in different modes and wherein in an ordinary operating mode, under some conditions, the power analysis circuitry causes the power transfer circuitry to

decrease the current of the power to be transferred by decreasing the duty of the switching control circuitry, and

increase the current of the power to be transferred by increasing the duty cycle of the switching control circuitry.

21. The system of claim 20, wherein the power transfer circuitry includes a first energy transfer circuit connected to the power source to continuously transfer energy, a second energy transfer circuit connected to the load to continuously transfer energy, and an intermediate energy transfer circuit connected between the first and second energy transfer circuits to discontinuously transfer energy between the first and second energy transfer circuits.

22. The system of claim 21, wherein the switching circuitry is to modulate voltages at a first node between the first and intermediate energy transfer circuits, and at a second node between the intermediate and second energy transfer circuits.

23. The system of claim 21, wherein a frequency of operation of the switching circuitry is dynamically adjusted to maximize efficiency of power transfer between the power source and the load.

24. The system of claim 19, wherein the power transfer circuitry includes a first energy transfer circuit connected to the power source to continuously transfer energy, a second energy transfer circuit connected to the load to continuously transfer energy, and an intermediate energy transfer circuit connected between the first and second energy transfer circuits to discontinuously transfer energy between the first and second energy transfer circuits.

25. The system of claim 19, the power change analysis circuitry to further filter rapid power changes and voltage changes at the first node.