Power harvesting

• US 10,205,084 B2
• Filed: 03/31/2016
• Issued: 02/12/2019
• Est. Priority Date: 03/31/2016
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Vaidya, Vaibhav, Kim, Suhwan
• Primary Examiner(s): Parihar, Suchin
• Application Number:
  US15/087,613
• Publication Number:
  US 20170288415A1
• Time in Patent Office: 1,048 Days
• Field of Search: 320138
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/345 using capacitors as storage or buffering devices
• CPC Class Codes: H02N 2/181 Circuits; Control arrangements or methods
• CPC Class Codes: H02N 2/186 Vibration harvesters
• CPC Class Codes: H10N 30/306 Cantilevers

Abstract

Techniques for harvesting electrical energy from a plurality of harvesters is disclosed. An example energy harvesting system includes a plurality of harvesters and a signal conditioning circuit selectively coupled to an output of each of the plurality of harvesters. The system also includes an energy storage element coupled to the output of the signal conditioning circuit to be charged by the plurality of harvesters through the signal conditioning circuit. The system also includes a controller to discharge a selected harvester to the signal conditioning circuit when an output of the selected harvester triggers a charge collection.

Claims

1. An energy harvesting system, comprising:

a plurality of harvesters a signal conditioning circuit selectively coupled to an output of each of the plurality of harvesters;

an energy storage element coupled to an output of the signal conditioning circuit and to be charged by the plurality of harvesters through the signal conditioning circuit; and

a controller to detect a charge level for each of the plurality of harvesters and discharge a selected harvester of the plurality of harvesters by coupling the selected harvester to the signal conditioning circuit based on the charge level of the selected harvester.

2. The energy harvesting system of claim 1, wherein the plurality of harvesters comprise at least one harvester configured to convert vibrational energy into electrical energy.

3. The energy harvesting system of claim 1, wherein the plurality of harvesters comprises a first harvester responsive to vibrations occurring in a first plane and a second harvester responsive to vibrations occurring in a second plane.

4. The energy harvesting system of claim 1, wherein the plurality of harvesters comprises a first harvester to resonate at a first vibrational frequency and a second harvester to resonate at a second vibrational frequency.

5. The energy harvesting system of claim 1, wherein the plurality of harvesters comprises a first set of harvesters and a second set of harvesters, the first set of harvesters comprising harvesters that resonate at a plurality of vibrational frequencies, and the second set of harvesters oriented to be responsive to a plurality of planes of vibration.

6. The energy harvesting system of claim 1, wherein the controller is to discharge the selected harvester when the charge level reaches a local maxima.

7. The energy harvesting system of claim 1, wherein the controller is to discharge the selected harvester when the charge level reaches a threshold.

8. The energy harvesting system of claim 1, wherein, after the selected harvester is discharged, the controller is to couple the signal conditioning circuit to the energy storage element to transfer stored energy from the signal conditioning circuit to the energy storage element.

9. The energy harvesting system of claim 1, wherein, after the selected harvester is discharged and before the signal conditioning circuit is discharged to the energy storage element, the controller is to discharge an other harvester of the plurality of harvesters to the signal conditioning circuit based on the charge level of the other harvester.

10. The energy harvesting system of claim 1, wherein the signal conditioning circuit is an inductor.

11. A method of charging a battery, comprising:

detecting a voltage generated by each harvester in a plurality of harvesters;

detecting a trigger condition for a selected harvester of the plurality of harvesters based on the voltage detected for the selected harvester;

discharging the selected harvester by coupling the selected harvester to a signal conditioning circuit in response to the trigger condition; and

discharging the signal conditioning circuit to the battery.

12. The method of claim 11, wherein the plurality of harvesters comprise at least one harvester configured to convert vibrational energy into electrical energy.

13. The method of claim 11, wherein the plurality of harvesters comprises a first harvester responsive to vibrations occurring in a first plane and a second harvester responsive to vibrations occurring in a second plane.

14. The method of claim 11, wherein the plurality of harvesters comprises a first harvester to resonate at a first vibrational frequency and a second harvester to resonate at a second vibrational frequency.

15. The method of claim 11, wherein the plurality of harvesters comprises a first set of harvesters and a second set of harvesters, the first set of harvesters comprising harvesters that resonate at a plurality of vibrational frequencies, and the second set of harvesters oriented to be responsive to a plurality of planes of vibration.

16. The method of claim 11, wherein detecting the trigger condition for the selected harvester comprises detecting a local maxima in the voltage generated by the selected harvester.

17. The method of claim 11, wherein detecting the trigger condition for the selected harvester comprises detecting that the voltage generated by selected harvester has reached a threshold.

18. The method of claim 11, wherein discharging the signal conditioning circuit to the battery comprises coupling the signal conditioning circuit to the battery after the selected harvester is discharged and before discharging an other harvester of the plurality of harvesters to the signal conditioning circuit.

19. The method of claim 11, comprising discharging an other harvester of the plurality of harvesters to the signal conditioning circuit after the selected harvester is discharged and before the signal conditioning circuit is discharged to the battery.

20. The method of claim 11, wherein the signal conditioning circuit is an inductor.

21. An energy harvesting circuit comprising:

an plurality of inputs to receive electrical energy from a plurality of harvesters;

a signal conditioning circuit to store energy received from the plurality of harvesters before transferring the stored energy to a battery;

a plurality of switches to selectively couple each of the plurality of harvesters to the signal conditioning circuit; and

a controller to detect a charge level for each of the plurality of harvesters and discharge a selected harvester of the plurality of harvesters by controlling the plurality of switches to couple the selected harvester to the signal conditioning circuit when a voltage based on the charge level of the selected harvester triggers a charge collection.

22. The energy harvesting circuit of claim 21, wherein the plurality of harvesters comprise at least one harvester configured to convert vibrational energy into electrical energy.

23. The energy harvesting circuit of claim 21, wherein the plurality of harvesters comprises a first harvester responsive to vibrations occurring in a first plane and a second harvester responsive to vibrations occurring in a second plane.

24. The energy harvesting circuit of claim 21, wherein the plurality of harvesters comprises a first harvester to resonate at a first vibrational frequency and a second harvester to resonate at a second vibrational frequency.

25. The energy harvesting circuit of claim 21, wherein the plurality of harvesters comprises a first set of harvesters and a second set of harvesters, the first set of harvesters comprising harvesters that resonate at a plurality of vibrational frequencies, and the second set of harvesters oriented to be responsive to a plurality of planes of vibration.