SYSTEM AND METHOD FOR PROVIDING A PIEZOELECTRIC ELECTROMAGNETIC HYBRID VIBRATING ENERGY HARVESTER

• US 20090261689A1
• Filed: 04/22/2008
• Published: 10/22/2009
• Est. Priority Date: 04/22/2008
• Status: Active Grant

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Fang, Hua Bin
• Granted Patent: US 7,928,634 B2
• Time in Patent Office: Days
• US Class Current: 310/319
• CPC Class Codes: H02J 7/32 for charging batteries from a charging set comprising a non-electric prime mover rotating at constant speed
• CPC Class Codes: H02K 35/02 with moving magnets and stationary coil systems
• CPC Class Codes: H02K 53/00 Alleged dynamo-electric perpetua mobilia
• 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

A system and method are disclosed for providing a piezoelectric electromagnetic hybrid vibrating energy harvester. The invention comprises a piezoelectric vibrating energy harvesting device that harvests electrical energy from vibrations using a piezoelectric effect. The invention also comprises an electromagnetic vibrating energy harvesting device that simultaneously harvests electrical energy from the same vibrations using electromagnetic induction. A permanent magnet mass mounted on a cantilever host beam of the piezoelectric vibrating energy harvesting device provides a variable magnetic flux to a fixed conductive winding of the electromagnetic vibrating energy harvesting device when the permanent magnet mass vibrates.

Claims

1. An apparatus that comprises a piezoelectric electromagnetic hybrid vibrating energy harvester.

2. The apparatus as claimed in claim 1 wherein the piezoelectric electromagnetic hybrid vibrating energy harvester comprises:

a piezoelectric vibrating energy harvesting device that comprises a permanent magnet mass; and

an electromagnetic vibrating energy harvesting device that receives a variable magnetic flux from the permanent magnet mass when the permanent magnet mass moves.

3. The apparatus as claimed in claim 2 wherein the apparatus simultaneously harvests electrical energy from the piezoelectric vibrating energy harvesting device and from the electromagnetic vibrating energy harvesting device.

4. The apparatus as claimed in claim 2 wherein the piezoelectric vibrating energy harvesting device comprises:

a cantilever host beam having a first end attached to a fixed end structure;

a layer of piezoelectric material attached to the cantilever host beam; and

wherein the permanent magnet mass is attached to a second free end of the cantilever host beam.

5. The apparatus as claimed in claim 4 wherein the piezoelectric vibrating energy harvesting device further comprises:

a first rectifier circuit and a first electrical connection that connects a first electrical output of the layer of piezoelectric material to a first input of the first rectifier circuit and a second electrical connection that connects a second electrical output the layer of piezoelectric material to a second input of the first rectifier circuit; and

a power storage unit that is connected to an output of the first rectifier circuit that receives and stores electrical energy created due to the vibrations of the layer of piezoelectric material.

6. The apparatus as claimed in claim 4 wherein the electromagnetic vibrating energy harvesting device comprises:

a fixed conductive winding located adjacent to the permanent magnet mass located on the second free end of the cantilever host beam; and

wherein the fixed conductive winding receives a variable magnetic flux from the permanent magnet mass when the permanent magnet mass moves.

7. The apparatus as claimed in claim 6 wherein the conductive winding comprises a plurality of loops of conductive wire.

8. The apparatus as claimed in claim 6 wherein the fixed conductive winding is one of:

located below the permanent magnet mass and located above the permanent magnet mass.

9. The apparatus as claimed in claim 6 wherein the electromagnetic vibrating energy harvesting device further comprises:

a second rectifier circuit and a third electrical connection that connects a first electrical output of the conductive winding to a first input of the second rectifier circuit and a fourth electrical connection that connects a second electrical output of the conductive winding to a second input of the second rectifier circuit; and

a power storage unit that is connected to an output of the second rectifier circuit that receives and stores electrical energy created due to electromotance that is induced in the conductive winding due to the relative motion of the permanent magnet mass with respect to the conductive winding.

10. The apparatus as claimed in claim 2 wherein

the piezoelectric vibrating energy harvester device has an output performance that produces a high voltage and a low current;

the electromagnetic vibrating energy harvester device has an output performance that produces a low voltage and a high current; and

the piezoelectric electromagnetic hybrid vibrating energy harvester has an output performance that produces a high voltage and a high current.

11. The apparatus as claimed in claim 1 wherein the piezoelectric electromagnetic hybrid vibrating energy harvester comprises:

a piezoelectric vibrating energy harvesting device that comprises a permanent magnet attached to a vibrating portion of the piezoelectric vibrating energy harvesting device; and

an electromagnetic vibrating energy harvesting device that receives a variable magnetic flux from the permanent magnet when the permanent magnet moves.

12. The apparatus as claimed in claim 11 wherein the apparatus simultaneously harvests electrical energy from the piezoelectric vibrating energy harvesting device and from the electromagnetic vibrating energy harvesting device.

13. A method of harvesting electrical energy from vibrations, said method comprising the steps of:

harvesting electrical energy using a piezoelectric vibrating energy harvesting device; and

simultaneously harvesting electrical energy using an electromagnetic vibrating energy harvesting device.

14. The method as claimed in claim 13, further comprising the steps of:

harvesting electrical energy using a piezoelectric vibrating energy harvesting device that comprises a permanent magnet mass; and

simultaneously harvesting electrical energy using an electromagnetic vibrating energy harvesting device that receives a variable magnetic flux from the permanent magnet mass when the permanent magnet mass moves.

15. The method as claimed in claim 14 wherein the step of harvesting electrical energy using a piezoelectric vibrating energy harvesting device that comprises a permanent magnet mass comprises:

attaching a first end of a cantilever host beam to a fixed end structure;

attaching a layer of piezoelectric material to the cantilever host beam;

attaching the permanent magnet mass to a second free end of the cantilever host beam;

transforming vibrational energy in the layer of piezoelectric material to electrical energy; and

storing the electrical energy created due to the vibrations of the layer of piezoelectric material.

16. The method as claimed in claim 15 wherein the step of simultaneously harvesting electrical energy using an electromagnetic vibrating energy harvesting device that receives a variable magnetic flux from the permanent magnet mass when the permanent magnet mass moves comprises the steps of:

placing a fixed conductive winding adjacent to the permanent magnet mass located on the second free end of the cantilever host beam; and

receiving in the fixed conductive winding a variable magnetic flux from the permanent magnet mass when the permanent magnet mass moves.

17. The method as claimed in claim 16 wherein the fixed conductive winding comprises a plurality of loops of conductive wire.

18. The method as claimed in claim 16 wherein the fixed conductive winding is one of:

located below the permanent magnet mass and located above the permanent magnet mass.

19. A piezoelectric electromagnetic hybrid vibrating energy harvester comprising:

a piezoelectric vibrating energy harvesting device that comprises a layer of piezoelectric material attached to a cantilever host beam having a first end attached to a fixed end structure and that comprises a permanent magnet mass attached to a second free end of the cantilever host beam; and

an electromagnetic vibrating energy harvesting device that comprises a fixed conductive winding located adjacent to the permanent magnet mass that receives a variable magnetic flux from the permanent magnet mass when the permanent magnet mass moves.

20. The piezoelectric electromagnetic hybrid vibrating energy harvester as claimed in claim 19 wherein the piezoelectric vibrating energy harvesting device harvests electrical energy from vibrations using a piezoelectric effect and the electromagnetic vibrating energy harvesting device simultaneously harvests electrical energy from vibrations using electromagnetic induction.