CN106160571B - Multi-direction broad-band piezoelectricity oscillating generating set - Google Patents
Multi-direction broad-band piezoelectricity oscillating generating set Download PDFInfo
- Publication number
- CN106160571B CN106160571B CN201610442193.5A CN201610442193A CN106160571B CN 106160571 B CN106160571 B CN 106160571B CN 201610442193 A CN201610442193 A CN 201610442193A CN 106160571 B CN106160571 B CN 106160571B
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- China
- Prior art keywords
- cantilever beam
- piezoelectric patches
- conversion chip
- generating set
- input terminal
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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- 238000006243 chemical reaction Methods 0.000 claims description 30
- 238000004146 energy storage Methods 0.000 claims description 8
- 239000003990 capacitor Substances 0.000 claims description 7
- 101100112673 Rattus norvegicus Ccnd2 gene Proteins 0.000 claims description 3
- 241000276425 Xiphophorus maculatus Species 0.000 claims description 3
- 238000003780 insertion Methods 0.000 claims description 2
- 230000037431 insertion Effects 0.000 claims description 2
- 230000005284 excitation Effects 0.000 description 9
- 238000005516 engineering process Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 3
- 238000010248 power generation Methods 0.000 description 3
- 229910000838 Al alloy Inorganic materials 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 238000003306 harvesting Methods 0.000 description 2
- 239000007769 metal material Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000012536 storage buffer Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
- H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
- H02N2/18—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing electrical output from mechanical input, e.g. generators
- H02N2/181—Circuits; Control arrangements or methods
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02N—ELECTRIC MACHINES NOT OTHERWISE PROVIDED FOR
- H02N2/00—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction
- H02N2/18—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing electrical output from mechanical input, e.g. generators
- H02N2/186—Vibration harvesters
Abstract
A kind of multi-direction broad-band piezoelectricity oscillating generating set provided by the invention, including the first cantilever beam and the second cantilever beam, one end fixed setting of first cantilever beam, one end detachable connection of the other end and the second cantilever beam, the other end of second cantilever beam is free end and is provided with mass block, there is angle, first cantilever beam and the second cantilever beam are both provided with piezoelectric patches between first cantilever beam and the second cantilever beam；Multidirectional vibrational energy can be collected and change into electric energy, and can effectively widen collection of energy frequency band, improve the collection efficiency of vibrational energy.
Description
Technical field
The present invention relates to a kind of power generator more particularly to a kind of multi-direction broad-band piezoelectricity oscillating generating sets.
Background technology
With the fast development of chip and ultralow job number integrated circuit technique so that wireless sensor network extensive use,
Since wireless sensor network node distribution is numerous, become technical barrier for the power supply of wireless sensor network node, tradition
Technology uses battery powered, it is necessary to periodically replace battery for wireless sensor network node, causes a large amount of waves of man power and material
Take, especially under severe working condition so that battery altering is more preferably complicated or even is difficult to.
In order to solve the above-mentioned technical problem, people gradually propose piezoelectric vibration power generation technology, and this technology has work
Stablize, make simple and cleanliness without any pollution, therefore, piezoelectric vibration power generation technology is using more and more extensive, but existing piezoelectricity
Vibration generating device has as a drawback that：Existing piezoelectricity oscillating generating set has higher output electricity at resonant frequency
Pressure, and off-resonance frequency is once vibrated, output voltage then declines suddenly, and existing piezoelectricity oscillating generating set is only to certain
The vibrational excitation in a direction is more sensitive, and under actual working condition, and vibration has the characteristics that wideband and multidirectional, leads
The inefficiency of existing piezoelectric generating device collection of energy is caused, practical application request can not be met.
It is, therefore, desirable to provide a kind of new piezoelectric generating device, can adapt to multi-direction and vibration frequency in practical applications
The wider environment of band improves vibration energy harvesting efficiency.
The content of the invention
In view of this, the object of the present invention is to provide a kind of multi-direction broad-band piezoelectricity oscillating generating set, actually should
It can adapt to environment multi-direction and that vibration frequency band is wider in, improve vibration energy harvesting efficiency.
A kind of multi-direction broad-band piezoelectricity oscillating generating set provided by the invention, including the first cantilever beam and the second cantilever
One end detachable connection of beam, one end fixed setting of first cantilever beam, the other end and the second cantilever beam, the second cantilever
The other end of beam is free end and is provided with mass block, has angle between first cantilever beam and the second cantilever beam, described
First cantilever beam and the second cantilever beam are both provided with piezoelectric patches.
Further, the angle theta of first cantilever beam and the second cantilever beam is 90 ° of 180 ° of ＜ θ ＜.
Further, the angle of first cantilever beam and the second cantilever beam is 135 °.
Further, first cantilever beam and the second cantilever beam pass through a connection piece detachable connection.
Further, the connector is column structure, and the side wall of the connector radially sinks to forming multiple embedded grooves,
The end of first cantilever beam and the second cantilever beam is embedded in embedded groove.
Further, the embedded groove is uniformly distributed along the circumferencial direction of connector.
Further, first cantilever beam and the second cantilever beam are platy structure, first cantilever beam and the second cantilever
The upper and lower surface of beam is both provided with piezoelectric patches.
Further, further include energy storage conversion circuit, the energy storage conversion circuit include rectification circuit U1, storage capacitor C1 with
And conversion chip U2；
Input terminal PZ2 and the output terminal of input terminal PZ1 and the piezoelectric patches connection of the conversion chip U2, the rectification circuit
The input terminal of U1 and the output terminal of piezoelectric patches connect, and the positive output end of rectification circuit U1 passes through the defeated of capacitance C3 and conversion chip U2
Enter Vin1 is held to connect, the negative output terminal of rectification circuit U1 is connected by capacitance C2 with the input terminal Vin2 of conversion chip U2, described
The both ends of storage capacitor C1 are connected between the positive output end and negative output terminal of rectification circuit U1, the conversion chip U2's
Output end vo ut powers to the load.
Further, the conversion chip U2 is LTC3588-1 chips.
Beneficial effects of the present invention：The multi-direction broad-band piezoelectricity oscillating generating set of the present invention, can collect multi-direction
Vibrational energy and change into electric energy, and can effectively widen collection of energy frequency band, improve the collection efficiency of vibrational energy.
Description of the drawings
The invention will be further described with reference to the accompanying drawings and examples：
Fig. 1 is the structural diagram of the present invention.
Fig. 2 is the relational graph that the present invention encourages lower open-circuit voltage and excited frequency in the Y direction.
Fig. 3 relational graphs of open-circuit voltage and excited frequency under Z-direction excitation for the present invention.
Fig. 4 is the energy storage conversion circuit schematic diagram of the present invention.
Specific embodiment
Fig. 1 is the structural diagram of the present invention, and Fig. 2 is that the present invention encourages lower open-circuit voltage and excited frequency in the Y direction
Relational graph, Fig. 3 relational graphs of open-circuit voltage and excited frequency under Z-direction excitation for the present invention, as shown in the figure, the present invention provides
A kind of multi-direction broadband piezoelectricity oscillating generating set, a kind of multi-direction broadband piezoelectric vibration power generation dress provided by the invention
It puts, including the first cantilever beam 1 and the second cantilever beam 2, one end of first cantilever beam 1 fixed setting, fixed setting refers to the
One cantilever is fixedly mounted by fixing piece, for example special fixture, the modes such as wall is fixed on by screw；The other end and second hangs
One end detachable connection of arm beam 2, the other end of the second cantilever beam 2 for free end and are provided with mass block 3, and described first is outstanding
There is angle, 1 and second cantilever beam 2 of the first cantilever beam is both provided with piezoelectric patches 4, leads between 1 and second cantilever beam 2 of arm beam
Said structure is crossed, though the first cantilever beam and the second cantilever beam have large magnitude under smaller excitation, and even if not
Can equally have output under vibrational excitation on equidirectional, so as to effectively improve the vibrational energy of piezoelectricity oscillating generating set
Collection efficiency is measured, solve thes problems, such as can only just there is output under single direction excitation in traditional technology.
In the present embodiment, the angle theta of 1 and second cantilever beam 2 of the first cantilever beam is 90 ° of 180 ° of ＜ θ ＜, the first cantilever
The angle of 1 and second cantilever beam 2 of beam is in this angular range so that the present invention has higher efficiency of energy collection, it is preferable that
The angle of first cantilever beam, 1 and second cantilever beam 2 is 135 °, that is to say, that under general status, the first cantilever beam 1 and
When angle between two cantilever beams 2 is 135 °, no matter also it is horizontally oriented its in vertical direction and exports maximum, still, at certain
In some specific work condition environments, for example, clearly detected vibrational excitation direction or some operating modes under can not more than
The mode of stating is set, then can be adjusted accordingly the angle between two cantilevers according to actual condition, so that two cantilevers
Angle between beam is suitable for work condition environment.
In the present embodiment, 1 and second cantilever beam 2 of the first cantilever beam is passed through by 5 detachable connection of a connection piece
This structure, can aspect the first cantilever beam 1 and the second cantilever beam 2 are installed, it is even more important that connector is here
It is also used as mass block, the collective effect of connector and the mass block on the second cantilever beam 2 increases two under incentive action
The amplitude of cantilever beam further improves the collection efficiency of vibrational energy.
In the present embodiment, the connector 5 is column structure, and the side wall of the connector 5 radially sinks to being formed multiple
Embedded groove 6, the end of 1 and second cantilever beam 2 of the first cantilever beam are embedded in embedded groove 6, pass through this structure, Neng Goufang
Just two cantilever beams to be installed, what is more important is beneficial to be adjusted the angle between two cantilever beams, so as to
Enough there is stronger operating mode adaptability.
Preferably, the embedded groove 6 is uniformly distributed along the circumferencial direction of connector 5, in actual use, can be by insertion
Slot 6 is arranged to the numbers such as 8,16 or 32, the essence of the angle adjustment according to actual needs and between two cantilever beams
Exactness and determine, by said structure, be adjusted beneficial to the angle between two cantilever beams.
In the present embodiment, 1 and second cantilever beam 2 of the first cantilever beam is platy structure, first cantilever beam 1 and the
The upper and lower surface of two cantilever beams 2 is both provided with piezoelectric patches 4, by this structure, can effectively improve vibrational energy
Collection efficiency and the electric transformation of energy of raising, certainly, piezoelectric patches 4 uses existing piezoelectric patches, and has the structures such as output electrode,
It is connected by electrode and conducting wire with rectification storage circuit, for example piezoelectric ceramics piece, the first cantilever beam 1 and the second cantilever beam 2 use
Metal material, it is preferred to use copper product, connector 5 is equally using metal material, such as aluminium alloy.
In the present embodiment, energy storage conversion circuit is further included, the energy storage conversion circuit includes rectification circuit U1, storage capacitor
C1 and conversion chip U2；
Input terminal PZ2 and the output terminal of input terminal PZ1 and the piezoelectric patches connection of the conversion chip U2, the rectification circuit
The input terminal of U1 and the output terminal of piezoelectric patches connect, and the positive output end of rectification circuit U1 passes through the defeated of capacitance C3 and conversion chip U2
Enter Vin1 is held to connect, the negative output terminal of rectification circuit U1 is connected by capacitance C2 with the input terminal Vin2 of conversion chip U2, described
The both ends of storage capacitor C1 are connected between the positive output end and negative output terminal of rectification circuit U1, the conversion chip U2's
Output end vo ut powers to the load, wherein, input terminal PZ2 and input terminal PZ1 and the one of piezoelectric patches of conversion chip U2
Output terminal connection, and the output terminal of other piezoelectric patches is then connected to the input terminal of rectification circuit U1, and rectification circuit U1 is full-bridge
Formula rectification circuit, since the energy of piezoelectric patches output is alternating current, and the characteristic of different piezoelectric patches is different, each piezoelectric patches
Output voltage, electric current and phase differ, therefore, when all piezoelectric patches all concatenation or it is in parallel by way of it is direct
When being connected to conversion chip U1, whole output power will be caused to reduce, by said structure, even if piezoelectric patches more than two,
One of piezoelectric patches is only directly connected in conversion chip U1, the output terminal of other piezoelectric patches is defeated with rectification circuit U1
Enter end connection, then acted on by the energy storage buffer of storage capacitor C1, the above problem is can effectively solve the problem that, so as to effectively keep away
Exempt from energy loss, improve the output power of the present invention.
Further, the conversion chip U2 is LTC3588-1 chips
With specific example, the present invention will be described below：
In this example, two cantilever beams are made of copper, and piezoelectric patches uses PZT-51 piezoelectric ceramics, and connector uses
Aluminium alloy, mass block are then made of wolfram steel, design parameter such as following table in instances：
Using the parameter in upper table, after test simulation, Fig. 2 and Fig. 3 analogous diagrams are drawn, as can be seen from Figure 2：When
When excitation comes from the vibration of Y-direction, i.e. horizontal direction, there are two peak values for output of the invention tool：One class resonant frequency 8.5Hz has
There is peak value 77V/g, have peak value 24.9V/g in second order resonant frequency 24.7Hz；It can be seen that in Fig. 3：Z-direction is come from when encouraging,
I.e. the vibration of vertical direction when, output of the invention tool is there are two peak value：One class resonant frequency 9.2Hz has peak value 140.2V/
G has peak value 22.9V/g in second order resonant frequency 29Hz；It can to sum up learn：The present invention in practical applications, in different directions
Vibrational excitation under, all at least tool there are two output peak value, that is to say, that the present invention effectively increase energy collection frequency band
Width, and then the collection efficiency of vibrational energy is had submitted, and also electric energy conversion efficiency is high.
Finally illustrate, the above embodiments are merely illustrative of the technical solutions of the present invention and it is unrestricted, although with reference to compared with
The present invention is described in detail in good embodiment, it will be understood by those of ordinary skill in the art that, it can be to the skill of the present invention
Art scheme is modified or replaced equivalently, and without departing from the objective and scope of technical solution of the present invention, should all be covered at this
Among the right of invention.
Claims (4)
1. a kind of multi-direction broad-band piezoelectricity oscillating generating set, it is characterised in that：Including the first cantilever beam and the second cantilever beam,
One end detachable connection of one end fixed setting of first cantilever beam, the other end and the second cantilever beam, the second cantilever beam
The other end free end and to be provided with mass block, there is angle between first cantilever beam and the second cantilever beam, described the
One cantilever beam and the second cantilever beam are both provided with piezoelectric patches；The angle of first cantilever beam and the second cantilever beam is 135 °；Institute
The first cantilever beam and the second cantilever beam are stated by a connection piece detachable connection, the connector is column structure, the company
The side wall of fitting radially sinks to forming multiple embedded grooves, and the end of first cantilever beam and the second cantilever beam is embedded in insertion
In slot.
2. multi-direction broad-band piezoelectricity oscillating generating set according to claim 1, it is characterised in that：The embedded groove is along even
The circumferencial direction of fitting is uniformly distributed.
3. according to multi-direction broad-band piezoelectricity oscillating generating set described in claim 1-2 any claims, it is characterised in that：
First cantilever beam and upper surface and following table that the second cantilever beam is platy structure, first cantilever beam and the second cantilever beam
Face is both provided with piezoelectric patches.
4. multi-direction broad-band piezoelectricity oscillating generating set according to claim 1, it is characterised in that：Further include energy storage conversion
Circuit, the energy storage conversion circuit include rectification circuit U1, storage capacitor C1 and conversion chip U2；The piezoelectric patches is more
It is a,
The input terminal PZ2 and input terminal PZ1 of the conversion chip U2 is connected with the output terminal of one of piezoelectric patches, the rectification
The input terminal of circuit U 1 is connected with removing the output terminal of other piezoelectric patches beyond the piezoelectric patches being directly connected to conversion chip U2,
The positive output end of rectification circuit U1 is connected by capacitance C3 with the input terminal Vin1 of conversion chip U2, the negative output of rectification circuit U1
End is connected by capacitance C2 with the input terminal Vin2 of conversion chip U2, and the both ends of the storage capacitor C1 are connected to rectified current
Between the positive output end and negative output terminal of road U1, the output end vo ut of the conversion chip U2 powers to the load；
The conversion chip U2 is LTC3588-1 chips.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610442193.5A CN106160571B (en) | 2016-06-20 | 2016-06-20 | Multi-direction broad-band piezoelectricity oscillating generating set |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201610442193.5A CN106160571B (en) | 2016-06-20 | 2016-06-20 | Multi-direction broad-band piezoelectricity oscillating generating set |
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| Publication Number | Publication Date |
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| CN106160571A CN106160571A (en) | 2016-11-23 |
| CN106160571B true CN106160571B (en) | 2018-05-22 |
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| CN201610442193.5A Expired - Fee Related CN106160571B (en) | 2016-06-20 | 2016-06-20 | Multi-direction broad-band piezoelectricity oscillating generating set |
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| CN111614285A (en) * | 2020-06-03 | 2020-09-01 | 南京航空航天大学 | Asymmetric cantilever beam type piezoelectric broadband vibration energy collecting device |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102170246A (en) * | 2011-04-01 | 2011-08-31 | 重庆大学 | Vibrating type miniature wind driven generator with flexible beam structure |
| CN103066884A (en) * | 2012-12-24 | 2013-04-24 | 成都理工大学 | Self-tuning type frequency conversion power generation device and method |
| CN103227586A (en) * | 2013-04-12 | 2013-07-31 | 南京航空航天大学 | Branch cantilever beam vibration generator and power generation method thereof |
| CN203608112U (en) * | 2013-10-16 | 2014-05-21 | 浙江工业大学 | Miniature piezoelectric-type energy collector based on low-frequency environment vibration and driving |
| CN103872946A (en) * | 2014-03-26 | 2014-06-18 | 太原理工大学 | Vibration pick-up structure for linear multi-freedom-degree low-frequency vibration energy collector |
| CN205283430U (en) * | 2016-01-02 | 2016-06-01 | 宁波大学 | Hard and soft composite beam wind power generation device |
-
2016
- 2016-06-20 CN CN201610442193.5A patent/CN106160571B/en not_active Expired - Fee Related
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102170246A (en) * | 2011-04-01 | 2011-08-31 | 重庆大学 | Vibrating type miniature wind driven generator with flexible beam structure |
| CN103066884A (en) * | 2012-12-24 | 2013-04-24 | 成都理工大学 | Self-tuning type frequency conversion power generation device and method |
| CN103227586A (en) * | 2013-04-12 | 2013-07-31 | 南京航空航天大学 | Branch cantilever beam vibration generator and power generation method thereof |
| CN203608112U (en) * | 2013-10-16 | 2014-05-21 | 浙江工业大学 | Miniature piezoelectric-type energy collector based on low-frequency environment vibration and driving |
| CN103872946A (en) * | 2014-03-26 | 2014-06-18 | 太原理工大学 | Vibration pick-up structure for linear multi-freedom-degree low-frequency vibration energy collector |
| CN205283430U (en) * | 2016-01-02 | 2016-06-01 | 宁波大学 | Hard and soft composite beam wind power generation device |
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| CN106160571A (en) | 2016-11-23 |
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