CN107332462B - The self-powered piezoelectric vibration energy that can track maximum power point extracts circuit - Google Patents
The self-powered piezoelectric vibration energy that can track maximum power point extracts circuit Download PDFInfo
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- CN107332462B CN107332462B CN201710612813.XA CN201710612813A CN107332462B CN 107332462 B CN107332462 B CN 107332462B CN 201710612813 A CN201710612813 A CN 201710612813A CN 107332462 B CN107332462 B CN 107332462B
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- 239000000284 extract Substances 0.000 title claims abstract description 7
- 239000003990 capacitor Substances 0.000 claims description 59
- 238000003860 storage Methods 0.000 claims description 22
- 238000000605 extraction Methods 0.000 description 11
- 238000010586 diagram Methods 0.000 description 7
- 230000007423 decrease Effects 0.000 description 4
- 230000001360 synchronised effect Effects 0.000 description 4
- 238000013461 design Methods 0.000 description 3
- 230000005611 electricity Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000004891 communication Methods 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000011217 control strategy Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
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- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004146 energy storage Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 238000003306 harvesting Methods 0.000 description 1
- 238000001566 impedance spectroscopy Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
- 238000013519 translation Methods 0.000 description 1
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- 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
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- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
- G05F1/00—Automatic systems in which deviations of an electric quantity from one or more predetermined values are detected at the output of the system and fed back to a device within the system to restore the detected quantity to its predetermined value or values, i.e. retroactive systems
- G05F1/66—Regulating electric power
- G05F1/67—Regulating electric power to the maximum power available from a generator, e.g. from solar cell
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- General Electrical Machinery Utilizing Piezoelectricity, Electrostriction Or Magnetostriction (AREA)
Abstract
The circuit control module that the self-powered piezoelectric vibration energy that can track maximum power point provided by the invention extracts circuit is made of discrete analog circuit device, the role of comparator and switch is served as using two triodes, maximum power point can successfully be captured and complete the collection of piezoelectric energy, and without additional devices such as programmable controllers.Therefore, the advantages which has low-power consumption, and impedance is independent, self-starting, is not necessarily to battery.
Description
Technical field
The present invention relates to piezoelectric energies to extract field, can track maximum power more particularly, to one kind is self-powered
The piezoelectric vibration energy of point extracts circuit.
Background technique
In recent years, the development of wireless sensor and wireless communication network node obtains great concern, and has become one
Big research hotspot.Wireless sensor is widely portable to building safety detection with wireless communication network node, environmental Kuznets Curves are surveyed
It examines, the scenes such as smart home, animal locating and tracking.But as the rapid growth of node device quantity and size gradually become
Small and inserting knot position distribution is dispersed further, and node power is gradually shown using this conventional technique scheme of chemical cell
Its limitation and shortcoming.Since the service life of chemical cell is limited, and frequent charging is needed, battery is carried out again
Secondary charging or replacement battery, become a great problem.
And with the common progress of low-power Electronic Design and low-power electronic manufacture, wireless sensor with communicate
The power consumption of network node further decreases, can be down to 10 to 100 μ W.Therefore, the piezoelectric effect that can use piezoelectric material will be outer
The ubiquitous vibrational energy in boundary is converted into electric energy, provides enough electric energy, this technical solution, referred to as piezoelectricity for node work
Energy collection technology, the element used are piezoelectric energy collector (piezoelectric energy harvester).
What it is due to the output of piezoelectric energy collector is alternating current, and its output impedance is in capacitive.In order to piezoelectric energy
It is stored and is made full use of, circuit needs a rectification interface circuit, and the alternating current of output is converted into be suitble to save
The direct current that point uses.Classical rectification interface circuit is that half-wave or full-wave rectification bridge are followed by storage capacitor, although this side
Case structure is simple, can export basicly stable DC current, but energy extraction efficiency is low.In order to overcome this deficiency,
Guyomar, Lefeuvre, Richard team propose a kind of referred to as SSHI (Synchronized Switch Harvesting
With Inductor) high efficiency nonlinear Energy extraction circuit be subject to appropriate with the auxiliary of inductance and synchronous switch
Control strategy reduces the charge and discharge time of the inner clip capacitor of piezoelectric energy collector and increases the charging time to storage capacitor,
To improve energy extraction efficiency.
Above classical circuit and SSHI circuit will obtain maximum Energy extraction power, it is also necessary to which external load meets resistance
Resist matched condition, but since external load is all specifically to apply, such as: sensor, the electronic equipments such as radiofrequency launcher are born
The impedance of load can not be changed, and above-mentioned interface circuit is difficult to meet impedance matching condition, in this regard, Richard et al. is proposed
Independent synchronous charge-extraction SECE (the Synchronous Electric Change Extraction) circuit of impedance, it was also proposed that
Realize using Buck-Boost step-down/up type translation circuit impedance independence.However only to realize impedance only for these circuits
Vertical, there is no the targets for veritably reaching impedance matching or impedance self-adaptive.
For the matched problem of resolved impedance spectroscopy, maximized so that collecting power, MPPT maximum power point tracking MPPT (Maximum
Power Point Tracking) technology is suggested.Currently, realizing that the algorithm of MPPT technique has hill-climbing algorithm and FOCV
Two kinds of (Fractional Open Circuit Voltage), on the mainstream implementation of algorithm, the former needs microprocessor
Etc. ancillary equipments monitored in real time and adjusted, the latter need auxiliary capacitor etc. come measure piezoelectricity open-circuit voltage in advance and obtain
Half value.Above implementation requires external accessory power supply, cannot achieve really without battery and complete self-powered.
Summary of the invention
The present invention is that the maximum power point tracking technology more than solving needs ancillary equipment to be monitored adjusting, cannot achieve
Self-powered technological deficiency provides a kind of self-powered piezoelectric vibration energy extraction circuit that can track maximum power point.
To realize the above goal of the invention, the technical solution adopted is that:
The self-powered piezoelectric vibration energy extraction circuit that can track maximum power point, including piezoelectric energy collector,
Full-wave rectification bridge, storage capacitor Ci, passive high three-way filter and circuit control module；
Wherein the positive output end of piezoelectric energy collector, negative output terminal be in respectively with full-wave rectification bridge diagonal end one,
Two connection of end, the end three of full-wave rectification bridge are grounded, the end four of full-wave rectification bridge and storage capacitor CiAnode connection, storage capacitor
CiCathode ground connection；
Passive high three-way filter includes capacitor CHPWith resistance RHP, capacitor CHPAnode connect with the end four of full-wave rectification bridge,
Capacitor CHPCathode pass through resistance RHPGround connection；
The circuit control module includes resistance R1, diode DHP, diode D1, capacitor C1, resistance R2, resistance R3, two poles
Pipe D2, PNP triode T1, diode D3With NPN triode T2；Wherein diode DHPCathode and capacitor CHPCathode connection, two
Pole pipe DHPPlus earth；Resistance R1One end and capacitor CHPCathode connection, resistance R1The other end and diode D1Sun
Pole connection, diode D1Cathode and capacitor C1Anode connection, capacitor C1Cathode ground connection；The PNP triode T1Transmitting
Pole and diode D2Cathode connection, diode D2Anode and capacitor C1Anode connection；PNP triode T1Base stage pass through
Resistance R2With capacitor CHPCathode connection, PNP triode T1Collector pass through resistance R3With NPN triode T2Base stage connection,
NPN triode T2Collector and diode D3Cathode connection, diode D3Anode and full-wave rectification bridge end four connect,
NPN triode T2Emitter be used for and load connect；
The equivalent internal resistance and equivalent capacity for enabling piezoelectric energy collector constant voltage source model are expressed as Rs、Cj, capacitor CHPWith
Resistance RHPCapacitance and resistance value be expressed as CHPAnd RHP, storage capacitor CiCapacitance be expressed as Ci, then R is enableds、Cj、CHP、RHPWith
CiMeet condition:
Compared with prior art, the beneficial effects of the present invention are:
The circuit control module provided by the invention for extracting circuit is made of discrete analog circuit device, uses two three
Pole pipe serves as the role of comparator and switch, can successfully capture maximum power point and complete the collection of piezoelectric energy, and
And without additional devices such as programmable controllers.Therefore, which has low-power consumption, and impedance is independent, self-starting, nothing
The advantages that needing battery.
Detailed description of the invention
Fig. 1 is the structural schematic diagram for extracting circuit.
Fig. 2 is the equivalent circuit of piezoelectric energy collector, full-wave rectification bridge, storage capacitor and passive high three-way filter
Figure.
Fig. 3 is storage capacitor CiWith resistance RHPVoltage curve.
Fig. 4 is the circuit diagram for extracting the charging stage of circuit.
Fig. 5 is the circuit diagram for extracting circuit maximum power point acquisition phase.
Fig. 6 is the circuit diagram for extracting the Energy extraction stage of circuit.
Specific embodiment
The attached figures are only used for illustrative purposes and cannot be understood as limitating the patent；
Below in conjunction with drawings and examples, the present invention is further elaborated.
Embodiment 1
As shown in Figure 1, the self-powered piezoelectric vibration energy that can track maximum power point provided by the invention extracts electricity
Road, including piezoelectric energy collector, full-wave rectification bridge, storage capacitor Ci, passive high three-way filter and circuit control module.This reality
It applies in example, piezoelectric energy collector is piezoelectric patches.
Wherein the positive output end of piezoelectric energy collector, negative output terminal be in respectively with full-wave rectification bridge diagonal end one,
Two connection of end, the end three of full-wave rectification bridge are grounded, the end four of full-wave rectification bridge and storage capacitor CiAnode connection, storage capacitor
CiCathode ground connection；
Passive high three-way filter includes capacitor CHPWith resistance RHP, capacitor CHPAnode connect with the end four of full-wave rectification bridge,
Capacitor CHPCathode pass through resistance RHPGround connection；
The circuit control module includes resistance R1, diode DHP, diode D1, capacitor C1, resistance R2, resistance R3, two poles
Pipe D2, PNP triode T1, diode D3With NPN triode T2；Wherein diode DHPCathode and capacitor CHPCathode connection, two
Pole pipe DHPPlus earth；Resistance R1One end and capacitor CHPCathode connection, resistance R1The other end and diode D1Sun
Pole connection, diode D1Cathode and capacitor C1Anode connection, capacitor C1Cathode ground connection；The PNP triode T1Transmitting
Pole and diode D2Cathode connection, diode D2Anode and capacitor C1Anode connection；PNP triode T1Base stage pass through
Resistance R2With capacitor CHPCathode connection, PNP triode T1Collector pass through resistance R3With NPN triode T2Base stage connection,
NPN triode T2Collector and diode D3Cathode connection, diode D3Anode and full-wave rectification bridge end four connect,
NPN triode T2Emitter be used for and load connect；
The equivalent internal resistance and equivalent capacity for enabling piezoelectric energy collector constant voltage source model are expressed as Rs、Cj, capacitor CHPWith
Resistance RHPCapacitance and resistance value be expressed as CHPAnd RHP, storage capacitor CiCapacitance be expressed as Ci, then R is enableds、Cj、CHP、RHPWith
CiMeet condition:
Shown in institute Fig. 2, which is piezoelectric energy collector, full-wave rectification bridge, storage capacitor and passive high-pass filtering
The constant voltage equivalent circuit of device.Resistance RsFor the internal resistance of piezoelectric energy collector, passive high three-way filter time constant is equal to pressure
The half of time constant in electric flux collector, i.e.,Resistance RHPVoltage and storage capacitor
CiVoltage curve be Fig. 3, as time t=τ ln 2, resistance RHPVoltage reach peak valueLucky storage capacitor CiVoltage
Also reach open-circuit voltage VOCHalf, be the corresponding voltage value of maximum power point.
As shown in figure 4, Fig. 4 is the circuit diagram for extracting the charging stage of circuit.Piezoelectric energy collector generates alternating current,
To be continuously the storage capacitor C that original state is zeroiIt charges, while the resistance R of passive high three-way filterHPOn voltage
Also it begins to ramp up, the C in circuit control module1Also start energy storage, due to triode T1Upper emitter to the voltage between base stage not
Have and is greater than emitter junction conducting voltage, therefore triode T1In not turning on state.
As shown in figure 5, Fig. 5 is the circuit diagram for extracting circuit maximum power point acquisition phase.As storage capacitor CiOn electricity
Pressure is charged to justWhen, the resistance R of positive value passive high three-way filterHPOn voltage reach maximum value, i.e. its voltage waveform
Then peak value is begun to decline.Due to diode D2With triode T1Effect, as resistance RHPOn voltage decline 2VD+VBEWhen,
Triode T1Upper emitter starts to be greater than emitter junction conducting voltage to the voltage between base stage, to promote triode T1Access switch
On state.Capacitor C1Start to discharge, with diode D2, triode T1The end ec, resistance R3, triode T2The end be formed back
Road promotes triode T2Into saturation state, it is equivalent to switch conduction.Due to voltage 2VD+VBEIt is minimum, resistance RHPOn voltage
Decline 2VD+VBERequired time is extremely short, for the vibration period, can be ignored, therefore, resistance RHPUpper voltage waveform
Peak value can be detected, i.e. the maximum power point of piezoelectric energy collector is successfully captured to.
As shown in fig. 6, Fig. 6 is the circuit diagram for extracting the Energy extraction stage of circuit.Triode T2In maximum power point
It is activated at quarter on state, storage capacitor CiOn charge can be transferred to application load, and then complete to piezoelectricity energy
The extraction of amount.Capacitor C on passive high three-way filterHPEnergy pass through sustained diodeHPIt is transferred to application load.
In conclusion circuit of the invention uses well-designed passive high three-way filter, realize to piezoelectricity maximum work
The tracking of rate point is captured as control module with simple topological circuit using discrete component, realizes and answer for burst type
It is powered with load, so as to complete the design of self-powered maximum power point energy collection circuit.The circuit is supplied without external
Electricity is not needed using complicated integrated chip, and there are no the auxiliary for needing the additional processors such as DSP or microprocessor.Due to control
The lower and whole circuit of the power consumption of circuit is simpler, moreover, application load and integrated circuit keep independent, is independent of each other, because
This, which has the advantages that high efficiency, design is simple, complete self-powered, loaded self-adaptive.
Obviously, the above embodiment of the present invention be only to clearly illustrate example of the present invention, and not be pair
The restriction of embodiments of the present invention.For those of ordinary skill in the art, may be used also on the basis of the above description
To make other variations or changes in different ways.There is no necessity and possibility to exhaust all the enbodiments.It is all this
Made any modifications, equivalent replacements, and improvements etc., should be included in the claims in the present invention within the spirit and principle of invention
Protection scope within.
Claims (2)
1. the self-powered piezoelectric vibration energy that can track maximum power point extracts circuit, it is characterised in that: including piezoelectricity energy
Measure collector, full-wave rectification bridge, storage capacitor Ci, passive high three-way filter and circuit control module；
Wherein the positive output end of piezoelectric energy collector, negative output terminal are in diagonal end one, end two with full-wave rectification bridge respectively
The end three of connection, full-wave rectification bridge is grounded, the end four of full-wave rectification bridge and storage capacitor CiAnode connection, storage capacitor Ci's
Cathode ground connection；
Passive high three-way filter includes capacitor CHPWith resistance RHP, capacitor CHPAnode connect with the end four of full-wave rectification bridge, capacitor
CHPCathode pass through resistance RHPGround connection；
The circuit control module includes resistance R1, diode DHP, diode D1, capacitor C1, resistance R2, resistance R3, diode D2、
PNP triode T1, diode D3With NPN triode T2；Wherein diode DHPCathode and capacitor CHPCathode connection, diode
DHPPlus earth；Resistance R1One end and capacitor CHPCathode connection, resistance R1The other end and diode D1Anode connect
It connects, diode D1Cathode and capacitor C1Anode connection, capacitor C1Cathode ground connection；The PNP triode T1Emitter with
Diode D2Cathode connection, diode D2Anode and capacitor C1Anode connection；PNP triode T1Base stage pass through resistance R2
With capacitor CHPCathode connection, PNP triode T1Collector pass through resistance R3With NPN triode T2Base stage connection, NPN tri-
Pole pipe T2Collector and diode D3Cathode connection, diode D3Anode and full-wave rectification bridge end four connect, NPN tri-
Pole pipe T2Emitter be used for and load connect；
The equivalent internal resistance and equivalent capacity for enabling piezoelectric energy collector constant voltage source model are expressed as Rs、Cj, capacitor CHPAnd resistance
RHPCapacitance and resistance value be expressed as CHPAnd RHP, storage capacitor CiCapacitance be expressed as Ci, then R is enableds、Cj、CHP、RHPAnd CiIt is full
Sufficient condition:
2. the piezoelectric vibration energy that can track maximum power point of power supply according to claim 1 extracts circuit, special
Sign is: the piezoelectric energy collector is piezoelectric patches.
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Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108390448A (en) * | 2018-01-31 | 2018-08-10 | 浙江大学宁波理工学院 | Piezoelectricity energy-collecting device |
| DE102018201925A1 (en) * | 2018-02-07 | 2019-08-08 | Würth Elektronik eiSos Gmbh & Co. KG | Apparatus for obtaining electrical energy and energy producers with such a device |
| CN108365774B (en) * | 2018-03-23 | 2019-09-10 | 佛山市顺德区中山大学研究院 | A kind of novel vibrating energy acquisition circuit |
| CN108809145B (en) * | 2018-04-24 | 2019-12-13 | 西安电子科技大学 | Maximum power point tracking control piezoelectric energy acquisition circuit |
| CN108900113B (en) * | 2018-06-19 | 2019-06-07 | 大连理工大学 | A kind of synchronous charge-extraction of efficiently self-powered piezoelectricity and voltage reverse circuit |
| CN109004862A (en) * | 2018-08-02 | 2018-12-14 | 湖南工业大学 | A kind of low latency self-powered piezo-electric generating synchronization charge-extraction circuit |
| CN110752744B (en) * | 2019-10-29 | 2020-09-11 | 合肥工业大学 | Non-inductance self-starting energy collection system for piezoelectric energy collection |
| CN112491295B (en) * | 2020-11-20 | 2024-06-25 | 宁波大学 | Piezoelectric energy collection circuit based on maximum power point tracking |
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| JPH03285403A (en) * | 1990-03-31 | 1991-12-16 | Kinseki Ltd | Piezoelectric oscillation circuit |
| CN102938621A (en) * | 2011-08-15 | 2013-02-20 | 朴昌浩 | Vibration energy collecting system |
| EP2764372B1 (en) * | 2011-10-07 | 2018-08-15 | Fraunhofer Gesellschaft zur Förderung der angewandten Forschung e.V. | Peak detector with false peak rejection |
| CN105553330B (en) * | 2015-12-08 | 2017-12-26 | 广东顺德中山大学卡内基梅隆大学国际联合研究院 | Non-linear piezoelectric energy recovery interface circuit inductor design and method of controlling switch |
| CN205610495U (en) * | 2016-04-18 | 2016-09-28 | 四川建筑职业技术学院 | Passive piezoelectricity vibration generator interface circuit |
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