CN108649837B - A piezoelectric energy storage device for oil well downhole detection equipment - Google Patents
A piezoelectric energy storage device for oil well downhole detection equipment Download PDFInfo
- Publication number
- CN108649837B CN108649837B CN201810598238.7A CN201810598238A CN108649837B CN 108649837 B CN108649837 B CN 108649837B CN 201810598238 A CN201810598238 A CN 201810598238A CN 108649837 B CN108649837 B CN 108649837B
- Authority
- CN
- China
- Prior art keywords
- piezoelectric
- cantilever beam
- circuit
- beam base
- piezoelectric ceramic
- Prior art date
- 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.)
- Active
Links
Images
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
- H02N2/185—Electric machines in general using piezoelectric effect, electrostriction or magnetostriction producing electrical output from mechanical input, e.g. generators using fluid streams
Landscapes
- Geophysics And Detection Of Objects (AREA)
Abstract
本发明公开了一种用于油井井下检测设备的压电储能装置。圆柱形主体的上下端设置有螺纹丝扣，螺纹丝扣与抽油杆柱相连，悬臂梁基体在圆柱形主体的圆周上并列设置有多排，悬臂梁基体上下侧均通过导电胶粘贴有压电陶瓷片，悬臂梁基体末端设置有质量块，质量块与抽油杆之间均不接触，圆柱形主体外部还设置有保护罩，电路板设置在圆柱形主体中部，压电陶瓷片产生的不稳定电流经过增压电路、整流电路和负载匹配电路，得到稳定直流电储存起来，以供负载使用。本发明结构简单，能够将在抽油过程中利用井下流体的振动冲击产生的能量转换为可利用的电能，并将电能储存到可充电电池中，供井下检测设备使用。
The invention discloses a piezoelectric energy storage device used for downhole detection equipment of oil wells. The upper and lower ends of the cylindrical body are provided with threaded screws, which are connected to the sucker rod column, the cantilever beam base is arranged in multiple rows on the circumference of the cylindrical body, and the upper and lower sides of the cantilever beam base are pasted with conductive glue. Piezoelectric ceramic sheet, a mass block is arranged at the end of the base body of the cantilever beam, and the mass block and the sucker rod are not in contact with each other. The unstable current passes through the booster circuit, the rectifier circuit and the load matching circuit to obtain stable DC power and store it for the load. The invention has a simple structure, and can convert the energy generated by the vibration and impact of the downhole fluid in the oil pumping process into usable electric energy, and store the electric energy in a rechargeable battery for use by the downhole detection equipment.
Description
Technical Field
The invention relates to the combination of the research field of mechanical oil extraction engineering and the technical field of electricity, in particular to a piezoelectric energy storage device which obtains energy from the underground liquid vibration of an oil well and converts and stores the energy into the piezoelectric energy storage device, is suitable for the occasions of obtaining energy from the vibration environment and converting and applying, and particularly relates to a piezoelectric energy storage device for underground detection equipment of the oil well.
Background
Mechanical oil extraction is a main oil extraction mode of oil fields at home and abroad, and efficient operation of underground equipment is a key influencing efficiency of a mechanical oil extraction system, so that the operation state of the underground equipment is effectively monitored, and real-time adjustment of oil extraction parameters is the core of oil field management, but popularization and application of the underground oil-water well monitoring equipment are always difficult problems, for example, an underground dynamometer for monitoring the operation state of an oil-well pump, an intelligent water distributor for monitoring and adjusting injection quantity of a water injection layer and the like, the equipment needs continuous power supply, and due to limitation of a shaft space, continuous power supply under the shaft is difficult, so that the application of the underground monitoring equipment is still in a test research stage.
Mechanical oil recovery mainly utilizes oil recovery equipment in the pit to lift liquid in the pit to ground, and oil recovery equipment's theory of operation in the pit mainly relies on the pump barrel internal pressure change to realize the suction of liquid, and well liquid vibrates under the pressure effect, so utilizes the vibration energy of liquid, through enlargeing the principle, turns into the vibration energy electric energy to the storage, and as monitoring facilities's supply power in the pit, can effectually solve the power supply problem of equipment in the pit, provides probably for the application of development intelligent underground equipment simultaneously.
Since the curie brother in the 80 th 19 th century discovered the piezoelectric effect on quartz crystal, the study of piezoelectric materials and piezoelectric elements has attracted attention from domestic and foreign researchers, and piezoelectric materials and devices for recovering and utilizing vibration energy in the environment have been developed in recent years. At present, lead zirconate titanate is the most commonly used piezoelectric material, LEE research shows that piezoelectric ceramics are very susceptible to fatigue cracking and brittle fracture under high frequency periodic load, polyvinylidene fluoride is suitable for high frequency periodic vibration load [ LEE C S, JOO J, HAN S, et al.Multifuntional transducer using poly (3,4-ethylenedioxythiophene) electrode: active and generator [ J ] Applied Physics letters, 2004,85(10):1841 1844 ], Adrien Bade research shows that under the same conditions, the recovery energy of single crystal is more than 20 times higher than that of piezoelectric ceramics [ YADEL A, BED A, LERE, silicon, crystal ] and piezoelectric ceramics [ FC ] 6753, IEEE 6753. piezoelectric ceramics J ] research, ng and Liao research shows that the single crystal wafer is suitable for occasions with lower vibration force and lower frequency, the parallel piezoelectric bimorph is suitable for occasions with higher vibration force and higher vibration frequency [ NG T H, LIAO W H. sensing analysis and energy harving for a selected-powered piezoelectric sensor [ J ]. Journal of organic Material Systems and Structures,2005,16(10): 785. 797 ], Jun wushu establishes simulation analysis of power generation capability of the single-crystal and double-crystal piezoelectric beams, optimizes the matching relation between mechanical properties and dimensions of materials [ JJJJJJJJJJJJJJJJU, JUNGU JUN, JUNGU, JUNHUN, etc.. piezoelectric cantilever beam power generation device and simulation analysis [ J ]. rectangle optical engineering, 2008,16(1):1-76 ], MotaoU energy recovery effect, MotaO unit area and sensitivity of piezoelectric cantilever beam power generation device, the triangular piezoelectric cantilever beam has better energy recovery rate [ MATEU L, MOLL F.Optimum piezoelectric bonding beam structures for energy transforming use shell inserts [ J ]. Intell Mater Syst Structure, 2005,16:835-845 ]. A piezoelectric mini windmill was invented by Priya in terms of piezoelectric energy recovery [ PRIYA S.Modulatoring of electric energy harnessing using Applied Physics Letter,2005,87(18):4101 ], Dongna prepared a piezoelectric cantilever beam for MEMS power supply [ SHEN Dongcna, PARK Junggyun, NOH J H, et al, Micromachined cantilever base on strained SOI structure for frequency vibration energy harnessing [ J ] Sensors and Actuators A: Physics, 2009(154): 103-. The vibration energy recovery based on the piezoelectric material is a new technology, and can provide powerful technical support for remote monitoring equipment without battery and manpower maintenance in the future.
In conclusion, the invention designs the piezoelectric energy storage device for the oil well underground detection equipment.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a piezoelectric energy storage device for oil well underground detection equipment, which has a simple structure, can convert energy generated by vibration impact of underground fluid in the oil pumping process into usable electric energy, and stores the electric energy into a rechargeable battery for the underground detection equipment.
In order to achieve the purpose, the invention is realized by the following technical scheme: a piezoelectric energy storage device for oil well underground detection equipment comprises a cantilever beam base body, piezoelectric ceramic pieces, a mass block, a protective cover, a plurality of rows of thread screws and a circuit board, wherein the upper end and the lower end of a cylindrical main body are provided with the thread screws, the thread screws are connected with a sucker rod column, the cantilever beam base body is arranged on the circumference of the cylindrical main body in parallel, the upper side and the lower side of the cantilever beam base body are respectively pasted with the piezoelectric ceramic pieces through conductive adhesives, the tail end of the cantilever beam base body is provided with the mass block, the mass block is not contacted with the sucker rod, the protective cover is also arranged outside the cylindrical main body, the circuit board is arranged in the middle of the cylindrical main body, the circuit board comprises a booster circuit, a rectifier circuit and a load matching circuit, the booster circuit, the rectifier circuit and the load, the stable direct current is stored for use by a load.
Preferably, the mass blocks are concentric curved surfaces on the same circumference and are in clearance fit with the sucker rod, the distance between the mass blocks among different layers is delta, and the distance is determined by the amplitude of the liquid excitation mass block.
Preferably, the voltage boosting circuit adopts a parallel SSHI interface, consists of an inductor and a switch which are connected in series, and is used for boosting the voltage of the piezoelectric sheet.
Preferably, the rectifier circuit adopts a rectifier bridge, and converts alternating current voltage generated by the piezoelectric recovery device under vibration into unidirectional pulsating direct current by utilizing unidirectional conductivity of a semiconductor diode.
Preferably, the load matching circuit can automatically adjust the rectified voltage according to the amplitude of vibration, so that the pulsating direct current tends to be stable, and the purpose of storing electric quantity is achieved by adopting a mode that a capacitor is connected with the load in parallel.
The invention provides the piezoelectric storage device for the oil well underground detection equipment, which has the following application: by utilizing the piezoelectric effect of the piezoelectric ceramic, in the process of up-and-down movement of the sucker rod, the impact vibration of underground fluid acts on the piezoelectric vibrator through the mass block to generate electric charge, and the obtained electric energy is used for underground detection equipment through the load matching circuit.
The invention has the following beneficial effects:
1. the piezoelectric vibrator matrix is clamped in a cantilever beam mode, bending deformation is mainly concentrated on the middle part, and a mass block is clamped at the tail end of the piezoelectric matrix to increase the bending deformation; the piezoelectric vibrators are connected in parallel, so that the energy output of the piezoelectric energy storage device is increased.
2. The upper and lower ceramic plates of each piezoelectric vibrator matrix are connected in series, positive charges are concentrated on the upper polar plate, negative charges are concentrated on the lower polar plate, and negative charges generated on the middle polar plate are offset with positive charges generated on the lower polar plate; the total charge output is equal to the monolithic charge and the output voltage is twice the monolithic voltage, the total capacitance being half that of the monolithic capacitance.
3. The piezoelectric vibrators are connected in parallel, and the overall output energy of the piezoelectric energy storage device is increased.
4. The circuit is small in size and low in cost;
5. the whole set of piezoelectric energy storage device has simple structure: the piezoelectric vibrator comprises a piezoelectric vibrator base body, a circuit driving part and a piezoelectric vibrator base body, wherein the piezoelectric vibrator base body is used for generating electricity; the connection between each part is simple.
6. The application is wide: all underground devices can utilize weak mechanical energy and convert the weak mechanical energy into electric energy for application of underground detection equipment.
Drawings
The invention is described in detail below with reference to the drawings and the detailed description;
FIG. 1 is a schematic plan view of the present invention;
FIG. 2 is a schematic diagram of the operation of the piezoelectric vibrator in horizontal circumferential arrangement according to the present invention;
fig. 3 is a schematic structural view of a monolithic piezoelectric vibrator of the present invention;
FIG. 4 is a schematic circuit diagram of the circuit board of the present invention;
fig. 5 is a schematic perspective view of the present invention.
Detailed Description
In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.
Referring to fig. 1 to 5, the following technical solutions are adopted in the present embodiment: a piezoelectric energy storage device for oil well underground detection equipment comprises a cantilever beam substrate 1, piezoelectric ceramic pieces 2, a mass block 3, a protective cover 4, thread screws 5 and a circuit board 6, wherein the upper end and the lower end of a cylindrical main body 7 are provided with the thread screws 5, the thread screws 5 are connected with a sucker rod column, the cantilever beam substrate 1 is provided with a plurality of rows on the circumference of the cylindrical main body 7 in parallel, the piezoelectric ceramic pieces 2 are adhered to the upper side and the lower side of the cantilever beam substrate 1 through conductive adhesives, the mass block 3 is arranged at the tail end of the cantilever beam substrate 1, the mass block 3 is not in contact with the sucker rod, the protective cover 4 is also arranged outside the cylindrical main body 7, the circuit board 6 is arranged in the middle of the; the circuit board 6 comprises a booster circuit, a rectifier circuit and a load matching circuit, the booster circuit, the rectifier circuit and the load matching circuit are all driven in a voltage stabilization mode, and unstable current generated by the piezoelectric ceramic piece 2 passes through the booster circuit, the rectifier circuit and the load matching circuit to obtain stable direct current and store the stable direct current for a load to use.
The piezoelectric energy storage device of the embodiment adopts a working mode that a plurality of piezoelectric ceramic piece cantilever beams are arranged side by side in the horizontal direction, and the vibration of the device is completed by a cantilever beam substrate and the piezoelectric ceramic pieces stuck on the cantilever beam substrate; and the vibration between the cantilever beam matrixes is synchronous, and the cantilever beam matrixes use one mass block 3 independently.
The mass block 3 of the present embodiment mainly accomplishes capturing vibration and increasing the strain amplitude of the piezoelectric ceramic sheet. The upper piezoelectric ceramic piece and the lower piezoelectric ceramic piece of the cantilever beam substrate 1 are connected in series, the cantilever beam substrate and the upper piezoelectric ceramic piece and the lower piezoelectric ceramic piece form a piezoelectric vibrator, and the piezoelectric vibrators are connected in parallel. Wherein each mass block weighs 6-8 g.
The cantilever beam base bodies 1 are made of beryllium bronze, base bodies with the thickness of 25 multiplied by 8 and the thickness of 0.3mm are adopted, one end of each cantilever beam base body 1 is clamped by a fixed end, and the other end of each cantilever beam base body is a moving end and is clamped by a mass block. The moving direction of the moving end is the height direction of the cantilever beam base body 1.
The piezoelectric ceramic pieces 2 are positioned on the upper side and the lower side of the cantilever beam substrate 1, and the piezoelectric ceramic pieces 2 are adhered to the cantilever beam substrate 1 through conductive adhesives and used for converting weak mechanical energy in the environment into electric energy.
The piezoelectric ceramic piece 2 is made of PTZ-5H piezoelectric material with the thickness of 20 multiplied by 8 and the thickness of 0.2mm, and the piezoelectric ceramic piece 2 is adhered to the piezoelectric vibrator base body 1 by conductive adhesive. Before pasting, the surface of the piezoelectric vibrator base body needs to be cleaned by alcohol, and no foreign matters are kept on the surface of the piezoelectric vibrator base body. The thickness of the conductive paste should be kept within 0.1 mm. And positive and negative electrodes are led out from the upper and lower parts of the piezoelectric ceramic 2.
The piezoelectric energy storage device has a structure shown in fig. 4, and comprises a voltage reduction circuit, a rectifying circuit and an electricity storage circuit, wherein the functions of the voltage reduction circuit, the rectifying circuit and the electricity storage circuit are that electric energy is extracted, and power is adjusted to be used or stored by oil well underground detection equipment. The piezoelectric energy storage device is installed on the sucker rod.
The voltage reduction capacitor of the voltage reduction circuit is determined by that C is larger than or equal to I/2 pi fU, wherein I is load current, U is load voltage, F is the average frequency of generated electricity, 50HZ is obtained, C is 17 mu F, and the voltage reduction capacitor is used for limiting the voltage in the working range of the load.
The rectifier circuit adopts a full-wave bridge rectification mode, and a rectifier bridge is formed by 4 commonly used rectifier diodes IN4001(U is 50V, and I is 1A), so that alternating current generated by the piezoelectric vibrator ceramic piece 2 is converted into unidirectional pulse direct current.
The storage circuit (DC-DC circuit) is connected in parallel by a capacitor and a resistor. The charge generated by the downhole power generation equipment is collected.
The LED lamp bead is welded on the circuit board.
Acceleration of downhole fluid of 0.64m/s2(ii) a The mass of downhole fluid is 68 Kg; the force generated by the vibration of the downhole fluid is F0＝ma＝68×0.64＝43.52N。
The pumping frequency of the pumping rod is 6 times per minute, and the time for completing one-time up stroke is 5 s;
according to fluid mechanics FR＝ρgycS＝1000×9.8×4×0.017＝666.4N.
The logic calculation method for obtaining energy by the power generation device comprises the following steps: wherein the external electric field is 0, and the time of the external force acting alone can be represented by the formula
Calculating the generated charge amount; according to the free capacitance of the piezoelectric vibrator
And obtaining the piezoelectric vibrator open circuit voltage according to the relation Q ═ CV between the charge and the voltage
According to the electric energy calculation formula Ug＝QgVgAnd/2, obtained by obtaining the piezoelectric energy storage device
The working process of the specific embodiment is as follows: the mass block transfers the vibration of underground fluid, the vibration is transferred to the piezoelectric ceramic piece, the piezoelectric vibrator taking the cantilever beam as a clamping form deforms under the action of force, so that the piezoelectric ceramic piece generates electric charge, the generated electric charge flows out through two electrodes in the middle of the ceramic piece, and the electric energy is adjusted to be used by underground detection equipment through the arrangement of the control circuit.
The piezoelectric energy storage device for the downhole detection equipment of the specific embodiment comprises: through installing piezoelectricity energy memory on sucker rod in the pit, let faint vibration energy conversion for usable electric energy to in storing the check out test set with the electric energy, by less the collection many, finally reach energy-conserving effect.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (2)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810598238.7A CN108649837B (en) | 2018-06-12 | 2018-06-12 | A piezoelectric energy storage device for oil well downhole detection equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810598238.7A CN108649837B (en) | 2018-06-12 | 2018-06-12 | A piezoelectric energy storage device for oil well downhole detection equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108649837A CN108649837A (en) | 2018-10-12 |
| CN108649837B true CN108649837B (en) | 2021-03-02 |
Family
ID=63752368
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810598238.7A Active CN108649837B (en) | 2018-06-12 | 2018-06-12 | A piezoelectric energy storage device for oil well downhole detection equipment |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108649837B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US12126281B2 (en) | 2022-09-27 | 2024-10-22 | Cairdac | Pendular unit with an inertial mass mounted on a piezoelectric beam, in particular for an energy harvester in a leadless autonomous cardiac capsule |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109763792A (en) * | 2019-02-27 | 2019-05-17 | 中国地质大学（武汉） | A type of vibration energy harvester while drilling |
| CN112284355B (en) * | 2020-09-14 | 2022-07-26 | 北京致感致联科技有限公司 | Passive piezoelectric sensor and monitoring system |
| CN114094873B (en) * | 2021-11-18 | 2022-11-25 | 武汉市市政建设集团有限公司 | Device for realizing self-power supply of bridge structure monitoring equipment |
| CN114831381B (en) * | 2022-06-09 | 2024-06-25 | 广州大学 | Piezoelectric sensing power generation device and self-generating sports shoes |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103746603A (en) * | 2014-01-17 | 2014-04-23 | 哈尔滨工程大学 | Photonic crystal power generating device based on longitudinal vibration band gap |
| CN105006991A (en) * | 2015-07-22 | 2015-10-28 | 上海交通大学 | Laminated piezoelectric downhole energy collection device |
| CN103762892B (en) * | 2014-01-17 | 2016-01-27 | 哈尔滨工程大学 | A kind of phonon crystal Blast Furnace Top Gas Recovery Turbine Unit (TRT) based on torsional oscillation band gap |
| CN105915110A (en) * | 2016-05-04 | 2016-08-31 | 中国石油大学(华东) | Downhole vibration energy collection device |
| CN206922664U (en) * | 2017-06-15 | 2018-01-23 | 长春吉威新能源科技发展有限公司 | A kind of magnetic suspension vibrating prisoner can battery |
-
2018
- 2018-06-12 CN CN201810598238.7A patent/CN108649837B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103746603A (en) * | 2014-01-17 | 2014-04-23 | 哈尔滨工程大学 | Photonic crystal power generating device based on longitudinal vibration band gap |
| CN103762892B (en) * | 2014-01-17 | 2016-01-27 | 哈尔滨工程大学 | A kind of phonon crystal Blast Furnace Top Gas Recovery Turbine Unit (TRT) based on torsional oscillation band gap |
| CN105006991A (en) * | 2015-07-22 | 2015-10-28 | 上海交通大学 | Laminated piezoelectric downhole energy collection device |
| CN105915110A (en) * | 2016-05-04 | 2016-08-31 | 中国石油大学(华东) | Downhole vibration energy collection device |
| CN206922664U (en) * | 2017-06-15 | 2018-01-23 | 长春吉威新能源科技发展有限公司 | A kind of magnetic suspension vibrating prisoner can battery |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US12126281B2 (en) | 2022-09-27 | 2024-10-22 | Cairdac | Pendular unit with an inertial mass mounted on a piezoelectric beam, in particular for an energy harvester in a leadless autonomous cardiac capsule |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108649837A (en) | 2018-10-12 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108649837B (en) | A piezoelectric energy storage device for oil well downhole detection equipment | |
| Priya et al. | Piezoelectric windmill: A novel solution to remote sensing | |
| CN101359882B (en) | Piezoelectric vibration energy collecting apparatus with adjustable resonance frequency | |
| Kim et al. | A review of piezoelectric energy harvesting based on vibration | |
| Kumar et al. | Piezoelectric energy harvester design and power conditioning | |
| CN101295941B (en) | AC nano generator | |
| CN203654673U (en) | Piezoelectric power-generating floor | |
| CN101262189A (en) | Piezoelectric Generator Harvesting Bending Vibration Energy | |
| CN109768736A (en) | A passive detection device and method for pipeline liquid flow | |
| CN110572076B (en) | Multi-direction piezoelectric vibration energy collecting device | |
| CN102570620B (en) | Walking energy collection system | |
| CN108347196B (en) | A Vibration Energy Harvesting System Based on Magnetoelectric Composite Materials | |
| CN101106301A (en) | Vibrating electrostatic micro-generator and its array based on liquid medium | |
| CN111884541B (en) | A piezoelectric energy harvesting device and method thereof | |
| CN108199617B (en) | A kind of transverse direction MEMS piezoelectricity-electrostatic coupling energy collecting device and processing method | |
| CN112187097A (en) | Symmetrical structure vibration energy collecting device | |
| CN106793287A (en) | A kind of LED illumination circuit generated electricity based on human pressure | |
| CN210075112U (en) | A layered magnetoelectric composite energy harvester | |
| Samal et al. | Energy harvesting using piezoelectric transducers: a review | |
| CN205725110U (en) | New piezoelectric underwater vibration energy harvesting device | |
| CN202721628U (en) | High-power Rotary Piezoelectric Wind Power Generator Excited and Limited by End Cam | |
| JPH1118445A (en) | Piezoelectric type generator and manufacture thereof | |
| CN203119792U (en) | Piezoelectric energy harvesting unit | |
| CN111424722A (en) | A passive intelligent manhole cover system based on piezoelectric ceramics and its working method | |
| JP5979353B2 (en) | Power generation device, electronic device, moving means and battery |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |