Vibration energy collecting device
By introducing a buffer unit to adaptively adjusting the vibration frequency in the vibration energy harvesting device, the problem of low power collection efficiency caused by mismatch in the vibration frequency in the prior art is solved, and efficient power conversion at different driving speeds is achieved.
Patent Information
- Application Number
- CN202411350307.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-26
- Publication Date
- 2024-12-13
AI Technical Summary
Existing vibration energy harvesting devices can only efficiently collect electrical energy at specific frequencies, and it is difficult to efficiently collect electrical energy under vibration frequency conditions at different vehicle driving speeds.
A vibration energy harvesting device including an energy conversion unit and a buffer unit is designed. The vibration frequency of the energy conversion unit is adaptively adjusted by the buffer unit to coordinate with the vibration frequency of the vibration source, thereby improving energy collection at different vibration frequencies. efficiency.
The maximum vibration energy collection efficiency and conversion of electric energy under different vibration frequency conditions is achieved, ensuring the efficient operation of the vibration energy collection device at different driving speeds.
Smart Images
Figure CN119134961A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present invention relate to the field of energy collection, and in particular to a vibration energy collection device. Background Art
[0002] Environmental energy harvesting technology is a technology that uses energy harvesting devices to convert the widely existing energy in the natural environment, such as solar energy, wind energy, tidal energy, vibration energy, etc., into electrical energy for storage and use. Vibration energy is a type of energy that is widely present in life and engineering. For example, a vehicle will vibrate during driving. If this vibration energy is collected and used to power the sensor, it can be driven to monitor the system status.
[0003] The vibration energy harvesting device of the prior art can only collect electrical energy at a high power when vibrating at a specific frequency. If it deviates from this frequency, the efficiency of energy collection by the vibration energy harvesting device will be greatly reduced. However, the driving speed of a vehicle is usually not fixed. The vibration frequency generated by the vehicle is different when the vehicle is driving at a low speed and when it is driving at a high speed. Therefore, it is difficult for the traditional vibration energy harvesting device to efficiently collect electrical energy under the vibration conditions of different vehicle driving speeds. Summary of the invention
[0004] The embodiment of the present invention provides a vibration energy collection device, which can collect vibration energy with high efficiency.
[0005] According to one aspect of the present invention, there is provided a vibration energy harvesting device, comprising:
[0006] an energy conversion unit, one end of which is fixed to an external vibration source to convert the mechanical vibration energy of the vibration source into electrical energy;
[0007] A buffer unit, the other end of the energy conversion unit is coupled to an external vibration source through the buffer unit, and the buffer unit is used to adaptively adjust the vibration frequency of the energy conversion unit.
[0008] Optionally, the energy conversion unit includes a vibration beam and a mass block, the extension direction of the vibration beam is perpendicular to the vibration direction of the vibration source, one end of the vibration beam is connected to the vibration source, and the other end of the vibration beam is fixed to the mass block.
[0009] Optionally, the buffer unit includes a first buffer and a second buffer, the first buffer is fixed to the vibration source, and the second buffer is fixed to a side of the mass block or the vibration beam facing the first buffer.
[0010] Optionally, the vibration energy collection device further includes a buffer control unit, which is used to adjust the electrostatic force between the first buffer member and the second buffer member to increase the energy conversion efficiency of the energy conversion unit.
[0011] Optionally, the first buffer component and the second buffer component include electrode plates arranged opposite to each other, and the buffer control unit is used to adjust the voltage difference between the first buffer component and the second buffer component.
[0012] Optionally, the buffer control unit includes:
[0013] The voltage conversion unit is used to convert the first voltage generated by the energy conversion unit into a second voltage.
[0014] The voltage detection unit is used to detect the second voltage output by the voltage conversion unit.
[0015] The efficiency judgment unit is used to determine the change amount of the conversion efficiency of the energy conversion unit according to the change of the second voltage;
[0016] The buffer control unit is used to continuously increase or decrease the voltage difference between the first buffer component and the second buffer component when the conversion efficiency of the energy conversion unit decreases, so as to increase the conversion efficiency of the energy conversion unit to near a maximum value.
[0017] Optionally, the first buffer component and the second buffer component are electrode arrays arranged opposite to each other, and the buffer control unit is used to select a preset number and / or position of electrode pairs to generate electrostatic force, and no electrostatic force is generated between other electrode pairs.
[0018] Optionally, the buffer control unit includes:
[0019] A voltage detection unit, used to detect the voltage value output by the energy conversion unit;
[0020] an efficiency determination unit, configured to determine a second change in the conversion efficiency of the energy conversion unit according to a first change in the voltage value output by the energy conversion unit within a preset time;
[0021] A buffer control unit is used to continuously increase or decrease the number of electrode pairs that generate electrostatic force when the conversion efficiency of the energy conversion unit decreases, so as to increase the conversion efficiency; and / or continuously increase or decrease the voltage difference between each pair of first electrodes and second electrodes, so as to increase the conversion efficiency of the energy conversion unit to near a maximum value.
[0022] Optionally, the vibration source includes a first surface and a second surface adjacent to each other, one end of the vibration beam is connected to the first surface, and the first buffer is fixed to the second surface.
[0023] Optionally, the vibration beam further includes an elastic rod and a piezoelectric converter fixed integrally with the elastic rod, and when the elastic rod vibrates and bends, the piezoelectric converter is repeatedly deformed to convert mechanical vibration energy into electrical energy.
[0024] Compared with the prior art, the vibration energy harvesting device of this embodiment is separately provided with a buffer unit for adaptively adjusting the natural vibration frequency of the energy conversion unit, so as to adjust the vibration frequency of the energy conversion unit to be consistent with the vibration frequency of the vibration source, thereby achieving the maximum vibration amplitude of the energy conversion unit when the vibration source has different vibration frequencies, thereby achieving the highest efficiency in power generation or the maximum conversion energy of the vibration energy harvesting device when the vibration source is at different vibration frequencies. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.
[0026] Figure 1 is a schematic diagram of a vibration energy harvesting device provided by an embodiment of the present invention;
[0027] Figure 2 is a schematic diagram of another vibration energy harvesting device provided by an embodiment of the present invention;
[0028] Figure 3 is a schematic diagram of another vibration energy harvesting device provided by an embodiment of the present invention;
[0029] Figure 4 is a schematic diagram of another vibration energy harvesting device provided by an embodiment of the present invention;
[0030] Figure 5 is a schematic diagram of another vibration energy harvesting device provided by an embodiment of the present invention;
[0031] Figure 6 It is a schematic diagram of another vibration energy collection device provided in an embodiment of the present invention. DETAILED DESCRIPTION
[0032] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.
[0033] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0034] See also Figure 1 , this embodiment provides a schematic diagram of a vibration energy collection device, such as Figure 1 As shown, the vibration energy harvesting device 100 includes an energy conversion unit 110 and a buffer unit 120. One end 110A of the energy conversion unit 110 is fixed to the external vibration source 900 to convert the mechanical vibration energy of the vibration source 900 into electrical energy. The other end 110B of the energy conversion unit 110 is coupled to the external vibration source 900 through the buffer unit 120. The buffer unit 120 is used to adaptively adjust the vibration frequency of the energy conversion unit so that the vibration frequency of the energy conversion unit 110 and the vibration frequency of the vibration source 900 remain consistent.
[0035] Optionally, the vibration source 900 may be a means of transportation such as an aircraft, a ship, or a vehicle that generates vibrations during operation, or may be a device such as a wave buoy that generates vibrations according to tidal waves.
[0036] Optionally, the vibration energy collection device 100 may use a piezoelectric conversion device, specifically, a piezoelectric material may be set on the vibration rod of the energy conversion unit 110. When the external vibration source 900 vibrates and drives the vibration rod to vibrate and deform, based on the positive piezoelectric effect of the piezoelectric material, when the piezoelectric material is acted upon by a force, an electric charge will be generated on its surface, thereby converting the vibration energy into electrical energy. Optionally, the energy conversion unit 110 may also use a magnetostrictive conversion structure to generate voltage through the deformation of the magnetostrictive material.
[0037] Compared with the prior art, the vibration energy harvesting device 100 of the present embodiment is separately provided with a buffer unit 120 for adaptively adjusting the natural vibration frequency of the energy conversion unit 110, so as to adjust the vibration frequency of the energy conversion unit 110 to be consistent with the vibration frequency of the vibration source 900, thereby achieving the maximum vibration amplitude of the energy conversion unit 110 under the condition that the vibration source 900 has different vibration frequencies, thereby achieving the highest efficiency of power generation or the maximum conversion energy of the vibration energy harvesting device 100 when the vibration source 900 is at different vibration frequencies.
[0038] For reference Figure 2 Furthermore, the energy conversion unit 110 of the vibration energy harvesting device 200 includes a vibration beam 111 and a mass block 112, the extension direction of the vibration beam 111 is perpendicular to the vibration direction Y of the vibration source 900, one end 111A of the vibration beam 111 is connected to the vibration source 900, and the other end 111B of the vibration beam 111 is fixed to the mass block 112.
[0039] Furthermore, the vibration beam 111 may include an elastic rod 1111 and a piezoelectric converter 1112 fixed integrally with the elastic rod 1111. When the elastic rod 1111 vibrates and bends, the piezoelectric converter 1112 is repeatedly deformed to convert mechanical vibration energy into electrical energy.
[0040] Further, the buffer unit 120 includes a first buffer 121 and a second buffer 122, the first buffer 121 is fixed to the vibration source 900, and the second buffer 122 is fixed to the side of the mass block 112 facing the first buffer 121. Specifically, the vibration source 900 includes a first surface 901 and a second surface 902 adjacent to each other, one end 111A of the vibration beam 111 is connected to the first surface 901, and the first buffer 121 is fixed to the second surface 902. The first buffer 121 and the second buffer 122 can be charge devices or magnetic devices, and the first buffer 121 and the second buffer 122 are attracted or repelled by electrostatic force or magnetic force.
[0041] like Figure 3 As shown, in an alternative embodiment, the second buffer 122 of the vibration energy harvesting device 300 can also be fixed to the side of the vibration beam 111 facing the first buffer 121. The second buffer 122 arranged on the vibration beam 111 can further increase the magnitude of the force and / or adjust the magnitude of the torque between the first buffer 121 and the second buffer 122, so that the vibration energy harvesting device 300 can adjust the vibration frequency in a wider range to better adapt to different vibration frequency conditions of the vibration source.
[0042] like Figure 4As shown, in an alternative embodiment, the first buffer 121 of the vibration energy harvesting device 400 is fixed to the vibration source 900, and the second buffer 122 can also be fixed to the mass block 112 and the side of the vibration beam 111 facing the first buffer 121, so that the vibration energy harvesting device 400 can adjust the vibration frequency within a larger range to better adapt to different vibration frequency conditions of the vibration source 900. .
[0043] like Figure 5 As shown, in one embodiment, the vibration energy harvesting device 500 further includes a buffer control unit 530, and the buffer control unit 530 is used to adjust the electrostatic force or magnetic force between the first buffer 121 and the second buffer 122 to increase the energy conversion efficiency of the energy conversion unit 110. Specifically, taking the electrostatic force as an example, the first buffer 121 and the second buffer 122 include electrode plates arranged opposite to each other, and the electrode plate corresponding to the first buffer 121 is fixedly arranged on the vibration source 900 as a static electrode; the electrode plate corresponding to the second buffer 122 is fixedly arranged on the mass fast 112 and / or the vibration beam 111 ( Figure 4 ) is the moving electrode. The buffer control unit 530 is used to adjust the voltage difference between the first buffer member 121 and the second buffer member 122 to adjust the magnitude of the electrostatic force between the two electrode plates. Specifically, by applying a DC voltage between the moving electrode and the static electrode, it is possible to apply an additional adjustable electrostatic force to the mass block 112, which makes the vibration energy collection device 500 no longer simply sense the vibration force transmitted by the external environment vibration source 900. Since the electrostatic force is applied to the mass block 112, it is equivalent to that the structural stiffness of the vibration energy collection device 500 is adjusted, and the electrostatic force will produce an electrostatic negative stiffness effect on the structure, thereby adjusting the vibration frequency of the vibration energy collection device 500.
[0044] Preferably, in one embodiment, when the buffer unit 120 is not working, the natural vibration frequency of the energy conversion unit 110 is equal to or greater than the maximum vibration frequency of the vibration source 900. Under the action of the buffer unit 120, the natural vibration frequency of the vibration energy collection device 100 can be adjusted between the preset minimum vibration frequency and the maximum vibration frequency to adapt to different vibration environments. Due to the negative stiffness effect generated by the electrostatic force, once the buffer unit 120 starts working, the buffer unit 120 always adjusts the natural vibration frequency of the vibration energy collection device 500 in the direction of reducing its natural vibration frequency. Therefore, the vibration energy collection device 500 of this embodiment needs to design the natural vibration frequency of the energy conversion unit 110 (the initial mechanical frequency when the buffer unit 120 is not working) at the maximum value of the vibration energy frequency of the vibration source 900 or higher. When a DC voltage is applied between the moving electrode and the static electrode, the structure is affected by the electrostatic force (electrostatic negative stiffness effect), and the natural vibration frequency of the vibration energy collection device 500 will be reduced. In this embodiment, the greater the electrostatic force between the moving electrode and the static electrode, the smaller the natural vibration frequency of the vibration energy harvesting device 500. By reasonably adjusting the applied electrostatic force, the natural vibration frequency of the vibration energy harvesting device 500 can be adjusted to be consistent with the vibration frequency of the vibration source 900 at the current moment. When the natural vibration frequency of the vibration energy harvesting device 500 is consistent with the vibration frequency of the vibration source 900 at the current moment, the structure of the vibration energy harvesting device 500 will vibrate together with the vibration source 900 to achieve the same frequency resonance. At this time, the vibration amplitude of the vibration energy harvesting device 500 will reach the maximum, that is, the electrical energy generated by the vibration energy harvesting device 500 can reach the maximum.
[0045] Furthermore, the buffer control unit 530 includes: a voltage conversion unit 531 , a voltage detection unit 532 , an efficiency determination unit 533 and a frequency control unit 534 .
[0046] The voltage conversion unit 531 is used to convert the first voltage generated by the energy conversion unit 110 into a second voltage. In this embodiment, the first voltage generated by the repeated bending of the energy conversion unit 110 is an AC voltage and is output to the voltage conversion unit 531. The voltage conversion unit 531 can be a rectifier circuit, which is used to rectify the AC voltage generated by the energy conversion unit 110 into a DC voltage as the second voltage.
[0047] The voltage detection unit 532 is used to detect the magnitude of the second voltage output by the voltage conversion unit 531 .
[0048] The efficiency determination unit 533 is used to determine the change in conversion efficiency of the energy conversion unit 110 according to the change in the second voltage; specifically, an increase in the second voltage indicates an increase in conversion efficiency, and a decrease in the second voltage indicates a corresponding decrease in conversion efficiency.
[0049] The frequency control unit 534 is used to continuously increase or decrease the voltage difference between the first buffer 121 and the second buffer 122 when the conversion efficiency of the energy conversion unit 110 decreases, so as to increase the conversion efficiency of the energy conversion unit 110 to near a maximum value.
[0050] Specifically, when the second voltage reduction amplitude is greater than the preset threshold, the voltage difference between the first buffer and the second buffer is continuously increased in steps. After each increase in the voltage difference between the first buffer and the second buffer, if the second voltage increases, it indicates that the conversion efficiency is continuously increasing, until the voltage difference between the first buffer and the second buffer is increased, the second voltage decreases, indicating that the conversion efficiency crosses the maximum value and begins to decrease. At this time, the voltage difference between the first buffer and the second buffer is continuously reduced in steps. After each reduction in the voltage difference between the first buffer and the second buffer, if the second voltage increases, it indicates that the conversion efficiency is continuously increasing, until the voltage difference between the first buffer and the second buffer is reduced, the second voltage decreases, indicating that the conversion efficiency crosses the maximum value again and begins to decrease. Then, the above steps are continuously repeated to increase and maintain the conversion efficiency of the energy conversion unit 110 to near the maximum value.
[0051] In one embodiment, the first buffer 121 applies a fixed voltage such as grounding, and the second buffer 122 applies a variable voltage to adjust the voltage difference between the two. Of course, the second buffer 122 may also apply a fixed voltage such as grounding, and the first buffer 121 may apply a variable voltage to adjust the voltage difference between the two.
[0052] See also Figure 6 In one embodiment, the first buffer member 121 and the second buffer member 122 are electrode arrays arranged opposite to each other, and the buffer control unit 530 is used to select a preset number and / or position of electrode pairs to generate electrostatic force, and no electrostatic force is generated between other electrode pairs. Specifically, according to the area of the surface of the mass block 112 facing the vibration source 900, a plurality of second electrodes arranged in a matrix are set, and a plurality of first electrodes arranged in a matrix are fixed on the surface of the mass block 112 corresponding to the vibration source, and the first electrodes and the second electrodes are arranged one by one. In one embodiment, a fixed static voltage is applied to all the second electrodes, such as grounding. Each first electrode selectively applies a fixed voltage or selectively applies a dynamic voltage of adjustable size. Of course, the voltages applied to the first electrode and the second electrode can also be interchanged.
[0053] In this embodiment, the voltage conversion unit 531 is used to convert the first voltage generated by the energy conversion unit 110 into a second voltage. In this embodiment, the first voltage generated by the repeated bending of the energy conversion unit 110 is an AC voltage and is output to the voltage conversion unit 531. The voltage conversion unit 531 can be a rectifier circuit, which is used to rectify the AC voltage generated by the energy conversion unit 110 into a DC voltage as the second voltage.
[0054] The voltage detection unit 532 is used to detect the magnitude of the second voltage output by the voltage conversion unit 531 .
[0055] The efficiency determination unit 533 is used to determine the change in conversion efficiency of the energy conversion unit 110 according to the change in the second voltage; specifically, an increase in the second voltage indicates an increase in conversion efficiency, and a decrease in the second voltage indicates a corresponding decrease in conversion efficiency.
[0056] The frequency control unit 534 is used to continuously increase or decrease the number of electrode pairs that generate electrostatic force to increase the conversion efficiency when the conversion efficiency of the energy conversion unit 110 decreases; and / or continuously increase or decrease the voltage difference between each pair of first electrodes and second electrodes to increase the conversion efficiency of the energy conversion unit 110 to near a maximum value.
[0057] Specifically, when the second voltage reduction amplitude is greater than a preset threshold, the number of electrode pairs generating electrostatic force is continuously increased and / or the voltage difference between each pair of first electrodes and second electrodes is continuously increased. If the second voltage increases after each increase in the number of electrode pairs generating electrostatic force and / or each increase or decrease in the voltage difference between each pair of first electrodes and second electrodes, it indicates that the conversion efficiency is continuously increasing, until the number of electrode pairs generating electrostatic force is increased and / or the voltage difference between each pair of first electrodes and second electrodes is continuously increased, if the second voltage decreases, it indicates that the conversion efficiency crosses the maximum value and begins to decline. At this time, the number of electrode pairs generating electrostatic force is continuously reduced and / or the voltage difference between each pair of first electrodes and second electrodes is continuously reduced. Each time the number of electrode pairs generating electrostatic force is reduced and / or the voltage difference between each pair of first electrodes and second electrodes is continuously reduced, if the second voltage increases, it indicates that the conversion efficiency is continuously increasing, until the number of electrode pairs generating electrostatic force is reduced and / or the voltage difference between each pair of first electrodes and second electrodes is continuously reduced, if the second voltage decreases, it indicates that the conversion efficiency crosses the maximum value again and begins to decline. Then, by continuously repeating the above steps, the conversion efficiency of the energy conversion unit 110 can be increased and maintained near the maximum value, that is, the vibration frequency of the vibration energy collection device 100-600 and the vibration frequency of the vibration source 900 are kept basically consistent.
[0058] In an alternative embodiment, the projection of the arrangement shape of the electrode pairs on the horizontal plane is a central symmetrical matrix pattern, for example, it can be a plurality of uniformly distributed concentric rings, which can be square rings or circular rings, and the electrode pairs are arranged at preset equal intervals on each circular ring. After each increase or decrease in the number of electrode pairs generating electrostatic force, the shape of the electrode pairs maintaining the force is still a central symmetrical matrix pattern. For example, one electrode pair on a concentric ring can be selected to be non-operating at the same time, or two or more electrode pairs on concentric rings can be selected to be non-operating at the same time, so that the force in other directions different from the vibration direction Y can be reduced or avoided, and acts on the center of mass of the mass fast 112 to maintain the stability of the vibration state. Similarly, when the voltage difference between each pair of first electrodes and the second electrode is continuously increased or decreased, the force distribution of the electrode pairs maintaining the force always maintains a central symmetrical matrix pattern, and the direction of the resultant force remains consistent with the vibration direction Y, and acts on the center of mass of the mass fast 112 to maintain the stability of the vibration state.
[0059] In an alternative embodiment, each concentric ring includes at least two groups of staggered and spaced electrode pairs, for example, one group of odd and even numbers, and the odd-numbered electrode pairs can be selected to be non-operating at the same time, thereby halving the electrostatic force between the electrode pairs. In other alternative embodiments, each concentric ring includes n groups of staggered and spaced electrode groups, each group of electrode groups includes a plurality of electrode pairs equally spaced on the ring, and one group or i (n≥i≥1) groups of electrode groups can be controlled to be non-operating at the same time, thereby reducing the electrostatic force between the ring-shaped electrode pairs as a whole to 1 / n or i / n. In this embodiment, the electrode pairs or electrode groups that need to be individually controlled are individually wired with the frequency control unit 534 to facilitate independent selection of control or independent application of voltage.
[0060] Furthermore, the vibration energy harvesting device of any of the above embodiments may also include an energy storage device for storing electrical energy obtained from mechanical energy conversion. The energy storage device may be a capacitor, a battery, a hydrogen energy or physical potential energy storage device, etc.
[0061] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims
1. A vibration energy harvesting device, characterized in that: include: an energy conversion unit, one end of which is fixed to an external vibration source to convert the mechanical vibration energy of the vibration source into electrical energy; A buffer unit, the other end of the energy conversion unit is coupled to an external vibration source through the buffer unit, and the buffer unit is used to adaptively adjust the vibration frequency of the energy conversion unit.
2. The vibration energy harvesting device according to claim 1, characterized in that: The energy conversion unit includes a vibration beam and a mass block. The extension direction of the vibration beam is perpendicular to the vibration direction of the vibration source. One end of the vibration beam is connected to the vibration source, and the other end of the vibration beam is fixed to the mass block.
3. The vibration energy harvesting device according to claim 2, characterized in that: The buffer unit includes a first buffer and a second buffer. The first buffer is fixed to a vibration source, and the second buffer is fixed to a side of the mass block or the vibration beam facing the first buffer.
4. The vibration energy harvesting device according to claim 3, characterized in that: The device further includes a buffer control unit for adjusting the electrostatic force between the first buffer member and the second buffer member to increase the energy conversion efficiency of the energy conversion unit.
5. The vibration energy harvesting device according to claim 4, characterized in that: The first buffer component and the second buffer component include electrode plates arranged opposite to each other, and the buffer control unit is used to adjust the voltage difference between the first buffer component and the second buffer component.
6. The vibration energy harvesting device according to claim 5, characterized in that: The buffer control unit includes: A voltage conversion unit, used to convert the first voltage generated by the energy conversion unit into a second voltage; A voltage detection unit, used for detecting a second voltage output by the voltage conversion unit; an efficiency determination unit, configured to determine a change in the conversion efficiency of the energy conversion unit according to a change in the second voltage; The buffer control unit is used to continuously increase or decrease the voltage difference between the first buffer component and the second buffer component when the conversion efficiency of the energy conversion unit decreases, so as to increase the conversion efficiency of the energy conversion unit to near a maximum value.
7. The vibration energy harvesting device according to claim 4, characterized in that: The first buffer member and the second buffer member are electrode arrays arranged opposite to each other, and the buffer control unit is used to select a preset number and / or position of electrode pairs to generate electrostatic force, and no electrostatic force is generated between other electrode pairs.
8. The vibration energy harvesting device according to claim 7, characterized in that: The buffer control unit comprises: A voltage detection unit, used to detect the voltage value output by the energy conversion unit; an efficiency determination unit, configured to determine a second change in the conversion efficiency of the energy conversion unit according to a first change in the voltage value output by the energy conversion unit within a preset time; A buffer control unit is used to continuously increase or decrease the number of electrode pairs that generate electrostatic force when the conversion efficiency of the energy conversion unit decreases, so as to increase the conversion efficiency; and / or continuously increase or decrease the voltage difference between each pair of first electrodes and second electrodes, so as to increase the conversion efficiency of the energy conversion unit to near a maximum value.
9. The vibration energy harvesting device according to claim 3, characterized in that: The vibration source includes a first surface and a second surface adjacent to each other, one end of the vibration beam is connected to the first surface, and the first buffer is fixed to the second surface.
10. The vibration energy harvesting device according to claim 2, characterized in that: The vibration beam further comprises an elastic rod and a piezoelectric converter fixed integrally with the elastic rod. When the elastic rod vibrates and bends, the piezoelectric converter is repeatedly deformed to convert mechanical vibration energy into electrical energy.