Piezoelectric energy harvester, energy harvesting power supply system and server

Abstract

The application provides a piezoelectric energy collector, an energy collection power supply system and a server, and the piezoelectric energy collector comprises: a metal substrate; and two piezoelectric ceramic sheets attached to the upper surface and the lower surface of the metal substrate respectively, wherein the metal substrate and the two piezoelectric ceramic sheets have a ring structure; and wherein an elastic base is arranged at the first end of the metal substrate, the first end of the metal substrate is connected with the first end of the elastic base, the second end of the elastic base is connected with an external base, and the second end of the metal substrate is connected with a mass. According to the application, the amplitude of the output electric signal and the resonance frequency are effectively reduced by using the elastic base and lead zirconate titanate piezoelectric ceramic, so that the energy collection frequency band and the energy utilization rate are widened, and the voltage amplitude is reduced by using the ring structure to meet the performance requirements of the SoC system under the advanced process, such as low voltage and low power consumption.

Description

Technical Field

[0001] This invention relates to the field of microelectromechanical new energy technology, and more particularly to the field of server power supply system technology, specifically to the field of energy harvesting technology in server power supply systems. Background Technology

[0002] To meet the high performance and stability requirements of servers, server motherboards are operating for increasingly longer periods, handling larger data transfer volumes, and requiring increasingly lower energy dissipation. In the entire server, most of the energy generated by the motherboard system is dissipated as heat and vibration energy. Some heat energy is further converted into vibration energy by fans, which is also not utilized, resulting in low energy efficiency. To extend system operating time and improve energy efficiency, energy is harvested from the motherboard system to achieve self-powering during normal or standby operation. This also requires providing various low power supply voltages (3.3V / 1.8V / 1.2V) to functional chips such as the CPU, GPU, storage, and interfaces. Therefore, servers typically incorporate an energy harvesting power supply system, the entire power supply framework of which includes… Figure 1 As shown.

[0003] In such Figure 1 In the energy harvesting and power supply system shown, the harvester converts vibration energy into an AC (Alternating Current) signal of a certain frequency. Based on the input voltage and current range, the AC / DC (Alternating Current / Direct Current) converter rectifies the AC signal into a stable DC (Direct Current) signal, facilitating energy storage and signal transmission. The DC / DC (Direct Current / Direct Current) regulator performs voltage regulation, outputting a voltage signal matching the required process value and achieving impedance matching between the regulator and subsequent loads, thus better driving the loads.

[0004] Vibration-based energy harvesting methods generally fall into three categories: piezoelectric, electrostatic, and electromagnetic. Compared to electrostatic and electromagnetic methods, piezoelectric energy harvesters based on the positive piezoelectric effect offer advantages such as no electromagnetic interference, environmental friendliness, high energy density, and high integration, making them one of the effective methods for solving this problem. The structure of a traditional cantilever beam piezoelectric energy harvester in existing technology is as follows... Figure 2 As shown.

[0005] Figure 2In the cantilever beam piezoelectric energy harvester, there are upper / lower piezoelectric ceramic plates (PZT1 and PZT2), a metal substrate, a mass block Mt, and a base. a is the acceleration applied at the base, and the load R is the equivalent impedance of components such as AC / DC converter, energy storage, and DC / DC regulator in the energy harvesting system.

[0006] Figure 2 The implementation process of the cantilever beam piezoelectric energy harvester shown is as follows:

[0007] The two piezoelectric ceramic sheets (PZT1 and PZT2) are bonded to the upper and lower surfaces of the metal substrate by an epoxy resin adhesive. The two sheets are polarized oppositely in the z-axis direction (i.e., perpendicular to the metal substrate and the main extension plane of the upper / lower piezoelectric ceramic sheets) and are connected together in series.

[0008] One end of the metal substrate is fixed to the base, while the other end is free.

[0009] The mass block Mt is applied to the metal substrate, which can adjust the resonant frequency to the frequency range required by the power supply signal design.

[0010] An excitation source such as acceleration 'a' is applied to the base, causing the metal substrate to oscillate up and down, which in turn moves the dual piezoelectric ceramic sheets attached to its surface. Under the action of the positive piezoelectric effect, the positive and negative charges generated inside the piezoelectric ceramic sheets accumulate on their upper and lower surfaces, respectively, forming a certain potential difference (U1 and U2).

[0011] The total voltage difference U formed across resistor R is equal to the sum of the potential differences on the surfaces of the two piezoelectric ceramic plates, i.e., U1 + U2.

[0012] Traditional cantilever piezoelectric energy harvesters have a simple structure, but they can only harvest energy from a single direction and require a high supply voltage, making them unsuitable for the low-voltage designs of System-on-Chip (SoC) systems. Furthermore, this structure only provides a single-frequency voltage signal, limiting its applicable frequency band.

[0013] Therefore, in view of the above-mentioned shortcomings and problems in the existing technology, it is necessary to propose an optimized piezoelectric energy harvester and a corresponding energy harvesting power supply system and server, so as to solve the problems of only being able to harvest energy from a single direction, high power supply voltage, only being able to provide voltage signals at a single frequency point, and limited applicable frequency band range. Summary of the Invention

[0014] In view of this, the purpose of this invention is to propose an improved piezoelectric energy harvester, energy harvesting power supply system and server, thereby solving the problems of existing technologies that can only harvest energy from a single direction, have high power supply voltage, can only provide voltage signals at a single frequency point, and have limited applicable frequency band range.

[0015] To achieve the above objectives, in one aspect, the present invention provides a piezoelectric energy harvester, wherein the piezoelectric energy harvester comprises:

[0016] Metal substrate; and

[0017] Two piezoelectric ceramic sheets are respectively attached to the upper and lower surfaces of the metal substrate.

[0018] The metal substrate and the two piezoelectric ceramic sheets have an annular structure; and

[0019] Wherein, an elastic substrate is disposed at a first end of the metal substrate and the first end of the metal substrate is connected to the first end of the elastic substrate, and the second end of the elastic substrate is connected to an external base; and

[0020] The second end of the metal substrate is connected to the mass block.

[0021] In some embodiments of the piezoelectric energy harvester according to the present invention, the mass block generates stress under the action of acceleration.

[0022] In some embodiments of the piezoelectric energy harvester according to the present invention, an acceleration is applied to the elastic substrate by the external base, causing the elastic substrate to undergo simple harmonic motion.

[0023] In some embodiments of the piezoelectric energy harvester according to the present invention, the elastic substrate drives the metal substrate, the two piezoelectric ceramic sheets and the mass block to vibrate, and under stress, the two piezoelectric ceramic sheets produce stress deformation of different degrees, thereby forming different potentials under the action of the positive piezoelectric effect.

[0024] In some embodiments of the piezoelectric energy harvester according to the present invention, the two piezoelectric ceramic sheets are respectively bonded to the upper and lower surfaces of the metal substrate by an epoxy resin adhesive.

[0025] In some embodiments of the piezoelectric energy harvester according to the present invention, the two piezoelectric ceramic sheets respectively have an outer surface coupling point and an inner surface coupling point.

[0026] In some embodiments of the piezoelectric energy harvester according to the present invention, the inner surface coupling points of the two piezoelectric ceramic sheets are connected in series with each other by a wire, and the outer surface coupling points of the two piezoelectric ceramic sheets respectively constitute the positive output terminal and the negative output terminal.

[0027] In some embodiments of the piezoelectric energy harvester according to the invention, the acceleration applied to the elastic substrate varies depending on the vibration environment.

[0028] In another aspect, the present invention provides an energy harvesting and power supply system, wherein the energy harvesting and power supply system has the following components connected in sequence: a piezoelectric energy harvester, an AC-DC converter, an energy storage device, a DC regulator, and a load as described in any of the foregoing embodiments.

[0029] In another aspect, the present invention provides a server having an energy harvesting and power supply system, wherein the energy harvesting and power supply system has the following components electrically connected in sequence: a piezoelectric energy harvester, an AC-DC converter, an energy storage device, a DC regulator, and a load as described in any of the foregoing embodiments.

[0030] This invention offers at least the following beneficial technical effects: According to this invention, an elastic substrate and lead zirconate titanate piezoelectric ceramics are used to broaden the energy harvesting bandwidth and energy utilization rate. Furthermore, a ring structure is used to reduce the voltage amplitude to meet the low-voltage, low-power performance requirements of SoC systems under advanced processes. Specifically, this invention proposes a low-voltage, wideband piezoelectric energy harvester based on an elastic substrate and a ring structure. The ring structure replaces the cantilever beam structure, and the piezoelectric ceramic sheet generates positive and negative charges with varying degrees of concentration based on the vibration strain at different locations, effectively reducing the amplitude and resonant frequency of the output electrical signal. Simultaneously, the elastic substrate fully utilizes simple harmonic motion to broaden the bandwidth, enabling the output of various AC signals. In other words, this invention cleverly combines a ring structure and an elastic substrate to realize a low-voltage, wideband ring piezoelectric energy harvester suitable for SoC systems. This not only effectively reduces the design difficulty of AC / DC converters and DC / DC regulators by lowering the voltage amplitude but also significantly broadens the output signal bandwidth using simple harmonic motion, making it more suitable for application in SoC systems. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained based on these drawings without creative effort.

[0032] In the diagram:

[0033] Figure 1 A schematic block diagram of an energy harvesting and power supply system is shown.

[0034] Figure 2 A schematic diagram of a cantilever beam piezoelectric energy harvester in the prior art is shown;

[0035] Figure 3 A schematic diagram of an embodiment of a piezoelectric energy harvester according to the present invention is shown;

[0036] Figure 4 A schematic diagram of the fourth-order vibration mode of the piezoelectric energy harvester according to the present invention is shown;

[0037] Figure 5 A schematic diagram illustrating the relationship between output voltage and frequency of a prior art piezoelectric energy harvester according to the present invention is shown.

[0038] Figure 6 A schematic diagram of an embodiment of the energy harvesting and power supply system according to the present invention is shown;

[0039] Figure 7 A schematic diagram of an embodiment of a server according to the present invention is shown. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to specific examples and the accompanying drawings.

[0041] It should be noted that all uses of the terms "first" and "second" in the embodiments of the present invention are for the purpose of distinguishing two different entities or different parameters with the same name. Therefore, "first" and "second" are merely for convenience of expression and should not be construed as limiting the embodiments of the present invention. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process that includes a series of steps or units, a piezoelectric energy harvester, a system, a product, or other steps or units inherent in the device.

[0042] Traditional cantilever piezoelectric energy harvesters only achieve vibration in one direction (such as the z-axis), which restricts the degree of freedom of vibration and results in a narrow bandwidth for the output electrical signal. At the same time, their output voltage is relatively high, which increases the design difficulty of AC / DC converters and DC / DC regulators, and requires multi-stage DC / DC regulators to meet the low voltage requirements and impedance matching requirements of SoC systems.

[0043] This invention proposes a low-voltage, wide-bandwidth ring piezoelectric energy harvester adapted to SoC systems based on a ring structure and an elastic matrix.

[0044] In the piezoelectric energy harvester according to the present invention, the overall structure is a ring structure. The metal substrate drives the two piezoelectric ceramic sheets to undergo different stress deformations, generating different degrees of positive and negative charges at different positions, forming potential differences of varying magnitudes and polarities. The amplitude of the output voltage is reduced by merging these potential differences. At the same time, the elastic matrix drives the mass block Mt to perform simple harmonic motion. When moving away from the equilibrium position, the acceleration increases, and the stress deformation of the metal substrate reaches its maximum, thus widening the frequency band.

[0045] Therefore, in a first aspect, the present invention provides a piezoelectric energy harvester 100. Figure 3 A schematic diagram of an embodiment of a piezoelectric energy harvester 100 according to the present invention is shown. Figure 3 In the illustrated embodiment, the piezoelectric energy harvester 100 includes:

[0046] Metal substrate 110; and

[0047] Two piezoelectric ceramic sheets 120 are respectively attached to the upper and lower surfaces of the metal substrate 110.

[0048] The metal substrate 110 and the two piezoelectric ceramic sheets 120 have an annular structure; and

[0049] Wherein, an elastic substrate 130 is disposed at the first end 111 of the metal substrate 110, and the first end 111 of the metal substrate 110 is connected to the first end 131 of the elastic substrate 130, and the second end 132 of the elastic substrate 130 is connected to an external base; and

[0050] The second end 112 of the metal substrate 110 is connected to the mass block 140.

[0051] Specifically, unlike the traditional cantilever beam structure, the present invention changes the structure of the metal substrate 110 and the two piezoelectric ceramic sheets (PZT1 and PZT2) 120 attached to the upper and lower surfaces of the metal substrate 110 into a ring structure, thereby transforming the stress deformation from vertical vibration into multiple stress deformations of different degrees.

[0052] Furthermore, the metal substrate 110 has a first end 111 and a second end 112, and due to the annular structure of the metal substrate 110, preferably the first end 111 and the second end 112 of the metal substrate 110 are on the same horizontal plane, and the position of the second end 112 is outside the first end 111, that is, there is an offset in the direction of the annular plane, so as to facilitate the application of the mass block (Mt) 140.

[0053] Further, see Figure 3 In an embodiment of the piezoelectric energy harvester 100 of the present invention, an elastic matrix 130 is added at the first end 111 of the metal substrate 110, and a mass block (Mt) 140 is applied at the second end 112 of the metal substrate 110.

[0054] In addition, the added elastic substrate 130 also has a first end 131 and a second end 132, and the first end 131 of the elastic substrate 130 is connected to the first end 111 of the metal substrate 110, while the second end 132 of the elastic substrate 130 is connected to an external base (not shown).

[0055] In the piezoelectric energy harvester 100 according to the invention, the mass block 140 generates stress F under the action of acceleration, where m is the mass of the mass block Mt. This stress eventually acts on the two piezoelectric ceramic sheets 120, thereby generating strain. Therefore, in some embodiments of the piezoelectric energy harvester 100 according to the invention, the mass block 140 generates stress under the action of acceleration.

[0056] Furthermore, in the piezoelectric energy harvester 100 according to the invention, an acceleration a is applied to the elastic substrate 130, which can be provided by an external base (not shown). Under a certain acceleration a, the elastic substrate 130 undergoes simple harmonic motion. Therefore, in some embodiments of the piezoelectric energy harvester 100 according to the invention, an acceleration is applied to the elastic substrate 130 by the external base, causing the elastic substrate 130 to undergo simple harmonic motion.

[0057] Furthermore, the elastic substrate 130 drives the vibration of components such as the metal substrate 110, piezoelectric ceramic sheets (PZT1 and PZT2) 120, and mass block 140, under stress F (=ma 2 Under the action of stress, the piezoelectric ceramic sheets (PZT1 and PZT2) 120 undergo different degrees of stress deformation, thereby generating different potentials under the positive piezoelectric effect. Therefore, in some embodiments of the piezoelectric energy harvester 100 according to the present invention, the elastic substrate 130 drives the metal substrate 110, the two piezoelectric ceramic sheets 120, and the mass block 140 to vibrate, and under stress, causes the two piezoelectric ceramic sheets 120 to undergo different degrees of stress deformation, thereby generating different potentials under the positive piezoelectric effect.

[0058] In addition, during the finite element simulation, additional material types and corresponding characteristic attributes, along with mesh generation, are applied to each component. Specifically, the piezoelectric ceramic sheets (PZT1 and PZT2) 120, the metal substrate 110, the mass block 140, and the load impedance are made of solid5, solid45, mass21, and circu94 materials, respectively. For the piezoelectric ceramic sheets, additional characteristic attributes are added, such as dielectric constant, stress constant, and elastic stiffness constant, as shown below. Mesh generation is performed on each component to ensure the accuracy of the finite element simulation structure.

[0059] The material properties of the piezoelectric ceramic sheet (PZT-5A) include:

[0060] Dielectric constant:

[0061] EMUNIT, EPZRO, 8.854E-12

[0062] MP,PERX,1,1.730E3

[0063] MP,PERY,1,1.730E3

[0064] MP,PERZ,1,1.700E3;

[0065] Elastic stiffness coefficient, N / m^2:

[0066] TB,ANEL,1

[0067] TBDATA,1,12.1E10,7.54E10,7.52E10

[0068] TBDATA,7,12.1E10,7.52E10

[0069] TBDATA,12,11.1E10

[0070] TBDATA,16,2.26E10

[0071] TBDATA,19,2.11E10

[0072] TBDATA,21,2.11E10;

[0073] Piezoelectric (stress) constant, C / m^2:

[0074] Tb,PIEZ,1

[0075] TBDATA,3,-5.4

[0076] TBDATA,6,-5.4

[0077] TBDATA,9,15.8

[0078] TBDATA,14,12.3

[0079] TBDATA,16,12.3.

[0080] Furthermore, the piezoelectric ceramic sheets (PZT1 and PZT2) 120 are preferably made of lead zirconate titanate piezoelectric ceramic, and the annular piezoelectric ceramic sheets (PZT1 and PZT2) 120 are bonded to the upper and lower surfaces of the metal substrate 110 using an epoxy resin adhesive. Therefore, in some embodiments of the piezoelectric energy harvester 100 according to the present invention, the two piezoelectric ceramic sheets 120 are respectively bonded to the upper and lower surfaces of the metal substrate 110 using an epoxy resin adhesive.

[0081] In addition, electrical coupling and electrical connections to external circuits are required between the two piezoelectric ceramic sheets (PZT1 and PZT2) 120. Each surface of the piezoelectric ceramic sheets (PZT1 and PZT2) 120 is electrically coupled, such as... Figure 3 The embodiments shown include nodes A, B, C, and D, where nodes A and B are the outer surface coupling point A and inner surface coupling point B of the upper piezoelectric ceramic sheet (PZT1) 120, respectively, and nodes C and D are the inner surface coupling point C and outer surface coupling point D of the lower piezoelectric ceramic sheet (PZT2) 120, respectively. Through these four nodes A, B, C, and D, the potentials of different nodes on the same surface are combined. The inner surface coupling points B and C of the upper and lower piezoelectric ceramic sheets (PZT1 and PZT2) 120 are connected in series with each other by wires, and the outer surface coupling points A and D constitute the positive and negative terminals of the output electrical signal. The two output terminals form ports for connecting components such as AC / DC converters and DC / DC regulators, which have an equivalent impedance R. Therefore, in some embodiments of the piezoelectric energy harvester 100 according to the present invention, the two piezoelectric ceramic sheets 120 respectively have outer surface coupling points A and D and inner surface coupling points B and C. Furthermore, in some embodiments of the piezoelectric energy harvester 100 according to the present invention, the inner surface coupling points B and C of the two piezoelectric ceramic sheets 120 are connected in series with each other by wires, and the outer surface coupling points A and D of the two piezoelectric ceramic sheets 120 respectively constitute the positive output terminal and the negative output terminal.

[0082] Furthermore, the acceleration 'a' applied to the elastic substrate 130 can be provided by an external base or varied depending on the vibration environment. Moreover, one end of the elastic substrate 130 connected to the external base (i.e., the second end 132) is subject to no degree-of-freedom constraint, while the other end (i.e., the first end 131) is subject to a z-direction degree-of-freedom constraint. The metal substrate 110, the piezoelectric ceramic sheet 120, and the mass block 140 are subject to x, y, and z-direction degree-of-freedom constraints. Therefore, in some embodiments of the piezoelectric energy harvester 100 according to the present invention, the acceleration applied to the elastic substrate 130 varies depending on the vibration environment.

[0083] Unless otherwise stated, the x, y, and z directions mentioned in the context can be referred to as Figure 4 The coordinate axes are shown in the figure.

[0084] Furthermore, under a certain acceleration, the elastic matrix 130 undergoes simple harmonic motion, causing the metal substrate 110 and the piezoelectric ceramic sheet 120 to vibrate, such as... Figure 4 As shown. Figure 4 A schematic diagram of the fourth vibration mode of the piezoelectric energy harvester according to the present invention is shown, wherein the natural frequency of the fourth vibration mode is 43.7 Hz. The upper and lower piezoelectric ceramic plates 120 generate a certain potential under the action of the positive piezoelectric effect, which constitutes the voltage across the load impedance R.

[0085] Therefore, the piezoelectric energy harvester 100 according to the present invention can not only output a low voltage signal, but also broaden the frequency band of the electrical signal and improve the energy utilization rate of the system by utilizing the elastic matrix 130.

[0086] Figure 5 A schematic diagram illustrating the relationship between output voltage and frequency of a piezoelectric energy harvester 100 according to the prior art and the present invention is shown. Figure 5 It is evident that the output voltage of the conventional structure is approximately six times that of the ring piezoelectric energy harvester without an elastic matrix, indicating that the ring structure effectively reduces the output voltage amplitude. The application of the elastic matrix 130 not only appropriately increases the voltage amplitude but also broadens the frequency of the output signal (approximately 4.8 Hz), thus solving the single-point frequency output problem.

[0087] In summary, this invention proposes a low-voltage, wideband ring-shaped piezoelectric energy harvester, particularly suitable for SoC systems, based on a ring structure and an elastic substrate. The overall ring structure allows for multi-directional vibration, inducing stress deformation at multiple points of varying degrees and generating positive and negative charges with different concentrations. This avoids stress deformation in a single direction, effectively reducing the voltage amplitude of the output signal and thus simplifying the design of AC / DC converters and DC / DC regulators. Simultaneously, the elastic substrate drives the mass block Mt in simple harmonic motion, broadening the frequency band and making it fully applicable to SoC systems. According to this invention, the elastic substrate and lead zirconate titanate piezoelectric ceramic are used to broaden the energy harvesting bandwidth and energy utilization rate, while the ring structure reduces the voltage amplitude to meet the low-voltage, low-power performance requirements of SoC systems under advanced processes.

[0088] In a second aspect, the present invention also provides an energy harvesting and power supply system 200. Figure 6 A schematic diagram of an embodiment of the energy harvesting and power supply system 200 according to the present invention is shown. Figure 6 As shown, the energy harvesting and power supply system 200 has the following components connected in sequence: a piezoelectric energy harvester 100 according to any of the foregoing embodiments, an AC / DC converter 210, an energy storage device 220, a DC regulator 230, and a load 240. According to the present invention, the piezoelectric energy harvester 100 includes:

[0089] Metal substrate 110; and

[0090] Two piezoelectric ceramic sheets 120 are respectively attached to the upper and lower surfaces of the metal substrate 110.

[0091] The metal substrate 110 and the two piezoelectric ceramic sheets 120 have an annular structure; and

[0092] Wherein, an elastic substrate 130 is disposed at the first end 111 of the metal substrate 110, and the first end 111 of the metal substrate 110 is connected to the first end 131 of the elastic substrate 130, and the second end 132 of the elastic substrate 130 is connected to an external base; and

[0093] The second end 112 of the metal substrate 110 is connected to the mass block 140.

[0094] To meet the high performance and high stability requirements of servers, server motherboards are operating for increasingly longer periods, handling larger data transfer volumes, and requiring increasingly lower energy dissipation. In the entire server, most of the energy generated by the motherboard system is dissipated as heat and vibration energy. Some heat energy is further converted into vibration energy by fans, which is also not utilized, resulting in low energy efficiency. To extend system operating time and improve energy efficiency, energy is harvested from the motherboard system to achieve self-powering during normal or standby operation. Furthermore, various low power supply voltages (3.3V / 1.8V / 1.2V, etc.) are provided to functional chips such as the CPU, GPU, storage, and interfaces. This invention provides an energy harvesting power supply system 200 to collect and regulate the dissipated energy, especially vibration energy, in the server. Figure 6 As shown, the piezoelectric energy harvester 100 converts vibration energy into an AC signal of a certain frequency. Based on the input voltage and current range, the AC / DC converter 210 rectifies the AC signal into a stable DC signal, facilitating energy storage in the energy storage unit 220 and remote signal transmission. The DC / DC regulator 230 performs voltage regulation, outputting an electrical signal with the required process voltage value and achieving impedance matching between the regulator and the subsequent load, which is more conducive to driving the subsequent load 240.

[0095] Because the energy harvesting power supply system 200 according to the present invention has a piezoelectric energy harvester 100 according to the present invention, and the low-voltage broadband ring piezoelectric energy harvester based on the ring structure and elastic matrix proposed by the present invention is particularly suitable for SoC systems, the piezoelectric energy harvester adopts a ring structure as a whole. Multi-directional vibration causes stress deformation of different degrees at multiple locations, generating positive and negative charges of different concentrations. Therefore, the energy harvesting power supply system 200 according to the present invention and the server 300 according to the present invention also have the following advantages and improvements: namely, avoiding stress deformation in one direction, effectively reducing the voltage amplitude of the output signal, and thus reducing the design difficulty of AC / DC converters and DC / DC regulators. At the same time, the elastic matrix drives the mass block Mt to perform simple harmonic motion, widening the frequency band, which can be fully applied to SoC systems. According to the present invention, the energy harvesting frequency band and energy utilization rate are widened by using an elastic matrix and lead zirconate titanate piezoelectric ceramics, and the voltage amplitude is reduced by using a ring structure to meet the performance requirements of low voltage and low power consumption of SoC systems under advanced processes.

[0096] A third aspect of the present invention also provides a server 300. Figure 7 A schematic diagram of an embodiment of a server according to the present invention is shown. (As shown) Figure 7 As shown, the server 300 has an energy harvesting and power supply system 200, wherein the energy harvesting and power supply system 200 has the following components electrically connected in sequence: a piezoelectric energy harvester 100 according to any of the foregoing embodiments, an AC / DC converter 210, an energy storage device 220, a DC regulator 230, and a load 240. According to the present invention, the piezoelectric energy harvester 100 includes:

[0097] Metal substrate 110; and

[0098] Two piezoelectric ceramic sheets 120 are respectively attached to the upper and lower surfaces of the metal substrate 110.

[0099] The metal substrate 110 and the two piezoelectric ceramic sheets 120 have an annular structure; and

[0100] Wherein, an elastic substrate 130 is disposed at the first end 111 of the metal substrate 110, and the first end 111 of the metal substrate 110 is connected to the first end 131 of the elastic substrate 130, and the second end 132 of the elastic substrate 130 is connected to an external base; and

[0101] The second end 112 of the metal substrate 110 is connected to the mass block 140.

[0102] To meet the high performance and high stability requirements of servers, server motherboards are operating for increasingly longer periods, handling larger data transfer volumes, and requiring increasingly lower energy dissipation. In the entire server, most of the energy generated by the motherboard system is dissipated as heat and vibration energy. Some heat energy is further converted into vibration energy by fans, which is also not utilized, resulting in low energy efficiency. To extend system operating time and improve energy efficiency, energy is harvested from the motherboard system to achieve self-powering during normal or standby operation. Furthermore, various low power supply voltages (3.3V / 1.8V / 1.2V, etc.) must be provided to functional chips such as the CPU, GPU, storage, and interfaces. According to this invention, an energy harvesting and power supply system 200 is incorporated into the server 300 to collect and regulate the dissipated energy, especially vibration energy, within the server. Figure 7 As shown, the piezoelectric energy harvester 100 converts vibration energy into an AC signal of a certain frequency. Based on the input voltage and current range, the AC / DC converter 210 rectifies the AC signal into a stable DC signal, facilitating energy storage in the energy storage unit 220 and remote signal transmission. The DC / DC regulator 230 performs voltage regulation, outputting an electrical signal with the required process voltage value and achieving impedance matching between the regulator and the subsequent load, which is more conducive to driving the subsequent load 240.

[0103] Since the server 300 according to the present invention has a piezoelectric energy harvester 100 according to the present invention, and the present invention proposes a low-voltage broadband ring piezoelectric energy harvester based on a ring structure and an elastic substrate, which is particularly suitable for SoC systems, the piezoelectric energy harvester adopts a ring structure as a whole. Multi-directional vibration causes stress deformation of different degrees at multiple locations, generating positive and negative charges of different concentrations. This makes the energy harvesting power supply system 200 according to the present invention and the server 300 according to the present invention have the same advantages and improvements, namely, avoiding stress deformation in one direction, effectively reducing the voltage amplitude of the output signal, and thus reducing the design difficulty of AC / DC converters and DC / DC regulators. At the same time, the elastic substrate drives the mass block Mt to perform simple harmonic motion, widening the frequency band, which can be fully applied to SoC systems. According to the present invention, the energy harvesting frequency band and energy utilization rate are widened by using an elastic substrate and lead zirconate titanate piezoelectric ceramics, and the voltage amplitude is reduced by using a ring structure to meet the performance requirements of low voltage and low power consumption of SoC systems under advanced processes.

[0104] Those skilled in the art will also understand that the various exemplary logic blocks, modules, circuits, and algorithm steps described in conjunction with the disclosure herein can be implemented as electronic hardware, computer software, or a combination of both. To clearly illustrate this interchangeability between hardware and software, the functionality of various illustrative components, blocks, modules, circuits, and steps has been generally described. Whether this functionality is implemented as software or as hardware depends on the specific application and the design constraints imposed on the system as a whole. Those skilled in the art can implement the functionality in various ways for each specific application, but such implementation decisions should not be construed as departing from the scope of the embodiments disclosed herein.

[0105] The above are exemplary embodiments disclosed in this invention. However, it should be noted that various changes and modifications can be made without departing from the scope of the embodiments of this invention as defined by the claims. The functions, steps, and / or actions of the piezoelectric energy harvester according to the disclosed embodiments described herein do not need to be performed in any particular order. Furthermore, although the elements disclosed in the embodiments of this invention may be described or claimed individually, they may be understood as multiple unless explicitly limited to a singular number.

[0106] It should be understood that, as used herein, the singular form "a" is intended to include the plural form as well, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations of one or more of the associatedly listed items. The embodiment numbers disclosed above are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0107] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples. Within the framework of the invention, technical features of the above embodiments or different embodiments can be combined, and many other variations of different aspects of the invention exist, which are not provided in the details for the sake of brevity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the invention should be included within the protection scope of the invention.

Claims

1. A piezoelectric energy harvester, characterized in that, The piezoelectric energy harvester includes: Metal substrate; and Two piezoelectric ceramic sheets are respectively attached to the upper and lower surfaces of the metal substrate. The metal substrate and the two piezoelectric ceramic sheets have an annular structure; and Wherein, an elastic substrate is disposed at a first end of the metal substrate and the first end of the metal substrate is connected to the first end of the elastic substrate, and the second end of the elastic substrate is connected to an external base; and The second end of the metal substrate is connected to the mass block; The mass block generates stress under the action of acceleration; The external base applies acceleration to the elastic matrix, causing the elastic matrix to undergo simple harmonic motion. The elastic matrix drives the metal substrate, the two piezoelectric ceramic sheets and the mass block to vibrate, and under stress, the two piezoelectric ceramic sheets produce different degrees of stress deformation, thereby forming different potentials under the action of the positive piezoelectric effect. The two piezoelectric ceramic sheets each have an outer surface coupling point and an inner surface coupling point; The inner surface coupling points of the two piezoelectric ceramic sheets are connected in series with each other by a wire, and the outer surface coupling points of the two piezoelectric ceramic sheets respectively constitute the positive output terminal and the negative output terminal.

2. The piezoelectric energy harvester according to claim 1, characterized in that, The two piezoelectric ceramic sheets are bonded to the upper and lower surfaces of the metal substrate respectively using an epoxy resin adhesive.

3. The piezoelectric energy harvester according to claim 1, characterized in that, The acceleration applied to the elastic matrix varies depending on the vibration environment.

4. An energy harvesting and power supply system, characterized in that, The energy harvesting and power supply system has the following components that are electrically connected in sequence: The piezoelectric energy harvester, AC / DC converter, energy storage device, DC regulator, and load according to any one of claims 1-3.

5. A server, the server having an energy harvesting power supply system, characterized in that, The energy harvesting and power supply system has the following components that are electrically connected in sequence: The piezoelectric energy harvester, AC / DC converter, energy storage device, DC regulator, and load according to any one of claims 1-3.

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