Method and apparatus for generating electricity using impact energy

Abstract

The application discloses a kind of power generation method and device using impact energy, utilize isotropic pressure change to drive the magnetic phase change of pressure-sensitive magnetic composite material, make its magnetic flux density change;The pressure-sensitive magnetic composite material includes magnetic intermetallic compound Mn-Co-Si-Ge and solid-state pressure conduction medium.The application uses solid-state pressure conduction medium, and converts impact force in uniaxial direction into isotropic pressure change, so there is no special requirement for the mechanical strength of Mn-Co-Si-Ge alloy particles, with the advantage of strong bearing capacity;And the Mn-Co-Si-Ge alloy used is transition intermetallic compound, and the material cost is lower.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of power generation, and particularly relates to a method and device for generating electricity by using impact energy. BACKGROUND

[0002] When a punch press, a pile driver, a freight railway locomotive, a heavy truck or the like is in operation, a strong impact force is generated on each component, a base and the ground, and the impact energy is propagated in the form of mechanical vibration, resulting in strong noise and heat energy dissipated to the surrounding environment. The above-mentioned equipment often adopts thick and heavy structural members to cope with the strong impact during operation. If the impact energy can be recovered to some extent and converted into electrical energy output, not only some vibration reduction and noise reduction effects will be produced to alleviate the potential damage of the impact force to each component, but also the light weight and compactness of the equipment will be helpful. In addition, the voltage or current converted from the vibration energy can also be used as a vibration sensing signal to monitor the operating state of the equipment.

[0003] The impact energy has the characteristics of short movement stroke, short action time and high instantaneous force value. The traditional power generation device is based on the relative motion of the induction coil in the magnetic field to generate a dynamic electromotive force, and requires a driving force to generate a large movement stroke, so it is difficult to be directly used for the collection of impact energy. At present, there are the following common technical solutions for pressure power generation. One is to use a lever, a gear or the like to amplify the displacement of the induction coil relative to the magnetic field, and to realize the output of voltage based on the principle of dynamic electromotive force. Due to the inertia of the movement mechanism itself, the response speed of this kind of device to the instantaneous force is slow, and the conduction efficiency of the impact energy is low. Another technical solution for pressure power generation is based on the piezoelectric effect of ceramic, polymer and the like. Although this solution does not depend on the movement stroke, the mechanical bearing capacity of the piezoelectric material is relatively low, and under the action of the instantaneous strong impact, there is a high probability of damage. In addition, the magnetic anisotropy coefficient of the magnetostrictive material changes with the uniaxial pressure, which can also realize pressure power generation, but the common magnetostrictive alloys such as Td-Dy-Fe alloy and Fe-Ga alloy contain a large amount of high-valence metal elements, and their performance is highly dependent on the specific grain arrangement, so the preparation cost of the material is high, which limits its application prospect. SUMMARY

[0004] Therefore, the present application provides a method for generating electricity by using impact energy, which utilizes the isotropic pressure change to drive the magnetic phase change of a pressure-sensitive magnetic composite material, so that the magnetic flux density of the pressure-sensitive magnetic composite material changes; the pressure-sensitive magnetic composite material comprises a magnetic intermetallic compound Mn-Co-Si-Ge and a solid-state pressure conduction medium.

[0005] Preferably, the chemical formula of the magnetic intermetallic compound is MnCoSi 1-x Ge Xwherein x ranges from 0 to 0.25, and has both anti-ferromagnetic and ferrimagnetic magnetic states.

[0006] Preferably, the magnetic intermetallic compound has a higher initial permeability and magnetization under a pressure higher than a preset condition than under a pressure lower than the preset condition, and the magnetic properties change reversibly with the pressure condition.

[0007] Preferably, the solid-state pressure-conducting medium comprises a main group metal element such as indium or tin or aluminum or an alloy thereof.

[0008] Preferably, the solid-state pressure-conducting medium comprises paraffin or solid grease or polymer or boron nitride powder.

[0009] To achieve the above-mentioned power generation method, the application also provides a power generation device using impact energy, which comprises a pressure-sensitive magnetic composite material loaded in a pressure-bearing cavity and a piston component capable of exerting a uniaxial impact force on the pressure-sensitive magnetic composite material.

[0010] Preferably, the side wall of the pressure-bearing cavity comprises a magnetic conducting component and a non-magnetic component, wherein the magnetic conducting component serves as a pair of magnetic poles to provide a magnetic field perpendicular to the external pressure direction for the pressure-sensitive magnetic composite material in the pressure-bearing cavity.

[0011] Preferably, the pressure-bearing cavity and a magnetic core with an induction coil wound thereon are connected in parallel in a magnetic circuit structure, forming two branches, and when the magnetic flux of the branch with the pressure-bearing cavity increases, the magnetic flux in the induction coil decreases; vice versa.

[0012] Preferably, an adjustable gap is provided to adjust the magnetic resistance of the branch with the induction coil, so as to balance the magnetic flux density distribution of the branch with the pressure-bearing cavity and the branch with the induction coil.

[0013] Preferably, a permanent magnet is used to provide a magnetic potential for the two branches.

[0014] The power generation process of the device is as follows. Under normal pressure conditions, the permeability and saturation magnetization of the magnetic intermetallic compound are relatively low, and the magnetic resistance of the pressure-bearing cavity is relatively high, so most of the magnetic flux flows through the induction coil branch; under high pressure conditions, the permeability and saturation magnetization of the magnetic intermetallic compound are relatively high, and the magnetic resistance of the pressure-bearing cavity is relatively low, so part of the magnetic flux is transferred from the induction coil branch to the branch with the pressure-bearing cavity. It can be seen that under the action of the impact force, i.e. the process of rapid application and removal of external pressure, the magnetic flux in the induction coil also rapidly decreases and increases, thereby outputting a group of voltage pulses and realizing the conversion of impact energy to electric energy.

[0015] Compared with the prior art, the present application has at least the following beneficial effects: the magnetic intermetallic compound Mn-Co-Si-Ge used in the present application is a magnetic phase change alloy material which is sensitive to the change of external pressure. The application of pressure can drive the transition from the antiferromagnetic state to the ferromagnetic state, and the above transition can be restored when the change of pressure is removed.

[0016] The present application uses solid-state materials with certain fluidity, ductility or deformation ability under pressure as pressure conduction media, which can convert the axial impact force applied by the piston device into uniform pressure changes and conduct them to the alloy particles from all directions.

[0017] The pressure-sensitive magnetic material and the induction coil of the present application are located in two mutually parallel magnetic flux branches, respectively. The change of external pressure drives the transfer of magnetic flux in the two branches, realizing the change of magnetic flux in the induction coil. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to make the purpose, technical scheme and beneficial effects of the present application clearer, the present application provides the following drawings for illustration:

[0019] Figure 1 Structure diagram of the impact energy power generation device of the embodiment of the present application;

[0020] Figure 2 Structure diagram of the pressure-bearing cavity of the impact energy power generation device of the embodiment of the present application;

[0021] Figure 3 Structure diagram of the magnetic circuit of the impact energy power generation device of the embodiment of the present application;

[0022] Figure 4 Magnetic intermetallic compound MnCoSi 0.88 Ge 0.12 Magnetization M-T curve of the magnetic intermetallic compound MnCoSi

[0023] Figure 5 Magnetic intermetallic compound MnCoSi 0.88 Ge 0.12 Magnetization curve under the conditions of normal pressure and high pressure and at a temperature of 280K;

[0024] Figure 6 Variation diagram of the magnetic flux density B in the pressure-sensitive magnetic composite material of the embodiment of the present application with the gap under two pressure conditions, obtained by simulating the magnetic circuit by the finite element method;

[0025] Figure 7The figure is a graph of the relationship between the magnetic flux density B in the magnetic core of the inductive coil of one embodiment of the application and the gap under two pressure conditions, obtained by simulating the magnetic circuit using the finite element method.

[0026] Figure 8 The figure is a graph of the relationship between the magnetic flux density change amount ΔB in the magnetic core of the inductive coil of one embodiment of the application and the gap under two pressure conditions, obtained by simulating the magnetic circuit using the finite element method.

[0027] Figure 9 The figure is a graph of the relationship between the measured input pressure P and the measured output voltage V of one embodiment of the application.

[0028] Figure 10 The figure is a graph of the relationship between the measured output voltage peak value V peak and the gap. DETAILED DESCRIPTION

[0029] The preferred embodiments of the application will be described in detail below with reference to the accompanying drawings.

[0030] The application provides a method for generating electricity using impact energy, which drives the magnetic phase change of a pressure-sensitive magnetic composite material using isotropic pressure change, so that the magnetic flux density of the pressure-sensitive magnetic composite material changes; the pressure-sensitive magnetic composite material comprises a magnetic intermetallic compound Mn-Co-Si-Ge and a solid-state pressure conduction medium.

[0031] Referring to Figures 1-3 , the figure is a structural schematic diagram of the device, and the reference signs are as follows: a magnetic conductive pole plate 1, a non-magnetic cylinder wall 2, a pressure-sensitive magnetic composite material 3, a piston component 4, a non-magnetic base 5, a magnetic conductive yoke 6, an inductive coil 7, a permanent magnet 8, and an adjustable gap 9.

[0032] Figure 2 The internal space of the pressure-bearing cavity is cylindrical. The side wall of the pressure-bearing cavity is composed of two components of the magnetic conductive pole plate 1 and the non-magnetic cylinder wall 2. The magnetic conductive pole plate 1 provides a magnetic field perpendicular to the central axis of the cylinder for the pressure-sensitive magnetic composite material 3 in the pressure-bearing cavity. The piston component 4 can apply an impact force to the pressure-sensitive magnetic composite material 3 in the cavity along the central axis of the cylinder. The piston component 4 and the non-magnetic base 5 below are both made of non-magnetic materials.

[0033] Figure 3The magnetic circuit structure diagram of the power generation device. Through the connection of the magnetic yoke 6, the pressure-bearing cavity and the induction coil 7 are placed on two parallel branches, and the two parallel branches are provided with magnetic potential by two permanent magnets 8. Since the magnetic permeability of the pressure-sensitive magnetic composite material 3 is much smaller than that of the magnetic core in the induction coil 7, the magnetic flux is mainly concentrated in the induction coil branch, which may cause magnetic saturation of the magnetic core in the induction coil 7, thereby weakening the power generation performance. Therefore, the embodiment is provided with a variable gap 9 in the magnetic circuit, which is used to appropriately increase the magnetic resistance of the induction coil branch, so that the magnetic flux density of the two branches is balanced, and the magnetic saturation phenomenon in the magnetic circuit is avoided.

[0034] The magnetic metal intercompound can be prepared by the following method: first, in a vacuum or a protective atmosphere, the raw materials are smelted into an alloy ingot according to the element ratio of MnCoSi 1- x Ge X (0 < x < 0.25), and the alloy ingot is uniformly heat treated at a temperature of 850-1300 degrees Celsius in an oxygen-free environment for at least 10 minutes, and then slowly cooled to room temperature to obtain the required TiNiSi-type lattice structure. The alloy particles with a particle size of less than 1000 um are prepared by a mechanical crushing method and are annealed at a temperature of 250-500 degrees Celsius to eliminate residual stress in the alloy particles.

[0035] Figure 4 The MnCoSi 0.88 Ge 0.12 Alloy is measured in a 1kOe magnetic field under two pressure conditions of normal pressure and high pressure. The temperature range for measurement is 200 to 345K. The normal pressure is standard atmospheric pressure (0MPa), and the high pressure is 360MPa hydrostatic pressure provided by the sealed cavity of the measuring instrument. Compared with the normal pressure environment, the alloy has higher magnetization under the high pressure environment.

[0036] Figure 5 The MnCoSi 0.88 Ge 0.12 Alloy is measured in a 1kOe magnetic field under two pressure conditions of normal pressure and high pressure. The temperature range for measurement is 200 to 345K. The normal pressure is standard atmospheric pressure (0MPa), and the high pressure is 360MPa hydrostatic pressure provided by the sealed cavity of the measuring instrument. Compared with the normal pressure environment, the alloy has higher magnetization under the high pressure environment.

[0037] The magnetic circuit structure is simulated by using the finite element method, and the relationship between the magnetic flux density in each part of the magnetic circuit and the gap under two pressure conditions is obtained. According to the measured value of the pressure-sensitive magnetic composite material used, the magnetic permeability of the composite material is set to 1.32 under normal pressure and 1.84 under high pressure. With the change from normal pressure to high pressure, the magnetic flux density in the composite material increases, as shown inFigure 6 The magnetic flux density in the coil core decreases, see... Figure 7 That is, the magnetic flux driven by pressure is transferred in the two parallel branches.

[0038] based on Figure 7 The data shown illustrates the relationship between the change in magnetic flux density of various parts of the magnetic circuit in this embodiment under two pressure conditions and the change in gap. Figure 8 As the gap increases, the change in magnetic flux density ΔB in the coil first increases and then decreases. Therefore, in this embodiment, there is an optimal gap value, which is approximately 1.5 mm.

[0039] Figure 9 This invention presents a measured input pressure waveform and a measured output voltage waveform at room temperature, according to an embodiment of the present invention. The measured input pressure waveform is a sine wave with a frequency of 5 Hz and an intensity range of 0-100 MPa. It is generated and controlled by a fatigue testing machine and recorded by a pressure sensor. The measured output pressure waveform is a sine wave of the same frequency and is recorded by a benchtop multimeter.

[0040] Figure 10 This diagram illustrates the measured output voltage waveform versus gap variation at room temperature, according to an embodiment of the present invention. The device achieves the highest voltage output when the air gap is set to 1.5 mm. The measured optimal gap value of 1.5 mm is compared with... Figure 5 The simulation results shown are highly consistent, proving the accuracy of the design simulation and experimental verification of this embodiment. The optimal value of the variable gap is related to the specific dimensions of each component in the magnetic circuit and the magnetic properties of the pressure-sensitive magnetic composite material used.

[0041] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A power generation device using impact energy, characterized by, The application discloses a power generation device for realizing a power generation method, and the power generation method comprises the following steps: driving a magnetic phase change of a pressure-sensitive magnetic composite material by using isotropic pressure change to change the magnetic flux density of the pressure-sensitive magnetic composite material; the pressure-sensitive magnetic composite material comprises a magnetic intermetallic compound Mn-Co-Si-Ge and a solid-state pressure conduction medium; The chemical formula of the magnetic intermetallic compound is MnCoSi 1-x Ge X wherein x has a value ranging from 0 to 0.25, having both antiferromagnetic and ferrimagnetic magnetic states; The initial magnetic permeability and magnetization intensity of the magnetic intermetallic compound under the condition that the pressure is higher than a preset condition are higher than the initial magnetic permeability and magnetization intensity under the condition that the pressure is lower than the preset condition, and the change of the magnetic properties with the pressure condition is reversible; The solid-state pressure conduction medium comprises a main group metal element and an alloy thereof; The solid-state pressure conduction medium comprises paraffin or solid-state grease or a polymer or boron nitride powder; The power generation device is filled with the pressure-sensitive magnetic composite material in a pressure-bearing cavity, and the pressure-sensitive magnetic composite material can be subjected to an impact force in a single axial direction by a piston part; The side wall of the pressure-bearing cavity comprises a magnetic conducting component and a non-magnetic component, wherein the magnetic conducting component serves as a pair of magnetic poles and provides a magnetic field, which is perpendicular to the pressure direction of the outside, for the pressure-sensitive magnetic composite material in the pressure-bearing cavity; The pressure-bearing cavity and a magnetic core, which is wound with an induction coil, are connected in parallel in a magnetic circuit structure to form two branches, and when the magnetic flux of the branch, in which the pressure-bearing cavity is arranged, increases, the magnetic flux in the induction coil decreases; on the contrary, the magnetic flux in the induction coil increases when the magnetic flux of the branch, in which the pressure-bearing cavity is arranged, decreases.

2. The apparatus of claim 1, wherein, An adjustable gap is arranged to adjust the magnetic resistance of the branch, in which the induction coil is arranged, so that the magnetic flux density distribution of the branch, in which the pressure-bearing cavity is arranged, and the branch, in which the induction coil is arranged, is balanced.

3. The apparatus of claim 1, wherein, Permanent magnets are arranged to provide magnetic potential for the two branches.

Images