Method and device for generating power by utilizing impact energy

Abstract

The invention discloses a method and a device for generating power by using impact energy, and the method comprises the steps: driving the magnetic phase change of a pressure-sensitive magnetic composite material by using isotropic pressure intensity change, so that the magnetic flux density of the pressure-sensitive magnetic composite material is changed; the pressure-sensitive magnetic composite material comprises a magnetic intermetallic compound Mn-Co-Si-Ge and a solid pressure conduction medium. According to the invention, the impact force in the uniaxial direction is converted into isotropic pressure change by utilizing a solid pressure conduction medium, so that the Mn-Co-Si-Ge alloy particle has no special requirement on the mechanical strength and has the advantage of high bearing capacity; and the used Mn-Co-Si-Ge alloy is a transition intermetallic compound, so that the material cost is relatively low.

Description

Technical Field

[0001] The invention belongs to the technical field of power generation, and in particular relates to a method and device for generating power using impact energy. Background Art

[0002] When stamping machines, pile drivers, freight locomotives, trucks and other equipment are in operation, they will generate strong impact forces on their components, bases and the ground. These energies are transmitted in the form of mechanical vibrations, generating strong noises, and are converted into heat energy and dissipated into the surrounding environment. The above-mentioned equipment often uses thicker and heavier structural parts to cope with the strong impact during operation. If the above-mentioned impact energy can be recovered to a certain extent and converted into electrical energy output, it will not only produce some vibration reduction and noise reduction effects, alleviate the potential damage of the impact force to various components, but also help to make the equipment lighter and more compact. In addition, the voltage or current converted from the vibration energy can also be used as a vibration sensing signal to monitor the operating status of the equipment.

[0003] Impact energy has the characteristics of short motion stroke, short action time and high instantaneous force value. Traditional power generation devices are based on the motion-induced electromotive force generated by the relative motion of the induction coil in the magnetic field, which requires the driving force to generate a large motion stroke, so it is difficult to directly use it to collect impact energy. At present, there are several common technical solutions for pressure power generation. One is to use mechanical structures such as levers and gears to amplify the displacement of the induction coil relative to the magnetic field, and realize the output of voltage based on the principle of motion-induced electromotive force. Due to the inertia of the motion mechanism itself, this type of device has a slow response speed to instantaneous forces and low efficiency in conducting impact energy. Another technical solution for pressure power generation is based on the piezoelectric effect of materials such as ceramics and polymers. Although this solution does not rely on the motion stroke, the mechanical bearing capacity of piezoelectric materials is relatively low, and there is a high probability of damage under the action of instantaneous strong impact. In addition, pressure power generation can also be achieved based on the property that the magnetocrystalline anisotropy coefficient of magnetostrictive materials changes with uniaxial pressure. However, common magnetostrictive alloys such as Td-Dy-Fe alloys and Fe-Ga alloys not only contain a large amount of high-priced metal elements, but their performance is highly dependent on the specific grain arrangement. Therefore, the preparation cost of the material is relatively high, which limits its application prospects. Summary of the invention

[0004] In view of this, the present invention provides a method for generating electricity using impact energy, which uses isotropic pressure changes to drive the magnetic phase change of a pressure-sensitive magnetic composite material to change its magnetic flux density; the pressure-sensitive magnetic composite material includes a magnetic intermetallic compound Mn-Co-Si-Ge and a solid pressure conductive medium.

[0005] Preferably, the chemical formula of the magnetic intermetallic compound is MnCoSi 1-x Ge X, where the value of x ranges from 0 to 0.25, and it has two magnetic states: antiferromagnetic and ferrimagnetic.

[0006] Preferably, the initial magnetic permeability and magnetization intensity of the magnetic intermetallic compound under a pressure higher than a preset condition are higher than the initial magnetic permeability and magnetization intensity under a pressure lower than the preset condition, and the change of the magnetic property with the pressure condition is reversible.

[0007] Preferably, the solid pressure conducting medium comprises main group metal single substances such as indium, tin or aluminum and alloys thereof.

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

[0009] Based on the above purpose, the present invention also provides a power generation device utilizing impact energy, which is a power generation device for realizing the above power generation method. The power generation device loads a pressure-sensitive magnetic composite material into a pressure-bearing cavity, and a piston component can apply a uniaxial impact force to it.

[0010] Preferably, the side wall of the pressure-bearing cavity includes a magnetic conductive component and a non-magnetic component, wherein the magnetic conductive component acts 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 wound with an induction coil are connected in parallel on the magnetic circuit structure to form two branches. When the magnetic flux of the branch where the pressure-bearing cavity is located increases, the magnetic flux in the induction coil decreases accordingly, and vice versa.

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

[0013] Preferably, permanent magnets are used to provide magnetomotive force for the two branches.

[0014] The power generation process of the device is as follows. Under normal pressure conditions, the magnetic permeability and saturation magnetization of the magnetic intermetallic compound are relatively low, and the magnetic resistance of the pressure cavity is large, so most of the magnetic flux flows through the induction coil branch; under high pressure conditions, the magnetic permeability and saturation magnetization of the magnetic intermetallic compound are relatively high, and the magnetic resistance of the pressure cavity is low, so part of the magnetic flux is transferred from the induction coil branch to the branch where the pressure cavity is located. It can be seen that under the action of the impact force, that is, the rapid application and removal of external pressure, the magnetic flux in the induction coil also decreases and increases rapidly, and then a set of voltage pulses are output to realize the conversion of impact energy into electrical energy.

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

[0016] The present invention adopts a solid material with certain fluidity, ductility or deformation ability under pressure as a pressure transmission medium, which can transform the axial impact force applied by the piston device into a uniformly distributed pressure change and transmit it to the alloy particles from all directions.

[0017] The pressure-sensitive magnetic material and the induction coil of the present invention are respectively located in two magnetic flux branches connected in parallel with each other. The change of external pressure drives the transfer of magnetic flux in the two branches to realize the change of magnetic flux in the induction coil. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0019] Figure 1 This is a schematic diagram of the structure of a device for generating electricity using impact energy according to an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of the pressure chamber structure of the device for generating electricity using impact energy according to an embodiment of the present invention;

[0021] Figure 3 A schematic diagram of the magnetic circuit structure of a device for generating electricity using impact energy according to an embodiment of the present invention;

[0022] Figure 4 The magnetic intermetallic compound MnCoSi is used for the power generation device using impact energy in the embodiment of the present invention. 0.88 Ge 0.12 Curves showing the change of magnetization intensity M with temperature T in 1kOe magnetic field and under normal pressure and high pressure conditions;

[0023] Figure 5 The magnetic intermetallic compound MnCoSi is used for the power generation device using impact energy in the embodiment of the present invention. 0.88 Ge 0.12 Magnetization curves under normal and high pressure conditions and at a temperature of 280K;

[0024] Figure 6 A graph showing the relationship between the magnetic flux density B in a pressure-sensitive magnetic composite material according to an embodiment of the present invention and the gap under two pressure conditions, obtained by simulating the magnetic circuit using the finite element method;

[0025] Figure 7The relationship diagram of the magnetic flux density B in the magnetic core of the induction coil of one embodiment of the present invention under two pressure conditions with the gap is obtained by simulating the magnetic circuit using the finite element method;

[0026] Figure 8 A graph showing the relationship between the change in magnetic flux density ΔB in the magnetic core of an induction coil of an embodiment of the present invention under two pressure conditions and the change in the gap, obtained by simulating the magnetic circuit using the finite element method;

[0027] Fig. 9 1 is a waveform of a measured input pressure P and a waveform of a measured output voltage V according to an embodiment of the present invention;

[0028] Fig.10 is the measured output voltage peak value V of an embodiment of the present invention peak Graph showing the relationship between the gap and the DETAILED DESCRIPTION

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

[0030] The present invention provides a method for generating electricity using impact energy, which uses isotropic pressure changes to drive the magnetic phase change of a pressure-sensitive magnetic composite material to change its magnetic flux density; the pressure-sensitive magnetic composite material includes a magnetic intermetallic compound Mn-Co-Si-Ge and a solid pressure conductive medium.

[0031] See also Figure 1-3 , which is a schematic diagram of the structure of the device, and the reference numerals are as follows: magnetic pole plate 1, non-magnetic cylinder wall 2, pressure-sensitive magnetic composite material 3, piston component 4, non-magnetic base 5, magnetic yoke 6, induction coil 7, permanent magnet 8, adjustable gap 9.

[0032] Figure 2 The internal space of the middle pressure-bearing cavity is cylindrical. The side wall of the pressure-bearing cavity is composed of components of two materials: a magnetic pole plate 1 and a non-magnetic cylinder wall 2. The magnetic 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 exert an impact force on 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 3It is a magnetic circuit structure diagram of a power generation device. Through the connection of the magnetic yoke iron 6, the pressure-bearing cavity and the induction coil 7 are placed on two parallel branches, and two permanent magnets 8 provide magnetic potential for the two parallel branches. 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 in the magnetic core of the induction coil 7 and weaken the power generation performance. Therefore, in this embodiment, a variable gap 9 is provided in the magnetic circuit to appropriately increase the magnetic resistance of the induction coil branch, so that the magnetic flux densities of the two branches are roughly balanced and magnetic saturation in the magnetic circuit is avoided.

[0034] The magnetic intermetallic compound can be prepared by the following method: First, in a vacuum or protective atmosphere, according to the element ratio of MnCoSi 1- x Ge X (0 < x < 0.25), the raw materials are melted into an alloy ingot. The alloy ingot is homogenized and heat-treated at a temperature of 850 - 1300 °C 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 less than 1000 μm are prepared by mechanical crushing and annealed at a temperature of 250 - 500 °C to eliminate the residual stress in the alloy particles.

[0035] Figure 4 For the MnCoSi 0.88 Ge 0.12 alloy adopted in an embodiment of the present invention, the magnetization intensity change curve measured under two pressure conditions of normal pressure and high pressure in a 1 kOe magnetic field is shown. The measured temperature range is 200 to 345 K. The normal pressure is the standard atmospheric pressure (0 MPa), and the high pressure is the 360 MPa isostatic pressure provided by the closed cavity of the measuring instrument. Compared with the normal pressure environment, the alloy has a higher magnetization intensity in the high pressure environment.

[0036] Figure 5 For MnCoSi 0.88 Ge 0.12 alloy, the magnetization curve measured under two pressure conditions of normal pressure and high pressure at a temperature of 280 K is shown. The normal pressure is the standard atmospheric pressure, and the high pressure is the 360 MPa isostatic pressure. Compared with the normal pressure environment, the alloy has a higher initial magnetic permeability and magnetization intensity in the high pressure environment.

[0037] Using the finite element method to simulate the magnetic circuit structure, the variation relationship of the magnetic flux density in each part of the magnetic circuit with the gap under two pressure conditions can be obtained. Referring to the measured values of the pressure-sensitive magnetic composite material used, the magnetic permeability of this composite material is set to 1.32 under normal pressure and 1.84 under high pressure in the simulation. As the pressure changes from normal pressure to high pressure, the magnetic flux density in the composite material increases, as shown in Figure 6 The magnetic flux density in the coil core is reduced, see Figure 7 That is, the pressure-driven magnetic flux is transferred between the two parallel branches.

[0038] based on Figure 7 The data shown in FIG. 1 show the relationship between the change in the magnetic flux density of each part of the magnetic circuit of this embodiment under two pressure conditions and the change in the gap, as shown in FIG. Figure 8 As the gap increases, the change in magnetic flux density ΔB in the coil increases first and then decreases. Therefore, the gap in this embodiment has an optimal value, which is about 1.5 mm.

[0039] Fig. 9 The measured input pressure waveform and the measured output voltage waveform at room temperature of an embodiment of the present invention are shown. The measured input pressure waveform is a sine wave with a frequency of 5 Hz and an intensity variation range of 0-100 MPa, which is generated and controlled by a fatigue testing machine and recorded by a pressure sensor. The measured output pressure waveform is a sine wave with the same frequency, which is recorded by a desktop multimeter.

[0040] Fig.10 The measured output voltage waveform of an embodiment of the present invention at room temperature varies with the gap. When the gap is set to 1.5 mm, the device can obtain the highest voltage output. The measured optimal gap value of 1.5 mm is Figure 5 The simulation results shown are highly consistent, proving the accuracy of the design simulation and actual measurement verification of this embodiment. The size of the optimal value of the variable gap is related to the specific size of each component in the magnetic circuit and the magnetic properties of the pressure-sensitive magnetic composite material used.

[0041] The above are only 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 in the protection scope of the present invention.

Claims

1. A method for generating electricity using impact energy, characterized in that: The isotropic pressure change is used to drive the magnetic phase change of the pressure-sensitive magnetic composite material, so that its magnetic flux density changes; the pressure-sensitive magnetic composite material includes a magnetic intermetallic compound Mn-Co-Si-Ge and a solid pressure conductive medium.

2. The method according to claim 1, characterized in that The chemical formula of the magnetic intermetallic compound is MnCoSi 1-x Ge X , where the value of x ranges from 0 to 0.25, and it has two magnetic states: antiferromagnetic and ferrimagnetic.

3. The method according to claim 1, characterized in that The initial magnetic permeability and magnetization intensity of the magnetic intermetallic compound under a pressure higher than a preset condition are higher than the initial magnetic permeability and magnetization intensity under a pressure lower than the preset condition, and the change of the magnetic property with the pressure condition is reversible.

4. The method according to claim 1, characterized in that: The solid pressure conducting medium includes main group metal elements and alloys thereof.

5. The method according to claim 1, characterized in that The solid pressure transfer medium includes paraffin or solid grease or polymer or boron nitride powder.

6. A device for generating electricity using impact energy, characterized in that: The invention is a power generation device for realizing the power generation method described in any one of claims 1 to 5. The power generation device is a device for filling a pressure-sensitive magnetic composite material into a pressure-bearing cavity, and a piston component can apply a uniaxial impact force to the pressure-sensitive magnetic composite material.

7. The device according to claim 6, characterized in that The side wall of the pressure-bearing cavity includes a magnetic conductive component and a non-magnetic component, wherein the magnetic conductive component acts 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.

8. The device according to claim 6, characterized in that The pressure-bearing cavity and a magnetic core wound with an induction coil are connected in parallel on the magnetic circuit structure to form two branches. When the magnetic flux of the branch where the pressure-bearing cavity is located increases, the magnetic flux in the induction coil decreases accordingly, and vice versa.

9. The device according to claim 8, characterized in that An adjustable gap is provided to adjust the magnetic resistance of the branch where the induction coil is located, so that the magnetic flux density distribution of the branch where the pressure-bearing cavity is located and the branch where the induction coil is located is balanced.

10. The device according to claim 8, characterized in that Permanent magnets are used to provide magnetic flux potential for the two branches.

Images