Multidirectional electromagnetic energy collector

Abstract

The invention belongs to the technical field of electromagnetic energy acquisition systems, and particularly relates to a multi-directional electromagnetic energy acquisition device, which comprises a first electromagnetic energy acquisition device and a plurality of second electromagnetic energy acquisition devices, and the plurality of second electromagnetic energy acquisition devices are arranged around the circumferential direction of the first electromagnetic energy acquisition device at equal intervals. The first electromagnetic energy collector and the second electromagnetic energy collector are vertically arranged in space; the first electromagnetic energy collector is provided with a first floating magnet pile, a first inductance coil and a first movable end, the first movable end is in transmission connection with the first floating magnet pile, and the first floating magnet pile reciprocates to enable induction current to be generated in the first inductance coil; the second electromagnetic energy collector is provided with a second floating magnet pile, a second inductance coil and a second movable end, the second movable end is in transmission connection with the second floating magnet pile, and the second floating magnet pile reciprocates to enable induction current to be generated in the second inductance coil. And the floating magnet stack I is in transmission connection with the floating magnet stack II.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic energy harvesting systems, and in particular relates to a multi-directional electromagnetic energy harvester. Background Art

[0002] With the widespread application of electromagnetic energy harvesters, the common method of collecting energy in a single direction or two-dimensional plane can no longer meet the needs of complex working environments.

[0003] The energy recovery efficiency of existing multi-directional electromagnetic energy harvesters is low. When external excitation occurs, only the single-tube harvester in that direction can effectively collect energy.

[0004] Therefore, providing a new multi-directional electromagnetic energy harvester with high efficiency in collecting energy in multiple directions is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a multi-directional electromagnetic energy harvester to solve the above problems.

[0006] To achieve the above object, the present invention provides the following solutions:

[0007] A multi-directional electromagnetic energy harvester, comprising:

[0008] A first electromagnetic energy harvester and a plurality of second electromagnetic energy harvesters, wherein the plurality of second electromagnetic energy harvesters are arranged around the first electromagnetic energy harvester at equal intervals, and the first electromagnetic energy harvester and the second electromagnetic energy harvester are arranged vertically in space;

[0009] The first electromagnetic energy harvester comprises a floating magnet stack 1, an inductor 1 and a movable end 1, wherein the movable end 1 is transmission-connected to the floating magnet stack 1, and the reciprocating motion of the floating magnet stack 1 generates an induced current in the inductor 1;

[0010] The second electromagnetic energy harvester comprises a second floating magnet stack, a second inductor coil and a second movable end, wherein the second movable end is transmission-connected to the second floating magnet stack, and the reciprocating motion of the second floating magnet stack generates an induced current in the second inductor coil;

[0011] The first floating magnet stack is transmission-connected to the second floating magnet stack;

[0012] When in the first working mode, the movable end 1 is connected to the exciter by transmission, and a plurality of the movable ends 2 are fixed, and the exciter causes the floating magnet stack 1 to reciprocate through the movable end 1 and drives a plurality of the floating magnet stacks 2 to reciprocate to generate an induced current;

[0013] When in the second working mode, any one of the movable ends 2 is connected to the exciter in transmission, and the remaining movable ends 2 and 1 are fixed. The exciter causes the corresponding floating magnet stack 2 to reciprocate through the movable end 2 and drives the remaining several floating magnet stacks 2 and 1 to reciprocate to generate an induced current.

[0014] Optionally, the first electromagnetic energy harvester comprises a shell one, the inductor coil is coaxially sleeved on the outside of the shell one, and the floating magnet stack one is movably arranged in the shell one;

[0015] An adjusting end cover 1 is slidably connected in the shell 1, a permanent magnet 1 is fixedly connected to the end of the adjusting end cover 1, and the permanent magnet 1 is magnetically connected to one end of the floating magnet stack 1.

[0016] Optionally, the floating magnet stack 1 includes a plurality of floating magnets 1, a circular iron sheet 1 is provided between two adjacent floating magnets 1, and two adjacent floating magnets 1 repel each other;

[0017] The magnetic pole direction of the floating magnet one located at an end away from the permanent magnet one is consistent with the magnetic pole direction of the permanent magnet one;

[0018] The floating magnets are provided in an even number.

[0019] Optionally, a magnetic fluid is filled between an inner wall of the shell and an outer wall of the floating magnet.

[0020] Optionally, the thickness of the floating magnet at one end away from the permanent magnet is greater than the thickness of the rest of the floating magnets.

[0021] Optionally, the second electromagnetic energy harvester comprises a second shell, the second inductor coil is sleeved on the outside of the second shell, and the second floating magnet stack is movably arranged in the second shell;

[0022] An adjustable end cover 2 is slidably connected inside the second shell, a permanent magnet 2 is fixedly connected to the end of the second adjustable end cover, and the second permanent magnet is magnetically connected to one end of the second floating magnet stack.

[0023] Optionally, the floating magnet stack 2 includes a plurality of floating magnets 2, a circular iron sheet 2 is provided between two adjacent floating magnets 2, and two adjacent floating magnets 2 repel each other;

[0024] The magnetic pole direction of the floating magnet 2 located at one end away from the permanent magnet 2 is consistent with the magnetic pole direction of the permanent magnet 2;

[0025] The floating magnet 2 located at one end away from the permanent magnet 2 and the floating magnet 1 located at one end away from the permanent magnet 1 are arranged to repel each other;

[0026] The floating magnets 2 are provided in an even number.

[0027] Optionally, magnetic fluid 2 is filled between the second inner wall of the shell and the second outer wall of the floating magnet.

[0028] Compared with the prior art, the present invention has the following advantages and technical effects:

[0029] When in use, the device has two working modes. In the first working mode, the exciter is connected to the active end 1, and the floating magnet stack 1 is driven to reciprocate through the active end 1, and the floating magnet stack 2 is also reciprocated through the transmission connection between the floating magnet stack 1 and each floating magnet stack 2. When the floating magnet stack 1 and the floating magnet stack 2 reciprocate, the magnetic field will cut the corresponding inductor coil 1 and the inductor coil 2 to generate an induced current to achieve energy collection. In the second working mode, the active end 2 in any direction is connected to the exciter transmission to make the corresponding floating magnet stack 2 reciprocate. The reciprocating movement of the floating magnet stack 2 drives the remaining floating magnet stacks 2 and the floating magnet stack 1 to reciprocate and cut the corresponding inductor coil 2 and the inductor coil 1 to generate an induced current to achieve energy collection. Through the above settings, the excitation generated in any direction can cause the first electromagnetic energy collector and each second electromagnetic energy collector to generate an induced current, so as to achieve multi-directional energy collection and improve the collection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor:

[0031] Figure 1 It is a schematic diagram of the structure of the present invention;

[0032] Figure 2 It is a cross-sectional view of the structure of the present invention;

[0033] Among them, 1. One floating magnet stack; 2. One permanent magnet; 3. One circular iron sheet; 4. One inductor; 5. One adjusting end cover; 6. One magnetic fluid; 7. Two magnetic fluids; 8. Two floating magnet stacks; 9. Two inductors; 10. Two adjusting end covers; 11. Two permanent magnets; 12. Two circular iron sheets; 13. One floating magnet; 14. Two floating magnets. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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 are within the scope of protection of the present invention.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0036] Embodiment 1:

[0037] Reference Figure 1 to Figure 2 , this embodiment discloses a multi-directional electromagnetic energy harvester, comprising:

[0038] A first electromagnetic energy harvester and a plurality of second electromagnetic energy harvesters, wherein the plurality of second electromagnetic energy harvesters are arranged around the first electromagnetic energy harvester at equal intervals, and the first electromagnetic energy harvester and the second electromagnetic energy harvester are arranged vertically in space;

[0039] The first electromagnetic energy harvester comprises a floating magnet stack 1, an inductor coil 4 and a movable end 1, wherein the movable end 1 is transmission-connected to the floating magnet stack 1, and the reciprocating motion of the floating magnet stack 1 generates an induced current in the inductor coil 4;

[0040] The second electromagnetic energy collector comprises a floating magnet stack 2 8, an inductor coil 2 9 and a movable end 2, wherein the movable end 2 is transmission-connected to the floating magnet stack 2 8, and the reciprocating motion of the floating magnet stack 2 8 generates an induced current in the inductor coil 2 9;

[0041] The floating magnet stack 1 is transmission-connected to the floating magnet stack 2 8;

[0042] In the first working mode, the movable end 1 is connected to the exciter by transmission, and the plurality of movable ends 2 are fixed. The exciter causes the floating magnet stack 1 to reciprocate through the movable end 1 and drives the plurality of floating magnet stacks 2 8 to reciprocate to generate an induced current.

[0043] When in the second working mode, any active end two is connected to the exciter in transmission, and the remaining active ends two and one are fixed. The exciter causes the corresponding floating magnet stack two 8 to reciprocate through the active end two and drives the remaining floating magnet stacks two 8 and one 1 to reciprocate to generate an induced current.

[0044] When in use, the device has two working modes. In the first working mode, the exciter is connected to the active end 1, and the floating magnet stack 1 is driven to reciprocate through the active end 1, and the floating magnet stack 1 is connected to each floating magnet stack 2 8 through the transmission connection of the floating magnet stack 1 and the floating magnet stack 2 8 to make the floating magnet stack 2 8 also reciprocate. When the floating magnet stack 1 and the floating magnet stack 2 8 reciprocate, the magnetic field will cut the corresponding inductor coil 1 4 and the inductor coil 2 9 to generate an induced current to achieve energy collection. In the second working mode, the active end 2 in any direction is connected to the exciter to make the corresponding floating magnet stack 2 8 reciprocate. The reciprocating movement of the floating magnet stack 2 8 drives the remaining floating magnet stacks 2 8 and the floating magnet stack 1 to reciprocate and cut the corresponding inductor coil 2 9 and the inductor coil 1 4 to generate an induced current to achieve energy collection. Through the above settings, the excitation generated in any direction can make the first electromagnetic energy collector and each second electromagnetic energy collector generate an induced current, so as to achieve multi-directional energy collection and improve the collection efficiency.

[0045] As an optional implementation, the first electromagnetic energy harvester includes a housing 1, an inductor 14 is coaxially sleeved on the outside of the housing 1, and a floating magnet stack 1 is movably arranged in the housing 1;

[0046] An adjusting end cover 15 is slidably connected in the shell 1, and a permanent magnet 2 is fixedly connected to the end of the adjusting end cover 5. The permanent magnet 2 is magnetically connected to one end of the floating magnet stack 1.

[0047] As an optional implementation, the floating magnet stack 1 includes a plurality of floating magnets 13, a circular iron sheet 3 is provided between two adjacent floating magnets 13, and two adjacent floating magnets 13 repel each other;

[0048] The magnetic pole direction of the floating magnet 13 located at one end away from the permanent magnet 2 is consistent with the magnetic pole direction of the permanent magnet 2;

[0049] The floating magnets 13 are provided in an even number.

[0050] As an optional implementation, a magnetic fluid 6 is filled between an inner wall of the shell and an outer wall of the floating magnet 13.

[0051] As an optional implementation, the thickness of the floating magnet 13 located at the end away from the permanent magnet 2 is greater than the thickness of the remaining floating magnets 13.

[0052] As an optional implementation, the second electromagnetic energy harvester includes a second housing, a second inductor coil 9 is sleeved on the outside of the second housing, and a second floating magnet stack 8 is movably arranged in the second housing;

[0053] An adjustable end cover 10 is slidably connected inside the second shell, and a permanent magnet 11 is fixedly connected to the end of the adjustable end cover 10 . The permanent magnet 11 is magnetically connected to one end of the floating magnet stack 8 .

[0054] As an optional embodiment, the floating magnet stack 2 8 includes a plurality of floating magnets 2 14 , a circular iron sheet 2 12 is provided between two adjacent floating magnets 2 14 , and two adjacent floating magnets 2 14 repel each other;

[0055] The magnetic pole direction of the floating magnet 14 located at one end away from the permanent magnet 11 is consistent with the magnetic pole direction of the permanent magnet 11;

[0056] The floating magnet 2 14 located at one end away from the permanent magnet 2 11 and the floating magnet 1 13 located at one end away from the permanent magnet 1 2 are arranged to repel each other;

[0057] The floating magnets 14 are provided in an even number.

[0058] As an optional implementation, a magnetic fluid 7 is filled between the inner wall of the second shell and the outer wall of the second floating magnet 14 .

[0059] Embodiment 2:

[0060] like Figure 1 As shown, the floating magnet 13 of the floating magnet stack 1 and the floating magnet 14 of the floating magnet stack 8 in this embodiment both adopt N35 permanent magnets. The floating magnets 13 of the floating magnet stack 1 are separated by circular iron sheets 3, and the floating magnets 14 of the floating magnet stack 8 are separated by circular iron sheets 12.

[0061] In this embodiment, N35 permanent magnets are selected to form the floating magnet stack 1 or the floating magnet stack 2 8. The number and thickness of the N35 permanent magnets can be adjusted according to the specific energy collection requirements. The inner end faces of the floating magnet stack 1 or the floating magnet stack 2 8 in the channel have the same magnetic poles at the intersection of the channels to ensure coordinated movement under the action of the magnetic field.

[0062] Permanent magnet 1 2 or permanent magnet 2 11 is firmly fixed on the adjustment end cover 1 5 or the adjustment end cover 2 10 by bonding, and the magnetic pole direction of permanent magnet 1 2 is consistent with the magnetic pole direction of the outer end face of floating magnet stack 1, and the magnetic pole direction of permanent magnet 2 11 is consistent with the magnetic pole direction of the outer end face of floating magnet stack 2 8, thereby forming a stable magnetic field structure, providing basic conditions for energy collection.

[0063] The reciprocating motion of the floating magnet stack 1 or the floating magnet stack 2 8 in each channel is affected by the combined force of the magnetic field in each channel. In the Z-axis direction, the force on the magnet stack can be specifically expressed as:

[0064]

[0065] The force on the magnet stack in the XY axis direction can be expressed by the specific formula:

[0066]

[0067] Among them, θ1 represents the instantaneous angle between the horizontal and vertical movers, θ2 represents the instantaneous angle between the horizontal and horizontal movers; m is the mass of the floating magnet stack 1 in the Z-axis direction; F1 and F2 are the resultant forces of the floating magnet 13 and the floating magnet 2 14 indicated by the arrows, and F xz and F xy Both represent the resultant force between two adjacent floating magnet stacks 8 in this direction, F xx represents the resultant force between two floating magnet stacks 8 facing each other in the x direction, wherein the resultant force calculation can be specifically expressed as:

[0068]

[0069] Among them, k>0 is a proportional constant, B1 and B2 are the magnitudes of the two magnetic induction intensities at the force points, and θ is the angle between B1 and B2. It can be seen that when θ≤90°, F>0, an attractive force is generated between the two magnets; when θ>90°, a repulsive force is generated between the two magnets. A single channel in this overall structure can be equivalent to a spring damping vibration system, which is excited by an external vibration collector.

[0070] The working principle of the present invention is:

[0071] Based on the magnetic coupling effect, the floating magnet stack 1 and floating magnet stack 2 8 in each channel reciprocate under the action of the magnetic field force, and the magnetic flux lines cut the inductor coil 1 4 and the inductor coil 2 9 to generate electromotive force, realizing energy collection. The external vibration excites the collector to work, and the force on the floating magnet stack 1 and floating magnet stack 2 8 in each channel affects its movement and energy output.

[0072] Embodiment 3:

[0073] In this embodiment, Ansys Maxwell (19.2) software is used to establish a finite element model of a multi-directional electromagnetic energy harvesting unit. The model is mainly composed of a first electromagnetic energy harvester and a plurality of second electromagnetic energy harvesters, wherein the first electromagnetic energy harvester is composed of a shell 1, a floating magnet stack 1, a permanent magnet 2, a circular iron sheet 3, an inductor coil 4, an adjustment end cover 5 and a magnetic fluid 6.

[0074] The second electromagnetic energy collector is composed of a shell 2, a floating magnet stack 28, a permanent magnet 211, a round iron sheet 212, an inductor 29, an adjustment end cover 210 and a magnetic fluid 27.

[0075] During the model construction process, the material properties and geometric dimensions of each component are precisely set. For example, the circular iron sheet 13, permanent magnet 12, permanent magnet 2 11, floating magnet 13 of floating magnet stack 1 and floating magnet 2 14 of floating magnet stack 2 8 are all selected with a diameter of 10 mm, and floating magnet 13 and floating magnet 2 14 are both made of N35 material and are axially magnetized to simulate the magnetic field distribution in the actual collector.

[0076] Since when the thickness of the circular iron sheet 13 or the circular iron sheet 2 12 is less than 3 mm, the floating magnets 13 or the floating magnets 2 14 arranged in opposite directions on both sides of the circular iron sheet 13 or the circular iron sheet 2 12 cannot be stably assembled together due to the repulsive force, the circular iron sheet 13 or the circular iron sheet 2 12 with a thickness greater than 3 mm is selected for simulation.

[0077] Taking into account the length limitation of the overall channel and the actual thickness of the permanent magnets that can be purchased (such as 3mm and 5mm), in order to facilitate subsequent experimental verification, the simulation work focuses on quantitative calculations of permanent magnets with thicknesses of 3mm and 5mm. At the same time, according to the limitations of the design length of each channel of the collector, the number of permanent magnets 1-2 or permanent magnets 2-11 can be selected as 2 or 4 for simulation calculations, so as to comprehensively analyze the energy output characteristics under different magnet arrangement quantity and size combinations.

[0078] In order to further study the relationship between the arrangement of magnets and the generation of electromotive force, the present invention simulates a variety of different magnet arrangements. By comparing the arrangement of magnetic poles in the same direction and in the opposite direction, it is found that the magnetic induction intensity of magnetic poles arranged in the opposite direction has a greater difference. Taking the first electromagnetic energy harvester as an example, the magnetic flux density at the intersection of permanent magnet 2 and circular iron sheet 3 is relatively higher. According to the electromagnetic induction energy output relationship:

[0079] ,

[0080] In the formula is the induced electromotive force, is the magnitude of the magnetic flux passing through the closed loop, N is the number of coil turns, is the flux linkage, which is equal to the magnetic flux passing through each turn of the inductor coil. The relationship is . It can be seen that when the arrangement is in the opposite direction The value of is larger, so the reverse arrangement can output higher energy.

[0081] Finite element simulation was performed under the conditions of frequency 15Hz, radius of inductor coil 4 6.5mm, and width of inductor coil 4 35mm. The results showed that the peak current generated by the same direction arrangement of the magnets in floating magnet stack 1 was 4.2mA, and the peak current generated by the reverse direction arrangement was 7.3mA. Therefore, it was determined that the subsequent models of floating magnet stack 1 and floating magnet stack 28 in this article all adopted the reverse direction arrangement structure to improve the energy collection efficiency.

[0082] Specifically, according to the overall size requirements of the collector, the number of the floating magnets 13 of the floating magnet stack 1 can be set to 2 or 4.

[0083] The energy output of floating magnets 13 of different thicknesses (3mm and 5mm) at different spacings (the thickness of the circular iron sheet 3 increases from 3mm to 6mm) is analyzed in detail. The comparison results show that when the thickness of the circular iron sheet 3 increases, the energy peak value generated by the floating magnet stack 1 composed of floating magnets 13 with a thickness of 5mm is higher than that of the floating magnet stack 1 composed of floating magnets 13 with a thickness of 3mm.

[0084] Further simulation calculations were performed on the floating magnet stack-1 composed of 2 and 4 5mm floating magnets-13. The results showed that both of the two floating magnet stacks-1 output the highest current when the thickness of the circular iron sheet-3 is 5mm.

[0085] Finally, the energy output capacity is compared when the number of floating magnets 13 in the floating magnet stack 1 is 2 and 4. After comprehensive consideration, it is determined that the floating magnet stack 1 and floating magnet stack 2 8 composed of four floating magnets 13 and two floating magnets 2 14 are used in the Z-axis channel and the XY-axis channel respectively, and the thickness of the circular iron sheet 1 3 and the circular iron sheet 2 12 is set to 5 mm to achieve the best energy output effect.

[0086] Specifically, the multi-directional electromagnetic energy harvester designed by the present invention needs to work stably under external excitation in all directions, which requires that the floating magnet stack 1 in each channel has a suitable equilibrium position in static state, and has sufficient restoring force to support its reciprocating motion in the extreme working position under working conditions. For the floating magnet stack 8 and the floating magnet stack 1, the force variation law of the floating magnet stack 1 in the Z-axis direction is analyzed by simulation under nine conditions of spacing L=26mm, 30mm and 34mm, and Z-axis channel height H=60mm, 63mm and 66mm. The results show that under the same L condition, the force of the floating magnet stack 1 increases with the increase of the height adjustment of the adjustment end cap 5; under the same height of the permanent magnet 2, the force of the floating magnet stack 1 increases with the decrease of the horizontal spacing. For example, when L=26mm, as H increases from 60mm to 66mm, the force of the floating magnet stack 1 in the Z-axis direction gradually increases. The data with the best force in each group were selected for further comparison with the mass of the vertical floating magnet stack 1 itself. It was found that after the floating magnet stack 1 overcame its own gravity in the Z-axis direction, the force direction was downward within the movement range of 0-2.5mm, which may cause the floating magnet stack 1 to be unstable during movement.

[0087] In order to solve the above problem, the thickness of the permanent magnet 2 at the intersection of the floating magnet stack 1 is changed. When the thickness of the floating magnet 13 at the end of the floating magnet stack 1 in the Z axis is increased to 10 mm, the force variation law of the floating magnet stack 1 in the Z axis direction is compared again in the above manner.

[0088] Through a large number of simulation calculations and comparative analysis, it is found that the optimal data is obtained when the horizontal spacing L=26mm and the height of the end cap 5 is adjusted to H=66mm. At this time, the force on the floating magnet stack 1 in the Z-axis direction is significantly increased, and the force on the lower part of the channel is upward, which ensures that the floating magnet stack 1 in the Z-axis channel is always suspended in the pipeline, and can produce more sensitive feedback to external excitation, effectively improving the stability of the collector's energy output. For example, compared with the end magnet thickness of 5mm, under the same excitation conditions, the floating magnet stack 1 with an end magnet thickness of 10mm has more stable movement in the Z-axis direction and smaller energy output fluctuations.

[0089] Specifically, the energy output of floating magnet stacks 1 with different thicknesses (3mm and 5mm) at different spacings (the thickness of the circular iron sheet 3 increases from 3mm to 6mm) is analyzed in detail. The comparison results show that when the thickness of the circular iron sheet 3 increases, the energy peak value generated by the floating magnet stack 1 composed of the floating magnet 13 with a thickness of 5mm is higher than that of the floating magnet stack 1 composed of the floating magnet 13 with a thickness of 3mm.

[0090] Further simulation calculations were performed on the floating magnet stack 1 consisting of two and four floating magnets 13 with a thickness of 5 mm. The results showed that both of the two floating magnet stacks 1 output the highest current when the thickness of the circular iron sheet 3 is 5 mm.

[0091] Finally, the energy output capacity is compared when the number of floating magnets 13 in the floating magnet stack 1 is 2 and 4. After comprehensive consideration, it is determined that four floating magnets 13 and two floating magnets 2 14 are used in the Z-axis channel and the XY-axis channel to form the floating magnet stack 1 and the floating magnet stack 2 8, respectively, and the thickness of the circular iron sheet 1 3 and the circular iron sheet 2 12 is set to 5 mm to achieve the best energy output effect.

[0092] Specifically, the diameter (dc) of the enameled wire of the inductor coil 1 4 and the inductor coil 2 9, the number of coil layers (n) and the winding width (W) of the inductor coil 1 4 are important parameters affecting the energy output, which determine the total length (l) and total resistance of the enameled wire used. It can be expressed by the specific formula:

[0093]

[0094]

[0095] Among them, W coil Expressed as the width of the winding coil, is the resistivity of the enameled wire, s is the cross-sectional area of ​​the enameled wire, n is the number of coil layers, dc is the diameter of the enameled wire, and D tu is the winding coil diameter.

[0096] Specifically, the total length of the enameled wire and the total resistance of the wound inductor coil 1 4 or inductor coil 2 9 can be calculated by two formulas. In this study, in order to achieve the maximum output power, the inductor coil 1 4 and inductor coil 2 9 are optimized and designed according to the magnetic field distribution of the floating magnet stack 1 and the floating magnet stack 2 8. The winding position of the inductor coil 1 4 and the inductor coil 2 9 should cover the part with the largest magnetic flux density as much as possible, because only in this way can the magnetic flux change be maximized when the floating magnet stack 1 and the floating magnet stack 2 8 move, thereby generating a larger current.

[0097] Specifically, according to the magnetic induction cloud map, two winding methods were designed for the floating magnet stack 8 in the XY axis direction, and the finite element simulation was used to calculate the coil widths W1 and W2 in increasing order from 5 mm. Comparing the output currents of the two winding methods, it was found that the output electrical signal was disordered under the W2 winding method and the output maximum value was significantly lower than that of the W1 winding method. This is because when the floating magnet stack 8 passes the equilibrium position, the output electrical signal is disordered due to the different magnetic flux densities on the same side of the two inductor coils 9. Therefore, it is determined to adopt the W1 winding method in the XY axis direction. Further analysis of the output current of different coil widths under the W1 winding method found that as the width of the inductor coil 9 increases, the output current peak shows a certain change pattern. By comprehensively considering factors such as energy output efficiency and coil volume, the optimal winding width of the inductor coil 9 in the XY axis direction in this work is determined.

[0098] Specifically, for the inductor coil 4 on the Z-axis channel, the corresponding winding method is designed, and the output current of the inductor coil 4 with different widths is calculated. The results show that when the coil width of the inductor coil 4 increases from 5mm to 9mm, the output current peak increases with the increase of the width. After comprehensive consideration, it is determined that the windings of the inductor coil 4 of the Z-axis channel in this work are all located opposite to the center line of the circular iron sheet 3, and the winding width is 9mm to achieve the best energy collection effect.

[0099] Embodiment 4:

[0100] This embodiment manufactures a prototype of a new multi-directional electromagnetic energy harvester based on the collector-related parameters obtained by the above simulation optimization. The geometric parameters of the prototype are precisely designed. For example, the XY axis channel length is determined to be 41mm, the Z axis channel length is 66mm, the width of the inductor coil 29 is 9mm, the width of the inductor coil 14 is 9mm, the outer diameter of the channel is 11mm, the inner diameter of the channel is 10.2mm, the diameter of the enameled wire is 0.2mm, etc., and there are 3 inductor coils 14. During the processing and manufacturing process, appropriate materials and processing techniques are selected in strict accordance with the design requirements to ensure the dimensional accuracy and assembly accuracy of each component. For example, for the assembly of the floating magnet stack 1 and the floating magnet stack 28, it is necessary to ensure that the floating magnet 13 and the circular iron sheet 13, the floating magnet 2 14 and the circular iron sheet 2 12 are alternately arranged closely and the magnetic pole direction is correct; for the winding of the inductor coil 14 and the inductor coil 29, it is necessary to ensure that the width and position of the inductor coil 14 and the inductor coil 29 meet the design requirements to ensure that the collector can accurately reflect the performance characteristics of the design scheme.

[0101] Specifically, the experimental platform is mainly composed of an exciter, a signal generator, a power amplifier, a data acquisition module, a piezoelectric accelerometer, a dynamic signal detection analyzer and two computers. The exciter is used as a vibration excitation source. Its movement is controlled by the signal generated by the signal generator after being amplified by the power amplifier, and it can generate vibrations of different frequencies and accelerations. The piezoelectric accelerometer is used to detect the vibration acceleration of the exciter, and its output signal is transmitted to the data acquisition module. The data acquisition module transmits the collected acceleration signal and the electrical signal output by the collector to the dynamic signal detection analyzer for analysis and processing. The two computers are used to control the signal generator to generate excitation signals and record and analyze the experimental data output by the dynamic signal detection analyzer. The devices are connected by data cables or signal cables to ensure accurate and reliable signal transmission, so that the performance of the collector under different working conditions can be comprehensively and accurately evaluated.

[0102] In order to measure the acquisition frequency band of the collector, vibration experiments in the vertical and XY axis directions were carried out respectively.

[0103] Specifically, the Z-axis vibration experiment requires the exciter to be placed vertically so that the plane of the excitation table reciprocates along the Z axis. During the experiment, the excitation frequency was swept from 5Hz to 15Hz, the step size was set to 1Hz, the acceleration was set to 0.2g, 0.3g and 0.4g respectively, and the application time of each excitation condition was 2s. By precisely controlling these experimental parameters, the energy output characteristics of the collector under different excitation conditions can be fully studied.

[0104] The experimental results show that when the collector vibrates along the Z-axis direction, the energy output waveform of the floating magnet stack-1 in the XY-axis channel is consistent with the waveform corresponding to the Z-axis direction. This shows that when the collector is excited in the Z-axis direction, it can achieve multi-directional energy output, verifying the effectiveness of the multi-directional energy collection of the present invention. For example, when the excitation frequency is 11Hz and the acceleration is 0.3g, the output waveforms of the Z-axis channel and the XY-axis channel have a certain correlation in phase and amplitude, indicating the synergy in the multi-directional energy collection process.

[0105] Specifically, in order to obtain the optimal output power of the multi-directional electromagnetic energy harvester, the windings on the Z-axis channel are connected in series in a range of 5 to 15. The load resistance is 1 to 10 in series with the windings on the XY axis channels. The load resistance is set to 1000, and the voltage value provided by the collector to each load resistance is measured under the excitation condition of the best energy output of each channel. The specific calculation method of the average power output of the collector is:

[0106]

[0107] In the formula is the average output power, is the RMS value of the measured voltage, and its relationship with the measured peak-to-peak voltage value can be expressed as , It represents the resistance of the load resistor in series during measurement. Therefore, the average output power can be directly calculated as:

[0108]

[0109] The average power density of the electromagnetic energy harvester can also be calculated as follows:

[0110]

[0111] Where P D Indicates power density, Represents the average power of each sinusoidal voltage, T i Represents the period of each sinusoidal voltage, V tol Represents the total volume of the collector. The experiment found that when the load resistance is less than the internal resistance of the winding, the measured voltage maintains a high growth rate as the load resistance increases, and when the load resistance is greater than the internal resistance of the winding, the growth rate of the measured voltage slows down; the calculated output power reaches the maximum value when the load resistance is equal to the internal resistance of the winding, and the maximum power generated by the vertical and XY axis channels is 1.73mW and 0.6mW respectively. Therefore, the maximum total power generated by the five channels of the collector can reach 4.13mW, and the output power density is 0.198mW / cm³. These data provide an important basis for evaluating the energy conversion efficiency and performance of the collector, and also provide a reference for further optimizing the design of the collector.

[0112] The XY axis vibration experiment requires the exciter to be placed horizontally and the vibration table to reciprocate along the X axis. Since the four horizontal channels are placed opposite to each other, the experiment is replaced by only one scheme, which is vibration along the X axis. In the experiment, different excitation frequencies and accelerations are also set to study the energy output characteristics of the collector when it is excited in the XY axis direction.

[0113] The experimental results show that when the collector vibrates along the X-axis direction, when the excitation frequency does not exceed 11Hz, the energy output waveform of the floating magnet stack 28 in the XY-axis channel is similar to that of the Z-axis channel, indicating that under low-frequency excitation, the energy collection performance of the collector in multiple directions is relatively stable. However, when the excitation frequency exceeds 11Hz, the voltage output by the collector of the Z-axis channel drops sharply, and even approaches no signal output. This is because as the vibration frequency in the X-direction continues to increase, the collision pressure between the floating magnet stack 1 in the Z-axis channel and the tube wall increases, thereby increasing the friction between the floating magnet stack 1 and the tube wall; when the frequency reaches a certain value, the friction will be equal to or greater than the deadweight of the mover magnet stack, hindering the magnet stack from vibrating up and down along the Z-axis direction, causing the generated energy to drop sharply or even approach zero. For example, when the excitation frequency is 15Hz and the acceleration is 0.6g, the output voltage of the Z-axis channel is significantly lower than the output voltage during low-frequency excitation, and the output waveform of the XY-axis channel also changes to a certain extent, which further illustrates the complex performance of the collector under different frequency excitations.

[0114] By connecting different load resistors in series to each channel winding, the output voltage of the harvester is measured and the power is calculated. The results show that when the load resistance is less than the internal resistance of the winding, the measured voltage maintains a high growth rate as the load resistance increases. When the load resistance is equal to the internal resistance of the winding, the output power reaches the maximum value. The maximum power generated by the XY axis and Z axis channels are 0.85mW and 0.185mW respectively. Therefore, the maximum total power generated by the energy harvester can reach 3.585mW, and the output power density is 0.172mW / cm 3 .

[0115] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0116] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A multi-directional electromagnetic energy harvester, characterized in that: include: A first electromagnetic energy harvester and a plurality of second electromagnetic energy harvesters, wherein the plurality of second electromagnetic energy harvesters are arranged around the first electromagnetic energy harvester at equal intervals, and the first electromagnetic energy harvester and the second electromagnetic energy harvester are arranged vertically in space; The first electromagnetic energy harvester comprises a floating magnet stack (1), an inductor coil (4) and a movable end (1), wherein the movable end (1) is in transmission connection with the floating magnet stack (1), and the reciprocating motion of the floating magnet stack (1) generates an induced current in the inductor coil (4); The second electromagnetic energy harvester comprises a second floating magnet stack (8), a second inductor coil (9) and a second movable end, wherein the second movable end is transmission-connected to the second floating magnet stack (8), and the reciprocating motion of the second floating magnet stack (8) generates an induced current in the second inductor coil (9); The floating magnet stack 1 (1) is transmission-connected to the floating magnet stack 2 (8); When in the first working mode, the movable end 1 is connected to the exciter in a transmission manner, and a plurality of the movable ends 2 are fixed. The exciter causes the floating magnet stack 1 (1) to reciprocate through the movable end 1 and drives a plurality of the floating magnet stacks 2 (8) to reciprocate to generate an induced current. When in the second working mode, any one of the movable ends 2 is connected to the exciter in a transmission manner, and the remaining movable ends 2 and 1 are fixed. The exciter causes the corresponding floating magnet stack 2 (8) to reciprocate through the movable end 2 and drives the remaining plurality of floating magnet stacks 2 (8) and the floating magnet stack 1 (1) to reciprocate to generate an induced current.

2. A multi-directional electromagnetic energy harvester according to claim 1, characterized in that: The first electromagnetic energy harvester comprises a shell one, the inductor coil one (4) is coaxially sleeved on the outside of the shell one, and the floating magnet stack one (1) is movably arranged in the shell one; An adjustable end cover (5) is slidably connected inside the housing, a permanent magnet (2) is fixedly connected to the end of the adjustable end cover (5), and the permanent magnet (2) is magnetically connected to one end of the floating magnet stack (1).

3. A multi-directional electromagnetic energy harvester according to claim 2, characterized in that: The floating magnet stack (1) comprises a plurality of floating magnets (13), a circular iron sheet (3) is provided between two adjacent floating magnets (13), and the two adjacent floating magnets (13) repel each other; The magnetic pole direction of the floating magnet 1 (13) located at one end away from the permanent magnet 1 (2) is consistent with the magnetic pole direction of the permanent magnet 1 (2); The floating magnets (13) are provided in even number.

4. A multi-directional electromagnetic energy harvester according to claim 3, characterized in that: A magnetic fluid (6) is filled between the inner wall of the shell and the outer wall of the floating magnet (13).

5. The multi-directional electromagnetic energy harvester according to claim 3, characterized in that: The thickness of the floating magnet one (13) located at one end away from the permanent magnet one (2) is greater than the thickness of the remaining floating magnets one (13).

6. The multi-directional electromagnetic energy harvester according to claim 3, characterized in that: The second electromagnetic energy harvester comprises a second shell, the second inductor coil (9) is sleeved on the outside of the second shell, and the second floating magnet stack (8) is movably arranged in the second shell; An adjustable end cover 2 (10) is slidably connected inside the second shell, and a permanent magnet 2 (11) is fixedly connected to the end of the second adjustable end cover (10), and the second permanent magnet (11) is magnetically connected to one end of the second floating magnet stack (8).

7. The multi-directional electromagnetic energy harvester according to claim 6, characterized in that: The floating magnet stack 2 (8) comprises a plurality of floating magnets 2 (14), a circular iron sheet 2 (12) is provided between two adjacent floating magnets 2 (14), and the two adjacent floating magnets 2 (14) repel each other; The magnetic pole direction of the second floating magnet (14) located at one end away from the second permanent magnet (11) is consistent with the magnetic pole direction of the second permanent magnet (11); The floating magnet 2 (14) located at one end away from the permanent magnet 2 (11) and the floating magnet 1 (13) located at one end away from the permanent magnet 1 (2) are arranged to repel each other; The floating magnets 2 (14) are provided in an even number.

8. The multi-directional electromagnetic energy harvester according to claim 7, characterized in that: A magnetic fluid 2 (7) is filled between the inner wall of the second shell and the outer wall of the second floating magnet (14).

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