CN101944821B - Permanent-magnet damping linear generator - Google Patents

Abstract

The invention discloses a permanent magnet damping linear power generation device, which comprises a casing, end covers at both ends of the casing, a mover and a stator arranged in the cavity of the casing; the stator includes a cylindrical The winding bracket and the windings wound on the outside of the winding bracket, there is a wire lead-out groove between the winding bracket and the casing, the casing is provided with a wire lead-out port, and the wire lead-out port communicates with the wire lead-out groove; the mover is coaxial with the casing cylinder, including several axially magnetized mover permanent magnets and an iron core located between two adjacent mover permanent magnets. The magnetization direction of the adjacent two mover permanent magnets is opposite. The mover permanent magnet and the core diameter equal; the inner side of the end cover is provided with a fixed permanent magnet, and the magnetization direction of the fixed permanent magnet is opposite to that of the mover permanent magnet near the end of the fixed permanent magnet. The permanent magnet damping linear power generation device of the present invention has the advantages of simple structure, high induced electromotive force and low production cost.

Description

A permanent magnet damping linear power generation device

technical field

The invention relates to the technical field of small power generation equipment, in particular to a permanent magnet damping linear power generation device.

Background technique

In some specific industrial occasions, due to the requirements of the working environment, wireless sensors need to be applied. However, existing wireless sensors are mainly powered by batteries. The disadvantage is that batteries have limited energy storage and need to be replaced regularly, which increases maintenance costs and reduces system reliability.

The energy harvester can convert the existing energy around the working environment of the equipment into electrical energy, replacing the battery. Existing energy harvesters mainly convert thermal energy, light energy, and vibration energy into electrical energy. The forms of converting vibration energy into electrical energy mainly include electromagnetic, piezoelectric, and electrostatic. The existing electromagnetic type mostly adopts a spring-mass system, and the vibration is amplified by the spring, so that different parts of the energy harvester generate relative motion, and the corresponding vibration energy is converted into electrical energy. When the spring-mass system is used, the selection of the elastic coefficient of the spring is easily limited by the actual spring (the spring coefficient of the actual spring has a corresponding national standard). Since the elastic coefficient is discrete, and the setting of the natural frequency of the system is related to the elastic coefficient of the spring and the quality of the mover, it is difficult to adjust the natural frequency of the system to be equal to the frequency of the vibration source. In addition, when the elastic coefficient of the actual spring is constant, there are certain requirements for the effective number of corresponding springs and the diameter of the spring wire, etc., and the installation size and space of the spring are relatively limited; currently, compression springs are mostly used in similar systems. In the case of high acceleration of the vibration source, the spring may be damaged, and at the same time, the travel of the mover is limited, and the manufacturing cost of the energy harvester is also increased.

The patent document with the publication number CN1877973 discloses a vibration power generation device for portable electronic equipment. The device uses a permanent magnet to reciprocate in the motion cavity to generate relative motion with the winding, and generates an induced current in the winding by cutting the magnetic force line, and rectifies becomes direct current, charging the battery. There is only one permanent magnet in the motion cavity of this vibration power generation device, and the induced potential generated is relatively small. At the same time, when a certain induced voltage is required, the length of the single permanent magnet is constant, so that the spring interacting with the end permanent magnet is equivalent to a spring The adjustable range of the coefficient is relatively small. Designing a vibration source and load characteristics to select the corresponding winding and spring coefficient has become a problem that needs to be solved at present.

Contents of the invention

The invention provides a permanent magnet damping linear power generation device with simple structure, high induced electromotive force and low production cost.

A permanent magnet damping linear power generation device, comprising a cylindrical casing, end covers at both ends of the casing, a mover, a stator and a fixed permanent magnet arranged in the cavity of the casing; the stator includes a The coaxial cylindrical winding bracket and the windings wound outside the winding bracket, the winding bracket is made of non-magnetic material, there is a wire lead-out slot between the winding bracket and the case, the case is provided with a wire lead-out port, and the wire leads The outlet communicates with the lead-out groove; the mover is a cylinder coaxial with the casing, located in the winding support, and the mover includes a number of axially magnetized mover permanent magnets, located in two adjacent mover The iron core between the permanent magnets of the mover and the sheath that wraps the permanent magnet of the mover and the iron core, the sheath is made of non-magnetic material, the magnetization directions of two adjacent permanent magnets of the mover are opposite, and the diameter of the permanent magnet of the mover is equal to that of the iron core; A fixed permanent magnet is fixed on the inner side of the end cover, and the magnetization direction of the fixed permanent magnet is opposite to that of the mover permanent magnet near the end of the mover of the fixed permanent magnet.

Both the casing and the end covers at both ends of the casing can be made of magnetically conductive materials. The main body of the casing can be cylindrical, cuboid or other shapes according to the actual application. The casing and the end caps are evenly distributed with connection holes for connecting The winding bracket is fixed to the case and the case is connected to the vibration source. The diameter and length of the casing can generally be determined according to actual needs. There is a wire lead-out hole at the end of the main body of the casing near the end cover, which is used to lead out the wire of the winding, so as to facilitate connection with peripheral components.

The winding support is a cylindrical body with a certain thickness. Generally, a polymer non-magnetic material can be selected. The outer wall of the winding support is provided with an annular groove. The annular groove is generally set in the middle of the outer wall of the winding support; the width and depth of the annular groove And the number of settings can be adjusted according to actual needs; the outer wall of the winding bracket is provided with a lead-out groove, the lead-out groove is connected with the annular groove, and the lead-out groove is connected with the lead-out hole of the main body of the casing, which is convenient for the winding and connection of the winding; On the one hand, the setting of the wire lead-out groove can make the connection between the winding support and the casing more compact, which is beneficial to reduce the overall volume of the power generation device. The inner side of the winding bracket is polished or sprayed with lubricant at the same time, which can reduce the friction force of the reciprocating motion of the mover and reduce the noise.

The mover is composed of a mover permanent magnet, an iron core, and a sheath covering the mover permanent magnet and the iron core. Under the mutual magnetic attraction, the mover permanent magnet and the iron core form a complete cylinder. The outer surface of the sheath is polished to further reduce the friction of the reciprocating motion of the mover; the permanent magnet of the mover can be ferrite, neodymium iron boron or samarium cobalt which are common in the market. The iron core can be composed of solid iron or laminated silicon steel sheets. The shape of the mover can also be adjusted according to actual needs. The mover permanent magnet adopts axial magnetization, which is more convenient to process and lower in production cost. The magnetization directions of the two adjacent mover permanent magnets are opposite, the magnetic lines of force in the iron core diffuse along the radial direction, and are perpendicular to the winding coils of the stator, the magnetic density in the air gap increases, and the windings of the stator vertically cut the magnetic lines of force, and the induced electromotive force increases; In practical applications, the air gap magnetic field can generally be adjusted by adjusting the relative thickness of the mover permanent magnet and the iron core, and the pole distance of the mover can be adjusted by adjusting the thickness of a pair of mover permanent magnets and the adjacent iron core. Cooperating with the stator winding coil, Adjust the waveform of the induced potential. The mover adopts multiple permanent magnets, and the number of pole pairs is large, so that the utilization rate of the stator winding coil is improved during the whole stroke of the mover. The permanent magnet of the mover and the iron core are covered with a sheath to ensure that the whole mover is integrated, which is convenient for polishing the outside of the whole mover, and reduces the friction between the mover and the stator winding support.

The inner sides of the end covers at both ends of the casing can choose to install fixed permanent magnets, and the fixed permanent magnets can also choose ferrite, NdFeB or SmCo, and the number of fixed permanent magnets can be one or two; since the end covers are made of magnetic materials , the fixed permanent magnet can be directly fixed on the inner side of the end cover through magnetic attraction, which is convenient for installation. When the charging device of the present invention is used horizontally, a fixed permanent magnet needs to be arranged on the inner side of the two end caps respectively. The fixed permanent magnet and the repulsive force of the mover permanent magnets at both ends of the mover make the mover reciprocate in the winding bracket to avoid mechanical stretching and collision. When the power generating device is used vertically, generally only a fixed permanent magnet needs to be installed inside the bottom end cover of the casing, and the mover reciprocates up and down in the winding bracket under the interaction of repulsion force and its own gravity. The interaction between the fixed permanent magnet at the end and the permanent magnet of the mover is equivalent to the spring structure, and the magnetic force equivalent spring of the fixed permanent magnet at the end and the permanent magnet of the mover is used to adjust the fixed permanent magnet at the end and the permanent magnet of the mover The thickness, area, and relative distance can continuously adjust the elastic coefficient of the equivalent spring within a certain range, so that different natural frequencies can be set for the power generation device according to different occasions. During use, the vibration frequency of the mover will eventually be equal to the vibration frequency of the vibration source. When the natural frequency of the generator itself is consistent with the vibration frequency of the vibration source, the vibration of the vibration source can be amplified to the maximum, that is, the mover The amplitude is the largest, and the relative movement between the mover and the stator is the largest, so that more electric energy can be collected and the final power generation efficiency can be improved.

The stator winding is made of enameled wire, and the winding can be a single-phase winding or a three-phase winding according to actual needs. For single-phase windings, within a period of a pair of pole distances between the movers, the directions of the magnetic fields established by the movers in the first half cycle and the second half cycle are opposite. The winding direction is reversed. Three-phase windings, within one cycle of the mover, the difference between the three-phase windings is 120 degrees in electrical angle, and the winding and connection directions of the same phase windings within different cycle ranges ensure that the back EMF of the winding is superimposed in a positive direction to obtain more back EMF. The winding directions between adjacent two sets of windings are opposite.

The beneficial effects brought by the present invention are reflected in:

(1) The power generating device of the present invention can adjust the repulsion between permanent magnets such as the thickness and area of the permanent magnet at the end of the mover and the fixed permanent magnet, that is, adjust the equivalent spring coefficient during the damping motion, combined with the force of the mover The quality can adjust the natural frequency of the system, so it is suitable for vibration sources with different frequencies within a certain range, and realizes the maximum power generation efficiency of the power generation device;

(2) By adjusting the thickness and quantity of the mover permanent magnets in the mover, combined with the thickness of the iron core and the distribution of the windings, single-phase and three-phase induced electromotive forces can be generated, and the magnitude of the induced electromotive force can be controlled to meet the needs of different occasions. need;

(3) The mechanical damping vibration conversion of the power generating device of the present invention controls the natural frequency and the control of the electric energy generated by electromagnetic action is relatively independent, can be controlled separately, and has strong practicability.

Description of drawings

Fig. 1 is a schematic structural view of the power generating device of the present invention when placed horizontally;

Fig. 2 is a sectional view of the power generating device in Fig. 1 along plane A-A;

Fig. 3 is a partial enlarged view of part B of the power generation device in Fig. 2;

Fig. 4 is a schematic structural view of the power generating device of the present invention when placed vertically;

Fig. 5 is a circuit diagram for generating a single-phase induced electromotive force by the power generating device of the present invention;

Fig. 6 is a schematic diagram of a circuit for generating three-phase induced electromotive force of the power generating device of the present invention.

Detailed ways

As shown in Figure 1, Figure 2 and Figure 4, a permanent magnet damping linear power generation device includes a casing 1, end covers at both ends of the casing 1, a stator in the casing 1, a mover, and a fixing device inside the end cover. permanent magnet9.

As shown in FIGS. 1-3 , the end cover includes a first end cover 2 and a second end cover 12 , the case 1 and the end cover are both made of magnetically conductive material, and the case 1 is cylindrical. According to different actual application occasions, the casing 1 may also be in the shape of a cuboid or other shapes. Connecting holes are evenly distributed on the casing 1 , the first end cover 2 and the second end cover 12 for fixing the winding support to the casing and connecting the casing to the vibration source. The diameter and length of the casing 1 can generally be determined according to actual needs. A wire lead-out hole 6 is left at one end of the casing 1 close to the first end cover 2 .

As shown in FIGS. 1-4 , the stator includes a winding support 3 and a winding 4 outside the winding support. The winding support 3 is a high molecular polymer non-magnetic material. The winding support 3 is a cylinder with a certain thickness. The outer wall of the winding support 3 is provided with annular grooves 10. The number of the grooves 10 is 6. The number, width and depth of the grooves 10 can be determined according to actual needs. The outer wall of the winding support 3 is provided with a wire lead-out groove 5, the wire lead-out groove 5 communicates with the groove 10 and is arranged coaxially with the winding support 3, the outlet end of the wire lead-out groove 5 communicates with the wire lead-out hole 6, and the other side far away from the wire lead-out hole 6 One end terminates in a groove close to the second end cap 12 to facilitate the arrangement of the winding 4 . The winding bracket 3 is fixedly connected by bolts through the connecting holes on the casing 1 and the end cover. The winding 4 is wound by enameled wire and is a single-phase winding. According to actual needs, the winding 4 can also be arranged as a three-phase winding to generate three-phase induced electromotive force. The inner cavity of the winding support 3 is the track for the reciprocating movement of the mover. In order to reduce resistance and noise, the inner surface can be polished and then sprayed with lubricant.

As shown in Figures 1 to 4, the mover is composed of the mover permanent magnet 7, the iron core 8, and the sheath 11 covering the mover permanent magnet 7 and the iron core 8. Under the mutual magnetic attraction, the mover permanent magnet and the iron core form a complete of cylinders. The number of mover permanent magnets 7 is 7, and ferrite, neodymium iron boron or samarium cobalt common in the market can be selected, and the number of mover permanent magnets can also be adjusted according to actual needs. The number of iron cores 8 is 6, which can be made of solid iron or stacked with silicon steel sheets. The shape of the mover can also be adjusted according to actual needs. The magnetization directions of the two adjacent mover permanent magnets are opposite, and the magnetic lines of force in the core diffuse radially, perpendicular to the winding coils of the stator, which increases the magnetic density in the air gap, and the windings of the stator vertically cut the lines of force, and the induced potential increases ; In practical applications, the pole distance of the mover can be adjusted by adjusting the relative thickness of the mover permanent magnet and the mover core, adjusting the air gap magnetic field, adjusting the thickness of the mover permanent magnet and the adjacent iron core, and cooperating with the stator winding coil. Adjust the waveform of the back EMF. The mover permanent magnet 7 and the iron core 8 are covered with a sheath 11 to ensure that the whole mover is integrated, to facilitate the polishing process on the outside of the whole mover, and to reduce the friction between the mover and the stator winding support 3 .

As shown in Figure 1, when the power generating device of the present invention is used horizontally, a fixed permanent magnet 9 is respectively provided on the inside of the first end cover 2 and the second end cover 12, and the fixed permanent magnet 9 is axially magnetized, and the left side The magnetization direction of the fixed permanent magnet 9 is opposite to that of the mover permanent magnet 7 at the left end of the mover, and the magnetization direction of the fixed permanent magnet 9 on the right side is opposite to that of the mover permanent magnet 7 at the right end of the mover. A repulsive force is generated between the permanent magnets 9. When there is no external force, the mover is in a stable and balanced state. The mover keeps the same distance from the fixed permanent magnets 9 at both ends. When it is subjected to external vibration, the mover loses balance and moves to one end. The distance between the sub permanent magnet 7 and this end decreases, and the repulsive force increases, hindering the mover from moving further to this end, and the mover constantly reciprocates by inertia and the repulsive effect of the fixed permanent magnets 9 at both ends. As shown in Figure 4, when the power generating device of the present invention is vertically installed and used, it only needs to be provided with a fixed permanent magnet 9 on the inside of the first end cover 2, and the movement can be realized under the action of the repulsive force and the weight of the mover itself. The up and down reciprocating motion of the sub.

As shown in Figure 5, when the present invention needs to generate a single-phase induced electromotive force, the winding 4 is set as a single-phase winding, and the winding 4 forms an AC power supply S, and the alternating current generated by the power supply S passes through the single-phase diodes D1, D2, D3 and D4 Carry out single-phase rectification, charge the capacitor C of the energy storage device after rectification, and the capacitor C provides electric energy to the load appliance L. As shown in Figure 6, when the present invention needs to generate a three-phase induced current electromotive force, the winding 4 needs to be set as a three-phase winding. D3, D4, D5 and D6 perform three-phase rectification, and then charge the capacitor C of the energy storage device, and the capacitor C provides electric energy to the load device L. The capacitor C in Fig. 5 and Fig. 6 can also be replaced by a storage battery according to actual needs.

Claims (7)

1. a permanent magnet damping linear generating set comprises the end cap at columnar casing (1), casing (1) two ends and is arranged on mover and the stator in casing (1) cavity; Described stator comprises and coaxial columnar winding support (3) of casing (1) and the winding (4) that is wrapped in winding support (3) outside; Winding support (3) is a non-magnet material; Leave lead lead-out groove (5) between winding support (3) and the casing (1); Casing (1) is provided with lead outlet (6), and lead outlet (6) is communicated with lead lead-out groove (5); Described mover is and the coaxial cylinder of casing (1); Be positioned at winding support (3); It is characterized in that described mover comprises the rotor permanent magnet (7), the iron core (8) between adjacent two rotor permanent magnet of some axial chargings and with the sheath (11) of rotor permanent magnet (7) and (8) unshakable in one's determination parcel, sheath (11) is a non-magnet material; Adjacent two rotor permanent magnet magnetizing directions are opposite, rotor permanent magnet (7) and (8) equal diameters unshakable in one's determination; The inboard of described end cap is fixed with fixed permanent magnet (9), and fixed permanent magnet (9) is opposite with rotor permanent magnet magnetizing direction near the mover end of fixed permanent magnet (9); Described winding support (3) outer wall is provided with the annular groove (10) that is used to place winding (4); Described winding support (3) outer wall is provided with lead lead-out groove (5), and lead lead-out groove (5) is connected with annular groove (10); The end cap at described casing (1) and casing (1) two ends is made up of permeability magnetic material.

2. permanent magnet damping linear generating set according to claim 1 is characterized in that, described sheath (11) and winding support (3) are the high molecular polymer non-magnet material.

3. permanent magnet damping linear generating set according to claim 1 is characterized in that, described rotor permanent magnet (7) and fixed permanent magnet (9) are ferrite, neodymium iron boron or SmCo.

4. permanent magnet damping linear generating set according to claim 1 is characterized in that, described iron core (8) is made up of solid-iron or is made up of silicon steel plate packing.

5. permanent magnet damping linear generating set according to claim 1 is characterized in that, described winding (4) is single-phase winding or three phase windings.

6. permanent magnet damping linear generating set according to claim 1 is characterized in that, described casing (1) vertically is provided with, and the end cap inboard of casing (1) bottom is provided with fixed permanent magnet (9).

7. permanent magnet damping linear generating set according to claim 1 is characterized in that, described casing (1) horizontal positioned, and end cap inboard, casing (1) two ends is respectively equipped with fixed permanent magnet (9).

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