Hybrid nano generator and power management circuit thereof

Abstract

The invention belongs to the technical field of generators, and particularly relates to a hybrid nano generator and a power management circuit thereof, comprising a shell, and an electromagnetic power generation unit, a friction power generation unit and a piezoelectric power generation unit which are located in the shell; and a corresponding power management circuit. The interior of the shell is connected with the top end and the bottom end in a penetrating mode through a glass fiber connecting shaft. A friction power generation unit, an electromagnetic power generation unit and a piezoelectric power generation unit are sequentially mounted at the bottom end, opposite to the shell, of the glass fiber connecting shaft; the piezoelectric power generation unit comprises at least four cantilevers and a disc, one end of each cantilever is fixed on the disc, and a mass block is placed on the upper surface of the other end; the center of the disc is connected with a glass fiber connecting shaft, and the inner sides of the upper surfaces of the four cantilevers are covered with PZT materials. According to the hybrid nano generator, vibration energy in the environment can be converted into electric energy, and energy is supplied to wireless sensor network nodes.

Description

Technical Field

[0001] The present invention belongs to the technical field of generators, and in particular relates to a hybrid nanogenerator and a power management circuit thereof. Background Art

[0002] With the popularization of the fifth generation of mobile communication technology (5G) and the continuous breakthroughs in electronic information technology, the Internet of Things has developed rapidly. In the Internet of Things architecture, wireless sensor network nodes that integrate power supply, diversified sensing and communication functions are key components. These nodes are widely distributed in various fields, such as industrial monitoring, smart homes, environmental testing, etc., and play an important role in realizing the Internet of Everything.

[0003] At present, traditional lithium batteries and nickel-zinc batteries are widely used power sources for powering portable devices such as wireless sensor network nodes. However, these traditional batteries have many significant disadvantages. On the one hand, they need to be charged frequently, which not only brings inconvenience to users, but also in some special environments or application scenarios (such as monitoring equipment in remote areas), frequent charging may cause interruptions in device operation. On the other hand, these batteries have poor flexibility and are difficult to adapt to some devices with special requirements for shape, size and installation method. In addition, traditional batteries will cause environmental pollution during production, use and disposal, which is not conducive to sustainable development. These shortcomings seriously limit the application of traditional batteries in the further development of fields such as the Internet of Things, so the development of reliable portable power sources has become an urgent problem to be solved.

[0004] In the process of exploring new power technology, nanogenerators have received extensive attention. In recent years, people have been increasingly studying nanogenerators, and their types include electromagnetic, piezoelectric, electrostatic and friction nanogenerators. However, nanogenerators based on a single power generation mechanism have serious shortcomings. For example, they often have the problem of low conversion efficiency, which means that when converting other forms of energy such as mechanical energy and vibration energy into electrical energy, a large amount of energy is wasted and cannot effectively power the device. At the same time, the frequency band of nanogenerators with a single mechanism is narrow and can only work effectively within a specific frequency range, which limits their application under different working conditions. In addition, the device life of this type of generator is low, and it is prone to failure or performance degradation, which further affects its practical application value. These problems make nanogenerators with a single power generation mechanism face huge obstacles in large-scale promotion and application.

[0005] In order to overcome the limitations of single-generator nanogenerators, people began to study dual-hybrid and triple-hybrid generator mechanisms. Therefore, a nanogenerator that can convert vibration energy in the environment into electrical energy and power wireless sensor network nodes is needed. Summary of the invention

[0006] The technical problem solved by the present invention is to provide a hybrid nanogenerator and a power management circuit thereof, so as to realize the conversion of vibration energy in the environment into electrical energy and provide energy for wireless sensor network nodes.

[0007] The basic solution provided by the present invention is: a hybrid nanogenerator, comprising a shell and an electromagnetic power generation unit, a friction power generation unit, and a piezoelectric power generation unit located in the shell;

[0008] The top and bottom ends of the shell are connected by a glass fiber connecting shaft; the friction power generation unit, the electromagnetic power generation unit and the piezoelectric power generation unit are sequentially installed on the glass fiber connecting shaft relative to the bottom end of the shell;

[0009] The piezoelectric power generation unit includes at least four cantilevers and a disc, one end of the cantilever is fixed on the disc, and a mass block is placed on the upper surface of the other end; the center of the disc is connected to the glass fiber coupling, and the inner sides of the upper surfaces of the four cantilevers are covered with PZT material.

[0010] The principle and advantage of the present invention are as follows: the hybrid nanogenerator designed in the present invention combines three power generation modes: electromagnetic power generation, friction power generation and piezoelectric power generation. Among them, the output of the nanogenerator based on friction power generation has the characteristics of high voltage and low current, the output of the electromagnetic nanogenerator has the characteristics of low voltage and high current, and the piezoelectric nanogenerator has the characteristics of small size and high energy density. Therefore, the present application mixes electromagnetic power generation, friction power generation and piezoelectric power generation, so that the hybrid nanogenerator couples the three power generation modes, which can achieve complementary advantages, improve energy conversion efficiency, and enrich the power output characteristics;

[0011] On the basis of the coupled power generation mode of the above-mentioned hybrid nanogenerator, the piezoelectric power generation unit of this scheme is designed to include at least 4 cantilevers. The 4 cantilevers are in the shape of a windmill and are evenly distributed around the center of the glass fiber coupling. Therefore, each cantilever can be regarded as a piezoelectric nanogenerator module. This scheme integrates at least 4 piezoelectric nanogenerator modules to increase the overall output; furthermore, this scheme overturns the PZT material, i.e., lead zirconate titanate, on the inner side of the upper surface of the cantilever, and places a mass block at the end of the upper surface. The presence of the cantilever and the mass block produces a vibration damping effect during operation, which can increase the mass and dissipation capacity of the vibration system of the hybrid nanogenerator of this scheme, thereby reducing the amplitude and vibration duration of the vibration system, and converting the vibration energy in the environment into electrical energy. Therefore, the vibration damping effect produced by the piezoelectric power generation unit structure designed in this scheme helps to reduce the resonance phenomenon of the vibration system and improve the stability and performance of the system, especially when applied to wireless sensing systems, it greatly improves the stability of the nanogenerator and provides high performance.

[0012] Furthermore, an upper end cover and a lower end cover are respectively fixed at the upper and lower ends of the shell, and a glass fiber coupling is installed at the center of the upper end cover and the lower end cover through a buckle, and the glass fiber coupling passes through the upper end cover and the lower end cover.

[0013] Beneficial effect: The internal power generation unit is covered by the shell, the upper end cover and the lower end cover, which can not only play a protective role but also reduce noise.

[0014] Furthermore, the electromagnetic power generation unit includes an induction coil, a fixed magnet and a suspension magnet. The fixed magnet is fixed to the inner surface of the lower end cover with the glass fiber coupling as the center. The induction coil is placed around the fixed magnet. The suspension magnet is fixed to the bottom of the piezoelectric power generation unit. A friction power generation unit is arranged between the fixed magnet and the suspension magnet.

[0015] Beneficial effects: The fixed magnet and the suspended magnet constitute a magnetic levitation structure. On the one hand, it has higher sensitivity and lower energy loss than the traditional spring or cantilever beam design, which is conducive to collecting tiny energy. On the other hand, the suspension structure design can avoid mechanical fatigue or damage and extend the life of the device.

[0016] Furthermore, the fixed magnet has an N pole at the top and an S pole at the bottom; the suspended magnet has an S pole at the top and an N pole at the bottom.

[0017] Beneficial effect: The fixed magnet and the suspended magnet repel each other, so that the magnetic flux lines generated enter from the S pole and exit from the N pole.

[0018] Furthermore, the friction power generation unit includes a first gasket, a first copper foil layer, a polytetrafluoroethylene film, a second copper foil layer, and a second gasket. The first gasket is glued and fixed to the upper surface of the fixed magnet, the first copper foil layer is glued to the upper surface of the first gasket, the polytetrafluoroethylene film is glued to the upper surface of the first copper foil layer, the second copper foil layer is glued to the lower surface of the second gasket, and the second gasket is glued to the lower surface of the suspended magnet. A gap is provided between the second copper foil layer and the polytetrafluoroethylene film.

[0019] Beneficial effect: An electrode is formed by pasting the first gasket and the first copper foil layer, and the first copper foil layer is pasted and fixed to the polytetrafluoroethylene film to serve as a lower friction layer; the second gasket and the second copper foil layer are pasted to serve as both an upper friction layer and an electrode, so that when the upper friction layer and the lower friction layer generate up and down movements through a vibration system, friction power generation is generated based on the different electronegativity between the materials of the upper friction layer and the lower friction layer.

[0020] A power management circuit for a hybrid nanogenerator is applied to the above-mentioned hybrid nanogenerator, including at least four piezoelectric power generation unit management circuits, an electromagnetic power generation unit management circuit and a friction power generation unit management circuit. The piezoelectric power generation unit management circuits share an inductor, and the inductor is used to resonate with the inherent capacitance inside the piezoelectric power generation unit when the voltage reaches the positive and negative cycle peaks to extract capacitor energy; each piezoelectric power generation unit management circuit is also connected to the electromagnetic power generation unit management circuit and the friction power generation unit management circuit through an energy storage capacitor.

[0021] Furthermore, the piezoelectric power generation unit management circuit includes 2 NPN transistors, 2 PNP transistors, 1 small capacitor, and 2 diodes. The at least 4 piezoelectric power generation unit management circuits adopt a P-SSHI topology structure; wherein the 4 transistors are symmetrically connected, and a NPN transistor and a PNP transistor on the right side of the symmetry axis are combined to form a control switch for the negative half cycle, and a NPN transistor and a PNP transistor on the left side of the symmetry axis are combined to form a control switch for the positive half cycle. The small capacitor is used to maintain a voltage reference during peak detection, and the 2 diodes are respectively responsible for the rectification function of the positive half cycle and the negative half cycle of the AC signal generated by the piezoelectric unit.

[0022] Beneficial effects: In the piezoelectric power generation unit management circuit, four transistors are used to form the control switches of the negative half-cycle and the positive half-cycle in the management circuit. A small capacitor is used to provide the management circuit with a voltage reference maintenance function during peak detection. Two diodes are used to rectify the positive and negative half-cycles of the AC signal, which reduces the number of diodes used in conventional circuits and facilitates the effective collection and conversion of bidirectional energy.

[0023] Furthermore, the electromagnetic power generation unit management circuit includes two diodes, the two diodes are respectively responsible for the rectification function of the positive half cycle and the negative half cycle of the AC signal in the electromagnetic power generation unit, and the two diodes are also connected to the energy storage capacitor;

[0024] The friction power generation unit management circuit includes two diodes, which are respectively responsible for the rectification functions of the positive half cycle and the negative half cycle of the AC signal in the friction power generation unit, and the two diodes are also connected to the energy storage capacitor.

[0025] Principles and advantages of the present invention: In this solution, the piezoelectric power generation unit management circuit is based on the P-SSHI topology structure and adopts a common inductor method to transfer the energy in the inherent capacitance of the piezoelectric power generation unit to the inductance of the resonant network, while quickly flipping the voltage across the piezoelectric unit, ultimately achieving high energy extraction efficiency of the circuit; at the same time, the electromagnetic power generation unit management circuit and the friction power generation unit management circuit use two diodes to connect to the energy storage capacitor to achieve voltage doubling rectification and simultaneously merge into the energy storage capacitor, thereby enhancing the simplicity and scalability of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 An exploded schematic diagram of a hybrid nanogenerator according to an embodiment of the present invention;

[0027] Figure 2 A schematic diagram of the structural layout of a hybrid nanogenerator in an embodiment of the present invention;

[0028] Figure 3 This is a schematic diagram of the hybrid nanogenerator in the second stage according to an embodiment of the present invention;

[0029] Figure 4 It is a schematic diagram of the hybrid nanogenerator in the third stage according to an embodiment of the present invention;

[0030] Figure 5 It is a schematic diagram of the hybrid nanogenerator in the fourth stage according to an embodiment of the present invention;

[0031] Figure 6 It is a schematic diagram of the hybrid nanogenerator in the fifth stage according to an embodiment of the present invention;

[0032] Figure 7 Schematic diagram of a power management circuit of a hybrid nanogenerator in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following is further described in detail through specific implementation methods:

[0034] The symbols in the drawings of the specification include: upper end cover 1, shell 2, cantilever 3, suspension magnet 4, second stainless steel gasket 5, first stainless steel gasket 6, glass fiber coupling 7, induction coil 8, fixed magnet 9, lower end cover 10.

[0035] The embodiment is basically as shown in the attached Figure 1As shown: A hybrid nanogenerator includes a shell 2 and an electromagnetic power generation unit, a friction power generation unit, and a piezoelectric power generation unit located in the shell 2, wherein the shell 2 is made of acrylic material, and the shell 2 is cylindrical in the present application, and an upper end cover 1 and a lower end cover 10 are respectively provided at both ends of the shell 2, and circular holes are opened in the centers of the upper end cover 1 and the lower end cover 10, and a glass fiber coupling 7 passes through the circular holes, and the glass fiber coupling 7 is fixed at the central circular holes of the upper end cover 1 and the lower end cover 10 by means of snaps.

[0036] The electromagnetic power generation unit includes an induction coil 8, a fixed magnet 9 and a suspension magnet 4; the friction power generation unit includes a first gasket, a first copper foil layer, a polytetrafluoroethylene film, a second copper foil layer, and a second gasket, wherein the first gasket and the second gasket are made of stainless steel, that is, the first gasket and the second gasket are also called a first stainless steel gasket 6 and a second stainless steel gasket 5; the piezoelectric power generation unit includes at least four cantilevers 3 and a disc, one end of the cantilever 3 is fixed on the disc, and a mass block is placed on the upper surface of the other end; the center of the disc is connected to a glass fiber coupling 7, and the inner side of the upper surface of the four cantilevers 3 is covered with PZT material;

[0037] like Figure 1 As shown, with the glass fiber coupling 7 as the center, a fixed magnet 9 is installed on the inner surface of the lower end cover 10. In this solution, the fixed magnet 9 is annular, and the induction coil 8 is placed around the outer periphery of the annular fixed magnet 9; then, as shown in FIG. Figure 2 As shown, the first stainless steel gasket 6, the first copper foil layer, and the polytetrafluoroethylene film are arranged in sequence from bottom to top with the induction coil 8, the lower surface of the first stainless steel gasket 6 is glued and fixed to the upper surface of the induction coil 8, the upper surface of the first stainless steel gasket 6 is glued to the lower surface of the first copper foil layer, and the upper surface of the first copper foil layer is glued to the lower surface of the polytetrafluoroethylene film, so that the first stainless steel gasket 6 and the first copper foil layer form an electrode, and the first stainless steel gasket 6, the first copper foil layer and the polytetrafluoroethylene film form a lower friction layer;

[0038] Furthermore, a second copper foil layer is arranged above the polytetrafluoroethylene film, and there is a gap between the polytetrafluoroethylene film and the second copper foil layer. The upper surface of the second copper foil layer is adhered to the lower surface of the second stainless steel gasket 5, and the upper surface of the second stainless steel gasket 5 is adhered to the suspension magnet 4. The suspension magnet 4 is then adhered and fixed to the disk of the piezoelectric power generation unit. Specifically, a through hole is opened in the center of the disk, and the disk is connected to the glass fiber coupling 7 through the through hole. The suspension magnet 4 is adhered and fixed to the lower surface of the disk. In this way, the electromagnetic power generation unit, the friction power generation unit and the piezoelectric power generation unit are fixed inside the shell 2 through the above-mentioned connection method.

[0039] As for the working principles of the above-mentioned electromagnetic power generation unit, friction power generation unit and piezoelectric power generation unit, firstly, in the electromagnetic power generation unit:

[0040] Electromagnetic power generation is based on Faraday's law of electromagnetic induction, that is, a conductor placed in a changing magnetic flux will generate an electromotive force. If the conductor is closed into a loop, the electromotive force will drive the electrons to flow and form an induced current. Therefore, the electromagnetic power generation unit in this scheme is based on the above principle, and the induction coil 8 is a closed circuit. The fixed magnet 9 has the N pole on the top and the S pole on the bottom, and the suspended magnet 4 has the S pole on the top and the N pole on the bottom. The generated magnetic flux lines enter from the S pole and exit from the N pole. When the suspended magnet 4 moves in the direction close to the induction coil 8, the magnetic field strength increases. According to Lenz's law and the right-hand rule, an induced current from left to right is generated in the induction coil 8 at this time (the left and right directions are based on looking down at the induction coil 8), and when the suspended magnet 4 moves in the direction away from the induction coil 8, an induced current from right to left is generated.

[0041] The working principle of the friction power generation unit is as follows: the friction power generation unit is based on electrostatic induction and friction electrification effect. Therefore, in this solution, the lower surface of the first stainless steel gasket 6 is glued and fixed to the upper surface of the fixed magnet 9, and the first copper foil layer is glued to the upper surface of the first stainless steel gasket 6 as an electrode; a polytetrafluoroethylene film is glued to the upper surface of the first copper foil layer as a lower friction layer; the second copper foil layer is glued to the lower surface of the second stainless steel gasket 5 as both an upper friction layer and an electrode; Figure 3 As shown, when the magnetic suspension structure in the housing 2 vibrates to a certain frequency, the suspension magnet 4 drives the second stainless steel gasket 5 and the second copper foil layer to move up and down. When the second copper foil layer contacts the polytetrafluoroethylene film, since the polytetrafluoroethylene film has a higher electronegativity than copper, electrons are transferred from the material with a lower electronegativity to the material with a higher electronegativity. Therefore, the surface of the second copper foil layer is positively charged, and the surface of the polytetrafluoroethylene film is negatively charged. Figure 4 As shown, when the suspension magnet 4 starts to move upward, the second copper foil layer is separated from the polytetrafluoroethylene film, a small air gap is formed between the two, and a potential difference is formed between the two electrodes. If the two electrodes are connected through an external circuit, a reverse potential difference will be generated to balance the electrostatic field, that is, electrons flow from the first copper foil layer to the second copper foil layer; Figure 5 As shown, when the second copper foil layer moves to the original position, the voltage reaches the maximum saturation value. If the component is stimulated again at this time, the second copper foil layer approaches the polytetrafluoroethylene film again, and the distance between the two decreases, making the potential of the first copper foil layer higher than that of the second copper foil layer, and electrons flow from the second copper foil layer back to the first copper foil layer.

[0042] Working principle of piezoelectric power generation unit: The piezoelectric power generation unit is based on the piezoelectric effect. In this scheme, the four cantilevers 3 in the piezoelectric power generation unit form a windmill shape with the disk. PZT material is attached to the inner side of the upper surface of each cantilever 3 to form a PZT thick film, and a mass block is adhered to the end of the upper surface. Under the vibration condition of the magnetic levitation structure, according to the piezoelectric effect, the lattice structure of the PZT material will be distorted, resulting in the separation of positive and negative charges, thereby generating charges on the surface of the PZT material. The mismatch in the distribution of this charge will generate an electric field, and finally form a voltage at both ends of the PZT material; and the presence of the mass block can increase the mass and dissipation capacity of the vibration system, thereby reducing the amplitude and vibration duration of the vibration system. This vibration damping effect helps to reduce the resonance phenomenon of the vibration system and improve the stability and performance of the system.

[0043] Therefore, based on the working principles of the above electromagnetic power generation unit, friction power generation unit, and piezoelectric power generation unit, the overall power generation process is:

[0044] Phase 1: Figure 2 As shown, the hybrid nanogenerator is not stimulated, the suspension magnet 4 does not move, no induced current is generated in the induction coil 8, the PZT thick film does not deform, the upper and lower friction layers do not contact, and no charge transfer occurs;

[0045] The second stage: Figure 3 As shown, the hybrid nanogenerator is stimulated, the suspension magnet 4 moves downward, the magnetic flux passing through the induction coil 8 increases, an induced current is generated in the induction coil 8, and the PZT thick film is deformed. Different types of charges are generated on the upper and lower surfaces (positive on the upper surface and negative on the lower surface). The upper friction layer and the lower friction layer are in contact with each other, the surface of the second copper foil is positively charged, and the surface of the polytetrafluoroethylene film is negatively charged.

[0046] The third stage: Figure 4 As shown, the suspension magnet 4 moves upward, the magnetic flux passing through the induction coil 8 decreases, an induced current is generated in the induction coil 8, and the PZT thick film recovers its deformation. Different types of charges are generated on the upper and lower surfaces (negative on the upper surface and positive on the lower surface). The upper friction layer and the lower friction layer are separated from each other, and a small air gap is formed between the two. A potential difference is formed between the two electrodes, and electrons flow from the first copper foil layer to the second copper foil layer.

[0047] Stage 4: Figure 5 As shown, the suspension magnet 4 moves upward to the initial position, the electromagnetic power generation unit is consistent with the piezoelectric power generation unit and the third stage, and the voltage of the friction power generation unit reaches the maximum saturation value;

[0048] Stage 5: Figure 6As shown, the hybrid nanogenerator is stimulated again, the suspension magnet 4 moves downward, the magnetic flux passing through the induction coil 8 increases, and an induced current is generated in the coil again, which flows in from the left and out from the right. The PZT thick film is deformed, and different types of charges are generated on the upper and lower surfaces (positive on the top and negative on the bottom). The distance between the upper and lower friction layers is reduced, making the potential of the first copper foil layer higher than that of the second copper foil layer, and electrons flow back from the second copper foil layer to the first copper foil layer. The subsequent power generation process is repeated in sequence.

[0049] In another embodiment of the present embodiment, a power management circuit of a hybrid nanogenerator is also included, which is applied to the above-mentioned hybrid nanogenerator, specifically, including at least 4 piezoelectric power generation unit management circuits, an electromagnetic power generation unit management circuit and a friction power generation unit management circuit, wherein the piezoelectric power generation unit management circuits share an inductor (L1), and the inductor (L1) is used to resonate with the inherent capacitance inside the piezoelectric power generation unit when the voltage reaches the positive and negative cycle peak values ​​to extract capacitor energy; each piezoelectric power generation unit management circuit is also connected to the electromagnetic power generation unit management circuit and the friction power generation unit management circuit through an energy storage capacitor.

[0050] Specifically, Figure 7 As shown, the piezoelectric power generation unit management circuit includes two NPN transistors (Q2 and Q4), two PNP transistors (Q1, Q3), a small capacitor (C1), and two diodes (D1, D2). The at least four piezoelectric power generation unit management circuits adopt a P-SSHI topology structure; wherein the four transistors are symmetrically connected, and a combination of an NPN transistor and a PNP transistor on the right side of the symmetry axis constitutes a control switch for the negative half cycle, and a combination of an NPN transistor and a PNP transistor on the left side of the symmetry axis constitutes a control switch for the positive half cycle. The small capacitor is used to maintain the voltage reference during peak detection, and the two diodes are respectively responsible for the rectification function of the positive half cycle and the negative half cycle of the AC signal generated by the piezoelectric unit. In this scheme, the energy storage capacitors are set to 2, namely C store1 and C store2 .

[0051] The electromagnetic power generation unit management circuit includes two diodes (D5, D6), which are responsible for the rectification function of the positive half cycle and the negative half cycle of the AC signal in the electromagnetic power generation unit respectively, and the two diodes are also connected to the energy storage capacitor C store1 and C store2 ;

[0052] The friction power generation unit management circuit includes two diodes (D7, D8), which are responsible for the rectification function of the positive half cycle and the negative half cycle of the AC signal in the friction power generation unit respectively, and the two diodes are also connected to the energy storage capacitor C store1 and C store2 .

[0053] Therefore, based on the above structural description, the working principle of the power management circuit of the hybrid nanogenerator in this scheme is:

[0054] Piezoelectric power generation unit (with Figure 7 Take PEG1 as an example): In the initial stage, PEG1 is in the positive half cycle, and first charges the small capacitor C1 through the base and emitter of the NPN transistor Q4. When the voltage of PEG1 reaches the conduction voltage of the diode D1, it starts to charge the energy storage capacitor C store1 Charging; when the vibration displacement of PEG1 reaches the peak value, the emitter junction of PNP transistor Q1 is turned on, and its collector is immediately connected to the base of NPN transistor Q2, and current flows in. NPN transistor Q2 is turned on, and at this time, the inductor L1 and the inherent capacitance inside the piezoelectric generating unit are triggered to produce LC resonance, and the energy of the inherent capacitance will be extracted into the inductor L1. Similarly, in the negative half cycle, the LC resonance is triggered by the conduction of PNP transistor Q3.

[0055] Working principle of electromagnetic generating unit: In the positive half cycle, when the diode D5 conduction threshold is reached, EMG starts to store energy for capacitor C store1 Charging; in the negative half cycle, when the conduction threshold of diode D6 is reached, EMG and C store1 At the same time, C store2 Charging, this process is called voltage doubling rectification.

[0056] The working principle of the friction power generation unit is the same as that of the electromagnetic power generation unit.

[0057] Therefore, in this scheme, the piezoelectric power generation unit management circuit is based on the P-SSHI topology structure and adopts a common inductor method to transfer the energy in the inherent capacitance of the piezoelectric power generation unit to the inductance of the resonant network, while quickly flipping the voltage across the piezoelectric unit, ultimately achieving high energy extraction efficiency of the circuit; at the same time, the electromagnetic power generation unit management circuit and the friction power generation unit management circuit use two diodes to connect to the energy storage capacitor to achieve voltage doubling rectification and simultaneously merge into the energy storage capacitor, thereby enhancing the simplicity and scalability of the circuit.

[0058] The above are only embodiments of the present invention. Common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. Ordinary technicians in the relevant field know all the common technical knowledge in the technical field to which the invention belongs before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. A hybrid nanogenerator, characterized in that: It includes a shell and an electromagnetic power generation unit, a friction power generation unit, and a piezoelectric power generation unit located in the shell; The top and bottom ends of the shell are connected by a glass fiber connecting shaft; the friction power generation unit, the electromagnetic power generation unit and the piezoelectric power generation unit are sequentially installed on the glass fiber connecting shaft relative to the bottom end of the shell; The piezoelectric power generation unit includes at least four cantilevers and a disc, one end of the cantilever is fixed on the disc, and a mass block is placed on the upper surface of the other end; the center of the disc is connected to the glass fiber coupling, and the inner sides of the upper surfaces of the four cantilevers are covered with PZT material.

2. A hybrid nanogenerator according to claim 1, characterized in that: The upper and lower ends of the shell are respectively fixed with an upper end cover and a lower end cover, and a glass fiber coupling is installed at the center of the upper end cover and the lower end cover through a buckle, and the glass fiber coupling passes through the upper end cover and the lower end cover.

3. A hybrid nanogenerator according to claim 2, characterized in that: The electromagnetic power generation unit includes an induction coil, a fixed magnet and a suspension magnet. The fixed magnet is fixed to the inner surface of the lower end cover with the glass fiber coupling as the center. The induction coil is placed around the fixed magnet. The suspension magnet is fixed to the bottom of the piezoelectric power generation unit. A friction power generation unit is arranged between the fixed magnet and the suspension magnet.

4. A hybrid nanogenerator according to claim 3, characterized in that: The fixed magnet has an N pole at the top and an S pole at the bottom; the suspended magnet has an S pole at the top and an N pole at the bottom.

5. A hybrid nanogenerator according to claim 4, characterized in that: The friction power generation unit includes a first gasket, a first copper foil layer, a polytetrafluoroethylene film, a second copper foil layer, and a second gasket. The first gasket is glued and fixed to the upper surface of the fixed magnet, the first copper foil layer is glued to the upper surface of the first gasket, the polytetrafluoroethylene film is glued to the upper surface of the first copper foil layer, the second copper foil layer is glued to the lower surface of the second gasket, and the second gasket is glued to the lower surface of the suspended magnet. A gap is provided between the second copper foil layer and the polytetrafluoroethylene film.

6. A power management circuit for a hybrid nanogenerator, applied to a hybrid nanogenerator as claimed in any one of claims 1 to 5, characterized in that: It includes at least 4 piezoelectric power generation unit management circuits, an electromagnetic power generation unit management circuit and a friction power generation unit management circuit. The piezoelectric power generation unit management circuits share an inductor, which is used to resonate with the inherent capacitance inside the piezoelectric power generation unit when the voltage reaches the positive and negative cycle peaks to extract capacitor energy; each piezoelectric power generation unit management circuit is also connected to the electromagnetic power generation unit management circuit and the friction power generation unit management circuit through an energy storage capacitor.

7. The power management circuit of a hybrid nanogenerator according to claim 6, characterized in that: The piezoelectric power generation unit management circuit includes 2 NPN transistors, 2 PNP transistors, 1 small capacitor, and 2 diodes. The at least 4 piezoelectric power generation unit management circuits adopt a P-SSHI topology structure; wherein the 4 transistors are symmetrically connected, and a combination of an NPN transistor and a PNP transistor on the right side of the symmetry axis constitutes a control switch for the negative half cycle, and a combination of an NPN transistor and a PNP transistor on the left side of the symmetry axis constitutes a control switch for the positive half cycle. The small capacitor is used to maintain a voltage reference during peak detection, and the 2 diodes are respectively responsible for the rectification function of the positive half cycle and the negative half cycle of the AC signal generated by the piezoelectric unit.

8. The power management circuit of a hybrid nanogenerator according to claim 7, characterized in that: The electromagnetic power generation unit management circuit includes two diodes, which are responsible for the rectification functions of the positive half cycle and the negative half cycle of the AC signal in the electromagnetic power generation unit respectively, and the two diodes are also connected to the energy storage capacitor; The friction power generation unit management circuit includes two diodes, which are respectively responsible for the rectification functions of the positive half cycle and the negative half cycle of the AC signal in the friction power generation unit, and the two diodes are also connected to the energy storage capacitor.

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