A hybrid nanogenerator and its power management circuit

Abstract

The present invention belongs to the field of generator technology, and particularly relates to a hybrid nanogenerator and its power management circuit. The nanogenerator comprises a housing and an electromagnetic generator unit, a triboelectric generator unit, and a piezoelectric generator unit located within the housing; and a corresponding power management circuit. A glass fiber coupling extends through the housing, connecting the top and bottom ends. The triboelectric generator unit, the electromagnetic generator unit, and the piezoelectric generator unit are sequentially mounted on the fiberglass coupling relative to the bottom end of the housing. The piezoelectric generator unit comprises at least four cantilevers and a disk, one end of the cantilever being fixed to the disk, and a mass placed on the top surface of the other end. The center of the disk is connected to the fiberglass coupling, and the inner surfaces of the top surfaces of the four cantilevers are coated with PZT material. The hybrid nanogenerator of the present invention can convert vibration energy in the environment into electrical energy and power 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 widespread adoption of fifth-generation mobile communication technology (5G) and continuous breakthroughs in electronic information technology, the Internet of Things (IoT) has experienced rapid growth. Wireless sensor network nodes, integrating power supply, diverse sensing, and communication functions, are key components of the IoT architecture. These nodes are widely deployed in various fields, such as industrial monitoring, smart homes, and environmental monitoring, playing a vital role in enabling the interconnection of everything.

[0003] Currently, 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 require frequent charging, 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 device operation interruptions. 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 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. Therefore, the development of reliable portable power sources has become an urgent problem to be solved.

[0004] In the exploration of new power technologies, nanogenerators have garnered widespread attention. In recent years, research on nanogenerators has intensified, encompassing electromagnetic, piezoelectric, electrostatic, and triboelectric nanogenerators. However, nanogenerators based on a single generator mechanism suffer from significant shortcomings. For example, they often suffer from low conversion efficiency, meaning that when converting other forms of energy, such as mechanical and vibrational energy, into electrical energy, a significant amount of energy is wasted, rendering them ineffective in powering devices. Furthermore, single-mechanism nanogenerators have a narrow frequency bandwidth, operating effectively only within a specific frequency range, limiting their applicability under various operating conditions. Furthermore, these generators suffer from a short device lifespan and are prone to failure or performance degradation, further impacting their practical application. These issues present significant obstacles to the widespread adoption of single-mechanism nanogenerators.

[0005] To overcome the limitations of single-generator nanogenerators, researchers have begun 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 inside the shell;

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

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

[0010] The principles and advantages of the present invention are as follows: the hybrid nanogenerator designed in the present invention combines three power generation modes: electromagnetic power generation, triboelectric power generation, and piezoelectric power generation. Among them, the nanogenerator based on triboelectric power generation has the characteristics of high voltage and low current output, the electromagnetic nanogenerator has the characteristics of low voltage and high current output, and the piezoelectric nanogenerator has the characteristics of small size and high energy density. Therefore, the present application combines electromagnetic power generation, triboelectric 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] Based on the coupled power generation mode of the above-mentioned hybrid nanogenerator, this solution designs the piezoelectric power generation unit to include at least four cantilevers. These four cantilevers are windmill-shaped and evenly distributed around the center of the glass fiber coupling. Therefore, each cantilever can be regarded as a piezoelectric nanogenerator module. This solution integrates at least four piezoelectric nanogenerator modules, thereby increasing the overall output. Furthermore, this solution overturns 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 solution, 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 generated by the piezoelectric power generation unit structure designed in this solution helps to reduce the resonance phenomenon of the vibration system and improve the stability and performance of the system. In particular, its application in wireless sensing systems greatly improves the stability of the nanogenerator and provides high performance.

[0012] Furthermore, an upper end cover and a lower end cover are fixed to the upper and lower ends of the shell respectively, and a glass fiber coupling is installed in 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 outer periphery of 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 form 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 its north pole on top and its south pole on the bottom; the floating magnet has its south pole on top and its north pole on the bottom.

[0017] Beneficial effect: The fixed magnet and the suspended magnet repel each other, so that the generated magnetic flux lines 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 adhered and fixed to the upper surface of the fixed magnet, the first copper foil layer is adhered to the upper surface of the first gasket, the polytetrafluoroethylene film is adhered to the upper surface of the first copper foil layer, the second copper foil layer is adhered to the lower surface of the second gasket, and the second gasket is adhered 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: By pasting the first gasket and the first copper foil layer to form an electrode, the first copper foil layer is then pasted and fixed to the polytetrafluoroethylene film to serve as the lower friction layer; the second gasket and the second copper foil layer are pasted to serve as both the upper friction layer and the electrode, so that when the upper friction layer and the lower friction layer generate up and down movements through the 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, applied to the above-mentioned hybrid nanogenerator, includes 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, 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 capacitive 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 an 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 an 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 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.

[0022] Beneficial effects: In the piezoelectric power generation unit management circuit, four transistors 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, and 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, which are responsible for rectifying the positive half-cycle and 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;

[0024] The friction 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 friction power generation unit respectively, 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 with the energy storage capacitor to achieve voltage doubling rectification and simultaneously feed the energy storage capacitor, thereby enhancing the simplicity and scalability of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of an explosion of a hybrid nanogenerator according to an embodiment of the present invention;

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

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

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

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

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

[0032] Figure 7 Schematic diagram of the power management circuit of the 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. The shell 2 is cylindrical in this application, and an upper end cover 1 and a lower end cover 10 are respectively provided at both ends of the shell 2. A circular hole is opened in the center of the upper end cover 1 and the lower end cover 10, and a glass fiber coupling 7 passes through the circular hole, and the glass fiber coupling 7 is fixed at the central circular hole of the upper end cover 1 and the lower end cover 10 by a snap.

[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. The first gasket and the second gasket are made of stainless steel, that is, the first gasket and the second gasket are also called the first stainless steel gasket 6 and the second stainless steel gasket 5. The piezoelectric power generation unit includes at least four cantilevers 3 and a disk. One end of the cantilever 3 is fixed to the disk, and a mass block is placed on the upper surface of the other end. The center of the disk is connected to a glass fiber coupling 7. The inner surface 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, with the induction coil 8 from bottom to top, the first stainless steel gasket 6, the first copper foil layer, and the polytetrafluoroethylene film are arranged in sequence. 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. In this way, 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, through the above-mentioned connection method, the electromagnetic power generation unit, the friction power generation unit and the piezoelectric power generation unit are fixed inside the shell 2.

[0039] As for the working principles of the above-mentioned electromagnetic power generation unit, friction power generation unit and piezoelectric power generation unit, first, 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 electrons to flow, forming 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 at the top and the S pole at the bottom, and the suspended magnet 4 has the S pole at the top and the N pole at the bottom. The generated magnetic lines of force enter from the S pole and exit from the N pole. When the suspended magnet 4 moves toward the direction of approaching the induction coil 8, the magnetic field strength increases. According to Lenz's law and the right-hand rule, an induced current is generated from left to right in the induction coil 8 at this time (the left and right directions are based on looking down at the induction coil 8). When the suspended magnet 4 moves away from the induction coil 8, an induced current is generated from right to left.

[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 upper surface of the first stainless steel gasket 6 is glued with a first copper foil layer as an electrode; a polytetrafluoroethylene film is glued on the upper surface of the first copper foil layer as a lower friction layer; the lower surface of the second stainless steel gasket 5 is glued with a second copper foil layer 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 lower electronegativity to the material with higher electronegativity. As a result, 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 in FIG, when the levitation magnet 4 starts to move upward, the second copper foil layer separates from the polytetrafluoroethylene film, forming a small air gap between the two and generating a potential difference 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 will flow from the first copper foil layer to the second copper foil layer; Figure 5 As shown in the figure, when the second copper foil layer moves to its 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 solution, 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 conditions 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. This mismatch in charge distribution will generate an electric field, and eventually 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 electromagnetic power generation unit, the friction power generation unit, and the piezoelectric power generation unit, the overall power generation process is as follows:

[0044] Phase 1: If 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, when the hybrid nanogenerator is stimulated, the levitation magnet 4 moves downward, the magnetic flux passing through the induction coil 8 increases, and an induced current is generated in the induction coil 8, 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 upper surface and negative on the lower surface). The upper friction layer and the lower friction layer contact 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 levitation magnet 4 moves upward, the magnetic flux passing through the induction coil 8 decreases, and an induced current is generated in the induction coil 8, which flows from the left to the right. The PZT thick film recovers its deformation, and 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, forming a small air gap between them, and a potential difference is generated between the two electrodes, causing electrons to flow from the first copper foil layer to the second copper foil layer.

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

[0048] The fifth stage: 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, flowing 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 upper surface and negative on the lower surface). 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. Electrons flow from the second copper foil layer back to the first copper foil layer, and the subsequent power generation process is repeated in sequence.

[0049] In another embodiment of this 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 four piezoelectric power generation unit management circuits, electromagnetic power generation unit management circuits and friction power generation unit management circuits, 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 peaks to extract capacitive 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, such as 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; wherein the four transistors are symmetrically connected, and an NPN transistor and a PNP transistor on the right side of the symmetry axis form a control switch for the negative half cycle, and an NPN transistor and a PNP transistor on the left side of the symmetry axis form 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, there are two energy storage capacitors, 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. 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 negative half cycle of the AC signal in the friction power generation unit respectively. 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 generating unit (with Figure 7 Take PEG1 as an example): In the initial stage, PEG1 is in the positive half cycle, first charging the small capacitor C1 through the base and emitter of NPN transistor Q4. When the voltage of PEG1 reaches the conduction voltage of diode D1, it starts to charge the energy storage capacitor C store1 Charging; When the vibration displacement of PEG1 reaches its peak, the emitter junction of PNP transistor Q1 turns on, and its collector immediately connects to the base of NPN transistor Q2. Current flows in, turning on NPN transistor Q2. This triggers LC resonance between inductor L1 and the inherent capacitance within the piezoelectric generator, extracting energy from the inherent capacitance into inductor L1. The same process occurs during the negative half-cycle, with PNP transistor Q3 turning on, triggering LC resonance.

[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 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 solution, the piezoelectric power generation unit management circuit is based on the P-SSHI topology 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 feed the energy storage capacitor, 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 are not described in detail here. Ordinary technicians in the field are aware of all common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the field can improve and implement this scheme in combination with their own abilities under the inspiration given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the 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 variations and improvements can be made, which should also be regarded as the scope of protection of the present invention. 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 by: 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 housing are connected by a glass fiber coupling; a friction power generation unit, an electromagnetic power generation unit, and a piezoelectric power generation unit are sequentially installed on the glass fiber coupling relative to the bottom end of the housing; The piezoelectric power generation unit includes at least four cantilevers and a disk, one end of the cantilever is fixed to the disk, and a mass block is placed on the upper surface of the other end; the center of the disk is connected to a glass fiber coupling, and the inner side of the upper surface of the four cantilevers is covered with PZT material; 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 set between the fixed magnet and the suspension magnet. 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.

2. The 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. A glass fiber coupling is installed at the center of the upper and lower end covers through buckles, and the glass fiber coupling passes through the upper and lower end covers.

3. The hybrid nanogenerator according to claim 2, characterized in that: The fixed magnet has its N pole on top and its S pole on bottom; the floating magnet has its S pole on top and its N pole on bottom.

4. A power management circuit for a hybrid nanogenerator, applied to a hybrid nanogenerator as claimed in any one of claims 1 to 3, 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. 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 capacitive 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.

5. The power management circuit of a hybrid nanogenerator according to claim 4, characterized in that: The piezoelectric power generation unit management circuit includes two NPN transistors, two PNP transistors, a small capacitor, and two diodes. The at least four piezoelectric power generation unit management circuits adopt a P-SSHI topology structure; wherein the four transistors are connected symmetrically, an NPN transistor and a PNP transistor on the right side of the symmetry axis form a control switch for the negative half-cycle, and an NPN transistor and a PNP transistor on the left side of the symmetry axis form 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 and negative half-cycles of the AC signal generated by the piezoelectric unit.

6. The power management circuit of a hybrid nanogenerator according to claim 5, characterized in that: The electromagnetic power generation unit management circuit includes two diodes, which are responsible for rectifying the positive half-cycle and 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 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 respectively, and the two diodes are also connected to the energy storage capacitor.

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