A micro-energy cascade collection system for a piezoelectric self-generating device

Abstract

The present invention provides a micro-energy cascade collection system for a piezoelectric self-generating device, comprising a piezoelectric self-generating front-end mechanical device, a charging simulation switch, a first micro-energy collection module, a second micro-energy collection module, a power supply simulation switch and a wireless receiving end module electrically connected in sequence; the charging simulation switch is used to control the conduction between the electric energy input by the piezoelectric self-generating front-end mechanical device and the first micro-energy collection module and the second micro-energy collection module, respectively, and the cascade charging of the first micro-energy collection module and the second micro-energy collection module is realized by setting the preset switching time of the cascade collection energy storage; the first micro-energy collection module and the second micro-energy collection module are respectively used to store electric energy, and convert the stored electric energy into power supply current, respectively, and output it to the power supply simulation switch; the power supply simulation switch supplies power to the wireless receiving end module. The present invention has good time switching effect for charging and power supply, wide application expansibility and high safety and reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of self-generation technology, and in particular to a micro-energy cascade collection system for a piezoelectric self-generation device. Background Art

[0002] Self-generation technology generally includes piezoelectric self-generation and thermoelectric self-generation, which convert various energies in the surrounding environment into electrical energy, thereby driving low-power electronic devices to operate. Nowadays, many smart home wireless switch devices, piezoelectric road devices, and some building wireless intercom devices use self-generation technology. These self-generation devices do not generate much electricity, but meet the application requirements of some specific scenarios, are energy-saving and environmentally friendly, and have the advantages of easy installation and replacement.

[0003] Existing piezoelectric self-generating devices generally include electromagnetic induction magnetic line cutting technology and piezoelectric ceramic technology. The existing piezoelectric self-generating device collection system converts mechanical energy into electrical energy by pressing a mechanical movement, and the micro-energy collection system correspondingly collects and stores the electrical energy generated by the pressing. Taking the electromagnetic induction device cutting magnetic lines as an example to describe the existing self-generating technology, the piezoelectric self-generating technology that generates electrical energy by electromagnetic induction due to the magnetic line cutting movement is to press the mechanical device to change the conductor magnetic field inside the device to generate an induced current, thereby achieving the purpose of converting mechanical energy into electrical energy. However, due to the limitations of the design of this electromagnetic induction self-generating device, even if the electrical energy generated by pressing the mechanical action once is theoretically sufficient, due to the design circuit loss and changes in application scenarios, the self-generating device deployed above often uses the above-mentioned self-generating device. After a period of use, the power generation of the device cannot meet the actual application needs, and the solution needs to be changed, and the user experience is not good.

[0004] Therefore, the existing piezoelectric self-generating device cannot fully collect electrical energy by using multiple pressing actions, and the electrical energy generated by each pressing may be different, which easily leads to large energy storage consumption; at the same time, the application scalability of the piezoelectric self-generating device is poor and the safety and reliability are low. Summary of the invention

[0005] The present invention provides a micro energy cascade collection system for a piezoelectric self-generating device, aiming to solve the problems of large energy storage consumption, poor application scalability and low safety and reliability of the micro energy collection system in the prior art.

[0006] The embodiment of the present invention provides a micro-energy cascade collection system for a piezoelectric self-generating device, comprising a piezoelectric self-generating front-end mechanical device, a charging simulation switch, a first micro-energy collection module, a second micro-energy collection module, a power supply simulation switch, and a wireless receiving end module which are electrically connected in sequence;

[0007] The piezoelectric self-generating front-end mechanical device is used to convert mechanical energy into electrical energy by pressing the mechanical device;

[0008] The charging simulation switch is used to control the conduction between the electric energy input by the piezoelectric self-generating front-end mechanical device and the first micro energy collection module and the second micro energy collection module, respectively, and the cascade charging of the first micro energy collection module and the second micro energy collection module is realized by setting the preset switching time of the cascade collection and energy storage;

[0009] The first micro energy collection module and the second micro energy collection module are respectively used to store the electric energy, and convert the stored electric energy into power supply current, and output it to the power supply analog switch;

[0010] The power supply simulation switch is used to use the power supply current collected by the first micro energy collection module and the second micro energy collection module respectively to power the wireless receiving end module according to the preset power supply time; and the charging and power supply switching functions are performed according to the preset switching time through the charging simulation switch and the power supply simulation switch.

[0011] Preferably, the preset switching time of the charging simulation switch is determined as follows:

[0012] With each pressing of the piezoelectric self-generating front-end mechanical device, the charging simulation switch sequentially conducts the input electric energy of the piezoelectric self-generating front-end mechanical device to the first micro energy collection module or the second micro energy collection module. The conduction time of the first micro energy collection module is set to the length of the pressing stroke of the piezoelectric self-generating front-end mechanical device to complete the switching. The power generation curve when the key switch is pressed is observed. From the waveform diagram captured by the oscilloscope, it is observed that the time required for the rise to reach the maximum charging voltage is the pressing stroke time.

[0013] Preferably, the first micro energy collection module includes a first resistor, a charging capacitor, a power supply capacitor, a step-down chip and a second resistor; the first end of the first resistor is respectively connected to the input end of the charging analog switch and the first end of the charging capacitor, the second end of the first resistor is respectively connected to the second end of the charging capacitor and the input end of the step-down chip, the output end of the step-down chip is respectively connected to the first end of the power supply capacitor and the first end of the second resistor, the second end of the charging capacitor is respectively connected to the ground end of the step-down chip, the first end of the charging capacitor and the second end of the second resistor, the first end of the first resistor serves as the input end of the first micro energy collection module, and the third end of the second resistor serves as the output end of the first micro energy collection module.

[0014] Preferably, the second micro energy collection module includes a first resistor, a charging capacitor, a power supply capacitor, a step-down chip and a second resistor; the first end of the first resistor is respectively connected to the input end of the charging analog switch and the first end of the charging capacitor, the second end of the first resistor is respectively connected to the second end of the charging capacitor and the input end of the step-down chip, the output end of the step-down chip is respectively connected to the first end of the power supply capacitor and the first end of the second resistor, the second end of the charging capacitor is respectively connected to the ground end of the step-down chip, the first end of the charging capacitor and the second end of the second resistor, the first end of the first resistor serves as the input end of the second micro energy collection module, and the third end of the second resistor serves as the output end of the second micro energy collection module.

[0015] Preferably, the switching time of the power supply simulation switch is determined as follows:

[0016] The power supply simulation switch is responsible for outputting the stabilized electric energy of the different first micro energy collection modules and the second micro energy collection modules to the wireless receiving end module; the power supply time is set, and continuous power supply to the back-end application circuit can be achieved through cascading. The switching time of the power supply simulation switch circuit is the power supply duration of the second micro energy collection module.

[0017] Preferably, the switching time of the power supply analog switch is determined by the following expression (1):

[0018] t= (1);

[0019] Wherein, Rout represents the resistance value of the second resistor, Uc represents the circuit operating voltage after the voltage reduction chip is stabilized, and Wc represents the minimum energy required for wirelessly sending a reliable byte packet.

[0020] Preferably, the circuit structure of the first micro energy harvesting module is the same as that of the second micro energy harvesting module.

[0021] Preferably, the step-down chip is a LM2576 chip.

[0022] Compared with the prior art, the beneficial effect of the present invention is that the piezoelectric self-generating front-end mechanical device is used to realize the conversion of mechanical energy into electric energy by pressing the mechanical device; the charging analog switch is used to control the conduction of the electric energy input by the piezoelectric self-generating front-end mechanical device with the first micro energy collection module and the second micro energy collection module respectively, and the cascade charging of the first micro energy collection module and the second micro energy collection module is realized by setting the preset switching time of the cascade collection and energy storage; the first micro energy collection module and the second micro energy collection module are respectively used to store electric energy, and convert the stored electric energy into power supply current respectively, and output it to the power supply analog switch; the power supply analog switch is used to power the wireless receiving end module with the power supply current collected by the first micro energy collection module and the second micro energy collection module according to the preset power supply time; the wireless receiving end module receives the continuous power supply of the micro energy collection module under the action of the discharge analog switch circuit, and performs the switching function of charging and power supply according to the preset switching time through the charging analog switch and the power supply analog switch. In this way, by adding an analog switch after the self-generating device at the front end, an analog switch is also added at the output power end. It is used to support the cascading of two or more existing micro-energy harvesting systems, and supports cascaded energy storage and cascaded power supply. For example, users are accustomed to pressing the switch twice, once for on and once for off; it is used to support that both presses (on and off) can effectively harvest electricity. The new micro-energy cascade harvesting power circuit can harvest more electricity, and at the same time, the cascaded power supply can also meet the changes in user-side electricity consumption. It has good scalability and adapts to a wider range of scenarios. In addition, with the cascaded micro-energy harvesting setting, if one harvesting system fails, the other harvesting system can also work, providing a more reliable backup solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention will be described in detail below in conjunction with the accompanying drawings. The above and other aspects of the present invention will become clearer and easier to understand through the detailed description made in conjunction with the following drawings. In the accompanying drawings:

[0024] Figure 1 It is a module diagram of a micro-energy cascade collection system for a piezoelectric self-generating device provided by an embodiment of the present invention;

[0025] Figure 2 is a circuit diagram of a first micro energy harvesting module provided in an embodiment of the present invention;

[0026] Figure 3 It is a circuit diagram of a second micro energy harvesting module provided in an embodiment of the present invention.

[0027] In the figure, 1. Piezoelectric self-generating front-end mechanical device, 2. Charging simulation switch, 3. First micro energy collection module, 4. Second micro energy collection module, 5. Power supply simulation switch, 6. Wireless receiving end module, 7. Buck chip. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0029] Combined with Figure 1-Figure 3 As shown, an embodiment of the present invention provides a micro-energy cascade collection system for a piezoelectric self-generating device, comprising a piezoelectric self-generating front-end mechanical device 1, a charging simulation switch 2, a first micro-energy collection module 3, a second micro-energy collection module 4, a power supply simulation switch 5 and a wireless receiving end module 6 electrically connected in sequence.

[0030] The piezoelectric self-generating front-end mechanical device 1 is used to convert mechanical energy into electrical energy by pressing the mechanical device.

[0031] The charging simulation switch 2 is used to control the conduction between the electric energy input by the piezoelectric self-generating front-end mechanical device 1 and the first micro energy collection module 3 and the second micro energy collection module 4, respectively. By setting the preset switching time of the cascade collection and energy storage, the cascade charging of the first micro energy collection module 3 and the second micro energy collection module 4 is realized. The charging simulation switch 2 is responsible for controlling the conduction between the electric energy input by the front-end mechanical device and the back-end micro energy collection (electric energy storage) module, and the switching time of the cascade collection and energy storage is set, so that the cascade charging of the subsequent micro energy collection modules can be realized.

[0032] The first micro energy collection module 3 and the second micro energy collection module 4 are used to store the electric energy, and convert the stored electric energy into power supply current, and output it to the power supply analog switch 5. The first micro energy collection module 3 and the second micro energy collection module 4, the circuit mainly includes rectification, filtering, voltage stabilization and storage circuits. The first micro energy collection module 3 and the second micro energy are responsible for storing the electric energy generated by the pressing action of the mechanical device, and then generating a stable power supply current from the stored electric energy through the internal voltage stabilization circuit design, and stably outputting the current to the wireless receiving end module 6, the wireless receiving end module 6 is connected to the actual application equipment to realize the power supply function of the self-generating device.

[0033] The power supply simulation switch 5 is used to power the wireless receiving end module 6 with the power supply current respectively collected by the first micro energy collection module 3 and the second micro energy collection module 4 according to the preset power supply time, and the charging and power supply switching function is performed according to the preset switching time through the charging simulation switch 2 and the power supply simulation switch 5.

[0034] Specifically, by pressing the piezoelectric self-generating front-end mechanically, mechanical energy is converted into electrical energy, the circuit is output to the charging analog switch 2, and the electrical energy is output to the first micro-energy collection module 3 and the second micro-energy collection module 4 respectively through the charging analog switch 2, and the corresponding electrical energy is collected by the first micro-energy collection module 3 and the second micro-energy collection module 4 respectively, and then the stored electrical energy is designed to generate a stable power supply current through the internal voltage stabilizing circuit, and the current is stably output to the wireless receiving end module 6, and the wireless receiving end module 6 is connected to the actual application device to realize the power supply function of the self-generating device. In this way, an analog switch is added after the self-generating device at the front end, and an analog switch is also added at the output power end. It is used to support the cascading of two or more existing micro-energy collection systems, and supports cascade energy storage and cascade power supply. For example, the user is accustomed to pressing the switch twice, once to open and once to close; it is used to support that both pressings (open and close) can effectively collect electrical energy. The new micro-energy cascade power collection circuit can collect more electrical energy, and at the same time, it can also meet the changes in user-side power consumption through cascade power supply, has good scalability, and is more adaptable to a wider range of scenarios. Moreover, a cascaded micro-energy harvesting setup is adopted. If one harvesting system fails, the other harvesting system can also work, providing a more reliable backup solution.

[0035] In this embodiment, the preset switching time of the charging simulation switch 2 is determined as follows:

[0036] With each pressing of the piezoelectric self-generating front-end mechanical device 1, the charging simulation switch 2 sequentially conducts the input electric energy of the piezoelectric self-generating front-end mechanical device 1 with the first micro energy collection module 3 or the second micro energy collection module 4. The conduction time of the first micro energy collection module 3 is set to the length of the pressing stroke of the piezoelectric self-generating front-end mechanical device 1 to complete the switching. The power generation curve when the key switch is pressed is observed. From the waveform diagram captured by the oscilloscope, it is observed that the time required for the rise to reach the maximum charging voltage is the pressing stroke time.

[0037] Specifically, each time the self-generating mechanical device is pressed, the analog switch sequentially conducts the input electrical energy of the mechanical device to a micro energy collection module. The conduction time of the first micro energy collection module 3 is set to the length of the pressing stroke of the mechanical device (the duration of the mechanical device generating electricity) to complete the switching. The pressing stroke can be observed by an oscilloscope, that is, the waveform of the power generation module is tested when it is unloaded, and the power generation curve when the key switch is pressed is observed. From the waveform captured by the oscilloscope, it is observed that the time required to rise when reaching the maximum charging voltage is the pressing stroke time.

[0038] Similarly, the conduction time of the second micro-energy cascade collection module is determined in the same way as the conduction time of the first micro-energy collection module 3. Among them, through each press of the self-generating mechanical device, the analog switch sequentially conducts the input electrical energy of the mechanical device to a micro-energy collection module. The conduction time of the second micro-energy collection module 4 is set to the length of the pressing stroke of the mechanical device (the duration of the mechanical device generating electricity) to complete the switching. The pressing stroke can be observed with an oscilloscope, that is, to test the waveform of the power generation module when it is unloaded, observe the power generation curve when the key switch is pressed, and observe the time required to rise when reaching the maximum power supply voltage from the waveform diagram captured by the oscilloscope, which is the pressing stroke time.

[0039] In this embodiment, the first micro energy collection module 3 includes a first resistor R1, a charging capacitor C1, a power supply capacitor C2, a buck chip 7 and a second resistor Rout; the first end of the first resistor R1 is respectively connected to the input end of the charging simulation switch 2 and the first end of the charging capacitor C1, the second end of the first resistor R1 is respectively connected to the second end of the charging capacitor C1 and the input end of the buck chip 7, the output end of the buck chip 7 is respectively connected to the first end of the power supply capacitor C2 and the first end of the second resistor Rout, the second end of the charging capacitor C1 is respectively connected to the ground end of the buck chip 7, the first end of the charging capacitor C1 and the second end of the second resistor Rout, the first end of the first resistor R1 serves as the input end of the first micro energy collection module 3, and the third end of the second resistor Rout serves as the output end of the first micro energy collection module 3.

[0040] Specifically, the charging simulation is responsible for controlling the conduction between the electric energy input by the front-end mechanical device and the back-end micro-energy collection (electric energy storage) module. The cascade collection requires setting the switching time to realize the cascade charging of the subsequent micro-energy collection modules.

[0041] In this embodiment, the second micro energy collection module 4 includes a first resistor R1, a charging capacitor C1, a power supply capacitor C2, a buck chip 7 and a second resistor Rout; the first end of the first resistor R1 is respectively connected to the input end of the charging simulation switch 2 and the first end of the charging capacitor C1, the second end of the first resistor R1 is respectively connected to the second end of the charging capacitor C1 and the input end of the buck chip 7, the output end of the buck chip 7 is respectively connected to the first end of the power supply capacitor C2 and the first end of the second resistor Rout, the second end of the charging capacitor C1 is respectively connected to the ground end of the buck chip 7, the first end of the charging capacitor C1 and the second end of the second resistor Rout, the first end of the first resistor R1 serves as the input end of the first micro energy collection module 3, and the third end of the second resistor Rout serves as the output end of the second micro energy collection module 4.

[0042] Specifically, the analog switch (power supply) is responsible for outputting the voltage-regulated power from different micro-energy harvesting modules to the wireless receiving module. By setting the power supply time, continuous power supply to the back-end application circuit can be achieved through cascading. The switching time of the back-end analog switch circuit is the power supply duration of the micro-energy harvesting module.

[0043] In this embodiment, the switching time of the power supply simulation switch 5 is determined by the following expression (1):

[0044] t= (1);

[0045] Wherein, Rout represents the resistance value of the second resistor Rout, Uc represents the circuit operating voltage after voltage stabilization by the step-down chip 7, and Wc represents the minimum energy required for wirelessly sending a reliable byte packet.

[0046] Specifically, the power supply analog switch 5 is responsible for outputting the voltage-stabilized electric energy of different micro-energy collection modules to the wireless receiving end module 6. By setting the power supply time, continuous power supply to the back-end application circuit can be achieved through cascading. The switching time of the back-end analog switch circuit is the power supply duration of the first micro-energy collection module 3 or the second micro-energy collection module 4.

[0047] Preferably, =10KΩ,W=220 , Uc=3.3V, then the continuous power supply time can be calculated as

[0048] t = (10000*220* / (3.3*3.3) =200ms.

[0049] In this embodiment, the circuit structure of the first micro energy collection module 3 and the second micro energy collection module 4 is the same.

[0050] In this embodiment, the model of the buck chip 7 is LM2576 chip. LM2576 chip is an efficient and simple buck chip 7, and the output voltage is adjustable and stable.

[0051] The beneficial effects of this embodiment are as follows:

[0052] 1. Overcome the problem that the existing piezoelectric self-generating system is only suitable for application scenarios where the power supply amplitude varies slightly. Because there are many application scenarios for self-generating electricity, the electric energy required for actual application will vary within a certain range, and the existing self-generating mechanical device design is designed based on the maximum electric energy index required by the application, requiring the design of the generated electric energy and the power supply electric energy to be accurately estimated, which will inevitably increase the material cost and design difficulty of the solution. The flexibility of the cascade power supply collection method of the present invention is greatly enhanced, and the self-generating system is applicable to more application scenarios, meeting the certain amplitude variation of power consumption in actual applications, and the performance indicators do not need to be so accurate and harsh, and the difficulty of design and development is greatly reduced.

[0053] For example, if an application scenario needs to send a 5-byte information packet, 220 microjoules of electricity can meet the requirement. However, a new application needs to send 7 bytes, which must generate more than 220 microjoules of electricity to meet the requirement. This requires changes to the front-end power generation mechanical device. The existing power generation method has poor scalability and flexibility. The new method uses cascade power storage and cascade power supply, which can avoid changing the original mechanical design of self-generation and can be better applied to scenarios where the power supply energy needs to change within a certain range.

[0054] 2. It overcomes the problem that the existing piezoelectric self-generating system can only collect electricity once, and cannot make use of the daily habit of turning it on and off twice, and supports collecting electricity twice. The existing self-generating device generates electricity once by pressing the opening action, and the device starts working. After the device is done working, it is pressed again to close the action, and electricity cannot be collected. The new invention uses the familiar opening and closing principle, pressing twice, once to turn the device on and once to turn it off. Through cascading, electricity can be collected twice. Moreover, due to the different speeds and strengths of the pressing actions of different people, the resulting electricity is different, which will also lead to unstable operation of the equipment. The existing cascade method can collect energy by pressing twice, and there is a backup plan for electricity collection. It is rare that the electricity generated cannot meet the application due to different pressing methods.

[0055] 3. Overcome the defects of low safety and reliability of existing piezoelectric self-generating systems. The circuit design of the existing micro-energy harvesting system is in a critical middle position. On the one hand, it receives electrical energy input from the self-generating front-end mechanical device, and on the other hand, it outputs power to the wireless receiving device. If a fault occurs in the middle link of the circuit design of the micro-energy harvesting system, the entire self-generating system will not work, which is not suitable for some application scenarios with relatively high safety requirements. The new micro-energy cascade harvesting system proposed in the present invention is to cascade the two original micro-energy harvesting systems to ensure the backup of the energy storage and power supply system.

[0056] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, article or device. In the absence of more restrictions, an element defined by the sentence "includes a ..." does not exclude the existence of other identical elements in the process, article or device including the element.

[0057] The embodiments of the present invention are described above in conjunction with the accompanying drawings. What is disclosed is only the preferred embodiment of the present invention. However, the present invention is not limited to the above-mentioned specific implementation manner. The above-mentioned specific implementation manner is only illustrative rather than restrictive. Under the enlightenment of the present invention, ordinary technicians in this field can also make many forms and equivalent changes without departing from the scope of protection of the purpose of the present invention and the claims, all of which are within the protection of the present invention.

Claims

1. A micro-energy cascade collection system for a piezoelectric self-generating device, characterized in that: It includes a piezoelectric self-generating front-end mechanical device, a charging simulation switch, a first micro-energy collection module, a second micro-energy collection module, a power supply simulation switch and a wireless receiving end module which are electrically connected in sequence; The piezoelectric self-generating front-end mechanical device is used to convert mechanical energy into electrical energy by pressing the mechanical device; The charging simulation switch is used to control the conduction between the electric energy input by the piezoelectric self-generating front-end mechanical device and the first micro energy collection module and the second micro energy collection module, respectively, and the cascade charging of the first micro energy collection module and the second micro energy collection module is realized by setting the preset switching time of the cascade collection and energy storage; The first micro energy collection module and the second micro energy collection module are respectively used to store the electric energy, and convert the stored electric energy into power supply current, and output it to the power supply analog switch; The power supply simulation switch is used to use the power supply current collected by the first micro energy collection module and the second micro energy collection module to power the wireless receiving end module according to the preset power supply time; the charging and power supply switching functions are performed according to the preset switching time through the charging simulation switch and the power supply simulation switch; The preset switching time of the charging simulation switch is determined as follows: With each pressing of the piezoelectric self-generating front-end mechanical device, the charging simulation switch sequentially conducts the input electric energy of the piezoelectric self-generating front-end mechanical device to the first micro energy collection module or the second micro energy collection module. The conduction time of the first micro energy collection module is set to the length of the pressing stroke of the piezoelectric self-generating front-end mechanical device to complete the switching. The power generation curve when the key switch is pressed is observed. From the waveform diagram captured by the oscilloscope, it is observed that the time required for the rise to reach the maximum charging voltage is the pressing stroke time.

2. The micro energy cascade collection system of the piezoelectric self-generating device according to claim 1, characterized in that: The first micro energy collection module includes a first resistor, a charging capacitor, a power supply capacitor, a step-down chip and a second resistor; the first end of the first resistor is respectively connected to the input end of the charging analog switch and the first end of the charging capacitor, the second end of the first resistor is respectively connected to the second end of the charging capacitor and the input end of the step-down chip, the output end of the step-down chip is respectively connected to the first end of the power supply capacitor and the first end of the second resistor, the second end of the charging capacitor is respectively connected to the ground end of the step-down chip, the first end of the charging capacitor and the second end of the second resistor, the first end of the first resistor serves as the input end of the first micro energy collection module, and the third end of the second resistor serves as the output end of the first micro energy collection module.

3. The micro energy cascade collection system of the piezoelectric self-generating device according to claim 1, characterized in that: The second micro energy collection module includes a first resistor, a charging capacitor, a power supply capacitor, a step-down chip and a second resistor; the first end of the first resistor is respectively connected to the input end of the charging analog switch and the first end of the charging capacitor, the second end of the first resistor is respectively connected to the second end of the charging capacitor and the input end of the step-down chip, the output end of the step-down chip is respectively connected to the first end of the power supply capacitor and the first end of the second resistor, the second end of the charging capacitor is respectively connected to the ground end of the step-down chip, the first end of the charging capacitor and the second end of the second resistor, the first end of the first resistor serves as the input end of the second micro energy collection module, and the third end of the second resistor serves as the output end of the second micro energy collection module.

4. The micro energy cascade collection system of the piezoelectric self-generating device according to claim 2 or 3, characterized in that: The switching time of the power supply simulation switch is determined as follows: The power supply simulation switch is responsible for outputting the stabilized electric energy of the first micro energy collection module and the second micro energy collection module to the wireless receiving end module; the power supply time is set, and continuous power supply to the back-end application circuit can be achieved through cascading. The switching time of the power supply simulation switch circuit is the power supply duration of the second micro energy collection module.

5. The micro energy cascade collection system of the piezoelectric self-generating device according to claim 4, characterized in that: The switching time of the power supply analog switch is determined by the following expression (1): t= （1）； Wherein, Rout represents the resistance value of the second resistor, Uc represents the circuit operating voltage after voltage stabilization by the step-down chip, and Wc represents the minimum energy required for wirelessly sending a reliable byte packet.

6. The micro energy cascade collection system of the piezoelectric self-generating device according to claim 1, characterized in that: The circuit structure of the first micro energy collection module is the same as that of the second micro energy collection module.

7. The micro energy cascade collection system of the piezoelectric self-generating device according to claim 2, characterized in that: The model of the step-down chip is LM2576 chip.

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