Electromagnetic vibration energy acquisition circuit and equipment based on low-ripple split capacitor

Abstract

The invention discloses an electromagnetic vibration energy acquisition circuit based on a low-ripple split capacitor and electronic equipment, and the circuit comprises a rectification and polarity detection activation unit which is connected with an electromagnetic generator and is used for carrying out the rectification of alternating current inputted by the electromagnetic generator, and activating a boost chopping conversion unit and a split capacitor unit through the detection of the polarity of the alternating current; the inductive current control unit is used for detecting the inductive current and limiting the inductive current in a preset interval so as to control the working state of the boost chopping conversion unit; the boost chopping conversion unit comprises a first boost chopping conversion unit, a second boost chopping conversion unit and a rectifier diode module, and the structures of the first boost chopping conversion unit and the second boost chopping conversion unit are in mirror symmetry; the split capacitor unit is used for boosting the charging and discharging process of the chopping conversion unit so as to generate positive rail voltage and negative rail voltage at the two ends of the split capacitor unit; and the load is used for receiving the stable direct-current voltage output by the split capacitor unit and supplying power to external equipment.

Description

Technical Field

[0001] The present application relates to the field of electric energy collection technology, and in particular to an electromagnetic vibration energy collection circuit and electronic equipment based on a low ripple split capacitor. Background Art

[0002] With the development of wireless sensor networks and the Internet of Things, electromagnetic vibration energy harvesting technology has gradually attracted attention as a power supply method that does not require battery replacement. Electromagnetic vibration energy harvesting circuits can capture the kinetic energy of speed changes in the environment and convert it into usable electrical energy, thereby powering low-power electronic devices.

[0003] At present, the electromagnetic vibration energy harvesting circuit in the related technology has large ripple at the interface during the boost and rectification process, which will lead to more harmonic components at the interface, thus affecting the normal operation of the power supply equipment. Under low-intensity vibration conditions, the energy conversion efficiency of the existing circuit is low and it is difficult to meet the continuous power supply needs. Summary of the invention

[0004] The purpose of this application is to provide an electromagnetic vibration energy harvesting circuit and electronic equipment based on a low ripple split capacitor, aiming to solve at least one of the above problems.

[0005] In a first aspect, an embodiment of the present application provides an electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor, which is used to harvest energy from an electromagnetic generator. The electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor includes: a rectification and polarity detection activation unit, an inductor current control unit, a boost chopper conversion unit, a split capacitor unit, and a load; The rectification and polarity detection activation unit is connected to the electromagnetic generator, and is used to rectify the alternating current input by the electromagnetic generator, and activate the boost chopper conversion unit and the split capacitor unit by detecting the polarity of the alternating current; The inductor current control unit is used to control the working state of the boost chopper conversion unit by detecting the inductor current and limiting the inductor current to a preset interval; The boost chopper conversion unit comprises a first boost chopper conversion unit, a second boost chopper conversion unit and a rectifier diode module, and the structures of the first boost chopper conversion unit and the second boost chopper conversion unit are mirror-symmetrical; The split capacitor unit is used in the charging and discharging process of the boost chopper conversion unit to generate a positive rail voltage and a negative rail voltage at both ends of the split capacitor unit; The load is used to receive the stable DC voltage output by the split capacitor unit to power external devices.

[0006] In one embodiment, the rectifier diode module includes a first rectifier diode and a second rectifier diode; the first boost chopper conversion unit includes a first inductor, a first switch tube and a first diode; the second boost chopper conversion unit includes a second inductor, a second switch tube and a second diode.

[0007] In one embodiment, the anode of the first rectifying diode is connected to one end of the electromagnetic generator, and the cathode of the first rectifying diode is connected to the first inductor; An anode of the second rectifying diode is connected to the other end of the electromagnetic generator, and a cathode of the second rectifying diode is connected to the second inductor.

[0008] In one embodiment, the first rectifying diode and the second rectifying diode are used to rectify the alternating current generated by the electromagnetic generator; The first rectifier diode and the second rectifier diode are also used to activate the first switch tube and the second switch tube to transmit the electric energy collected by the electromagnetic vibration energy harvesting circuit based on the low ripple split capacitor to the load.

[0009] In one embodiment, the split capacitor unit includes a first capacitor and a second capacitor; The first capacitor is connected to the first boost chopper conversion unit, and the second capacitor is connected to the second boost chopper conversion unit; The first capacitor and the second capacitor are used to compensate for current fluctuations in the first inductor and the second inductor; The split capacitor unit is also used to generate a positive rail voltage and a negative rail voltage between the first capacitor and the second capacitor.

[0010] In one embodiment, the load includes a first load resistor and a second load resistor; One end of the first load resistor is connected to the first capacitor, and one end of the second load resistor is connected to the second capacitor; The other end of the first load resistor and the other end of the second load resistor are respectively connected to a power-consuming device to provide a positive rail voltage and a negative rail voltage to the power-consuming device.

[0011] In one embodiment, the rectifier diode module includes a first rectifier diode and a second rectifier diode; the first boost chopper conversion unit includes a first transformer, a first switch tube and a first diode; the second boost chopper conversion unit includes a second transformer, a second switch tube and a second diode.

[0012] In one embodiment, the primary winding of the first transformer forms a third inductor, and the primary winding of the second transformer forms a fourth inductor; The secondary winding of the first transformer forms a fifth inductor, and the secondary winding of the second transformer forms a sixth inductor.

[0013] In one embodiment, the third inductor and the fifth inductor have opposite winding directions, and the fourth inductor and the sixth inductor have opposite winding directions.

[0014] In a second aspect, an embodiment of the present application provides an electronic device, including an electromagnetic generator and an electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor as described in the first aspect.

[0015] The beneficial effect of the embodiment of the present application is that the current ripple in the inductor inside the electromagnetic generator is significantly reduced by compensating the inductor current fluctuation by splitting the capacitor unit, and the boost function in the AC-DC conversion process is realized, and the load voltage can be both positive and negative and stable within the usable range. The smoothing of the inductor current also reduces harmonic interference, optimizes the dynamic performance of the mechanical part of the electromagnetic generator, and effectively improves the stability and reliability of the entire system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a circuit diagram of an electromagnetic generator provided by the relevant technology.

[0017] Figure 2 It is a schematic diagram of an electromagnetic vibration energy harvesting circuit module based on a low ripple split capacitor provided in an embodiment of the present application.

[0018] Figure 3 It is a schematic diagram of an electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor provided in an embodiment of the present application.

[0019] Figure 4 It is a schematic diagram of current and voltage waveforms of the electromagnetic vibration energy harvesting circuit provided in an embodiment of the present application.

[0020] Figure 5 This is a schematic diagram of an electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor provided in another embodiment of the present application.

[0021] Figure 6 It is a schematic diagram of an electronic device module provided in an embodiment of the present application.

[0022] Main component symbols DETAILED DESCRIPTION

[0023] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present application more clearly understood, the present application 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 application and are not used to limit the present application.

[0024] Electromagnetic generator (EMG), as a vibration energy harvesting device, is widely used to convert the kinetic energy of speed changes in the environment into electrical energy, providing stable energy support for small IoT devices, etc. This energy harvesting method can not only significantly extend the operating time of the device, but also reduce the dependence on traditional batteries, thereby improving the sustainability of the device.

[0025] Electromagnetic vibration energy harvesting systems usually consist of a mechanical part and an electrical part. The main function of the mechanical part is to obtain kinetic energy from the vibration source and convert the kinetic energy into electrical energy through an electromagnetic transducer. The core principle of the electromagnetic transducer is electromagnetic induction: the relative movement of the vibrating mass block causes relative displacement between the magnet and the coil, thereby inducing an electromotive force in the coil. The mechanical part can be equivalent to a second-order mass-spring-damper system, which consists of a vibrating mass block, a spring, a damper, and an external force source. The main parameters include the organic-electrical coupling coefficient, the self-inductance and resistance of the self-inductance coil, etc. In addition, the electrical part will introduce an electrical damping effect to the mechanical part, which changes the dynamic performance of the mechanical system to a certain extent.

[0026] The main function of the electrical part is to receive the output energy of the electromagnetic transducer and transfer it to the load through the circuit. Since the electrical energy output by the electromagnetic transducer is usually alternating current, it needs to be converted into direct current through an AC-DC converter for use by the load. However, although the existing passive rectification methods (such as half-bridge rectification or full-bridge rectification) have simple circuits, they cannot achieve the boost function, which limits their application scope.

[0027] Figure 1 It is a circuit diagram of an electromagnetic generator provided by the related technology. Figure 1 As shown, the electromagnetic transducer can be equivalent to a second-order mass-spring-damper system, whose main components include: vibration mass M, spring with spring stiffness coefficient K, and damping D. The main parameters include: external force source f(t), absolute displacement x(t) of the mass block, electromechanical coupling coefficient Kem, mechanical motion induced electromotive force Vem, self-inductance Lem of the self-inductance coil, and series equivalent resistance Rem of the coil.

[0028] Electromagnetic generators (EMGs) usually output higher currents, but the voltage is generally lower. To solve the boost problem, current research mainly uses the self-inductance of electromagnetic transducers or external series inductance to achieve boost conversion through current discontinuous conduction mode (DCM) or critical conduction mode (CRM). However, this method has significant defects in practical applications. First, a large current ripple will be generated in the internal inductance of the electromagnetic generator. These ripples will introduce a large number of harmonics due to the electromechanical coupling effect, which seriously affects the dynamic performance of the mechanical part. Secondly, the boost function requires inductor current fluctuations, while the input inductance of the electromagnetic transducer is more suitable for the working characteristics of small current ripples, and there is an obvious conflict between the two. The bottleneck of the current technology is how to effectively reduce the current ripple of the internal inductance of the electromagnetic generator while achieving the boost function. This is not only related to the efficiency of the circuit, but also involves key issues such as reducing harmonic interference and optimizing the performance of the mechanical part.

[0029] Therefore, the embodiment of the present application provides an electromagnetic vibration energy harvesting circuit and electronic device based on a low-ripple split capacitor, which significantly reduces the current ripple in the inductor inside the electromagnetic generator through the compensation effect of the split capacitor unit on the inductor current fluctuation, and realizes the boost function in the AC-DC conversion process, and makes the load voltage both positive and negative, and stable within the usable range. The smoothing of the inductor current also reduces harmonic interference, optimizes the dynamic performance of the mechanical part of the electromagnetic generator, and effectively improves the stability and reliability of the entire system.

[0030] Figure 2 Schematic diagram of an electromagnetic vibration energy harvesting circuit module based on a low ripple split capacitor provided in an embodiment of the present application. Figure 2 As shown, the electromagnetic vibration energy harvesting circuit 10 based on low ripple split capacitors includes at least the following parts: a rectification and polarity detection activation unit 11, an inductor current control unit 13, a boost chopper conversion unit 12, a split capacitor unit 14 and a load 15. The electromagnetic vibration energy harvesting circuit 10 based on low ripple split capacitors is connected to an electromagnetic generator 20.

[0031] In the embodiment of the present application, the electromagnetic vibration energy harvesting circuit 10 based on the low ripple split capacitor is used to harvest energy from the electromagnetic generator 20 .

[0032] In the embodiment of the present application, the rectification and polarity detection activation unit 11 is connected to the electromagnetic generator 20, and is used to rectify the alternating current input by the electromagnetic generator 20, and activate the boost chopper conversion unit 14 and the split capacitor unit 14 by detecting the polarity of the alternating current.

[0033] Specifically, the rectification and polarity detection activation unit 11 performs full-wave rectification on the AC signal output by the electromagnetic generator 20 through the rectifier diode included therein, and converts the positive and negative alternating AC power into a single-direction DC power. At the same time, the unit detects the polarity change of the input signal, and when the signal polarity reversal is detected, an activation signal is sent to drive the boost chopper conversion unit 12 and the split capacitor unit 14 to work.

[0034] It can be understood that the core function of the rectification and polarity detection activation unit 11 is to quickly respond to the polarity change of the output signal of the electromagnetic generator 20 to ensure that the boost chopper conversion unit 12 can be put into operation in time, improve the energy conversion efficiency, and smooth the output voltage through the split capacitor 14.

[0035] In the embodiment of the present application, the inductor current control unit 13 is used to control the working state of the boost chopper conversion unit 12 by detecting the inductor current and limiting the inductor current to a preset interval.

[0036] Specifically, the inductor current control unit 13 limits the inductor current by detecting the inductor current value in the boost chopper conversion unit 12 and using the set upper and lower thresholds. When the current exceeds the upper threshold, the inductor current control unit 13 controls the switch tube to be turned off to stop the energy inflow; when the current is lower than the lower threshold, the switch tube is turned on again to continue energy collection.

[0037] It can be understood that the inductor current control unit 13 not only protects the circuit components from overcurrent damage through an effective current limiting mechanism, but also ensures the stability of the circuit output voltage and optimizes the conversion process of electromagnetic energy.

[0038] In the embodiment of the present application, the boost chopper conversion unit 12 includes a first boost chopper conversion unit and a second boost chopper conversion unit, and the structures of the first boost chopper conversion unit and the second boost chopper conversion unit are mirror-symmetrical.

[0039] Specifically, the first boost chopper conversion unit of the boost chopper conversion unit 12 is composed of an inductor, a switch tube and a diode, and the structure of the second boost chopper conversion unit is mirror-symmetrical to the first circuit. The two circuits process the positive and negative half-cycle signals output by the electromagnetic generator 20 respectively to realize the dual-rail boost function.

[0040] It can be understood that the mirror-symmetrical structure design of the boost chopper conversion unit 12 reduces the complexity of circuit design and implementation, while improving the symmetry and efficiency of the circuit, enabling it to stably output positive rail voltage and negative rail voltage to adapt to various load requirements.

[0041] In the embodiment of the present application, the split capacitor unit 14 is used in the charging and discharging process of the boost chopper conversion unit 12 to generate a positive rail voltage and a negative rail voltage across the split capacitor unit 13 .

[0042] Specifically, the split capacitor unit 14 includes two capacitors connected in series, which are used to store the energy output by the boost chopper conversion unit 12 and balance between the positive and negative voltage rails. Through the charging and discharging process of the capacitor, the output current is further smoothed to provide a stable positive rail and negative rail DC voltage.

[0043] It can be understood that the split capacitor unit 14 can not only reduce the output voltage ripple, but also form a potential difference between the positive and negative voltage rails, providing direct support for the dual-rail load, thereby enhancing the applicability of the circuit.

[0044] In an embodiment of the present application, the load 15 is used to receive the stable DC voltage output by the split capacitor unit to power an external device.

[0045] Specifically, the load 15 is composed of two load resistors, which are respectively connected to the positive rail and negative rail voltage output terminals of the split capacitor unit 14, and are used to provide a stable DC voltage for external electrical equipment to meet its normal operation requirements.

[0046] It can be understood that the load 15 is designed to receive a stable voltage that has been rectified, boosted and smoothed, and its configuration is flexible and can be adjusted according to the requirements of external equipment to adapt to equipment application scenarios with different power consumption and voltage ranges.

[0047] Please also read Figure 3 , Figure 3 It is a schematic diagram of an electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor provided in an embodiment of the present application.

[0048] In the embodiment of the present application, the rectifier diode module includes a first rectifier diode D3 and a second rectifier diode D4.

[0049] Specifically, in the embodiment of the present application, the first rectifier diode D3 and the second rectifier diode D4 in the rectifier diode module are used to process the positive half-cycle and negative half-cycle AC signals output by the electromagnetic generator 20, respectively. Through the rectification action, the alternating signal is converted into a DC signal to ensure that the subsequent circuit module can work stably. At the same time, the first rectifier diode D3 and the second rectifier diode D4 activate the first switch tube Q1 and the second switch tube Q2 by turning on the corresponding boost chopper conversion circuit to achieve efficient energy transmission.

[0050] It can be understood that the first rectifier diode D3 and the second rectifier diode D4 in the rectifier diode module not only perform the rectification function, but also play a control and driving role. The design realizes high integration of the circuit, reduces the complexity of the external control signal, and improves the response speed and energy conversion efficiency of the overall system.

[0051] In the embodiment of the present application, the first boost chopper conversion unit includes a first inductor L1, a first switch tube Q1 and a first diode D1. The second boost chopper conversion unit includes a second inductor L2, a second switch tube Q2 and a second diode D2.

[0052] Specifically, the first boost chopper conversion unit is composed of a first inductor L1, a first switch tube Q1 and a first diode D1. When the first rectifier diode D3 is turned on, the first inductor L1 stores the energy of the electromagnetic generator 20, and then transfers the energy to the first capacitor C1 through the switching action of the first switch tube Q1 and the unidirectional conduction characteristic of the first diode D1.

[0053] It is understandable that the core function of the first boost chopper conversion unit is boosting and energy transfer. Through reasonable inductor design and high-frequency control of the switch tube, the circuit can achieve a stable increase in output voltage under low input voltage conditions, providing sufficient power support for the split capacitor unit 14.

[0054] In the embodiment of the present application, the anode of the first rectifier diode D3 is connected to one end of the electromagnetic generator 20, and the cathode of the first rectifier diode D3 is connected to the first inductor L1. The anode of the second rectifier diode D4 is connected to the other end of the electromagnetic generator 20, and the cathode of the second rectifier diode D4 is connected to the second inductor L2.

[0055] In the embodiment of the present application, the first rectifying diode D3 and the second rectifying diode D4 are used to rectify the alternating current generated by the electromagnetic generator 20. The first rectifying diode D3 and the second rectifying diode D4 are also used to activate the first switch tube Q1 and the second switch tube Q2 to transmit the electric energy collected by the electromagnetic vibration energy harvesting circuit 10 based on the low ripple split capacitor to the load 15.

[0056] In an embodiment of the present application, the split capacitor unit 14 includes a first capacitor C1 and a second capacitor C2. The first capacitor C1 is connected to the first boost chopper conversion unit, and the second capacitor C2 is connected to the second boost chopper conversion unit. The first capacitor C1 and the second capacitor C2 are used to compensate for current fluctuations in the first inductor L1 and the second inductor L2. The split capacitor unit 14 is also used to generate a positive rail voltage and a negative rail voltage between the first capacitor C1 and the second capacitor C2.

[0057] Specifically, the first capacitor C1 and the second capacitor C2 in the split capacitor unit 14 are respectively connected to the first boost chopper conversion unit and the second boost chopper conversion unit, for smoothing the fluctuation of the inductor current, and generating a positive rail voltage and a negative rail voltage through the voltage division between the capacitors. These voltages are directly supplied to the load 15 to form a stable DC power supply.

[0058] It can be understood that the split capacitor unit 14 not only improves the output voltage quality of the circuit through energy storage and smoothing functions, but also significantly reduces the impact of ripple current on electrical equipment, providing a technical basis for the application expansion of electromagnetic vibration energy harvesting circuits.

[0059] In the embodiment of the present application, the load 15 includes a first load resistor RL1 and a second load resistor RL2. One end of the first load resistor RL1 is connected to the first capacitor C1, and one end of the second load resistor RL2 is connected to the second capacitor C2. The other end of the first load resistor RL1 and the other end of the second load resistor RL2 are respectively connected to the power-consuming device to provide the positive rail voltage and the negative rail voltage to the power-consuming device.

[0060] Specifically, the first load resistor RL1 and the second load resistor RL2 in the load 15 are respectively connected to the output ends of the first capacitor C1 and the second capacitor C2 to form a symmetrical load structure. The positive rail voltage and negative rail voltage finally output by the load 15 provide a reliable dual-rail DC power supply for the electrical equipment to meet the diverse application requirements.

[0061] It can be understood that the design of load 15 takes into account both stability and adaptability. Through reasonable resistance configuration and dual-rail voltage output, it ensures that the electrical equipment can operate normally under different load conditions, further improving the practicality and reliability of the electromagnetic vibration energy harvesting system.

[0062] Figure 4 Schematic diagram of the current and voltage waveforms of the electromagnetic vibration energy harvesting circuit provided in the embodiment of the present application. Figure 4 .

[0063] In this embodiment, the electromagnetic vibration energy harvesting circuit 10 based on the low ripple split capacitor realizes stable operation under the positive and negative polarities of the input electromotive force Vem through symmetrical design. Figure 4 As shown, the circuit has two switching modes when Vem is positive, namely the switch-on stage [t1, t2] and the switch-off stage [t2, t3]. Since the capacitance of the first capacitor C1 and the second capacitor C2 is relatively large, the voltage thereof remains basically stable within a switching cycle, thereby effectively compensating the ripple current of the circuit.

[0064] In the switch-on phase [t1, t2], the first switch tube Q1 is turned on, and the energy output by the electromagnetic generator 20 is transmitted to the first inductor L1 through its internal inductor Lem and resistor Rem via the first diode D1. At this time, the current iL1 of the first inductor L1 is in a linear rising state, and its rising slope is (VC1+VC2) / L1. In this process, the effects of the first capacitor C1 and the second capacitor C2 are apparent: their currents iC1 and iC2 gradually decrease from positive values ​​until they flow in the opposite direction, thereby compensating for the current of the first inductor L1 and maintaining its continuous rise. This compensation mechanism reduces the ripple amplitude of the output current iem of the inductor Lem inside the electromagnetic generator. When the inductor current reaches the preset second threshold (i.e., time t2), the first switch tube Q1 is triggered to be cut off, and the circuit enters the next stage.

[0065] In the switch cut-off stage [t2, t3], the first switch tube Q1 is cut off, and the energy stored in the first inductor L1 is transferred to the load through the freewheeling first diode D1. At this time, the current iL1 of the inductor L1 decreases linearly, and its decreasing slope is VC2 / L1. In this stage, the second capacitor C2 is connected in series with the inductor Lem inside the electromagnetic generator, and the current in the split capacitor gradually changes from the negative maximum value to the positive maximum value, thereby further compensating for the fluctuation of the current of the first inductor L1. When the inductor current drops to the first threshold value (usually set to zero) (i.e., time t3), the trigger switch tube Q1 is turned on again, and the circuit re-enters the conduction stage [t1, t2].

[0066] Due to the symmetry of the circuit, when the input electromotive force Vem is negative, the second boost chopper conversion unit enters the activated working state, and the first boost chopper conversion unit stops working. The working principle of the second boost chopper conversion unit is the same as that of the first boost chopper conversion unit. Through the energy storage and compensation of the split capacitor, the circuit can be operated alternately under positive and negative polarity conditions.

[0067] The key to the stable operation of the electromagnetic generator under low ripple conditions lies in the reasonable configuration of the split capacitors, the first capacitor C1 and the second capacitor C2. In the switch-on stage, the equivalent capacitance connected in parallel across the inductor L1 is the series connection of the first capacitor C1 and the second capacitor C2; while in the switch-off stage, the equivalent capacitance connected in parallel across the inductor L1 is only the second capacitor C2. This dynamic capacitor configuration optimizes the compensation effect of current fluctuations. By reasonably setting the first threshold and the second threshold of the inductor current, the circuit can minimize ripple and maximize efficiency. Among them, the first threshold is set to zero to ensure that the current rises steadily from the initial state when the switch tube is turned on; the second threshold is optimized according to the energy demand and load characteristics of the system to balance the rise and fall of the current.

[0068] In summary, through the combined design of split capacitors and dual-rail Boost circuits (i.e., the first boost chopper conversion unit and the second boost chopper conversion unit), the ripple of the inductor Lem inside the electromagnetic generator can be effectively smoothed, thereby achieving efficient collection and stable transmission of electromagnetic energy. This design works alternately under positive and negative polarities, can provide a stable dual-rail DC voltage for the load, and is suitable for a variety of application scenarios.

[0069] Figure 5 This is a schematic diagram of an electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor provided in another embodiment of the present application.

[0070] In the embodiment of the present application, the rectifier diode module includes a first rectifier diode D3 and a second rectifier diode D4. The first boost chopper conversion unit includes a first transformer T1, a first switch tube Q1 and a first diode D1. The second boost chopper conversion unit includes a second transformer T2, a second switch tube Q2 and a second diode D2.

[0071] Specifically, the rectifier diode module includes a first rectifier diode D3 and a second rectifier diode D4, which are respectively connected to the electromagnetic generator 20, and are used to rectify the AC power output by the electromagnetic generator and activate the boost chopper conversion unit. The first boost chopper conversion unit is composed of a first transformer T1, a first switch tube Q1 and a first diode D1; the second boost chopper conversion unit is composed of a second transformer T2, a second switch tube Q2 and a second diode D2.

[0072] In the embodiment of the present application, the primary winding of the first transformer T1 forms a third inductor L3, the primary winding of the second transformer T2 forms a fourth inductor L4, the secondary winding of the first transformer T1 forms a fifth inductor L5, and the secondary winding of the second transformer T2 forms a sixth inductor L6.

[0073] In the embodiment of the present application, the winding directions of the third inductor L3 and the fifth inductor L5 are opposite, and the winding directions of the fourth inductor L4 and the sixth inductor L6 are opposite.

[0074] It can be understood that in this embodiment, a transformer self-excitation based inductor current threshold control circuit is provided, which realizes automatic control of the switch tube through transformer self-excitation feedback, thereby setting the first threshold and the second threshold of the inductor current. Figure 5 As shown, Figure 3 Compared with the circuit in FIG. 1 , this embodiment adopts a transformer structure to replace the traditional first inductor L1 and the second inductor L2, thereby optimizing the circuit performance and simplifying the control design.

[0075] In this circuit, the primary windings of the first transformer T1 and the second transformer T2 form the third inductor L3 and the fourth inductor L4, respectively, and the secondary windings form the fifth inductor L5 and the sixth inductor L6, respectively. The directions of the primary and secondary windings are designed to be opposite to ensure the feedback effect of electromagnetic coupling. Among them, one end of the third inductor L3 and the fifth inductor L5 are connected, and the other end is connected to the cathode of the first rectifier diode D3 and the gate of the first switch tube Q1, respectively, and the fourth inductor L4 and the sixth inductor L6 are connected in a similar manner.

[0076] The working process is as follows: Switching tube conduction stage: When the gate voltage of the first switch tube Q1 is higher than its conduction threshold, the first switch tube Q1 is turned on, and the third inductor L3 on the primary side of the transformer begins to conduct. At this time, the inductor current gradually rises, and the parasitic resistance in the loop causes the slope of the current rise to gradually slow down, while the cathode voltage of the first rectifier diode D3 slowly decreases. Through the electromagnetic coupling of the transformer, the fifth inductor L5 of the feedback winding induces a voltage to provide a gate voltage for the first switch tube Q1. As the feedback voltage gradually decreases, the gate voltage of the first switch tube Q1 gradually decreases until it is lower than the conduction threshold, and the first switch tube Q1 is turned off, thereby setting the second threshold of the inductor current.

[0077] Switching tube cut-off stage: When the first switch tube Q1 is turned off, the primary side inductor third inductor L3 begins to release the stored energy, and the current gradually decreases. When the current drops to zero, that is, reaches the first threshold, the energy stored in the transformer is completely released, and the induced current of the feedback winding fifth inductor L5 is also close to zero. At this stage, the output voltage of the electromagnetic generator is connected in parallel with the series voltage of the first capacitor C1 and the second capacitor C2, so that the gate voltage of the first switch tube Q1 rises rapidly, and the first switch tube Q1 is turned on again, entering the next conduction stage.

[0078] Cyclic working principle: Under positive polarity conditions, the inductor current fluctuates periodically between the first threshold and the second threshold, thereby achieving a boost function. When the input voltage is negative polarity, the second boost chopper conversion unit enters the working state, and the second switch tube Q2 automatically turns on and off under the action of the feedback winding. Its working principle is the same as that under the positive polarity state, but the direction and circuit configuration are symmetrical.

[0079] It can be understood that the control method based on transformer self-excitation realizes automatic control of the first switch tube Q1 and the second switch tube Q2 through the feedback winding, effectively setting the threshold range of the inductor current. While simplifying the switch tube control circuit, this method can automatically adjust the current within the threshold range to ensure stable operation of the circuit and efficiently complete the boost function. Through the innovative design of self-excitation feedback, the technical advantages of the present invention in structural optimization and performance improvement are further reflected.

[0080] Figure 6 It is a schematic diagram of an electronic device module provided in an embodiment of the present application.

[0081] like Figure 6 The electronic device 1 shown includes an electromagnetic vibration energy harvesting circuit 10 based on a low ripple split capacitor and an electromagnetic generator 20 .

[0082] Specifically, the electronic device 1 converts mechanical vibration or other forms of energy into electrical energy through the electromagnetic generator 20. The AC power generated by the electromagnetic generator is first rectified by the rectifier module, and then enters the electromagnetic vibration energy harvesting circuit 10 based on the low ripple split capacitor for processing. The electromagnetic vibration energy harvesting circuit 10 based on the low ripple split capacitor utilizes the split capacitor design and the boost chopper conversion unit to stably convert the input electrical energy into direct current suitable for driving the load.

[0083] It can be understood that the low ripple split capacitor structure greatly smoothes the output current ripple of the electromagnetic generator by introducing a split capacitor unit between the two boost inductors. At the same time, the electromagnetic vibration energy harvesting circuit further optimizes the power harvesting efficiency and output voltage stability by controlling the inductor current mode of the first threshold and the second threshold.

[0084] The electromagnetic vibration energy harvesting circuit 10 and electronic device 1 based on low-ripple split capacitors provided in the embodiments of the present application can utilize the current compensation effect of the split capacitor to effectively reduce the current ripple inside the electromagnetic generator, thereby improving the power generation efficiency. Through the symmetrical dual-rail Boost circuit design, the boost function in the AC-DC conversion process is simultaneously realized, and the load voltage can be both positive and negative, and stable within the usable range. With the help of the transformer self-excitation feedback control mechanism, the switch tube is automatically turned on and off without the need for additional complex control circuits. This design is not only suitable for low-power portable electronic devices, but also for industrial and medical equipment modules that require high energy density.

[0085] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0086] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. An electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor, used to harvest energy from an electromagnetic generator, characterized in that: The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor includes: a rectification and polarity detection activation unit, a boost chopper conversion unit, an inductor current control unit, a split capacitor unit and a load; The rectification and polarity detection activation unit is connected to the electromagnetic generator, and is used to rectify the alternating current input by the electromagnetic generator, and activate the boost chopper conversion unit and the split capacitor unit by detecting the polarity of the alternating current; The inductor current control unit is used to control the working state of the boost chopper conversion unit by detecting the inductor current and limiting the inductor current to a preset interval; The boost chopper conversion unit comprises a first boost chopper conversion unit, a second boost chopper conversion unit and a rectifier diode module, and the structures of the first boost chopper conversion unit and the second boost chopper conversion unit are mirror-symmetrical; The split capacitor unit is used in the charging and discharging process of the boost chopper conversion unit to generate a positive rail voltage and a negative rail voltage at both ends of the split capacitor unit; The load is used to receive the stable DC voltage output by the split capacitor unit to power external devices.

2. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 1, characterized in that: The rectifier diode module includes a first rectifier diode and a second rectifier diode; the first boost chopper conversion unit includes a first inductor, a first switch tube and a first diode; the second boost chopper conversion unit includes a second inductor, a second switch tube and a second diode.

3. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 2 is characterized in that: The anode of the first rectifying diode is connected to one end of the electromagnetic generator, and the cathode of the first rectifying diode is connected to the first inductor; An anode of the second rectifying diode is connected to the other end of the electromagnetic generator, and a cathode of the second rectifying diode is connected to the second inductor.

4. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 3 is characterized in that: The first rectifying diode and the second rectifying diode are used to rectify the alternating current generated by the electromagnetic generator; The first rectifier diode and the second rectifier diode are also used to activate the first switch tube and the second switch tube to transmit the electric energy collected by the electromagnetic vibration energy harvesting circuit based on the low ripple split capacitor to the load.

5. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 3, characterized in that: The split capacitor unit includes a first capacitor and a second capacitor; The first capacitor is connected to the first boost chopper conversion unit, and the second capacitor is connected to the second boost chopper conversion unit; The first capacitor and the second capacitor are used to compensate for current fluctuations in the first inductor and the second inductor; The split capacitor unit is also used to generate a positive rail voltage and a negative rail voltage between the first capacitor and the second capacitor.

6. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 5, characterized in that: The load includes a first load resistor and a second load resistor; One end of the first load resistor is connected to the first capacitor, and one end of the second load resistor is connected to the second capacitor; The other end of the first load resistor and the other end of the second load resistor are respectively connected to an electric device to provide a positive rail voltage and a negative rail voltage to the electric device.

7. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 1, characterized in that: The rectifier diode module includes a first rectifier diode and a second rectifier diode; the first boost chopper conversion unit includes a first transformer, a first switch tube and a first diode; the second boost chopper conversion unit includes a second transformer, a second switch tube and a second diode.

8. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 7, characterized in that: The primary winding of the first transformer forms a third inductor, and the primary winding of the second transformer forms a fourth inductor; The secondary winding of the first transformer forms a fifth inductor, and the secondary winding of the second transformer forms a sixth inductor.

9. The electromagnetic vibration energy harvesting circuit based on low ripple split capacitor according to claim 8, characterized in that: The third inductor and the fifth inductor have opposite winding directions, and the fourth inductor and the sixth inductor have opposite winding directions.

10. An electronic device, characterized in that: It comprises an electromagnetic generator and an electromagnetic vibration energy harvesting circuit based on a low ripple split capacitor as described in any one of claims 1 to 9.

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