阅读说明：本技术 基于并联同步开关电感电路的无线取能ac/dc变换器 (Wireless energy-taking AC/DC converter based on parallel synchronous switch inductance circuit ) 是由 徐长宝 辛明勇 王宇 孟令雯 代奇迹 孙宏棣 田兵 刘仲 吕前程 骆柏锋 王志明 于 2021-06-28 设计创作，主要内容包括：本发明提供一种基于串联同步开关电感电路的无线取能AC/DC变换器,通过设置的正向电压跟随器、反向电压跟随器、正向开关电路、反向开关电路和整流桥组成了并联同步开关电感电路；正向开关电路通过正向电压跟随器输出的电流和压电材料的正向电流对电感所在回路进行正向开关控制；反向开关电路通过压电材料的反向电流对电感所在回路进行反向开关控制；避免了位移传感器和数字控制系统的使用,在对电路进行自功能的同时极大地简化了电路结构。(The invention provides a wireless energy-taking AC/DC converter based on a series synchronous switch inductance circuit, which is characterized in that a parallel synchronous switch inductance circuit is formed by a forward voltage follower, a reverse voltage follower, a forward switch circuit, a reverse switch circuit and a rectifier bridge; the forward switching circuit carries out forward switching control on a loop where the inductor is located through the current output by the forward voltage follower and the forward current of the piezoelectric material; the reverse switch circuit performs reverse switch control on a loop where the inductor is located through reverse current of the piezoelectric material; the use of a displacement sensor and a digital control system is avoided, and the circuit structure is greatly simplified while the self-function of the circuit is carried out.)

1. A wireless energy-taking AC/DC converter based on a parallel synchronous switch inductance circuit is characterized by comprising a piezoelectric material, a forward voltage follower, a reverse voltage follower, a forward switch circuit, a reverse switch circuit, an inductor, a rectifier bridge and a load module; the forward voltage follower, the rectifier bridge and the reverse voltage follower are all connected with the piezoelectric material in parallel; the load module comprises a load and a smoothing capacitor which are connected in parallel; the first end of the load module is connected with the first output end of the rectifier bridge; the second end of the load module is connected with the second output end of the rectifier bridge; the first input end of the forward switch circuit is connected with the forward voltage follower; the second input end and the control end of the forward switch circuit and the first output end and the control end of the reverse switch circuit are both connected with the anode of the piezoelectric material; the second output end of the reverse switch circuit is connected with the reverse voltage follower; the output end of the forward switch circuit and the input end of the reverse switch circuit are both connected with the first end of the inductor; the second end of the inductor is connected with the negative electrode of the piezoelectric material; the forward switching circuit carries out forward switching control on a loop where the inductor is located through the current output by the forward voltage follower and the forward current of the piezoelectric material; and the reverse switch circuit carries out reverse switch control on a loop where the inductor is located through the reverse current of the piezoelectric material.

2. The wireless energy-taking AC/DC converter according to claim 1, wherein the forward voltage follower comprises a first resistor, a first diode and a first capacitor; the first end of the first resistor is connected with the positive electrode of the piezoelectric material; the second end of the first resistor is connected with the anode of the first diode; the negative electrode of the first diode is connected with the first end of the first capacitor; and the second end of the first capacitor is connected with the negative electrode of the piezoelectric material.

3. The wireless energy-taking AC/DC converter according to claim 2, wherein the forward switching circuit comprises a first triode, a second diode and a third diode; the base electrode of the first triode and the anode of the third diode are both connected with the anode of the piezoelectric material; an emitting electrode of the first triode is connected with a negative electrode of the first diode; the collector of the first triode is connected with the anode of the second diode; the cathode of the second diode is connected with the base electrode of the second triode; the collector of the second triode is connected with the cathode of the third diode; and the emitter of the second triode is connected with the first end of the inductor.

4. The wireless energy-taking AC/DC converter according to claim 2, wherein the capacitance value of the first capacitor is 150 pF; the resistance value of the first resistor is 100K omega.

5. The wireless energy-taking AC/DC converter according to claim 1, wherein the smoothing capacitor has a capacitance of 1 uF; the inductance value of the inductor is 10 uH.

6. The wireless energy-taking AC/DC converter according to claim 1, wherein the reverse voltage follower comprises a second capacitor, a fourth diode and a second resistor; the first end of the second resistor is connected with the positive electrode of the piezoelectric material; a second end of the second resistor is connected with a cathode of the fourth diode; the anode of the fourth diode is connected with the first end of the second capacitor; and the second end of the second capacitor is connected with the negative electrode of the piezoelectric material.

7. The wireless energy-taking AC/DC converter according to claim 6, wherein the reverse switching circuit comprises a third triode, a fourth triode, a fifth diode and a sixth diode; the base electrode of the third triode and the cathode of the six diode are both connected with the anode of the piezoelectric material; an emitting electrode of the third triode is connected with a negative electrode of the fourth diode; a collector of the third triode is connected with a cathode of the fifth diode; the anode of the fifth diode is connected with the base electrode of the fourth triode; a collector of the fourth triode is connected with the anode of the sixth diode; and the emitter of the fourth triode is connected with the first end of the inductor.

8. The wireless energy-taking AC/DC converter according to claim 6, wherein the capacitance value of the second capacitor is 150 pF; the resistance value of the second resistor is 100K omega.

Technical Field

The invention relates to the technical field of alternating current-direct current conversion circuits, in particular to a wireless energy-taking AC/DC converter based on a parallel synchronous switch inductance circuit.

Background

At present, in an energy management circuit, a series synchronous switch inductance circuit, a parallel synchronous switch inductance circuit and a synchronous charge extraction circuit all use a control switch, and in order to ensure that the circuit can work normally, the action time, the closing time and the energy loss of the switch need to meet the following three requirements: 1) the switching time must be synchronized with the mechanical vibration of the piezoelectric material; 2) the switch closing time needs to be kept about half LC resonance period; 3) the control circuit and the implementation form of the switch are as simple as possible, and the energy loss is as small as possible.

However, in the existing research, the realization of the control switch mainly depends on a displacement sensor, a Digital Signal Processor (DSP), a single chip microcomputer and other digital control systems. Detecting the displacement of the mechanical vibration of the piezoelectric material through a sensor, and controlling the closing time of a switch; the digital control system is used for controlling the on-off time of the switch, so that the requirements of the first two points can be well met. However, the power loss of the displacement sensor and the digital control system is generally far larger than the electric power which can be converted by the piezoelectric material, and an additional energy supply module is required to be provided; meanwhile, the complexity and the realization difficulty of the energy management circuit are increased, and the miniaturization and practical design of the energy management circuit and the whole energy acquisition device are facilitated. It is therefore desirable to provide a solution that facilitates a simplified circuit structure while providing self-energizing control of a parallel synchronous switched inductor circuit.

Disclosure of Invention

The invention aims to provide a wireless energy-taking AC/DC converter based on a parallel synchronous switch inductance circuit, which is used for realizing the technical effect of simplifying the circuit structure while carrying out self-energy supply control on the parallel synchronous switch inductance circuit.

The invention provides a wireless energy-taking AC/DC converter based on a parallel synchronous switch inductance circuit, which comprises a piezoelectric material, a forward voltage follower, a reverse voltage follower, a forward switch circuit, a reverse switch circuit, an inductor, a rectifier bridge and a load module, wherein the forward voltage follower is connected with the forward voltage follower; the forward voltage follower, the rectifier bridge and the reverse voltage follower are all connected with the piezoelectric material in parallel; the load module comprises a load and a smoothing capacitor which are connected in parallel; the first end of the load module is connected with the first output end of the rectifier bridge; the second end of the load module is connected with the second output end of the rectifier bridge; the first input end of the forward switch circuit is connected with the forward voltage follower; the second input end and the control end of the forward switch circuit and the first output end and the control end of the reverse switch circuit are both connected with the anode of the piezoelectric material; the second output end of the reverse switch circuit is connected with the reverse voltage follower; the output end of the forward switch circuit and the input end of the reverse switch circuit are both connected with the first end of the inductor; the second end of the inductor is connected with the negative electrode of the piezoelectric material; the forward switching circuit carries out forward switching control on a loop where the inductor is located through the current output by the forward voltage follower and the forward current of the piezoelectric material; and the reverse switch circuit carries out reverse switch control on a loop where the inductor is located through the reverse current of the piezoelectric material.

Further, the forward voltage follower comprises a first resistor, a first diode and a first capacitor; the first end of the first resistor is connected with the positive electrode of the piezoelectric material; the second end of the first resistor is connected with the anode of the first diode; the negative electrode of the first diode is connected with the first end of the first capacitor; and the second end of the first capacitor is connected with the negative electrode of the piezoelectric material.

Further, the forward switch circuit comprises a first triode, a second diode and a third diode; the base electrode of the first triode and the anode of the third diode are both connected with the anode of the piezoelectric material; an emitting electrode of the first triode is connected with a negative electrode of the first diode; the collector of the first triode is connected with the anode of the second diode; the cathode of the second diode is connected with the base electrode of the second triode; the collector of the second triode is connected with the cathode of the third diode; and the emitter of the second triode is connected with the first end of the inductor.

Further, the capacitance value of the first capacitor is 150 pF; the resistance value of the first resistor is 100K omega.

Further, the capacitance value of the flat wave capacitor is 1 uF; the inductance value of the inductor is 10 uH.

Further, the reverse voltage follower comprises a second capacitor, a fourth diode and a second resistor; the first end of the second resistor is connected with the positive electrode of the piezoelectric material; a second end of the second resistor is connected with a cathode of the fourth diode; the anode of the fourth diode is connected with the first end of the second capacitor; and the second end of the second capacitor is connected with the negative electrode of the piezoelectric material.

Further, the reverse switch circuit comprises a third triode, a fourth triode, a fifth diode and a sixth diode; the base electrode of the third triode and the cathode of the six diode are both connected with the anode of the piezoelectric material; an emitting electrode of the third triode is connected with a negative electrode of the fourth diode; a collector of the third triode is connected with a cathode of the fifth diode; the anode of the fifth diode is connected with the base electrode of the fourth triode; a collector of the fourth triode is connected with the anode of the sixth diode; and the emitter of the fourth triode is connected with the first end of the inductor.

Further, the capacitance value of the second capacitor is 150 pF; the resistance value of the second resistor is 100K omega.

The beneficial effects that the invention can realize are as follows: the AC/DC converter provided by the invention is characterized in that the forward voltage follower, the reverse voltage follower, the forward switching circuit, the reverse switching circuit and the rectifier bridge are arranged to form a parallel synchronous switching inductance circuit, and the forward switching circuit and the reverse switching circuit are used for carrying out switching control on a loop where the inductance is located, so that the use of a displacement sensor and a digital control system is avoided, and the circuit structure is greatly simplified while the circuit is subjected to self-function.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

Fig. 1 is a schematic diagram of a wireless energy-taking AC/DC converter based on a parallel synchronous switch inductor circuit according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a voltage following and rectifier bridge conduction process of a parallel synchronous switching inductor circuit according to an embodiment of the present invention;

fig. 3 is a schematic diagram illustrating a first voltage inversion process of a parallel synchronous switched inductor circuit according to an embodiment of the present invention;

fig. 4 is a schematic diagram illustrating a second voltage inversion process of a parallel synchronous switched inductor circuit according to an embodiment of the present invention;

fig. 5 is a schematic diagram illustrating a charge neutralization process of a parallel synchronous switched inductor circuit according to an embodiment of the present invention;

FIG. 6 is a diagram of waveforms of the voltage across the parallel synchronous switched inductor circuit and the current through the rectifier diode according to an embodiment of the present invention;

fig. 7 is an enlarged waveform diagram of a voltage inversion process of the parallel synchronous switch inductor circuit according to an embodiment of the present invention.

Icon: 10-wireless energy-taking AC/DC converter; 100-piezoelectric material; 200-a forward voltage follower; 300-a forward switching circuit; 400-reverse voltage follower; 500-a reverse switching circuit; 600-a rectifier bridge; 700-load module.

Detailed Description

The technical solutions in the embodiments of the present invention will be described below with reference to the drawings in the embodiments of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures. Meanwhile, in the description of the present invention, the terms "first", "second", and the like are used only for distinguishing the description, and are not to be construed as indicating or implying relative importance.

Referring to fig. 1, fig. 1 is a schematic diagram of a wireless energy-taking AC/DC converter based on a parallel synchronous switched inductor circuit according to an embodiment of the present invention.

In one embodiment, the invention provides a wireless energy-taking AC/DC converter 10 based on a parallel synchronous switching inductor circuit, the wireless energy-taking AC/DC converter 10 includes a piezoelectric material 100, a forward voltage follower 200, a reverse voltage follower 400, a forward switching circuit 300, a reverse switching circuit 500, an inductor L, a rectifier bridge 600 and a load module 700; the forward voltage follower 200, the rectifier bridge 600 and the reverse voltage follower 400 are all connected in parallel with the piezoelectric material 100; the load module 700 includes a load and a smoothing capacitor connected in parallel; a first end of the load module 700 is connected to a first output end of the rectifier bridge 600; a second end of the load module 700 is connected to a second output end of the rectifier bridge 600; a first input terminal of the forward switching circuit 300 is connected to the forward voltage follower 200; the second input terminal and the control terminal of the forward switch circuit 300 and the first output terminal and the control terminal of the reverse switch circuit 500 are both connected to the positive electrode of the piezoelectric material 100; a second output terminal of the reverse switching circuit 500 is connected to the reverse voltage follower 400; the output end of the forward switch circuit 300 and the input end of the reverse switch circuit 500 are both connected with the first end of the inductor; the second end of the inductor is connected to the negative electrode of the piezoelectric material 100; the forward switching circuit 300 performs forward switching control on a loop where the inductor is located through the current output by the forward voltage follower 200 and the forward current of the piezoelectric material 100; the reverse switching circuit 500 performs reverse switching control on the loop of the inductor through the reverse current of the piezoelectric material 100.

In the implementation process, the forward voltage follower 200 and the forward switch circuit 300 can perform on-off control and alternating current-direct current conversion when the piezoelectric material 100 provides forward voltage; the reverse voltage follower 400 and the reverse switch circuit 500 can perform on-off control and alternating current-direct current conversion when the piezoelectric material 100 provides a reverse voltage; and a displacement sensor and a digital control system are not needed, so that the circuit structure is simplified while the switch is self-powered.

In one embodiment, the forward voltage follower 200 includes a first resistor R1, a first diode D1, and a first capacitor C1; a first end of the first resistor R1 is connected to the positive electrode of the piezoelectric material 100; a second end of the first resistor R1 is connected to the anode of a first diode D1; the cathode of the first diode D1 is connected with the first end of the first capacitor C1; a second terminal of the first capacitor C1 is connected to the negative terminal of the piezoelectric material 100.

Further, the forward switch circuit 300 includes a first transistor T1, a second transistor T2, a second diode D2, and a third diode D3; the base electrode of the first triode T1 and the anode of the third diode D3 are both connected with the anode of the piezoelectric material 100; the emitter of the first triode is connected with the cathode of a first diode D1; the collector of the first triode T1 is connected with the anode of the second diode D2; the cathode of the second diode D2 is connected with the base of the second triode T2; the collector of the second triode T2 is connected with the cathode of the third diode D3; the emitter of the second transistor T2 is connected to the first terminal of the inductor L.

In the implementation process, the forward voltage follower 200 can change along with the change of the voltage of the piezoelectric material 100; the first transistor T1 and the second diode D2 may form a positive voltage comparator, which is used to compare the voltage of the piezoelectric material 100 with the voltage of the positive voltage follower 200, when the voltage of the positive voltage follower 200 is greater than the voltage of the piezoelectric material 100, it indicates that the voltage of the piezoelectric material 100 has reached a positive amplitude, and at this time, the first transistor T1 may control the conduction of the second transistor T2, and the specific working process is as follows:

the first resistor R1, the first diode D1 and the first capacitor C1 form a forward voltage follower 200, when the forward voltage of the piezoelectric material 100 increases, the first diode D1 is turned on, the first capacitor C1 is charged by the charge through the first resistor R1, and the voltage on the first capacitor C1 follows the voltage change of the piezoelectric material 100; at this time, the second diode D2 is turned off, the voltage between the emitter and the base of the first triode T1 is less than the turn-on voltage, and the first triode T1 is turned off; therefore, the second transistor T2 is also in the off state, i.e., the control switch is in the off state. When the voltage of the piezoelectric material 100 reaches a positive amplitude and starts to decrease, the first diode D1 is subjected to back voltage and is turned off, the voltage of the first capacitor C1 is kept at the positive voltage amplitude of the piezoelectric material 100, and as the voltage of the piezoelectric material 100 continues to decrease, the base potential of the first transistor T1 in the voltage comparator decreases, until the potential difference between the bases of the first capacitor C1 and the second transistor T2 is greater than the sum of the turn-on voltages of the second diode D2 and the first transistor T1, the second diode D2 and the first transistor T1 start to be turned on, so that the third diode D3 and the second transistor T2 are turned on, that is, the forward switch circuit 300 is closed. Then, the first capacitor C1 is discharged through the second diode D2 and the first transistor T1, and when the discharge of the first capacitor C1 is completed, the first transistor T1, the second transistor T2, the second diode D2 and the third diode D3 are all turned off, i.e., the forward switch circuit 300 is turned off. At this time, the first diode D1 is turned on again, the voltage on the first capacitor C1 follows the voltage change of the piezoelectric material 100, and the switch is turned on again after the next positive voltage amplitude of the piezoelectric material 100.

In one embodiment, the reverse voltage follower 400 includes a second capacitor C2, a fourth diode D4, and a second resistor R2; a first end of the second resistor R2 is connected to the positive electrode of the piezoelectric material 100; a second end of the second resistor R2 is connected to the cathode of the fourth diode D4; the anode of the fourth diode D4 is connected to the first end of the second capacitor C2; a second terminal of the second capacitor C2 is connected to the negative pole of the piezoelectric material 100.

In one embodiment, the reverse switching circuit 500 includes a third transistor T3, a fourth transistor T4, a fifth diode D5, and a sixth diode D6; the base electrode of the third triode T3 and the cathode electrode of the sixth diode D6 are both connected with the anode electrode of the piezoelectric material 100; an emitter of the third triode T3 is connected with a cathode of a fourth diode D4; the collector of the third triode T3 is connected with the cathode of the fifth diode D5; the anode of the fifth diode D5 is connected to the base of the fourth transistor T4; an emitter of the fourth triode T4 is connected with a cathode of the second diode D2; the collector of the fourth transistor T4 is connected to the anode of the sixth diode D6.

In the implementation process, the second capacitor C2, the fourth diode D4 and the second resistor R2 form the reverse voltage follower 400, when the reverse voltage of the piezoelectric material 100 gradually increases, the second capacitor C2 starts to charge, when the reverse voltage of the piezoelectric material 100 reaches a peak value and starts to decrease, the voltage of the second capacitor C2 is kept at the peak value, the second capacitor C2 starts to discharge, and the voltage difference between the second capacitor C2 and the positive electrode of the piezoelectric material 100 is large enough, the supplied reverse voltage can make the fourth transistor T4 conduct, so that the sixth diode D6, the fifth diode D5 and the third transistor T3 conduct.

Please refer to fig. 2, fig. 3, fig. 4, fig. 5, fig. 6 and fig. 7; fig. 2 is a schematic diagram of a voltage following and rectifier bridge conduction process of a parallel synchronous switching inductor circuit according to an embodiment of the present invention; fig. 3 is a schematic diagram illustrating a first voltage inversion process of a parallel synchronous switched inductor circuit according to an embodiment of the present invention; fig. 4 is a schematic diagram illustrating a second voltage inversion process of a parallel synchronous switched inductor circuit according to an embodiment of the present invention; fig. 5 is a schematic diagram illustrating a charge neutralization process of a parallel synchronous switched inductor circuit according to an embodiment of the present invention; FIG. 6 is a diagram of waveforms of the voltage across the parallel synchronous switched inductor circuit and the current through the rectifier diode according to an embodiment of the present invention; fig. 7 is an enlarged waveform diagram of a voltage inversion process of the parallel synchronous switch inductor circuit according to an embodiment of the present invention.

In the implementation process, the working process of the circuit can be divided into 4 processes: the method comprises a voltage following and rectifying bridge conduction process, a first voltage inversion process, a second voltage inversion process and a charge neutralization process.

As shown in fig. 2, during the process of conducting the voltage following and rectifying bridge: when the voltage of the piezoelectric material 100 is changed by the forward voltage follower 200 in the forward switch circuit 300, the first diode D1 is turned on, and the first capacitor C1 starts to accumulate charges. For the negative switch, although the fourth diode D4 is turned off by a back voltage, the charging path of the second capacitor C2 through the fourth diode D4 is blocked, a PN junction formed by a base and an emitter of the third transistor T3 is turned on by a positive voltage (but the emitter and the collector are not turned on), and charges are charged to the second capacitor C2 through the PN junction, so that charge accumulation occurs on the second capacitor C2, and the potential also changes along with the voltage change of the piezoelectric material 100; meanwhile, the rectifier bridge 600 also works in a rectification state in the voltage following process; at this time, the piezoelectric material has a voltage V of 100_PHigher than the rectified voltage V_DCThe rectifier bridge 600 turns on the upper arm diode D7 and the lower arm diode D10, and the charge is transferred from the piezoelectric material 100 to the smoothing capacitor Cr through the rectifier bridge 600, but the current at this time is only about 15uA, which is much smaller than the current 600uA of the piezoelectric material 100 during the switch closing period. This means that the charge transfer rate of the piezoelectric material 100 during the switch closing is much higher than when the switch is open, but since the time for the switch closing is very short relative to the mechanical vibration period, the total amount of charge output by the piezoelectric material 100 will be slightly less than that of the switchThe total amount of charge output by the piezoelectric material 100 when the switch is open; piezoelectric material 100V_PAnd a rectified voltage V_DCThe difference in (c) is mainly caused by the conduction voltage drop of the diodes in the rectifier bridge 600.

As shown in FIG. 3, during the first voltage reversal, when the voltage of the piezoelectric material 100 reaches the positive amplitude V₁When the voltage drops, the first diode D1 is under the inverse voltage and is turned off, and the voltage on the first capacitor C1 is kept at V₁-V_D(V_DRepresenting the conduction voltage drop of the third transistor T3). As the voltage of the piezoelectric material 100 gradually decreases to V₁-V_D-V_BE(V_BEIndicating the threshold voltage at which the first transistor T1 is turned on), the voltage between the emitter and the base of the first transistor T1 is higher than the threshold voltage, the first transistor T1 starts to conduct, and the second diode D2, the second transistor T2 and the third diode D3 are all turned on, and the forward switch circuit 300 is closed. At this time, the first capacitor C1 is discharged through the second diode D2, the first triode T1, the second triode T2 and the inductor L, the piezoelectric material 100 forms series resonance with the inductor L through the third diode D3 and the second triode T2, charges accumulated on the piezoelectric material 100 are transferred to the inductor L, and the forward voltage of the piezoelectric material 100 reaches the minimum value V₂。

As shown in fig. 4, during the second voltage inversion, when the charge on the first capacitor C1 is completely discharged, the forward switch circuit 300 is turned off, and the reverse recovery current of the PN junction of the third diode D3 and the second transistor T2 provides a freewheeling path for the inductor L, so that a small amount of charge flows back to the piezoelectric material 100. The voltage of the piezoelectric material 100 is changed from V₂Slightly rising to V₃Although this voltage rise is of very small magnitude, the presence of a local minimum may cause the negative switch to malfunction. To avoid this, the discharge process of the second capacitor C2 needs to be limited by the second resistor R2, so that the discharge speed of the second capacitor C2 is slower than that of the piezoelectric material 100.

As shown in fig. 5, during charge neutralization, the charge on the second capacitor C2 is transferred to the first capacitor C1 and the piezoelectric material 100 through the fourth diode D4. This process starts with a piezoelectric material 100The voltage is already present when the voltage starts to drop from the positive amplitude value, namely the voltage is simultaneously present with the first voltage inversion process and the second voltage inversion process; this results in a certain charge backflow phenomenon in the series switched synchronous charge extraction circuit. Although the second capacitor C2 is also provided with a discharge path via the fourth diode D4 and the rectifier bridge 600 in the parallel synchronous switched inductor circuit, the highest voltage V on the second capacitor C2 is generated₁-V_D-V_BEAnd a rectified voltage V_DCAnd the voltage drops during discharging, the second capacitor C2 cannot transfer the charge to the smoothing capacitor Cr through the rectifier bridge 600. The circuit then waits for the arrival of a negative amplitude of the voltage of the piezoelectric material 100.

It should be noted that, in order to reduce the influence of the charge neutralization process, the second capacitor C2 should be as small as possible to reduce the charge and energy of the backflow and improve the conversion efficiency. However, if the second capacitor C2 is too small, the charge on the second capacitor C2 will not reliably turn on the third transistor T3, and the negative-going switching current will not reliably turn on, so it should be noted that the first capacitor C1 and the second capacitor C2 are selected.

In one embodiment, the capacitance value of the first capacitor C1 is 150 pF; the resistance value of the first resistor R1 is 100K omega; the capacitance value of the second capacitor C2 is 150 pF; the resistance value of the second resistor R2 is 100K omega; the capacitance value of the flat wave capacitor is 1 uF; the inductance value of the inductor is 10 uH; in this way, the influence of the charge neutralization process can be weakened, the charge and energy of the backflow can be reduced, and the conversion efficiency can be improved.

In summary, the embodiment of the present invention provides a wireless energy-taking AC/DC converter based on a series synchronous switch inductor circuit, which includes a piezoelectric material, a forward voltage follower, a reverse voltage follower, a forward switch circuit, a reverse switch circuit, an inductor, a rectifier bridge, and a load module; the forward voltage follower, the rectifier bridge and the reverse voltage follower are connected with the piezoelectric material in parallel; the load module comprises a load and a smoothing capacitor which are connected in parallel; the first end of the load module is connected with the first output end of the rectifier bridge; the second end of the load module is connected with the second output end of the rectifier bridge; the first input end of the forward switch circuit is connected with the forward voltage follower; the second input end and the control end of the forward switch circuit and the first output end and the control end of the reverse switch circuit are both connected with the positive electrode of the piezoelectric material; the second output end of the reverse switch circuit is connected with the reverse voltage follower; the output end of the forward switch circuit and the input end of the reverse switch circuit are both connected with the first end of the inductor; the second end of the inductor is connected with the negative electrode of the piezoelectric material; the forward switching circuit carries out forward switching control on a loop where the inductor is located through the current output by the forward voltage follower and the forward current of the piezoelectric material; the reverse switch circuit carries out reverse switch control on a loop where the inductor is located through reverse current of the piezoelectric material. Through the process, the use of a displacement sensor and a digital control system is avoided, and the circuit structure is greatly simplified while the circuit is subjected to self-function.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.