Wireless charging circuit, charging seat and induction charging system

Abstract

The utility model discloses a wireless charging circuit, a charging seat and an induction charging system, and relates to the technical field of wireless charging. The charging seat comprises an alternating current input end, the wireless charging circuit comprises a protection circuit, and a first end of the protection circuit is electrically connected with the alternating current input end; the protection circuit is used for respectively limiting the input voltage and the input current of the alternating current input end within a preset voltage range and a preset current range and outputting the input voltage and the input current; the first end of the rectification circuit is electrically connected with the second end of the protection circuit; the rectifying circuit is used for converting the alternating current output by the protection circuit into direct current and outputting the direct current; the input end of the double-circle mutual inductance resonance circuit is electrically connected with the second end of the rectifying circuit; and the double-circle mutual inductance resonance circuit is used for generating a corresponding changing magnetic field when receiving the changing direct current. The utility model aims to improve the wireless charging efficiency and stability of the equipment to be charged.

Description

Technical Field

[0001] This utility model relates to the field of wireless charging technology, and in particular to a wireless charging circuit, a charging base, and an inductive charging system. Background Technology

[0002] In current technology, most electric toothbrushes are charged via wired charging. However, wired charging requires a specific connection interface, and electric toothbrushes are frequently in contact with liquids. Therefore, using wired charging in electric toothbrushes can easily cause circuit damage. Furthermore, existing wireless charging methods for electric toothbrushes suffer from unstable charging and low charging efficiency. Utility Model Content

[0003] The main purpose of this invention is to provide a wireless charging circuit, a charging base, and an inductive charging system, which aims to improve the wireless charging efficiency and stability of the device to be charged.

[0004] To achieve the above objectives, the present invention proposes a wireless charging circuit for use in a charging dock, the charging dock including an AC input terminal, and the wireless charging circuit including:

[0005] A protection circuit, wherein the first terminal of the protection circuit is electrically connected to the AC input terminal; the protection circuit is used to limit the input voltage and input current of the AC input terminal to preset voltage and preset current ranges respectively and output them.

[0006] A rectifier circuit, wherein a first terminal of the rectifier circuit is electrically connected to a second terminal of the protection circuit; the rectifier circuit is used to convert the AC power output by the protection circuit into DC power and output it.

[0007] A double-turn mutual inductance resonant circuit, wherein the input terminal of the double-turn mutual inductance resonant circuit is electrically connected to the second terminal of the rectifier circuit; the double-turn mutual inductance resonant circuit is used to generate a corresponding changing magnetic field when receiving a changing direct current.

[0008] In one embodiment, the protection circuit includes a first resistor, a fuse, a thermistor, and an adjustable resistor;

[0009] Wherein, the first end of the first resistor is electrically connected to the first end of the AC input terminal, and the second end of the first resistor is electrically connected to the first end of the fuse; the second end of the fuse is electrically connected to the first end of the adjustable resistor and the first end of the rectifier circuit; the second end of the adjustable resistor is electrically connected to the input terminal of the rectifier circuit and the second end of the thermistor; and the first end of the thermistor is electrically connected to the second end of the AC input terminal.

[0010] In one embodiment, the rectifier circuit includes:

[0011] A half-wave rectifier circuit, wherein the first terminal of the half-wave rectifier circuit is electrically connected to the second terminal of the protection circuit; the half-wave rectifier circuit is used to convert the input AC power into the corresponding DC power and output it.

[0012] A filter circuit is provided, wherein the input terminal of the filter circuit is electrically connected to the output terminal of the half-wave rectifier circuit, and the output terminal of the filter circuit is electrically connected to the input terminal of the double-coil mutual inductance resonant circuit; the filter circuit is used to filter the input DC power before outputting it.

[0013] In one embodiment, the half-wave rectifier circuit includes a first diode and a second diode; the filter circuit includes a first capacitor;

[0014] The anode of the first diode is electrically connected to the protection circuit, and the cathode of the first diode is electrically connected to the double-turn mutual inductance resonant circuit and the first terminal of the first capacitor; the anode of the second diode is electrically connected to the double-turn mutual inductance resonant circuit and the second terminal of the first capacitor, and the cathode of the second diode is electrically connected to the protection circuit.

[0015] In one embodiment, the double-turn mutual inductance resonant circuit includes:

[0016] A first mutual inductance resonant circuit, wherein the input terminal of the first mutual inductance resonant circuit is electrically connected to the output terminal of the rectifier circuit; the first mutual inductance resonant circuit is used to generate a corresponding changing magnetic field when receiving a changing direct current.

[0017] The second mutual inductance resonant circuit has its input terminal electrically connected to the first mutual inductance resonant circuit. The second mutual inductance resonant circuit is used to generate a corresponding changing magnetic field when it receives a corresponding changing magnetic field generated by the first mutual inductance resonant circuit.

[0018] In one embodiment, the first mutual inductance resonant circuit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first Zener diode, a third diode, a first switching transistor, and a first inductor.

[0019] Wherein, the first end of the second resistor is electrically connected to the rectifier circuit, the first end of the second capacitor, the first end of the first inductor, and the first end of the fourth capacitor; the second end of the second resistor is electrically connected to the first end of the third resistor; the second end of the third resistor is electrically connected to the second end of the second capacitor, the controlled end of the first switch, the first end of the fourth resistor, and the second mutual inductance resonant circuit; the second end of the fourth resistor is electrically connected to the rectifier circuit, the anode of the first Zener diode, the sixth resistor, the second mutual inductance resonant circuit, and the ground terminal; the second end of the first inductor is electrically connected to the first end of the first switch and the first end of the fifth resistor; the second end of the fifth resistor is electrically connected to the first end of the third capacitor; the second end of the third capacitor is electrically connected to the second end of the fourth capacitor, the cathode of the third diode, the first end of the sixth resistor, and the cathode of the first Zener diode; the second end of the first switch is electrically connected to the anode of the third diode.

[0020] In one embodiment, the second mutual inductance resonant circuit includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fifth capacitor, a sixth capacitor, a seventh capacitor, a fourth diode, a fifth diode, a second Zener diode, a third Zener diode, a second switching transistor, and a second inductor.

[0021] Specifically, the first terminal of the seventh resistor is electrically connected to the first terminal of the eighth resistor, the first terminal of the eleventh resistor, and the first mutual inductance resonant circuit; the second terminal of the seventh resistor is electrically connected to the first terminal of the second switch, the second terminal of the eighth resistor, and the first terminal of the fifth capacitor; the second terminal of the fifth capacitor is electrically connected to the first terminal of the ninth resistor; the second terminal of the ninth resistor is electrically connected to the controlled terminal of the second switch, the first terminal of the tenth resistor, and the anode of the third Zener diode; the cathode of the third Zener diode is electrically connected to the anode of the second Zener diode; and the cathode of the second Zener diode is electrically connected to the sixth resistor. The first terminal of the capacitor and the second terminal of the thirteenth resistor are electrically connected; the second terminal of the first switching transistor is electrically connected to the first mutual inductance resonant circuit, the second terminal of the tenth resistor, the second terminal of the sixth capacitor, the second terminal of the second inductor coil, and the second terminal of the seventh capacitor; the second terminal of the eleventh resistor is electrically connected to the first terminal of the twelfth resistor and the first terminal of the seventh capacitor; the second terminal of the twelfth resistor is electrically connected to the cathode of the fourth diode; the anode of the fourth diode is electrically connected to the anode of the fifth diode and the first terminal of the second inductor coil; the first terminal of the thirteenth resistor is electrically connected to the cathode of the fifth diode.

[0022] This utility model also proposes a charging dock, which includes an AC input terminal and a wireless charging circuit as described in any of the above claims.

[0023] This utility model also proposes an inductive charging system, which includes a device to be charged and a charging dock as described above.

[0024] This utility model provides a wireless charging circuit to improve the efficiency and stability of wireless charging for devices. The wireless charging circuit includes a protection circuit, a rectifier circuit, and a dual-coil resonant circuit. The protection circuit's input terminal is connected to the AC input terminal, limiting the voltage and current input to preset voltage and current ranges before outputting to the rectifier circuit. The rectifier circuit rectifies the input AC voltage, converting it into DC power, which is then output to the dual-coil resonant circuit. The dual-coil resonant circuit generates a magnetic field through the DC power output from the rectifier circuit. Another coil is located inside the device being charged; when it approaches the transmitting coil, it generates a current within itself due to mutual inductance, thus charging the device. To improve efficiency and allow for a certain distance or positional deviation, the two coils are tuned to the same resonant frequency, ensuring effective energy transfer even if there is a distance between them or they are not perfectly aligned. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the wireless charging circuit of this utility model.

[0027] Figure 2 This is a schematic diagram of a module of an embodiment of the wireless charging circuit of this utility model;

[0028] Figure 3 This is a circuit diagram of the wireless charging circuit of this utility model.

[0029] Explanation of icon numbers:

[0030] 10. Protection circuit; 20. Rectifier circuit; 21. Half-wave rectifier circuit; 22. Filter circuit; 30. Double-circuit mutual inductance resonant circuit; 31. First mutual inductance resonant circuit; 32. Second mutual inductance resonant circuit; R1-R13, First resistor-Thirteenth resistor; C1-C7, First capacitor-Seventh capacitor; D1-D2, First diode-Second diode; D3, First Zener diode; D4, Third diode; D5-D6, Second Zener diode-Third Zener diode; D7-D8, Fourth diode-Fifth diode; Q1-Q2, First switching transistor-Second switching transistor; F, Fuse; RV, Adjustable resistor; RT, Thermistor.

[0031] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0033] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0034] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0035] In current technology, most electric toothbrushes are charged via wired charging. However, wired charging requires a specific connection interface, and electric toothbrushes are frequently in contact with liquids. Therefore, using wired charging in electric toothbrushes can easily cause circuit damage. Furthermore, existing wireless charging methods for electric toothbrushes suffer from unstable charging and low charging efficiency.

[0036] Therefore, refer to Figures 1 to 3 This utility model proposes a wireless charging circuit for use in a charging dock, the charging dock including an AC input terminal, and the wireless charging circuit including:

[0037] Protection circuit 10, the first terminal of which is electrically connected to the AC input terminal; the protection circuit 10 is used to limit the input voltage and input current of the AC input terminal to preset voltage and preset current ranges respectively and output them.

[0038] A rectifier circuit 20, the first terminal of which is electrically connected to the second terminal of the protection circuit 10; the rectifier circuit 20 is used to convert the AC power output by the protection circuit 10 into DC power and output it.

[0039] A double-loop mutual inductance resonant circuit 30 is provided, the input terminal of which is electrically connected to the second terminal of the rectifier circuit 20. The double-loop mutual inductance resonant circuit 30 is used to generate a corresponding changing magnetic field when it receives a changing direct current.

[0040] In this embodiment, the protection circuit 10 can be implemented using a voltage regulator circuit, a current limiting circuit, etc. The voltage regulator circuit can be implemented using a Zener diode and its corresponding circuit; the current limiting circuit can be implemented using a fuse F. Optionally, the protection circuit 10 includes a first resistor R1, a fuse F, a thermistor RT, and an adjustable resistor RV; wherein, the first end of the first resistor R1 is electrically connected to the first end of the AC input terminal, and the second end of the first resistor R1 is electrically connected to the first end of the fuse F; the second end of the fuse F is electrically connected to the first end of the adjustable resistor RV and the first end of the rectifier circuit 20; the second end of the adjustable resistor RV is electrically connected to the input terminal of the rectifier circuit 20 and the second end of the thermistor RT; the first end of the thermistor RT is electrically connected to the second end of the AC input terminal. The first resistor R1 is a current limiting resistor to prevent excessive current from damaging other electronic components. By connecting an appropriate current limiting resistor in series, the current flowing through subsequent circuits can be controlled, ensuring that they operate within a safe range. Current-limiting resistors also help reduce electromagnetic interference because they can reduce rapidly changing current peaks in a circuit, thereby reducing radiated electromagnetic waves. Fuse F is used to prevent damage to the circuit due to excessive current. When the current in the circuit exceeds the rated value of fuse F, fuse F will melt due to its own heat, thus cutting off the circuit and preventing excessive current from continuing to flow through other components in the circuit. This effectively prevents damage to circuits and equipment caused by current surges due to electrical equipment failure, short circuits, or power supply problems. By preventing the current from exceeding the maximum rated value of the equipment, fuse F helps protect the equipment from potential permanent damage, thus extending its service life. Thermistors RT can be NTC or PTC resistors. The resistance of an NTC resistor decreases as temperature increases. This means that when the ambient temperature or the current flowing through the resistor increases, causing its temperature to rise, the resistance of an NTC resistor will decrease. In contrast, the resistance of a PTC resistor increases as temperature increases. Once a certain temperature point is exceeded, the resistance rises sharply, giving PTC resistors a self-limiting temperature characteristic. The wireless charging circuit can receive the temperature detection signal by setting a corresponding control circuit and adjust the resistance value of the adjustable resistor RV to avoid the wireless charging circuit from overheating.

[0041] In this embodiment, the rectifier circuit 20 can be implemented using a bridge rectifier circuit 20 and a half-wave rectifier circuit 21. Optionally, the rectifier circuit 20 includes: a half-wave rectifier circuit 21, the first terminal of which is electrically connected to the second terminal of the protection circuit 10; the half-wave rectifier circuit 21 is used to convert the input AC power into the corresponding DC power and output it; and a filter circuit 22, the input terminal of which is electrically connected to the output terminal of the half-wave rectifier circuit 21, and the output terminal of which is electrically connected to the input terminal of the double-coil mutual inductance resonant circuit 30; the filter circuit 22 is used to filter the input DC power before outputting it. The half-wave rectifier circuit 21 includes a first diode D1 and a second diode D2; the filter circuit 22 includes a first capacitor C1; wherein, the anode of the first diode D1 is electrically connected to the protection circuit 10, and the cathode of the first diode D1 is electrically connected to the double-turn mutual inductance resonant circuit 30 and the first terminal of the first capacitor C1; the anode of the second diode D2 is electrically connected to the double-turn mutual inductance resonant circuit 30 and the second terminal of the first capacitor C1, and the cathode of the second diode D2 is electrically connected to the protection circuit 10. It can be understood that the half-wave rectifier circuit 21 receives a sinusoidal AC input. This input voltage changes its direction and magnitude periodically with time. In the half-wave rectifier circuit 21, the first diode D1 and the second diode D2 are used as rectifier elements. Diodes have unidirectional conductivity, meaning they only allow current to flow from their anode to their cathode, while preventing current from flowing in the opposite direction. When the input AC voltage is in the positive half-cycle, the diode is forward biased. At this time, the diode conducts, allowing current to flow, and a voltage with the same waveform as the input voltage but in the same direction is obtained on the load. When the input AC voltage enters the negative half-cycle, the diode is reverse biased. At this time, the diode is cut off, preventing current from flowing, so no current flows to the load, and the voltage across the load drops to zero or remains in the previous state. Furthermore, after the rectifier circuit 20 converts the AC power into pulsating DC power, the output voltage contains a significant ripple component. These ripples can be reduced by using the filter circuit 22, making the output closer to ideal DC power.

[0042] In this embodiment, the dual-loop mutual inductance resonant circuit 30 includes a first mutual inductance resonant circuit 31, the input terminal of which is electrically connected to the output terminal of the rectifier circuit 20; the first mutual inductance resonant circuit 31 is used to generate a corresponding changing magnetic field when receiving a changing direct current; and a second mutual inductance resonant circuit 32, the input terminal of which is electrically connected to the first mutual inductance resonant circuit 31; the second mutual inductance resonant circuit 32 is used to generate a corresponding changing magnetic field when receiving a corresponding changing magnetic field generated by the first mutual inductance resonant circuit 31. Specifically, the first mutual inductance resonant circuit 31 includes a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first capacitor C1, a second capacitor C2, a third capacitor C3, a fourth capacitor C4, a first Zener diode D3, a third diode D4, a first switching transistor Q1, and a first inductor. The first terminal of the second resistor R2 is electrically connected to the rectifier circuit 20, the first terminal of the second capacitor C2, the first terminal of the first inductor, and the first terminal of the fourth capacitor C4. The second terminal of the second resistor R2 is electrically connected to the first terminal of the third resistor R3. The second terminal of the third resistor R3 is connected to the second terminal of the second capacitor C2, the controlled terminal of the first switching transistor Q1, and the fourth resistor R6. The first terminal of resistor R4 is electrically connected to the second mutual inductance resonant circuit 32; the second terminal of the fourth resistor R4 is electrically connected to the rectifier circuit 20, the anode of the first Zener diode D3, the sixth resistor R6, the second mutual inductance resonant circuit 32, and the ground terminal; the second terminal of the first inductor is electrically connected to the first terminal of the first switch Q1 and the first terminal of the fifth resistor R5; the second terminal of the fifth resistor R5 is electrically connected to the first terminal of the third capacitor C3; the second terminal of the third capacitor C3 is electrically connected to the second terminal of the fourth capacitor C4, the cathode of the third diode D4, the first terminal of the sixth resistor R6, and the cathode of the first Zener diode D3; the second terminal of the first switch Q1 is electrically connected to the anode of the third diode D4.The second mutual inductance resonant circuit 32 includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, a tenth resistor R10, an eleventh resistor R11, a twelfth resistor R12, a thirteenth resistor R13, a fifth capacitor C5, a sixth capacitor C6, a seventh capacitor C7, a fourth diode D7, a fifth diode D8, a second Zener diode D5, a third Zener diode D6, a second switch Q2, and a second inductor coil; wherein, the first terminal of the seventh resistor R7 is electrically connected to the first terminal of the eighth resistor R8, the first terminal of the eleventh resistor R11, and the first mutual inductance resonant circuit 31; the second terminal of the seventh resistor R7 is electrically connected to the first terminal of the second switch Q2, the second terminal of the eighth resistor R8, and the first terminal of the fifth capacitor C5; the second terminal of the fifth capacitor C5 is electrically connected to the first terminal of the ninth resistor R9; the second terminal of the ninth resistor R9 is electrically connected to the controlled terminal of the second switch Q2, the first terminal of the tenth resistor R10, and the second inductor coil. The anode of the third Zener diode D6 is electrically connected; the cathode of the third Zener diode D6 is electrically connected to the anode of the second Zener diode D5; the cathode of the second Zener diode D5 is electrically connected to the first terminal of the sixth capacitor C6 and the second terminal of the thirteenth resistor R13; the second terminal of the first switch Q1 is electrically connected to the first mutual inductance resonant circuit 31, the second terminal of the tenth resistor R10, the second terminal of the sixth capacitor C6, the second terminal of the second inductor, and the second terminal of the seventh capacitor C7; the second terminal of the eleventh resistor R11 is electrically connected to the first terminal of the twelfth resistor R12 and the first terminal of the seventh capacitor C7; the second terminal of the twelfth resistor R12 is electrically connected to the cathode of the fourth diode D7; the anode of the fourth diode D7 is electrically connected to the anode of the fifth diode D8 and the first terminal of the second inductor; the first terminal of the thirteenth resistor R13 is electrically connected to the cathode of the fifth diode D8. Wireless charging typically utilizes electromagnetic induction or magnetic resonance principles to transfer energy. In a wireless charging system based on a dual-loop mutual inductance resonant circuit 30, a first inductor coil is connected to a power source and generates a magnetic field through current. A second inductor coil, by being close to the first inductor coil, generates current within itself due to mutual inductance. When the receiving coil is located inside the device to be charged and close to the wireless charging circuit, it generates current within itself due to mutual inductance, thereby charging the device. The use of both the first and second inductor coils effectively improves the charging efficiency of the device.

[0043] A wireless charging circuit is employed to improve the efficiency and stability of wireless charging for the device being charged. This circuit includes a protection circuit 10, a rectifier circuit 20, and a dual-coil resonant circuit. The protection circuit 10 has an input terminal connected to an AC input terminal, limiting the voltage and current input to preset voltage and current ranges before outputting to the rectifier circuit 20. The rectifier circuit 20 rectifies the input AC voltage, converting it into DC power, which is then output to the dual-coil resonant circuit 30. The dual-coil resonant circuit generates a magnetic field through the DC power output from the rectifier circuit 20. Another coil is located inside the device being charged; when it approaches the transmitting coil, it generates a current within itself due to mutual inductance, thus charging the device. To improve efficiency and allow for a certain distance or positional deviation, the two coils are tuned to the same resonant frequency, ensuring effective energy transfer even if there is a distance between them or they are not perfectly aligned.

[0044] This utility model also proposes a charging dock, which includes an AC input terminal and a wireless charging circuit as described in any of the above claims. It is worth noting that since this utility model's charging dock is based on the aforementioned wireless charging circuit, the embodiments of this utility model's charging dock include all the technical solutions of all the embodiments of the aforementioned wireless charging circuit, and the achieved technical effects are completely the same, and will not be repeated here.

[0045] This utility model also proposes an inductive charging system, which includes a device to be charged and a charging dock as described above. It is worth noting that since this utility model's inductive charging system is based on the aforementioned charging dock, the embodiments of this utility model's inductive charging system include all the technical solutions of all the embodiments of the aforementioned charging dock, and the achieved technical effects are completely the same, and will not be repeated here.

[0046] The above description is merely an exemplary embodiment of the present utility model and does not limit the patent scope of the present utility model. Any equivalent structural transformations made based on the technical concept of the present utility model and the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A wireless charging circuit, applied to a charging dock, characterized in that, The charging dock includes an AC input terminal, and the wireless charging circuit includes: A protection circuit, wherein the first terminal of the protection circuit is electrically connected to the AC input terminal; the protection circuit is used to limit the input voltage and input current of the AC input terminal to preset voltage and preset current ranges respectively and output them. A rectifier circuit, wherein a first terminal of the rectifier circuit is electrically connected to a second terminal of the protection circuit; the rectifier circuit is used to convert the AC power output by the protection circuit into DC power and output it. A double-turn mutual inductance resonant circuit, wherein the input terminal of the double-turn mutual inductance resonant circuit is electrically connected to the second terminal of the rectifier circuit; the double-turn mutual inductance resonant circuit is used to generate a corresponding changing magnetic field when receiving a changing direct current.

2. The wireless charging circuit as described in claim 1, characterized in that, The protection circuit includes a first resistor, a fuse, a thermistor, and an adjustable resistor; Wherein, the first end of the first resistor is electrically connected to the first end of the AC input terminal, and the second end of the first resistor is electrically connected to the first end of the fuse; the second end of the fuse is electrically connected to the first end of the adjustable resistor and the first end of the rectifier circuit; the second end of the adjustable resistor is electrically connected to the input terminal of the rectifier circuit and the second end of the thermistor; and the first end of the thermistor is electrically connected to the second end of the AC input terminal.

3. The wireless charging circuit as described in claim 1, characterized in that, The rectifier circuit includes: A half-wave rectifier circuit, wherein the first terminal of the half-wave rectifier circuit is electrically connected to the second terminal of the protection circuit; the half-wave rectifier circuit is used to convert the input AC power into the corresponding DC power and output it. A filter circuit is provided, wherein the input terminal of the filter circuit is electrically connected to the output terminal of the half-wave rectifier circuit, and the output terminal of the filter circuit is electrically connected to the input terminal of the double-coil mutual inductance resonant circuit; the filter circuit is used to filter the input DC power before outputting it.

4. The wireless charging circuit as described in claim 3, characterized in that, The half-wave rectifier circuit includes a first diode and a second diode; the filter circuit includes a first capacitor. The anode of the first diode is electrically connected to the protection circuit, and the cathode of the first diode is electrically connected to the double-turn mutual inductance resonant circuit and the first terminal of the first capacitor; the anode of the second diode is electrically connected to the double-turn mutual inductance resonant circuit and the second terminal of the first capacitor, and the cathode of the second diode is electrically connected to the protection circuit.

5. The wireless charging circuit as described in claim 1, characterized in that, The double-loop mutual inductance resonant circuit includes: A first mutual inductance resonant circuit, wherein the input terminal of the first mutual inductance resonant circuit is electrically connected to the output terminal of the rectifier circuit; the first mutual inductance resonant circuit is used to generate a corresponding changing magnetic field when receiving a changing direct current. The second mutual inductance resonant circuit has its input terminal electrically connected to the first mutual inductance resonant circuit. The second mutual inductance resonant circuit is used to generate a corresponding changing magnetic field when it receives a corresponding changing magnetic field generated by the first mutual inductance resonant circuit.

6. The wireless charging circuit as described in claim 5, characterized in that, The first mutual inductance resonant circuit includes a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a first capacitor, a second capacitor, a third capacitor, a fourth capacitor, a first Zener diode, a third diode, a first switching transistor, and a first inductor coil; Wherein, the first end of the second resistor is electrically connected to the rectifier circuit, the first end of the second capacitor, the first end of the first inductor, and the first end of the fourth capacitor; the second end of the second resistor is electrically connected to the first end of the third resistor; the second end of the third resistor is electrically connected to the second end of the second capacitor, the controlled end of the first switch, the first end of the fourth resistor, and the second mutual inductance resonant circuit; the second end of the fourth resistor is electrically connected to the rectifier circuit, the anode of the first Zener diode, the sixth resistor, the second mutual inductance resonant circuit, and the ground terminal; the second end of the first inductor is electrically connected to the first end of the first switch and the first end of the fifth resistor; the second end of the fifth resistor is electrically connected to the first end of the third capacitor; the second end of the third capacitor is electrically connected to the second end of the fourth capacitor, the cathode of the third diode, the first end of the sixth resistor, and the cathode of the first Zener diode; the second end of the first switch is electrically connected to the anode of the third diode.

7. The wireless charging circuit as described in claim 5, characterized in that, The second mutual inductance resonant circuit includes a seventh resistor, an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fifth capacitor, a sixth capacitor, a seventh capacitor, a fourth diode, a fifth diode, a second Zener diode, a third Zener diode, a second switching transistor, and a second inductor. Specifically, the first terminal of the seventh resistor is electrically connected to the first terminal of the eighth resistor, the first terminal of the eleventh resistor, and the first mutual inductance resonant circuit; the second terminal of the seventh resistor is electrically connected to the first terminal of the second switch, the second terminal of the eighth resistor, and the first terminal of the fifth capacitor; the second terminal of the fifth capacitor is electrically connected to the first terminal of the ninth resistor; the second terminal of the ninth resistor is electrically connected to the controlled terminal of the second switch, the first terminal of the tenth resistor, and the anode of the third Zener diode; the cathode of the third Zener diode is electrically connected to the anode of the second Zener diode; and the cathode of the second Zener diode is electrically connected to the sixth resistor. The first terminal of the capacitor and the second terminal of the thirteenth resistor are electrically connected; the second terminal of the first switching transistor is electrically connected to the first mutual inductance resonant circuit, the second terminal of the tenth resistor, the second terminal of the sixth capacitor, the second terminal of the second inductor coil, and the second terminal of the seventh capacitor; the second terminal of the eleventh resistor is electrically connected to the first terminal of the twelfth resistor and the first terminal of the seventh capacitor; the second terminal of the twelfth resistor is electrically connected to the cathode of the fourth diode; the anode of the fourth diode is electrically connected to the anode of the fifth diode and the first terminal of the second inductor coil; the first terminal of the thirteenth resistor is electrically connected to the cathode of the fifth diode.

8. A charging stand, characterized in that, The charging dock includes an AC input terminal and a wireless charging circuit as described in any one of claims 1 to 7.

9. An inductive charging system, characterized in that, The inductive charging system includes a device to be charged and a charging dock as described in claim 8.

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