ZVS magnetic coupling resonant wireless charging electronic acne paste

Abstract

The invention provides a ZVS magnetic coupling resonant wireless charging electronic acne patch which comprises a transmitting end and a receiving end, the transmitting end is provided with a ZVS circuit, and the receiving end is provided with a magnetic coupling resonant circuit; the ZVS circuit carries out zero-voltage switching on based on an input voltage signal, the ZVS circuit is matched with the LC resonant frequency of the magnetic coupling resonant circuit through LC resonance based on a switching-on signal, a switched-on electric signal is coupled to a receiving end, and the receiving end carries out corresponding control based on a received signal; by introducing the zero-voltage switch, the switching loss is reduced, and the system efficiency is improved; meanwhile, through the magnetic coupling resonance principle, the distance of wireless energy transmission is prolonged, the stability of energy transmission is enhanced, and the device adapts to the use scene of the acne paste.

Description

Technical Field

[0001] The present invention relates to the field of wireless charging technology, and in particular to a ZVS magnetic coupling resonance type wireless charging circuit for an electronic acne patch. Background Art

[0002] Due to space limitations, existing electronic acne patches generally do not have wireless charging functions. The application of wireless charging technology in existing electronic acne patch products is limited by space and design, and common problems include low charging efficiency and severe device heating. These problems usually lead to poor user experience and limit the portability and service life of the product.

[0003] Existing technologies have deficiencies in circuit design and energy transmission efficiency. Conventional wireless charging circuits are usually unable to achieve efficient energy transmission in small devices, and are prone to generating excessive heat during the charging process, affecting the safety and comfort of the device. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the present invention provides a ZVS magnetic coupling resonance type wireless charging electronic acne patch, which is suitable for electronic acne patches, reduces space occupation, and optimizes charging efficiency. By introducing ZVS technology to improve charging efficiency, energy loss and equipment heating are reduced, while reducing power supply costs and improving efficiency. Utilizing magnetic coupling resonance technology, the stability and efficiency of wireless energy transmission are enhanced to meet the special needs of electronic acne patches.

[0005] In order to achieve the above object, the present invention provides a ZVS magnetic coupling resonance type wireless charging electronic acne patch, which comprises: The transmitting end and the receiving end are provided with a ZVS circuit at the transmitting end and a magnetic coupling resonance circuit at the receiving end; the ZVS circuit performs zero voltage switching based on the input voltage signal, and based on the switching signal, the ZVS circuit matches the LC resonance frequency of the magnetic coupling resonance circuit through LC resonance, and couples the switched-on electrical signal to the receiving end, and the receiving end performs corresponding control based on the received signal.

[0006] Preferably, the ZVS circuit includes: resonant inductors L2 and L3 connected at one end; a choke coil L1 having one end connected to the input ends of the resonant inductors L2 and L3 and the other end connected to a power supply; a resonant capacitor C2 connected to the output ends of the resonant inductors L2 and L3 respectively; a MOS transistor Q1 and a MOS transistor Q2, wherein the gates of the MOS transistors Q1 and Q2 are connected together to the output end of the resonant inductor L3, the drain is connected to the output end of the resonant inductor L2, and the source is grounded; and a resonant capacitor C1, having one end connected to the power supply and the other end grounded.

[0007] Preferably, the resonant inductor L2 and the resonant inductor L3 constitute a carrier coil T1, a coil is provided in the receiving end, and the turn-on signal is coupled to the coil of the receiving end through the carrier coil T1.

[0008] Preferably, the resonant inductor L2 and the resonant inductor L3 are manufactured by circuit routing on a circuit board.

[0009] Preferably, the plate coil T1 and the coil at the receiving end are charged by using the coil centers and routing lines to face each other with the largest area.

[0010] Preferably, the LC resonance frequency in the ZVS circuit is the same as the LC resonance frequency in the magnetic coupling resonance circuit. Beneficial Effects

[0011] 1. Improve the wireless charging efficiency and stability of electronic acne patches.

[0012] 2. Reduce energy loss and heat during charging, and improve device safety and user experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A structural diagram of a wireless charging system of a ZVS magnetically coupled resonant wireless charging electronic acne patch provided by the present invention; Figure 2 A ZVS optimization circuit for a ZVS magnetically coupled resonant wireless charging electronic acne patch provided by the present invention; Figure 3 A coupled resonance structure diagram of a ZVS magnetically coupled resonance type wireless charging electronic acne patch provided by the present invention; Figure 4 A schematic diagram of charging of a carrier coil at the transmitting end and a coil at the receiving end in a ZVS magnetic coupling resonance type wireless charging electronic acne patch provided by the present invention; Figure 5 This is a system workflow diagram of a ZVS magnetically coupled resonant wireless charging electronic acne patch provided by the present invention. DETAILED DESCRIPTION

[0014] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0015] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0016] All directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, horizontal, vertical...) are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0017] Due to installation errors and other reasons, the parallel relationship referred to in the embodiments of the present invention may actually be an approximately parallel relationship, and the vertical relationship may actually be an approximately vertical relationship.

[0018] like Figure 1 As shown, a ZVS magnetic coupling resonance type wireless charging electronic acne patch comprises: The transmitting end and the receiving end are provided with a ZVS circuit at the transmitting end and a magnetic coupling resonance circuit at the receiving end; the ZVS circuit performs zero voltage switching based on the input voltage signal, and based on the switching signal, the ZVS circuit matches the LC resonance frequency of the magnetic coupling resonance circuit through LC resonance, and couples the switched-on electrical signal to the receiving end, and the receiving end performs corresponding control based on the received signal.

[0019] Specifically, the present invention realizes zero voltage switching through a ZVS circuit, reduces switching losses, improves system efficiency, and also reduces power supply and unnecessary components, thereby optimizing efficiency. Among them, the magnetic coupling resonant circuit adopts the magnetic coupling resonance principle, maximizes energy transfer by matching the resonant frequencies of the transmitting and receiving coils, and improves energy transfer efficiency.

[0020] like Figure 2 As shown, the ZVS circuit provided by the present invention includes: resonant inductors L2 and L3 connected at one end; a choke coil L1 connected to the input end of the resonant inductors L2 and L3 at one end and connected to the power supply at the other end; a resonant capacitor C2 connected to the output end of the resonant inductors L2 and L3 respectively; MOS transistors Q1 and Q2, the gates of MOS transistors Q1 and Q2 are connected to the output end of the resonant inductor L3 together, the drain is connected to the output end of the resonant inductor L2, and the source is grounded; a resonant capacitor C1, one end of which is connected to the power supply and the other end is grounded. The resonant inductor L2 and the resonant inductor L3 constitute a plate coil T1.

[0021] Specifically, the working principle of the ZVS circuit is: When powered on, the power supply turns on MOS tubes Q1 and Q2 through the choke coil L1. Due to the difference between the two MOS tubes, the currents of the two MOS tubes will be different. Assuming that the current of the switch tube Q1 is greater than the current of the MOS tube Q2, it can be seen that the gate voltage of the MOS tube Q1 is higher than the gate voltage of the MOS tube Q2. By connecting the gates and drains of the MOS tubes Q1 and Q2 to each other, the voltage at point c is lower than the voltage at point d. Therefore, the carrier coil T1 will generate an induced voltage with b being positive and c being negative, so positive feedback is formed through the carrier coil T1, turning on the MOS tube Q1 and turning off the MOS tube Q2, completing the startup process.

[0022] When the steady-state MOS tube Q1 is turned on, since the current of the carrier coil T1 in the previous cycle is from d to c, and the voltage across the resonant capacitor C2 is zero. Since the current cannot change suddenly, the current of the carrier coil T1 will charge the resonant capacitor C2, and the resonant capacitor C2 gradually becomes a voltage of d negative and c positive, and the sine becomes larger, and the sine of the current of the carrier coil T1 becomes smaller. At this time, the c voltage is pulled down to 0V by the MOS tube Q1, so the sine of the voltage at point d becomes larger, and the gate voltage of the MOS tube Q1 is controlled to be turned on by the drain voltage of the MOS tube Q2, and the MOS tube Q1 remains turned on.

[0023] At this time, the resonant capacitor C2 begins to discharge from d to c through the carrier coil T1, and the voltage of the resonant capacitor C2, that is, the voltage at point d, decreases sinusoidally, while the current of the carrier coil T1 increases sinusoidally from d to c. When the energy of the resonant capacitor C2 is basically discharged, the voltage at point d drops to about the MOS tube threshold voltage, causing the MOS tube Q1 to enter the amplification area. At this time, the discharge current of the resonant capacitor C2 to the carrier coil T1 winding from d to c reaches the maximum value. At the same time, because the MOS tube Q1 enters the amplification area, the voltage at point c gradually rises, causing the MOS tube Q2 to enter the amplification area as well. After the resonant capacitor C2 is discharged, the current of the carrier coil T1 winding from d to c reaches the maximum value, which will charge the resonant capacitor C1, charging the resonant capacitor C1 to a voltage of c positive and d negative, and at the same time, the voltage at both ends of the resonant capacitor C1 increases sinusoidally. At this time, the two MOS tubes enter the amplification area at the same time. Since the carrier coil T1 continuously charges the resonant capacitor C2, the voltage on the resonant capacitor C2 is c+d, which increases the gate voltage of the MOS tube Q2, and the gate of the MOS tube Q1 gradually decreases. At the same time, positive feedback is formed, and the MOS tube Q2 is turned on and the MOS tube Q1 is turned off. In the present invention, the conduction process of the MOS tube Q2 is similar to that of the MOS tube Q1.

[0024] Among them, the inductance value of the choke coil L1 is larger than that of the carrier coil T1, and the current of the choke coil L1 remains basically unchanged during the entire oscillation cycle. During the oscillation process, the choke coil L1 continuously replenishes power for the LC oscillator composed of the resonant inductor L2, the resonant inductor L3 and the resonant capacitor C2.

[0025] From the above analysis, it can be seen that the voltage of the MOS tube when it is turned on and off is usually its threshold voltage. The lower the threshold voltage, the shorter the response time, the lower the turn-on and turn-off voltages, and the smaller the loss. Through the voltage delay effect of the parallel capacitor, a conduction dead zone is formed, and the turn-off timing is accurately adjusted to make the turn-on and turn-off close to zero voltage, thereby reducing losses. When the circuit reaches oscillation equilibrium, the average voltage of the midpoint of the resonant inductor L2 and the resonant inductor L3 is equal to the power supply voltage V1. For a full-wave rectified signal with a peak value of E, its average value is 2E / π, so it can be deduced that 2E / π=V1. The peak value of the drain voltage of the MOS tube is twice the peak value of the midpoint voltage of the resonant inductor L2 and the resonant inductor L3. Therefore, the peak voltage of the sinusoidal half-wave rectification at both ends of the MOS tube is πV1. In this circuit, the power supply voltage V1 is 5V, so the peak voltage at both ends of the MOS tube is calculated to be about 15.7V, which is enough to ensure that the MOS tube is fully turned on.

[0026] Compared with the traditional ZVS circuit, the ZVS circuit of the present invention has a driving voltage provided by the power supply voltage through a series resistor, which increases the resistance loss, and the input voltage needs to be higher than the gate driving voltage of the MOS tube. The standard MOS tube usually requires a voltage of more than 5V to ensure full conduction. When the traditional ZVS circuit is powered by USB, the voltage is 5V, so an additional boost circuit is required, which increases the cost. The resonant inductor L2 and the resonant inductor L3 are made by the circuit routing on the circuit board, and there is no need to purchase additional coils, thereby reducing the cost.

[0027] In the present invention, Figure 3 As shown, in order to improve the energy transmission efficiency, the magnetic coupling resonant circuit uses the resonant frequency matching of the transmitting and receiving coils to maximize the energy transfer. Specifically, based on the LC resonant frequency being equal to f=1 / (2π√(LC)), the present invention adopts a matching method in which the LC resonant frequency of the receiving end is equal to the LC resonant frequency of the transmitting end to improve the efficient energy transfer.

[0028] In another embodiment of the present invention, the ZVS circuit uses LC parallel resonance to generate a sine wave of a fixed frequency. At this time, the carrier coil T1 couples the sine wave to the receiving end, and the receiving end uses LC resonance parallel connection with the same resonant frequency. The energy is efficiently transmitted through resonant frequency matching, thereby ensuring that the magnetic coupling resonant circuit can maintain a high coupling coefficient at a larger distance and a larger angle deviation. This means that even if there is a certain distance between the transmitting end and the receiving end or they are not completely aligned, energy can still be effectively transmitted. However, in order to ensure more efficient transmission of energy, the carrier coil T1 at the transmitting end and the coil at the receiving end are charged in a manner such that the center of the coil and the routing are facing each other with the maximum area, so as to reduce leakage flux and increase the coupling coefficient. Among them, the charging schematic diagram of the carrier coil T1 coil at the transmitting end and the coil at the receiving end is shown in FIG. Figure 4 shown.

[0029] In this embodiment, the transmitting end of the acne patch also includes: a USB power supply circuit and an overcurrent protection circuit. When the USB power supply module supplies power to the acne patch, the overcurrent protection circuit detects the power supply current to ensure that the acne patch is not damaged by overcurrent of the power supply current. The electrical signal output based on the overcurrent protection current is wirelessly transmitted to the receiving end through the carrier coil.

[0030] In the present invention, the receiving end of the acne patch also includes: a bridge rectifier circuit, a charging management circuit, a charging detection circuit, an LED control circuit, and a controller circuit. Figure 5 Based on the signal from the transmitting end, the charging detection circuit detects whether the receiving end receives the coupled radio signal. If there is a radio signal, the function is operated, that is, the LED control, controller control and other functions are performed. If no radio signal is detected, the LC resonant circuit and the bridge rectifier circuit are coupled and rectified to supply power to the charging management circuit and display the charging progress.

[0031] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

Claims

1. A ZVS magnetic coupling resonance type wireless charging electronic acne patch, characterized in that: include: A transmitting end and a receiving end, the transmitting end is provided with a ZVS circuit, and the receiving end is provided with a magnetic coupling resonance circuit; The ZVS circuit performs zero-voltage switching based on the input voltage signal. Based on the switching signal, the ZVS circuit matches the LC resonance frequency of the magnetic coupling resonance circuit through LC resonance, couples the switching electrical signal to the receiving end, and the receiving end performs corresponding control based on the received signal.

2. The ZVS magnetic coupling resonance wireless charging electronic acne patch according to claim 1, characterized in that: The ZVS circuit includes: resonant inductors L2 and L3 connected at one end; a choke coil L1 having one end connected to the input ends of the resonant inductors L2 and L3 and the other end connected to a power supply; a resonant capacitor C2 connected to the output ends of the resonant inductors L2 and L3 respectively; a MOS transistor Q1 and a MOS transistor Q2, wherein the gates of the MOS transistors Q1 and Q2 are connected together to the output end of the resonant inductor L3, the drains are connected to the output end of the resonant inductor L2, and the source is grounded; and a resonant capacitor C1, having one end connected to the power supply and the other end grounded.

3. The ZVS magnetic coupling resonance type wireless charging electronic acne patch according to claim 1, characterized in that: The resonant inductor L2 and the resonant inductor L3 form a carrier coil T1, and a coil is provided in the receiving end. The opening signal is coupled to the coil of the receiving end through the carrier coil T1.

4. The ZVS magnetic coupling resonance type wireless charging electronic acne patch according to claim 3 is characterized in that: The resonant inductor L2 and the resonant inductor L3 are manufactured by routing circuits on a circuit board.

5. The ZVS magnetic coupling resonance wireless charging electronic acne patch according to claim 3 is characterized in that: The plate coil T1 and the coil at the receiving end are charged by using the coil center and the routing to face each other with the maximum area.

6. The ZVS magnetic coupling resonance type wireless charging electronic acne patch according to claim 1, characterized in that: The LC resonance frequency in the ZVS circuit is the same as the LC resonance frequency in the magnetic coupling resonance circuit.

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