A magnetic resonance wireless charging system that suppresses system radiation and stray

Abstract

The present invention discloses a magnetic resonance wireless charging system that suppresses system radiation and stray. It improves the problem that the input impedance and coupling strength of the transmitting antenna vary greatly under different coupling distances, and do not match the output impedance of the power amplifier output, resulting in large reflection at the power amplifier end and low efficiency. Under different coupling conditions, due to the different coupling coefficients and coupling strengths between the transmitting antenna and the receiving antenna, the input impedance of the transmitting antenna at the transmitting end varies greatly at different distances, while the output impedance of the power amplifier varies very little within a certain power range, resulting in a serious mismatch between the input impedance of the transmitting antenna and the output impedance of the power amplifier at some coupling distances, which aggravates spatial stray. The present invention matches the input impedance of the antenna to the output impedance variation range of the power amplifier through impedance matching based on the different input impedances of the antenna at different coupling distances, thereby improving overall efficiency and improving spatial stray.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless power transmission, and in particular relates to a magnetic resonance wireless charging system that suppresses system radiation and stray radiation. Background Art

[0002] With the continuous development of electronic information technology, automation and control technology, the Internet of Things, and smart homes, a wide variety of home appliances, consumer electronics, and mobile communication devices have become widely popular. However, traditional home appliances rely on wired connections between power cords and power outlets for charging. Electronic devices with built-in batteries also require a wired connection between charging cables and power outlets. Therefore, wires that power electronic devices are ubiquitous. With the increasing demand for portable devices that can be fully wirelessly charged, the research and application of wireless energy transfer technologies have rapidly become a focus of academic and industrial circles both domestically and internationally. Currently, there are three main types of wireless charging technologies recognized in the industry: the Qi standard promoted by the WPC Alliance, also known as magnetic induction coupling; resonant coupling technology promoted by the Airfuel Alliance; and electromagnetic radiation-based wireless energy transfer. Compared to magnetic induction technology, resonant coupling technology offers significant advantages in charging distance, spatial freedom, one-to-many charging, and power scalability. Compared to electromagnetic radiation-based wireless energy transfer, magnetic resonant coupling technology offers greater practical application value in terms of energy conversion efficiency, transmission power, and electromagnetic safety. Currently, this technology has been gradually applied to smart wearables, sweeping robots, AGVs, and other devices, giving them wireless charging capabilities, improving their safety and intelligence, and enhancing the user experience. Furthermore, the application of magnetic resonance coupling technology in the smart home sector will also subvert the usage patterns of traditional home appliances, mobile communication devices, and consumer electronics. Using the home as a platform, magnetic resonance wireless charging technology and hidden wiring technology will completely remove all power cords from the living area of ​​the home, allowing devices to be wirelessly charged or continuously powered, improving home safety, convenience, and comfort, and creating an efficient, environmentally friendly, and energy-saving living environment.

[0003] Wireless energy transmission modes and mechanisms can be roughly divided into three types: magnetic induction coupling, electromagnetic radiation, and magnetic resonance coupling. Compared with electromagnetic radiation, magnetic resonance coupling has advantages in safety and transmission efficiency; compared with magnetic induction coupling, it has advantages in transmission distance. As the market continues to upgrade the application scenarios of magnetic resonance wireless charging, some fields require that the load can be charged normally even when the moving distance and position are large, and it is necessary to pass RF test standards and EMC / EMI certification. The currently disclosed magnetic resonance wireless charging systems have the following disadvantages and cannot meet the needs:

[0004] (1) The design of the magnetic resonance wireless charging system is based on the system working in the optimal coupling state. When the receiving end moves a long distance and a large position, the magnetic resonance wireless charging system will work in the over-coupling state and the under-coupling state. When the system works in the over-coupling state and the under-coupling state, the efficiency is low, the space radiation is increased, and the electromagnetic compatibility of the system cannot meet the safety requirements.

[0005] (2) The receiving end of the magnetic resonance wireless charging system is generally designed to connect a receiving coil to an impedance mapping circuit to form a receiving antenna system, which is then connected to a rectifier circuit to convert radio frequency energy into direct current energy to power the electrical equipment. This will cause impedance mismatch between the rectifier circuit and the receiving antenna system, and the rectifier circuit in the switching state will worsen the high-frequency stray signal, and radiate the high-frequency stray signal into space through the receiving coil, making the magnetic resonance wireless charging system unable to pass the RF test standard. Summary of the Invention

[0006] In view of the above-mentioned deficiencies in the prior art, the present invention provides a magnetic resonance wireless charging system that suppresses system radiation and stray radiation, and solves the problems existing in the prior art.

[0007] In order to achieve the above-mentioned purpose of the invention, the technical solution adopted by the present invention is: a magnetic resonance wireless charging system that suppresses system radiation and stray radiation, including an adapter, a magnetic resonance transmitting module and a magnetic resonance receiving module;

[0008] The magnetic resonance transmission module includes a DC / DC power supply, a radio frequency power amplifier circuit, a radio frequency filter circuit 1, several secondary mapping circuits composed of LC matching and capacitor matching networks, several primary mapping circuits composed of LC matching networks, a transmitting Bluetooth communication circuit, and a transmitting antenna; the DC / DC power supply is electrically connected to the adapter, the radio frequency power amplifier circuit, and the transmitting Bluetooth communication circuit respectively, the radio frequency power amplifier circuit is electrically connected to the radio frequency filter circuit 1, the radio frequency filter circuit 1 is electrically connected to the secondary mapping circuits B1-Bn respectively, the secondary mapping circuits B1-Bn are electrically connected to each other and to the primary mapping circuits A1-An respectively, and the primary mapping circuits A1-An are electrically connected to the transmitting antenna respectively;

[0009] The magnetic resonance receiving module includes a receiving antenna, a common mode filter 1, a receiving capacitor matching circuit, a radio frequency filter circuit 2, a common mode filter 2, a rectifier and voltage stabilization circuit, and a load electrically connected in sequence. It also includes a receiving Bluetooth communication circuit. The receiving antenna is communicatively connected to the transmitting antenna, the receiving Bluetooth communication circuit is communicatively connected to the transmitting Bluetooth communication circuit, and the receiving Bluetooth communication circuit is electrically connected to the rectifier and voltage stabilization circuit.

[0010] Furthermore, the input end and the input end of the primary mapping circuit are both provided with switches, and the input end of the secondary mapping circuit is provided with a switch.

[0011] Furthermore, the primary mapping circuit is used to reduce the input impedance of the antenna from a variation range, and the secondary mapping circuit is used to further reduce the input impedance of the antenna from a variation range.

[0012] Furthermore, if the antenna impedance variation is within a system-set threshold, a set of primary mapping circuits is used to match the input impedance of the power amplifier with the input impedance of the transmitting antenna;

[0013] If the antenna impedance variation exceeds a system-set threshold, multiple sets of primary mapping circuits or a combination of primary and secondary mapping circuits are used to match the input impedance of the power amplifier with the input impedance of the transmitting antenna;

[0014] If the distance between the receiving antenna and the transmitting antenna changes beyond a system-set threshold, multiple sets of primary mapping circuits and multiple sets of secondary mapping circuits are used to match the input impedance of the power amplifier with the input impedance of the transmitting antenna.

[0015] Furthermore, the common-mode filter 1 and the common-mode filter 2 are respectively the primary filter and the secondary hybrid filter of the magnetic resonance receiving module; the cutoff frequency of the primary filter is greater than 6.78 MHz, and is used to filter out the out-of-band high-frequency harmonics and stray signals received by the receiving antenna; the secondary hybrid filter is used to filter out the high-frequency harmonics and stray signals caused by the nonlinearity and deterioration of the switching characteristics of the rectifier diode in the receiving capacitor matching circuit.

[0016] Furthermore, both the common-mode filter 1 and the common-mode filter 2 may be a combination of multiple common-mode filters.

[0017] The beneficial effects of the present invention are:

[0018] (1) The present invention is provided with a plurality of primary mapping circuits and a plurality of secondary mapping circuits. By combining different numbers of primary mapping circuits and secondary mapping circuits, the impedance matching between the transceiver system and the RF power amplifier source is changed to improve the system conversion efficiency and thus reduce high-frequency radiation.

[0019] (2) The present invention suppresses high-frequency spurious signals by adding a filtering circuit at the receiving end, thereby reducing high-frequency spurious radiation in space. The receiving filter is composed of a primary filter and a secondary hybrid filter. The primary filter has a cutoff frequency above 6.78 MHz and filters out high-frequency harmonics out of the band. The secondary hybrid filter is composed of a common-mode filter and a radio frequency filter. The hybrid filter can suppress the nonlinearity of the diode and the high-frequency spurious signals caused by the deterioration of the switching characteristics of the diode. In combination with the shielding cover, the high-frequency spurious signals are radiated into space.

[0020] (3) The present invention provides a magnetic resonance wireless charging system that suppresses system radiation and stray signals, effectively suppressing system radiation and stray signals, and suppressing high-frequency stray signals to meet RF certification standards and safety standards in various regions. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of a magnetic resonance wireless charging system that suppresses system radiation and stray emissions.

[0022] Figure 2 It is the RF power amplifier source circuit.

[0023] Figure 3 It is the secondary mapping circuit B1.

[0024] Figure 4 It is the secondary mapping circuit B2.

[0025] Figure 5 This is the primary mapping circuit A1.

[0026] Figure 6 This is the primary mapping circuit A2.

[0027] Figure 7 This is the primary mapping circuit A3.

[0028] Figure 8 This is the primary mapping circuit A4.

[0029] Figure 9 For auxiliary power supply.

[0030] Figure 10 For transmitting Bluetooth communication circuit.

[0031] Figure 11 For receiving matching and filtering circuit.

[0032] Figure 12 It is a rectifier and filter circuit.

[0033] Figure 13 It is a DC / DC voltage regulator.

[0034] Figure 14 It is a filtering, current sampling and output control circuit.

[0035] Figure 15 Power supply for Bluetooth circuit.

[0036] Figure 16 It is the output sampling circuit.

[0037] Figure 17 For receiving Bluetooth communication circuit.

[0038] Figure 18 This is the schematic diagram of an implementation example with only a capacitor matching network at the transmitter end.

[0039] Figure 19 Schematic diagram of a specific implementation example of adding a primary mapping circuit to the transmitter.

[0040] Figure 20 Schematic diagram of a specific implementation case for adding primary and secondary mapping circuits to the transmitter.

[0041] Figure 21 Schematic diagram of a specific implementation case that introduces a two-stage mapping circuit at the transmitter and no filtering circuit at the receiver.

[0042] Figure 22 Schematic diagram of a specific implementation case that introduces a two-stage mapping circuit at the transmitter and adds a primary filtering circuit at the receiver.

[0043] Figure 23 Schematic diagram of a specific implementation case in which a two-stage mapping circuit is introduced at the transmitter and a primary filter and a hybrid filter are added to the receiver.

[0044] Figure 24 Experimental results when the primary and secondary mapping circuits are added to the transmitter and only the capacitor matching network is used on the receiver.

[0045] Figure 25 Experimental results when primary and secondary mapping circuits are added to the transmitter, and a capacitor matching network and hybrid filter are included on the receiver.

[0046] Figure 26 The experimental results are shown when the primary mapping circuit and the secondary mapping circuit are added to the transmitter, and the capacitor matching network, the hybrid filter, and the primary filter are included in the receiver. DETAILED DESCRIPTION

[0047] The specific embodiments of the present invention are described below to facilitate understanding of the present invention by those skilled in the art. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, as long as various changes are within the spirit and scope of the present invention as defined and determined by the appended claims, these changes are obvious, and all inventions and creations utilizing the concepts of the present invention are protected.

[0048] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0049] Example 1

[0050] like Figure 1 As shown, a magnetic resonance wireless charging system for suppressing system radiation and stray emissions includes an adapter, a magnetic resonance transmitting module, and a magnetic resonance receiving module;

[0051] The magnetic resonance transmission module includes a DC / DC power supply, a radio frequency power amplifier circuit, a radio frequency filter circuit 1, several secondary mapping circuits composed of LC matching and capacitor matching networks, several primary mapping circuits composed of LC matching networks, a transmitting Bluetooth communication circuit, and a transmitting antenna; the DC / DC power supply is electrically connected to the adapter, the radio frequency power amplifier circuit, and the transmitting Bluetooth communication circuit respectively, the radio frequency power amplifier circuit is electrically connected to the radio frequency filter circuit 1, the radio frequency filter circuit 1 is electrically connected to the secondary mapping circuits B1-Bn respectively, the secondary mapping circuits B1-Bn are electrically connected to each other and to the primary mapping circuits A1-An respectively, and the primary mapping circuits A1-An are electrically connected to the transmitting antenna respectively;

[0052] The magnetic resonance receiving module includes a receiving antenna, a common mode filter 1, a receiving capacitor matching circuit, a radio frequency filter circuit 2, a common mode filter 2, a rectifier and voltage stabilization circuit, and a load electrically connected in sequence. It also includes a receiving Bluetooth communication circuit. The receiving antenna is communicatively connected to the transmitting antenna, the receiving Bluetooth communication circuit is communicatively connected to the transmitting Bluetooth communication circuit, and the receiving Bluetooth communication circuit is electrically connected to the rectifier and voltage stabilization circuit.

[0053] The input and output terminals of the primary mapping circuit are both provided with switches, and the input terminal of the secondary mapping circuit is provided with a switch. The primary mapping circuit is used to reduce the input impedance of the antenna from a variation range, and the secondary mapping circuit is used to further reduce the input impedance of the antenna from a variation range.

[0054] If the antenna impedance change is within the system-set threshold, a set of primary mapping circuits is used to match the power amplifier input impedance with the input impedance of the transmitting antenna; if the antenna impedance change exceeds the system-set threshold, multiple sets of primary mapping circuits or a combination of primary mapping circuits and secondary mapping circuits are used to match the power amplifier input impedance with the input impedance of the transmitting antenna; if the distance change between the receiving antenna and the transmitting antenna exceeds the system-set threshold, multiple sets of primary mapping circuits and multiple sets of secondary mapping circuits are used to match the power amplifier input impedance with the input impedance of the transmitting antenna.

[0055] Common-mode filter 1 and common-mode filter 2 are the primary and secondary hybrid filters of the magnetic resonance receiving module, respectively. The primary filter has a cutoff frequency greater than 6.78 MHz and is used to filter out-of-band high-frequency harmonics and spurious signals received by the receiving antenna. The secondary hybrid filter is used to filter out high-frequency harmonics and spurious signals caused by the nonlinearity and switching characteristics of the rectifier diode in the receiving capacitor matching circuit. Both common-mode filter 1 and common-mode filter 2 can be a combination of multiple common-mode filters.

[0056] The technical solution of the present invention is to improve the system conversion efficiency by changing the impedance matching between the transceiver system and the radio frequency power amplifier source, thereby reducing high-frequency radiation. The magnetic resonance wireless charging system will present three coupling states according to the distance between the transmitter and the receiver: 1. Over-coupling state; 2. Under-coupling state; 3. Optimal coupling state. Under different working conditions, the impedance matrix parameters of the transmitter and receiver vary greatly. The general magnetic resonance wireless charging system will design the primary mapping circuit according to the optimal coupling state. When there is only a capacitor matching method, there is a matching blind spot. When the transceiver distance and position change, the magnetic resonance wireless charging system will work in the over-coupling state and the under-coupling state. At this time, the input impedance matrix parameters of the transceiver system change, resulting in a decrease in the conversion efficiency of the system. An impedance matching circuit can be added to compensate for the matching blind spot of the capacitor matching to ensure the best conversion efficiency under various coupling states. After the transmitting capacitor matching network is set, the receiving antenna is moved. At this time, the input impedance parameters of the antenna will change, affecting the matching degree between the power amplifier source and the antenna system. At this time, an impedance matching circuit can be added to map the transmitting antenna impedance to a smaller range of target impedance. On this basis, a secondary mapping circuit is added. At this time, the antenna can be transformed to a value closer to the target impedance through two-stage mapping, forming a conjugate impedance match with the output impedance of the power amplifier source, thereby improving transmission efficiency.

[0057] If the position and distance between the transmitter and receiver change slightly, only the primary mapping circuit is needed to make the antenna impedance close to the target impedance. If the distance and position between the transmitter and receiver change significantly, multiple sets of primary mapping circuits can be used to map the impedance to the target value. If the distance and position between the transmitter and receiver change significantly, multiple sets of primary mapping circuits can be used to map the impedance to a smaller range of the target impedance, and then a secondary mapping circuit can be added to map the impedance to an even smaller range of the target impedance. Through testing, it was found that the impedance change at the transmitter caused by the change at the receiving end was not large, so a mapping circuit was not added at the receiving end.

[0058] Furthermore, filtering circuits are added to the receiving end to suppress high-frequency spurious signals and reduce high-frequency spurious radiation within the space. The receiving filter consists of a primary filter and a secondary hybrid filter. The primary filter, with a cutoff frequency above 6.78 MHz, removes out-of-band high-frequency harmonics. The secondary hybrid filter comprises a common-mode filter and an RF filter. The hybrid filter suppresses high-frequency spurious signals caused by diode nonlinearity and deterioration of the diode's switching characteristics. Combined with a shielding cover, the hybrid filter prevents high-frequency spurious signals from radiating into the space. These two factors suppress high-frequency spurious signals, ensuring compliance with RF certification standards and regional safety regulations.

[0059] like Figure 2 As shown, in this embodiment, the radio frequency power amplifier circuit includes an input filter circuit unit, a radio frequency power amplification circuit unit, a radio frequency filter circuit unit, a power supply circuit unit and a power amplifier source driving circuit unit;

[0060] The input filter circuit unit includes a DC / DC output voltage terminal Vds, capacitors C10-13, a resistor R5 and an inductor L1; the DC / DC output voltage terminal Vds is respectively connected to the positive electrode of the polarized capacitor C10, the grounded capacitor C11-13, the grounded resistor R5 and one end of the inductor L1, and the negative electrode of the polarized capacitor C10 is grounded.

[0061] The RF power amplifier circuit unit includes a power amplifier tube Q3, a capacitor C7, a capacitor C1-2, a capacitor C15 and an inductor L2-3; the drain of the power amplifier tube Q3 is respectively connected to the other end of the inductor L1, the grounded capacitor C7 and one end of the inductor L2, the gate of the power amplifier tube Q3 is connected to the QD_EN contact, the source of the power amplifier tube Q3 is grounded, the other end of the inductor L2 is respectively connected to one end of the capacitor C1 and one end of the capacitor C3, the other end of the capacitor C1 is respectively connected to the other end of the capacitor C3 and one end of the inductor L3, and the other end of the inductor L3 is connected to the grounded capacitor C15.

[0062] The RF filter circuit unit includes capacitors C16-19, capacitors C5-6, inductors L4-5 and capacitor C2. One end of the inductor L4 is respectively connected to the grounded capacitor C16 and one end of the capacitor C5, and the other end of the inductor L4 is respectively connected to the grounded capacitors C17-18, the other end of the capacitor C5, one end of the capacitor C6 and one end of the inductor L5. The other end of the inductor L5 is respectively connected to the other end of the capacitor C6, the grounded capacitor C19 and one end of the capacitor C2, and the other end of the capacitor C2 is connected to the RF contact.

[0063] The power supply circuit unit includes a DC / DC output voltage terminal Vds, a chip N4 (TPS40170RGYR) and capacitors C29-31; the third pin of the chip N4 is respectively connected to the DC / DC output voltage terminal Vds and the grounding capacitor C29, its second pin is grounded, and its third pin is respectively connected to the grounding capacitors C30-31.

[0064] The power amplifier source drive circuit unit includes capacitors C6-7, chip N3 (BL8023FCB6TR), capacitor C33, and chip X1. Pin 1 of chip N3 is connected to pin 1 of chip N4, pin 2 of chip N3 is connected to one end of resistor R6, pin 3 of chip N3 is connected to one end of resistor R7, pins 4-5 of chip N3 are grounded, and pin 6 of chip X1 is connected to pin 3 of chip X1. The other end of resistor R6 is respectively connected to the other end of resistor R7 and the QD_EN contact. Pin 2 of chip X1 is grounded, and pin 4 of chip X1 is respectively connected to the 3V3 contact and grounded capacitor C33. The 3V3 contact is connected to a 3.3V voltage.

[0065] In this embodiment, the secondary mapping circuit includes B1-B2, and the primary mapping circuit includes A1-A4.

[0066] like Figure 3 As shown, the secondary mapping circuit B1 includes a resistor R1, a resistor R3, a transistor Q1, a capacitor C1, a capacitor C8, a diode D1, a chip N1 and an LC matching circuit unit B1. The first pin of the chip N1 (LL4148) is connected to the DC / DC output voltage terminal Vds, and its 3rd to 6th pins are connected to the RF1 contact, the Match_H1 contact, the Match_H contact and the RF contact in sequence. The 8th pin is respectively connected to the collector of the transistor Q1, the grounded capacitor C8 and the cathode of the diode D1. The anode of the diode D1 and the emitter of the transistor Q1 are grounded. The base of the transistor Q1 is respectively connected to the grounded resistor R3, the grounded capacitor C20 and one end of the resistor R1. The other end of the resistor R1 is connected to the CH6 contact.

[0067] The LC matching circuit unit B1 includes capacitors C22, C24, C26, C28, and inductor L6. One end of inductor L6 is connected to grounded capacitors C22 and C24, respectively, and the Match_H node. The other end of inductor L6 is connected to grounded capacitors C26 and C28, respectively, and the Match_H1 node. Capacitance and inductance values ​​of capacitors C22, C24, C26, C28, and inductor L6 are determined based on the actual impedance matrix parameters. Based on the impedance matrix parameters, one set of capacitors C22, C24, C26, and C28 is selected for impedance matching, while another set remains unconnected.

[0068] like Figure 4 As shown, the secondary mapping circuit B2 includes a resistor R2, a resistor R4, a transistor Q2, a capacitor C21, a capacitor C9, a diode D2, a chip N2 (LL4148) and an LC matching circuit unit B2. The first pin of the chip N2 is connected to the DC / DC output voltage terminal Vds, and its 3-6 pins are connected to the RF contact, the Match_L contact, the Match_L1 contact and the RF1 contact in sequence. The 8th pin is connected to the collector of the transistor Q2, the grounded capacitor C9 and the cathode of the diode D2, respectively. The anode of the diode D2 and the emitter of the transistor Q2 are grounded. The base of the transistor Q2 is connected to the grounded resistor R4, the grounded capacitor C21 and one end of the resistor R2, respectively. The other end of the resistor R2 is connected to the CH5 contact.

[0069] The LC matching circuit unit B2 includes capacitors C23, C25, C27, C32, and inductor L7. One end of inductor L7 is connected to grounded capacitors C23, C25, and the Match_L node, respectively. The other end of inductor L7 is connected to grounded capacitors C27, C32, and the Match_L1 node, respectively. Capacitance and inductance values ​​of capacitors C23, C25, C27, C32, and inductor L7 are determined based on the actual impedance matrix parameters. Based on the impedance matrix parameters, one set of capacitors C23, C25, C27, and C32 is selected for impedance matching, while another set remains unconnected.

[0070] like Figure 5 As shown, the primary mapping circuit A1 includes a resistor R8, a resistor R12, a capacitor C38, a transistor Q4, a capacitor C34, a diode D3, a chip N5 (LL4148), an LC matching circuit unit A1, and a capacitor matching network A1. Pin 1 of chip N5 is connected to the DC / DC output voltage terminal Vds, and pins 3-6 of chip N5 are connected to the RFout connection, the COIL3 connection, the Match2 connection, and the RF1 connection in sequence. Pin 8 of chip N5 is connected to the cathode of diode D3, the grounded capacitor C34, and the collector of transistor Q4, respectively. The anode of diode D3 and the emitter of transistor Q4 are grounded. The base of transistor Q4 is connected to the grounded capacitor C38, the grounded resistor R12, and one end of resistor R8, respectively. The other end of resistor R8 is connected to the CH1 connection.

[0071] The LC matching circuit unit A1 includes capacitor C42, capacitor C46, ​​capacitor C50, capacitor C54 and inductor L8; the capacitor matching network A1 includes capacitor C145, capacitor C66, capacitor C70 and capacitors C58-89; one end of inductor L8 is respectively connected to grounded capacitor C42, grounded capacitor C46 and Match2 connection, the other end of inductor L8 is respectively connected to grounded capacitor C50, grounded capacitor C54, one end of capacitor C58 and one end of capacitor C59, the other end of capacitor C59 is respectively connected to the other end of capacitor C58, one end of capacitor C66, one end of capacitor C70 and COIL3 connection, and the other end of capacitor C66 is respectively connected to the other end of capacitor C70, grounded capacitor C145 and coil connection. Among them, C42, C46, ​​C50, C54 and inductor L8 will determine the capacitance and inductance values ​​according to the actual required impedance matrix parameters. C42, C46 and C50, C54 will select a group of capacitors to participate in impedance matching according to the impedance matrix parameters, and one group will not be connected.

[0072] like Figure 6As shown, the primary mapping circuit A2 includes a resistor R9, a resistor R13, a capacitor C39, a transistor Q5, a capacitor C35, a diode D4, a chip N6 (LL4148), an LC matching circuit unit A2, and a capacitor matching network A2. Pin 1 of chip N5 is connected to the DC / DC output voltage terminal Vds, and pins 3-6 of chip N5 are connected to the RF1 connection, the Match3 connection, the COIL5 connection, and the RFout connection in sequence. Pin 8 of chip N5 is connected to the cathode of diode D4, the grounded capacitor C35, and the collector of transistor Q5, respectively. The anode of diode D4 and the emitter of transistor Q5 are grounded. The base of transistor Q5 is connected to the grounded capacitor C39, the grounded resistor R13, and one end of resistor R9, respectively. The other end of resistor R9 is connected to the CH2 connection.

[0073] The LC matching circuit unit A2 includes capacitor C43, capacitor C47, capacitor C51, capacitor C55 and inductor L9; the capacitor matching network A1 includes capacitor C146, capacitor C67, capacitor C71 and capacitors C60-61; one end of the inductor L9 is respectively connected to the grounded capacitor C43, the grounded capacitor C47 and the Match3 connection, the other end of the inductor L9 is respectively connected to the grounded capacitor C51, the grounded capacitor C55, one end of the capacitor C60 and one end of the capacitor C61, the other end of the capacitor C60 is respectively connected to the other end of the capacitor C61, one end of the capacitor C67, one end of the capacitor C71 and the COIL5 connection, and the other end of the capacitor C67 is respectively connected to the other end of the capacitor C71, the grounded capacitor C146 and the coil connection. Among them, C43, C47, C51, C55 and inductor L9 will determine the capacitance and inductance values ​​according to the actual required impedance matrix parameters. C43, C47 and C51, C55 will select a group of capacitors to participate in impedance matching according to the impedance matrix parameters, and one group will not be connected.

[0074] like Figure 7 As shown, the primary mapping circuit A3 includes a resistor R10, a resistor R14, a capacitor C40, a transistor Q6, a capacitor C36, a diode D5, a chip N7 (LL4148), an LC matching circuit unit A3, and a capacitor matching network A3. Pin 1 of chip N7 is connected to the DC / DC output voltage terminal Vds, and pins 3-6 of chip N7 are connected to the RFout terminal, the COIL7 terminal, the Match4 terminal, and the RF1 terminal in sequence. Pin 8 of chip N7 is connected to the cathode of diode D5, the grounded capacitor C36, and the collector of transistor Q6, respectively. The anode of diode D5 and the emitter of transistor Q6 are grounded. The base of transistor Q6 is connected to the grounded capacitor C40, the grounded resistor R14, and one end of resistor R10, respectively. The other end of resistor R10 is connected to the CH3 terminal.

[0075] The LC matching circuit unit A3 includes capacitor C44, capacitor C48, capacitor C52, capacitor C56 and inductor L10; the capacitor matching network A3 includes capacitor C143, capacitor C68, capacitor C72 and capacitor C62-63; one end of the inductor L10 is respectively connected to the grounded capacitor C44, the grounded capacitor C48 and the Match4 connection point, the other end of the inductor L10 is respectively connected to the grounded capacitor C52, the grounded capacitor C56, one end of the capacitor C62 and one end of the capacitor C63, the other end of the capacitor C62 is respectively connected to the other end of the capacitor C63, one end of the capacitor C68, one end of the capacitor C72 and the COIL7 connection point, and the other end of the capacitor C68 is respectively connected to the other end of the capacitor C72, the grounded capacitor C143 and the coil connection point. Among them, C44, C48, C52, C56 and inductor L10 will determine the capacitance and inductance values ​​according to the actual required impedance matrix parameters. C44, C48 and C52, C56 will select a group of capacitors to participate in impedance matching according to the impedance matrix parameters, and one group will not be connected.

[0076] like Figure 8 As shown, the primary mapping circuit A4 includes a resistor R11, a resistor R15, a capacitor C41, a transistor Q7, a capacitor C37, a diode D6, a chip N8 (LL4148), an LC matching circuit unit A4, and a capacitor matching network A4. Pin 1 of chip N8 is connected to the DC / DC output voltage terminal Vds, and pins 3-6 of chip N8 are connected to the RF1 connection, the Match1 connection, the COIL1 connection, and the RFout connection in sequence. Pin 8 of chip N8 is connected to the cathode of diode D6, the grounded capacitor C37, and the collector of transistor Q7, respectively. The anode of diode D6 and the emitter of transistor Q7 are grounded. The base of transistor Q7 is connected to the grounded capacitor C41, the grounded resistor R15, and one end of resistor R11, respectively. The other end of resistor R11 is connected to the CH4 connection.

[0077] The LC matching circuit unit A4 includes capacitor C45, capacitor C49, capacitor C53, capacitor C57 and inductor L11; the capacitor matching network A4 includes capacitor C144, capacitor C69, capacitor C73 and capacitors C64-65; one end of the inductor L11 is respectively connected to the grounded capacitor C45, the grounded capacitor C49 and the Match1 connection, the other end of the inductor L11 is respectively connected to the grounded capacitor C53, the grounded capacitor C57, one end of the capacitor C64 and one end of the capacitor C65, the other end of the capacitor C64 is respectively connected to the other end of the capacitor C65, one end of the capacitor C69, one end of the capacitor C73 and the COIL1 connection, and the other end of the capacitor C69 is respectively connected to the other end of the capacitor C73, the grounded capacitor C144 and the coil connection. Among them, C45, C49, C53, C57 and inductor L11 will determine the capacitance and inductance values ​​according to the actual required impedance matrix parameters. C45, C49 and C53, C57 will select a group of capacitors to participate in impedance matching according to the impedance matrix parameters, and one group will not be connected.

[0078] like Figure 9 As shown, in this embodiment, an auxiliary power supply circuit is provided for outputting a 3.3V voltage. The auxiliary power supply circuit includes capacitors C4, C14, C97-98, and chip N9 (MC7812CDTRKG). Pin 3 of chip N9 is connected to the DC / DC output voltage terminal Vds, grounded capacitors C4, and C14, respectively. Pin 1 of chip N9 is grounded, and pin 3 of chip N9 is connected to grounded capacitors C97-98 and the 3V3 contact.

[0079] like Figure 10As shown, the transmitting Bluetooth communication circuit includes chip U1 (MFRC52202HN1,151), capacitors C74-96, ferrite beads FB1, resistors R16, diodes D7, inductors L12-14, Bluetooth antenna ANT1 and terminal J1 (PZ254V-11-04P); the 9th pin of chip U1 is connected to its 18th-19th pins, 3V3_1 node, grounded capacitors C75-80, the cathode of diode D7 and one end of ferrite beads FB1 respectively. Its 12th pin is connected to its 28th pin and grounded capacitors C86-91 respectively, its 8th pin is connected to its 13th pin and grounded capacitors C92-93 respectively, its 7th and 33rd pins are grounded, its 25th pin is connected to the nRESET contact, grounded capacitor C94 and one end of resistor R16 respectively, its 5th pin is connected to the SWS contact, its 10th-11th pins are connected to both ends of inductor L12 respectively, its 27th pin is connected to one end of inductor L14, grounded capacitor C94 and one end of resistor R16 respectively. C82 is connected to one end of capacitor C81, its 26th pin is connected to grounded capacitor C85 and the other end of inductor L14 respectively, its 23rd, 24th, 31st, 32nd, 1st and 2nd pins are connected to CH6-1 contact in sequence, its 29th pin is connected to the 1st pin of chip Y1 and grounded capacitor C95 respectively, its 30th pin is connected to the 3rd pin of chip Y1 and grounded capacitor C96 respectively; the 2nd and 4th pins of chip Y1 are both grounded, the positive pole of diode D7 is grounded, and the magnetic bead F is connected to the grounded pin. The other end of B1 is connected to the grounded capacitor C74 and the 3V3 terminal respectively, the other end of the resistor R16 is connected to the 3V3_1 terminal, the other end of the capacitor C81 is connected to the grounded capacitor C83 and one end of the inductor L13 respectively, and the other end of the inductor L13 is connected to the grounded capacitor C84 and the Bluetooth antenna ANT1 respectively and to ground; pins 1-4 of the terminal J1 are connected to the nRESET terminal, AGND terminal, SWS terminal and 3V3 terminal respectively, and its pin 3 is grounded.

[0080] like Figure 11The figure shows the specific connection relationship between the common mode filter 1, the receiving capacitor matching circuit, the radio frequency filter circuit 2 and the common mode filter 2. Among them, the common mode filter 1 (SDCW2012-2-900TF) is a primary filter, and its 3rd pin is the same-name end of the 4th pin, and its 3rd and 4th pins are respectively connected to the two ends of the receiving antenna. The receiving capacitor matching circuit includes capacitors C136-142, the 1st pin of the common mode filter 1 is respectively connected to one end of the capacitors C136, 137, 140, and 142, and the 2nd pin of the common mode filter 1 is respectively connected to one end of the capacitors C138-139 and the other end of the capacitors C140-142; the radio frequency filter circuit 2 includes capacitors C124, capacitor C128, capacitors C131-134 and inductors L19-L20, and one end of the inductor L19 is respectively connected to the other end of the capacitors C136-137, the capacitors C138-139 and the other end of the capacitors C140-142. One end of C133-134, one end of capacitor C131, and pin 4 of common-mode filter 2 are connected. The other end of inductor L19 is connected to the other end of capacitor C131, one end of capacitor C124, and one end of capacitor C128. One end of inductor L20 is connected to the other ends of capacitors C138-139, the other ends of capacitors C133-134, and one end of capacitor C132. The other end of inductor L20 is connected to the other ends of capacitors C132, C124, and C128, and pin 3 of common-mode filter 2. Pins 1-2 of common-mode filter 2 are connected to the rectifier and voltage regulator circuit.

[0081] like Figure 12 The rectifier and voltage-stabilizing circuit includes capacitors C102-107, capacitor C113, and diodes D9-12; the anode of diode D9 is respectively connected to the cathode of diode D11 and the first pin of common-mode filter 2, and the anode of diode D10 is respectively connected to the cathode of diode D12 and the second pin of common-mode filter 2; the cathode of diode D9 is respectively connected to one end of capacitor C113, the cathode of diode D10, grounded capacitor C102-107, and VIN contact, and the anode of diode D11 is respectively connected to the anode of diode D12 and the other end of capacitor C113 and to ground.

[0082] like Figure 13As shown, in this embodiment, a DC-DC voltage stabilizing source circuit is provided after the rectifier voltage stabilizing circuit. The DC-DC voltage stabilizing source circuit includes capacitor C108, diode Z1, resistor R19, capacitor C111, resistor R26, chip N11 (UC3845ADTR), resistors R20-21, resistor R25, resistor R27, capacitor C99 and inductor L15; the 8th pin of chip N1 is respectively connected to the grounded capacitor C108, resistor R19 and VIN contact, the 12th pin is respectively connected to the other end of resistor R19 and the negative electrode of diode Z1, the 6th pin is connected to the grounded capacitor C111, and the 1st pin is connected to the grounded capacitor C111. Pin 1 is connected to the grounded capacitor R26, its pin 7 is grounded, its pin 1 is connected to one end of the capacitor C99, its pin 2 is respectively connected to one end of the inductor L15 and the other end of the capacitor C99, its pin 5 is connected to the grounded resistor R20, and its pin 4 is connected to one end of the resistor R25; the anode of the diode Z1 is grounded, the other end of the inductor L15 is respectively connected to the con1 contact and one end of the resistor R21, and the other end of the resistor R25 is respectively connected to the grounded resistor R27, the other end of the resistor R21 and the con2 contact.

[0083] like Figure 14 As shown, in this embodiment, a DC filter circuit, an output current sampling circuit and an output control switch are further provided after the DC-DC voltage regulator circuit. The DC filter circuit includes capacitors C100-101, the output current sampling circuit includes chip N12 (INA181A2IDBVT), resistor RS1, resistors R28-29, capacitor C110, resistor R31 and diode D8, and the output control switch includes chip N10 (2N7002), chip N13 (2N7002), resistor R17, resistor R23 and capacitor C112; the 4th pin of chip N12 is respectively connected to the grounded capacitor C100-101, the con1 contact and one end of the resistor RS1, and its 5th pin is respectively connected to the other end of the resistor RS1, the 2nd pin of chip N10 and the One end of the chip N10 is connected, its 6th pin is respectively connected to one end of the resistor R28 and one end of the resistor R31, its 1st pin is grounded, its 2nd pin is connected to the grounded capacitor C110, and its 3rd pin is connected to its 4th pin; the other end of the resistor R31 is connected to the IF contact, the other end of the resistor R28 is respectively connected to the grounded resistor R29 and the positive electrode of the diode D8, and the negative electrode of the diode D8 is connected to the con2 contact; the 3rd pin of the chip N10 is respectively connected to one end of the capacitor C112 and the V+ contact, the 1st pin of the chip N10 is respectively connected to the other end of the resistor R17 and the 3rd pin of the chip N13, the 2nd pin of the chip N13 is grounded, the 1st pin of the chip N13 is connected to one end of the resistor R13, the other end of the resistor R23 is connected to the SW contact, and the V+ contact is connected to the load.

[0084] like Figure 15 The Bluetooth power supply circuit of this embodiment is shown, which is used to power the receiving Bluetooth communication circuit. The Bluetooth power supply circuit includes chip N14 (H7226-1), capacitors C114-116, chip N14, diode Z3, and resistor R30. Pin 3 of chip N14 is connected to grounded capacitor C116 and the 3.3V terminal, while pin 1 of chip N14 is connected to ground. Pin 2 of chip N14 is connected to grounded capacitor C114-115, the cathode of diode Z3, and one end of resistor R30, respectively. The other end of resistor R30 is connected to the VIN terminal, and the anode of diode Z3 is grounded.

[0085] like Figure 16 As shown, in this embodiment, an output voltage sampling circuit is provided. The output voltage sampling circuit includes a resistor R18, a resistor R22, a diode Z2, and a capacitor C109. One end of the resistor R18 is connected to the V+ connection point, and the other end thereof is connected to a grounded resistor R24, the cathode of the diode Z2, the grounded capacitor C109, and one end of the resistor R22. The anode of the diode Z2 is grounded, and the other end of the resistor R22 is connected to the Vs2 connection point.

[0086] like Figure 17 As shown, the receiving Bluetooth communication circuit includes a chip U2 (MFRC52202HN1,151), capacitors C117-123, capacitors 129-130, capacitor C135, capacitor C141, a magnetic bead FB2, a chip Y2 and a terminal P1 (PZ254V-11-04P); the 5th pin of the chip U2 is respectively connected to its 18th pin, the grounded capacitors C120-123, the 3V3 contact and one end of the magnetic bead FB2, its 6th and 25th pins are grounded, its 7-8th pins are respectively connected to the grounded capacitor C129 and the grounded capacitor C130, its 4th, 10th, 1st and 12th pins are respectively connected to the SW contact, the IF contact, the SWS contact and the Vs2 contact, its 19th pin is connected to one end of the capacitor C117, and its 1st pin is connected to the SW contact, the IF contact, the SWS contact and the Vs2 contact. Pin 6 is connected to pin 1 of chip Y2 and ground capacitor C135 respectively, and pin 17 is connected to chip Y2 and ground capacitor C141 respectively; pins 2 and 4 of chip Y2 are grounded; the other end of ferrite bead FB2 is connected to ground capacitor C119 and 3.3V contact respectively, the other end of capacitor C117 is connected to one end of inductor L17 and ground capacitor C125 in proportion, the other end of inductor L17 is connected to one end of inductor L18 and ground capacitor C126 respectively, the other end of inductor L18 is connected to ground capacitor C127 and one end of capacitor C118 respectively, the other end of capacitor C118 is connected to Bluetooth antenna ANT2 and grounded; pins 1-3 of terminal P1 are connected to 3V3 contact, SWS contact and AGND contact respectively.

[0087] The present invention improves the problem that the input impedance and coupling strength of the transmitting antenna vary greatly under different coupling distances, and do not match the output impedance of the power amplifier output, which leads to large reflection at the power amplifier end and thus low efficiency, and at the same time increases the stray radiation in space. Under different coupling conditions, due to the different coupling coefficients and coupling strengths between the transmitting antenna and the receiving antenna, the input impedance of the transmitting antenna at the transmitting end varies greatly at different distances, while the output impedance of the power amplifier varies very little within a certain power range, resulting in a serious mismatch between the input impedance of the transmitting antenna and the output impedance of the power amplifier at some coupling distances, which aggravates the spatial stray. The present invention matches the input impedance of the antenna to the output impedance variation range of the power amplifier through impedance matching based on the different input impedances of the antenna at different coupling distances, thereby improving the overall efficiency and improving the spatial stray.

[0088] Example 2

[0089] The impedance change of the antenna system after the primary mapping circuit A1 and the secondary mapping circuit B1 when the transmitting and receiving antennas are within the distance range of 0cm-5cm.

[0090] according to Figure 18 The schematic diagram shown in the figure adopts the following electrical parameters for this case in combination with actual application requirements:

[0091] Table 1: Electrical parameters for implementation case 2 with only the capacitor matching network

[0092] Symbols Value C149 58pF C147 150pF C153 150pF

[0093] Table 2: Zin values ​​measured under the electrical parameters in Table 1

[0094] distance frequency Zin 0cm 6.78Mhz 79R-23j 1cm 6.78Mhz 54R-17j 2cm 6.78Mhz 43R-10j 3cm 6.78Mhz 29R-0j 4cm 6.78Mhz 22R+3j 5cm 6.78Mhz 16R+6j

[0095] according to Figure 19 In the schematic diagram shown, ZL is the equivalent impedance of the receiving end, and Zin is the input impedance of the transmitting antenna. The following electrical parameters are used for this case based on actual application requirements:

[0096] Table 3: Electrical parameters when adding the primary mapping circuit in implementation case 2

[0097] Symbols Value Symbols Value C156 58pF L24 477nH C158 150pF C157 330pF C155 150pF

[0098] Table 4: Zin values ​​measured under the electrical parameters in Table 3

[0099] distance frequency Zin distance frequency Zin 0cm 6.78Mhz 30R-34j 3cm 6.78Mhz 37R-0j 1cm 6.78Mhz 32R-25j 4cm 6.78Mhz 35R+13j 2cm 6.78Mhz 34.5R-15j 5cm 6.78Mhz 32R+25j

[0100] according to Figure 20 In the schematic diagram shown, ZL is the equivalent impedance of the receiving end, and Zin is the input impedance of the transmitting antenna. The following electrical parameters are used for this case based on actual application requirements:

[0101] Table 5: Electrical parameters when primary and secondary mapping circuits are added in Implementation Case 2

[0102] Symbols Value Symbols Value C183 58pF C185 330pF C186 150pF L36 500nH C182 150pF C184 200pF L37 477nH

[0103] Table 6: Zin values ​​measured under the electrical parameters in Table 5

[0104] distance frequency Zin 0cm 6.78Mhz 36R-20j 1cm 6.78Mhz 35R-15j 2cm 6.78Mhz 33R-12j 3cm 6.78Mhz 34R-0j 4cm 6.78Mhz 34.5R+6j 5cm 6.78Mhz 35R+17j

[0105] Example 3: Combining the primary mapping circuit, secondary mapping circuit and capacitor matching network of Example 2, the receiving end adopts only a capacitor matching circuit, adds a hybrid filter, adds a primary filter and a hybrid filter respectively.

[0106] according to Figure 21 In the schematic diagram shown, Zin is the antenna input impedance at the transmitting end, and ZL is the equivalent load impedance at the receiving end. The following electrical parameters are used for this case based on actual application requirements:

[0107] Table 7: Electrical parameters of the transmitter with the primary and secondary mapping circuits added, and the receiver with only the capacitor matching network.

[0108]

[0109]

[0110] When the transmitter adds the primary mapping circuit and the secondary mapping circuit, and the receiver only has the capacitor matching network, the spurious emission in the frequency range of 100KHz-300MHz is more serious. The spurious emission in the frequency range of 100KHz-150MHz is more serious than that in the frequency range of 150MHz-300MHz. Figure 24 For the test results.

[0111] according to Figure 22 In the schematic diagram shown, Zin is the input impedance of the transmitting antenna, and ZL is the DC load. Based on the actual application requirements, the following electrical parameters are used in this case:

[0112] Table 8: Electrical parameters of the transmitter with the primary and secondary mapping circuits and the receiver with the capacitor matching network and hybrid filter.

[0113] Symbols Value Symbols Value C165 58pF C163 100pF C162 150pF C171 100pF C170 150pF C164 170pF L26 477nH C169 170pF C167 330pF L27 600nH L25 500nH L29 600nH C166 200pF L28 440nH C168 68pF

[0114] When the primary and secondary mapping circuits are added to the transmitter and the capacitor matching network and hybrid filter are added to the receiver, the spurious signals in the frequency range of 100KHz-300MHz are significantly improved compared to the case where the primary and secondary mapping circuits are added to the transmitter and only the capacitor matching network is used at the receiver. Among them, the spurious signals in the frequency band of 100KHz-20.34MHz are improved very little, and the spurious signals in the frequency band of about 20.34MHz-100MHz are also improved very little, and can only be suppressed to below -65dBm; the spurious signals in the frequency band of 100MHz-300MHz are improved very significantly, and all spurious signals are below -77dBm, indicating that the hybrid filter has a weak effect on the spurious signal suppression in the frequency band of 100KHz-100MHz, but a more obvious effect on the spurious signal suppression in the frequency band of 100MHz-300MHz. Figure 25 For the test results.

[0115] according to Figure 23 In the schematic diagram shown, Zin is the input impedance of the transmitting antenna, and ZL is the DC load. Based on the actual application requirements, the following electrical parameters are used in this case:

[0116] Table 9: Electrical parameters of the transmitter with the primary and secondary mapping circuits, and the receiver with the capacitor matching network, hybrid filter, and primary filter.

[0117]

[0118]

[0119] When the transmitter adds the primary mapping circuit and the secondary mapping circuit, and the receiver has the capacitor matching network, the hybrid filter, and the primary filter, compared with the case where the transmitter adds the primary mapping circuit and the secondary mapping circuit, and the receiver has the capacitor matching network and the hybrid filter, the spurious signal in the 100KHz-20.34MHz band is not significantly improved, while the spurious signal in the 20.34MHz-100MHz band is significantly improved, both suppressed below -80dBm. The spurious signal in the 100MHz-300MHz band deteriorates to a certain extent, but is also suppressed below -75dBm. This shows that the primary filter has only a small inhibitory effect on the spurious signal in the 100KHz-20.34MHz band, and has a good inhibitory effect on the spurious signal in the 20.34MHz-100MHz band, but has a worsening effect on the spurious signal in the 100MHz-300MHz band. Figure 26 For the test results.

Claims

1. A magnetic resonance wireless charging system that suppresses system radiation and stray radiation, characterized in that: It includes an adapter, a magnetic resonance transmitting module and a magnetic resonance receiving module; The magnetic resonance transmission module includes a DC / DC power supply, a radio frequency power amplifier circuit, a radio frequency filtering circuit, a plurality of secondary mapping circuits, a plurality of primary mapping circuits, a transmitting Bluetooth communication circuit and a transmitting antenna. Each group of primary mapping circuits is composed of an LC matching and a capacitor matching network, and each group of secondary mapping circuits is composed of an LC matching network. The DC / DC power supply is electrically connected to the adapter, the radio frequency power amplifier circuit and the transmitting Bluetooth communication circuit respectively. The radio frequency power amplifier circuit is electrically connected to the radio frequency filtering circuit. The radio frequency filtering circuit is electrically connected to each group of secondary mapping circuits respectively. Each group of secondary mapping circuits is electrically connected to each other and to each group of primary mapping circuits respectively. Each group of primary mapping circuits is electrically connected to the transmitting antenna respectively. The input and output ends of the primary mapping circuit are both provided with switches, and the input end of the secondary mapping circuit is provided with a switch. The magnetic resonance receiving module includes a receiving antenna, a common mode filter 1, a receiving capacitor matching circuit, a radio frequency filtering circuit, a common mode filter 2, a rectifier and voltage stabilization circuit, and a load, which are electrically connected in sequence. It also includes a receiving Bluetooth communication circuit, the receiving antenna is communicatively connected to the transmitting antenna, the receiving Bluetooth communication circuit is communicatively connected to the transmitting Bluetooth communication circuit, and the receiving Bluetooth communication circuit is electrically connected to the rectifier and voltage stabilization circuit; If the antenna impedance variation is within the system’s set threshold, a set of primary mapping circuits is used to match the input impedance of the power amplifier with the input impedance of the transmitting antenna; If the antenna impedance variation exceeds a system-set threshold, multiple sets of primary mapping circuits or a combination of primary and secondary mapping circuits are used to match the input impedance of the power amplifier with the input impedance of the transmitting antenna; If the distance between the receiving antenna and the transmitting antenna changes beyond a system-set threshold, multiple sets of primary mapping circuits and multiple sets of secondary mapping circuits are used to match the input impedance of the power amplifier with the input impedance of the transmitting antenna.

2. The magnetic resonance wireless charging system for suppressing system radiation and stray radiation according to claim 1, characterized in that: The common-mode filter 1 and common-mode filter 2 are respectively the primary filter and the secondary hybrid filter of the magnetic resonance receiving module; the cutoff frequency of the primary filter is greater than 6.78 MHz, and is used to filter out-of-band high-frequency harmonics and stray signals received by the receiving antenna; the secondary hybrid filter is used to filter out high-frequency harmonics and stray signals caused by the nonlinearity and switching characteristics deterioration of the rectifier diode in the receiving capacitor matching circuit.

3. The magnetic resonance wireless charging system for suppressing system radiation and stray radiation according to claim 2, characterized in that: The common-mode filter 1 and the common-mode filter 2 may both be a combination of multiple common-mode filters.

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