Magnetic resonance wireless power supply system and method for implantable medical device

Abstract

The application relates to a magnetic resonance wireless power supply system and method for an implantable medical device, wireless electric energy is transmitted by resonance achieved at a transmitting end and a receiving end through coupling between a transmitting coil and a receiving coil. The transmitting coil and the receiving coil both adopt a working frequency of 6.78 MHz to form resonance, so that the conversion of the alternating magnetic field is strengthened, the transmission efficiency is relatively high, a relatively long transmission distance can be achieved, the maximum transmission distance is not less than 3 cm, radiation is small during the transmission process, therefore, the resonance frequency cannot cause an eddy current effect of a metal product, the metal shell cannot be heated, so that the system can be applied to the implantable medical field and is used for wireless power supply of the implantable medical device.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a magnetic resonance wireless power supply system and method for implantable medical devices. Background Technology

[0002] Implantable medical devices play an increasingly important role in modern medical treatment, and are widely used in the treatment of various diseases, including neurological disorders, cardiovascular diseases, and chronic pain. Typical implantable medical devices include deep brain stimulators (DBS), spinal cord stimulators (SCS), pacemakers, cochlear implants, and drug infusion pumps. These devices typically require a continuous and stable power supply to function properly; therefore, power supply technology is one of the key issues in the design of implantable medical devices.

[0003] In traditional technology, the power supply methods for implantable medical devices are mainly divided into two categories: battery power and percutaneous wired power. Battery power involves embedding a rechargeable or non-rechargeable battery within the implanted device. Its disadvantages include limited battery life, requiring periodic surgical replacements, which not only increases the patient's financial burden and surgical risks but may also increase the risk of infection at the implantation site due to frequent surgeries. Percutaneous wired power connects an external power source to the implanted device via a wire penetrating the skin. While this provides continuous power, the location where the wire passes through the skin can easily become a channel for bacterial invasion, significantly increasing the risk of infection. Furthermore, the wire restricts the patient's daily activities, impacting their quality of life.

[0004] In recent years, wireless power supply technology has gradually attracted attention in the field of implantable medical devices due to its advantages such as eliminating the need for physical connections, reducing the risk of infection, and increasing patients' freedom of movement. Traditional wireless power supply technology mainly uses magnetic induction coupling technology, represented by the Qi standard, which typically uses 100kHz~300kHz as the resonant frequency and achieves energy transfer through magnetic field coupling between the transmitting coil and the receiving coil.

[0005] However, traditional magnetic induction wireless power supply technology suffers from drawbacks in implantable medical applications, such as insufficient transmission distance (usually no more than 1 cm) and low transmission efficiency (usually no more than 20%). Furthermore, the resonant frequency causes eddy currents in the metal, generating heat and causing the metal casing to overheat. These shortcomings severely limit the application of this technology in implantable medical fields. Summary of the Invention

[0006] Therefore, it is necessary to provide a magnetic resonance wireless power supply system and method for implantable medical devices to address the aforementioned technical problems.

[0007] In a first aspect, this application provides a magnetic resonance wireless power supply system for implantable medical devices, the system comprising an implantable receiver and an external transmitter. The external transmitter includes a first main control module and an adjustable power supply module, a first voltage and current sampling module, a power amplifier and drive module, and a transmitting coil connected in sequence. The first main control module is connected to the adjustable power supply module and the first voltage and current sampling module respectively. The first main control module is used to generate control signals based on the feedback signals from the implanted receiver. The adjustable power supply module is used to adjust the output voltage according to the control signal; The first voltage and current sampling module is used to collect the voltage and current output by the adjustable power supply module; The power amplifier and drive module is used to convert the input DC power supply into an alternating sinusoidal AC power supply with a frequency of 6.78MHz, and drive the transmitting coil to transmit energy; The implanted receiver includes a second main control module and a receiving coil, a rectification and filtering module, a voltage sampling module, a DC power conversion module, a second voltage and current sampling module, and a DC output module connected in sequence. The second main control module is connected to the voltage sampling module and the second voltage and current sampling module respectively, and is used to control the sampling timing. The receiving coil is used to receive the 6.78MHz alternating magnetic field energy emitted by the transmitting coil; The rectifier and filter module is used to convert the received AC power into DC power and filter out high-frequency noise; The voltage sampling module is used to sample the rectified and filtered voltage under the control of the second main control module; The DC power conversion module is used to perform secondary conversion on the rectified and filtered voltage to obtain a constant voltage and output it. The second voltage and current sampling module is used to sample the voltage and load current output by the DC power conversion module under the control of the second main control module; The DC output module is used to supply power to the implantable medical device.

[0008] In one embodiment, the external transmitter further includes a protection module connected to the input of the adjustable power module for supplying a protective DC power supply to the adjustable power module.

[0009] In one embodiment, the external transmitter further includes a first temperature acquisition module, which is used to acquire a first temperature signal from at least one of the following locations: the circuit board, functional module, transmitting coil, and housing surface of the external transmitter, and send the first temperature signal to the first main control module.

[0010] In one embodiment, the implantable receiver further includes a second temperature acquisition module, which is used to acquire a second temperature signal from at least one of the following locations: the board, the functional module, the receiving coil, and the surface of the housing of the implantable receiver, and to send the second temperature signal to the second main control module.

[0011] In one embodiment, the receiving coil includes a ceramic substrate and a metal circuit layer disposed on the ceramic substrate; the metal circuit layer includes a conductive layer and a biocompatible metal layer, wherein the biocompatible metal layer completely encapsulates the conductive layer.

[0012] In one embodiment, the ceramic substrate is made of at least one of alumina, aluminum nitride, zirconium oxide, silicon carbide, or silicon nitride.

[0013] In one embodiment, the ceramic substrate has a thickness of 0.2 mm.

[0014] In one embodiment, the metal circuit layer is composed of multiple racetrack-shaped metal wires, the wires having a width of 0.1~0.3mm, a spacing of 0.2~0.4mm, and a thickness of 0.05~0.2mm.

[0015] In one embodiment, the conductive layer is made of copper.

[0016] In one embodiment, the biocompatible metal layer is selected from at least one of titanium, tungsten, platinum, gold and niobium; the thickness of the biocompatible metal layer is 0.01~0.1 mm.

[0017] Secondly, this application also provides a magnetic resonance wireless power supply method, applied to the system described above, the method comprising: Step S1: The external transmitter responds to the initial driving voltage and initiates wireless power transmission; Step S2: The implanted receiver samples the rectified and filtered voltage and feeds it back to the external transmitter. Step S3: If the external transmitter determines that the voltage fed back by the implantable receiver is within the preset tolerance, then the transmitter voltage is adjusted and the process returns to step S2 until the preset number of adjustments is reached and the preset tolerance is met. Then, the handshake is determined to be successful and step S4 is executed. Step S4: The external transmitter calculates the power supply efficiency. If the power supply efficiency is lower than a preset value, it prompts the user to adjust the position. Step S5: After the power supply efficiency reaches a preset value, the system enters a normal operating mode. In the normal operating mode, the external transmitter dynamically adjusts the transmission power according to the voltage feedback from the implanted receiver to make the voltage after rectification and filtering by the implanted receiver relatively stable.

[0018] In one embodiment, the method further includes: if the external transmitter determines that the voltage fed back by the implantable receiver is not within a preset tolerance, then the power supply is stopped and an alarm is issued.

[0019] In one embodiment, the method further includes: in the normal operating mode, if the external transmitter determines that the first temperature signal is abnormal, then anomaly handling and reporting are initiated.

[0020] The aforementioned magnetic resonance wireless power supply system and method for implantable medical devices transmits wireless power by achieving resonance at the transmitting and receiving ends through coupling between the transmitting and receiving coils. Both the transmitting and receiving coils operate at a frequency of 6.78MHz to form resonance, thereby enhancing the energy conversion of the alternating magnetic field, resulting in high transmission efficiency and a long transmission distance (maximum of at least 3cm). Radiation during transmission is minimal; therefore, the resonant frequency does not induce eddy currents in metal products or heat the metal casing, making it suitable for use in implantable medical devices for wireless power supply. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a structural block diagram of a magnetic resonance wireless power supply system for an implantable medical device in one embodiment.

[0023] Figure 2 This is a schematic diagram of the receiving coil in one embodiment.

[0024] Figure 3 This is a schematic diagram of the layer structure of the receiving coil in one embodiment.

[0025] Figure 4 This is a flowchart illustrating a magnetic resonance wireless power supply method in one embodiment. Detailed Implementation

[0026] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0027] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0028] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0029] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0030] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0031] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0032] In one exemplary embodiment, a magnetic resonance wireless power supply system for implantable medical devices is provided, such as... Figure 1 As shown, the system includes an external transmitter 100 and an implantable receiver 200.

[0033] The external transmitter 100 is located externally and includes a first main control module (i.e., transmitter main control) and an adjustable power supply module, a first voltage and current sampling module (i.e., voltage and current sampling), a power amplifier and drive module, and a transmitting coil connected in sequence. The first main control module is connected to the adjustable power supply module and the first voltage and current sampling module respectively.

[0034] The implantable receiver 200 is implanted in the body and includes a second main control module (i.e. receiver main control) and a receiving coil, a rectification and filtering module, a voltage sampling module, a DC power conversion module, a second voltage and current sampling module (i.e. voltage and current sampling) and a DC output module connected in sequence. The second main control module is connected to the voltage sampling module and the second voltage and current sampling module (i.e. voltage and current sampling) respectively.

[0035] In this embodiment, for the external transmitter 100, the first main control module serves as the control core of the transmitter. It receives feedback signals such as voltage and current from the receiver via bidirectional communication and, combined with locally sampled voltage and current data, runs a control algorithm (such as PID control) to generate a control signal. This control signal is used to dynamically adjust the output voltage of the adjustable power supply module, thereby changing the transmission power. The adjustable power supply module, controlled by the first main control module, can linearly or incrementally adjust its output voltage according to the control signal, thus providing a variable DC bus voltage for the subsequent power amplification. The first voltage and current sampling module is used to collect the voltage and current output by the adjustable power supply module in real time and convert the analog signals into digital signals, sending them to the first main control module as feedback for closed-loop control. The power amplification and drive module can adopt a full-bridge or half-bridge inverter circuit topology to convert the input DC power supply into an alternating sinusoidal AC power supply with a frequency of 6.78MHz, and drive the transmitting coil to generate a high-frequency alternating magnetic field to transmit energy.

[0036] For the implantable receiver 200, the receiving coil receives the 6.78MHz alternating magnetic field energy emitted by the transmitting coil; the rectification and filtering module uses a synchronous rectification or Schottky diode rectification circuit to convert the high-frequency AC voltage of the 6.78MHz alternating magnetic field energy induced by the receiving coil into DC voltage, and filters out high-frequency noise through an LC filter network to obtain a smooth DC voltage; the voltage sampling module samples the rectified and filtered voltage in real time under the control of the second main control module; the DC power conversion module can use a DC-DC converter (such as Buck or LDO) to perform a secondary conversion on the rectified and filtered voltage to obtain a constant voltage for output, such as the constant voltage required by implantable medical devices such as pacemakers, nerve stimulators, etc. (e.g., 3.3V or 5.0V); the second voltage and current sampling module samples the final voltage and load current output by the DC power conversion module under the control of the second main control module; the DC output module supplies power to the implantable medical device; the second main control module is responsible for coordinating the operation of each module of the receiver, controlling the sampling timing, and reporting the local voltage, current, and other statuses to the transmitting end through bidirectional communication.

[0037] In the aforementioned magnetic resonance wireless power supply system for implantable medical devices, wireless power is transmitted through resonance achieved at the transmitting and receiving ends via coupling between the transmitting and receiving coils. Both the transmitting and receiving coils operate at a frequency of 6.78MHz to create resonance, thus avoiding common Qi standards (100-300kHz) and reducing interference with other wireless charging devices. Furthermore, this frequency exhibits good penetration characteristics in biological tissues, enhancing the energy conversion of the alternating magnetic field and resulting in high transmission efficiency and a long transmission distance (maximum of at least 3cm) with minimal radiation during transmission. Moreover, its resonant frequency does not induce eddy currents in metal products and does not heat the metal casing, making it suitable for use in implantable medical devices for wireless power supply.

[0038] In an exemplary embodiment, the aforementioned DC output module may further include overvoltage, overcurrent, and overheat protection circuits to provide necessary protection for the DC power supply to be output, thereby ensuring that the output power supply is safe and reliable. Furthermore, the output switch is only closed to supply power to the load, such as an implantable medical device, when the system confirms that it is working normally; if an abnormality is detected, the output is immediately cut off to protect the tissue inside the body.

[0039] In one exemplary embodiment, the external transmitter may further include a protection module connected to the input of the adjustable power module for supplying a protective DC power supply to the adjustable power module. Specifically, the protection module has surge protection, hot-swap protection, reverse connection protection, overvoltage and overcurrent protection functions, thereby ensuring a stable and reliable power input to the subsequent circuits.

[0040] In an exemplary embodiment, the external transmitter may further include a first temperature acquisition module (i.e., temperature acquisition), which can be implemented using a temperature sensor (such as an NTC thermistor). This module acquires a first temperature signal from at least one location among the external transmitter's circuit board, functional modules, transmitting coil, and casing surface, and sends the acquired first temperature signal to the first main control module. The first main control module then dynamically adjusts the output voltage of the adjustable power supply module based on the first temperature signal and locally sampled voltage and current data, thereby changing the transmission power. By monitoring the temperature in real time, it prevents overheating and burns to the user and also prevents overheating damage to components.

[0041] In one exemplary embodiment, the transmitting coil may consist of a coil wound with multiple strands of Litz wire, a magnetic shielding sheet (such as ferrite or nanocrystalline material), a dielectric layer, and a support. The magnetic shielding sheet is used to guide the direction of magnetic field lines, reducing radiation loss towards the back of the human body; the dielectric layer is used for electrical isolation.

[0042] In one exemplary embodiment, the implantable receiver may further include a second temperature acquisition module, which can be implemented using a temperature sensor (such as an NTC thermistor). This module acquires a second temperature signal from at least one location among the implantable receiver's circuit board, functional module, receiving coil, and casing surface, and sends this second temperature signal to a second main control module. The second main control module also feeds back the second temperature signal to the transmitter, enabling the transmitter to dynamically adjust the output voltage of the adjustable power module based on the second temperature signal and locally sampled voltage and current data, thereby changing the transmission power. This real-time temperature monitoring prevents overheating and burns to the user, and also prevents overheating damage to components.

[0043] In one exemplary embodiment, such as Figure 2 As shown, the receiving coil may include a ceramic substrate 21 and a metal circuit layer 22 disposed on the ceramic substrate 21. Since the receiving coil is implanted in the body and has strict requirements for temperature rise, the ceramic substrate 21 can be made of at least one of alumina, aluminum nitride, zirconium oxide, silicon carbide, or silicon nitride. It possesses high hardness, high insulation, and good thermal conductivity, effectively protecting the circuit layer and adapting to the complex physiological environment within the body. The metal circuit layer 22 is composed of a single metal or two or more metals, including but not limited to copper, titanium, tungsten, platinum, gold, and niobium. Through a 6.78MHz frequency and optimized coil design, compared to low-frequency, high-current solutions, it significantly reduces the eddy current effect of metal components in an alternating magnetic field, thereby reducing heat generation and preventing high-temperature damage to surrounding sensitive human tissues.

[0044] In one scenario, the thickness of the ceramic substrate 21 is 0.2 mm. For example... Figure 3 As shown, the metal circuit layer 22 can be composed of multiple racetrack-shaped metal wires with a wire width of 0.1~0.3mm, a wire spacing of 0.2~0.4mm, and a thickness of 0.05~0.2mm.

[0045] For example, such as Figure 3 As shown, the metal circuit layer 22 may include a conductive layer 221 and a biocompatible metal layer 222, and the biocompatible metal layer 222 completely covers the conductive layer 221.

[0046] In one scenario, the biocompatible metal layer may be selected from at least one of titanium, tungsten, platinum, gold and niobium; the thickness of the biocompatible metal layer is 0.01~0.1 mm.

[0047] In one scenario, the conductive layer can be made of copper. The inner copper layer ensures low resistance and high conductivity, while the outer biocompatible metal (titanium, platinum, etc.) completely isolates the copper from contact with human body fluids, preventing toxic reactions and corrosion caused by copper ion precipitation, thus meeting the long-term biocompatibility requirements of implantable medical devices.

[0048] In one exemplary embodiment, based on such Figure 2 , Figure 3 The receiving coil shown is assembled with a hand-wound transmitting coil as follows: Figure 1 The wireless power supply system shown was prepared according to the formulation in Appendix L of AAMIISO TIR10974-2018, using gels (high dielectric constant medium (HPM) polyacrylic acid gel (PAA)) with thicknesses of 1 cm, 2 cm, and 3 cm to simulate biological tissue. The transmission efficiency was tested at the three thicknesses, and the test results are shown in Table 1 below. Table 1 is as follows: As shown in Table 1 above, even with a gel thickness of 3 cm, the power supply efficiency can still reach over 29%, which is higher than the efficiency of traditional magnetic induction power supply (20%). This demonstrates that it reduces energy loss during transmission and lowers the overall power consumption of the system.

[0049] In one exemplary embodiment, based on the same inventive concept, this application also provides a magnetic resonance wireless power supply method. This method can be applied to, for example... Figure 1 The system shown employs a hardware and software coordination approach to prevent unauthorized device access or co-channel interference, ensuring that only legitimate transmitters and receivers can establish an energy transmission link, thereby providing safe power to implantable medical devices. For example... Figure 4 As shown, the method may include the following steps: Step S1: The external transmitter responds to the initial driving voltage and initiates wireless power transmission.

[0050] The initial drive voltage can be a voltage set by the external transmitter during the initial wearing phase to ensure that the wireless power supply reception of the receiver can be activated. Specifically, the external transmitter responds to this initial drive voltage and initiates wireless power transmission. For example, the first main control module of the external transmitter can control the adjustable power module to output a lower initial drive voltage (e.g., 5V) to initiate 6.78MHz power transmission. At this time, the DC output module of the receiver is in the off state by default.

[0051] Step S2: The implanted receiver samples the rectified and filtered voltage and feeds it back to the external transmitter.

[0052] Specifically, upon power-on reset of the implanted receiver, its second main control module is activated, which then controls the voltage sampling module to acquire the rectified and filtered voltage value. And it is fed back to the external transmitter.

[0053] Step S3: If the external transmitter determines that the voltage fed back by the implanted receiver is within the preset tolerance, then adjust the transmission voltage and return to step S2 until the preset number of adjustments is reached and the preset tolerance is met, then the handshake is determined to be successful and step S4 is executed.

[0054] After receiving the data, the external transmitter determines... Is it within the preset target tolerance range (e.g., target value ±10%)? If it is within the preset tolerance range, adjust the transmit voltage and return to step S2 until the preset number of adjustments is reached and the preset tolerance is met. Then, the handshake is considered successful and step S4 is executed.

[0055] For example, taking a preset number of handshakes of 3, if the first handshake requires setting the receiver voltage to A and the transmitter adjusting its transmission power, and if the receiver voltage is adjusted to a preset range (e.g., A ± 10%) within 50ms, the first handshake is considered successful, and the second handshake is then performed. If the second handshake requires setting the receiver voltage to B and the transmitter adjusting its transmission power, and if the receiver voltage is adjusted to a preset range (e.g., B ± 10%) within 50ms, the second handshake is considered successful, and the third handshake is then performed. If the third handshake requires setting the receiver voltage to C and the transmitter adjusting its transmission power, and if the receiver voltage is adjusted to a preset range (e.g., C ± 10%) within 50ms, the third handshake is considered successful. If all three handshakes are successful, step S4 is executed; if any handshake fails, the handshake fails.

[0056] Understandably, the aforementioned "inquiry-adjustment-feedback" cycle needs to be successfully executed a preset number of times (e.g., 3 times, this number is configurable). If the voltage remains stable within the tolerance within the preset number of times, the handshake is considered successful, both parties establish a legitimate energy transmission link, and enter the subsequent position correction mode.

[0057] In one scenario, if any handshake fails, such as when the external transmitter determines that the voltage fed back by the implanted receiver is outside the preset tolerance, power supply will be stopped and an alarm will be issued. For example, the first main control module of the transmitter will immediately stop transmitting and prompt the user to check the device via an audible and visual alarm.

[0058] Only devices that pass the above multiple handshake verifications can establish an energy link, thereby effectively preventing unauthorized third-party devices from mistakenly receiving energy and causing overheating, and also preventing the transmitter from emitting high-power energy to non-target objects (such as coins, keys, and other metallic foreign objects), thus avoiding energy waste.

[0059] Step S4: The external transmitter calculates the power supply efficiency. If the power supply efficiency is lower than the preset value, it prompts the user to adjust the position.

[0060] After a successful handshake, the system does not immediately supply power but instead enters the position optimization phase. During this phase, the transmitter continuously acquires voltage and current data from the receiver and calculates the power supply efficiency based on the transmitter's input power. If the power supply efficiency is lower than a preset value (e.g., 20%), it indicates poor coil alignment or a significant obstacle, prompting the system to adjust its position. This may be indicated via voice or display prompts such as "Please adjust the transmitter position" or "Please remove the obstruction." The system enters normal operation mode (step S5) once the power supply efficiency is greater than or equal to the preset value.

[0061] Step S5: Once the power supply efficiency reaches the preset value, the system will enter normal operating mode.

[0062] In normal operating mode, the external transmitter can dynamically adjust the transmission power based on the voltage feedback from the implanted receiver to ensure that the voltage after rectification and filtering by the implanted receiver is relatively stable.

[0063] For example, in normal operating mode, when the power supply is turned on, if the second main control module at the receiving end confirms that the voltage and current sampling values ​​are normal and the temperature is not abnormal, it can control the DC output module to close so as to output a stable DC power supply to the implantable medical device.

[0064] During operation, slight shifts in the relative position of the coils due to patient movement or changes in the load of the implantable medical device can cause fluctuations in the rectified voltage at the receiving end. Therefore, the receiving end samples the data in real time and reports it. The first main control module at the transmitting end dynamically fine-tunes the output voltage of the adjustable power module based on the feedback data, thereby changing the transmission power to keep the rectified voltage at the receiving end constant, ensuring that the downstream DC-DC converter operates at its optimal efficiency point. For example, when the position shift is small (such as forward, backward, left, right, or up and down), the receiving end voltage will decrease. After receiving the feedback voltage from the receiving end, the transmitting end can increase the transmission power to restore the receiving end voltage to a relatively stable value. If the position shift is too large, the transmitting end will initially increase the transmission power to try to restore the receiving end voltage to a relatively stable value, but at this time, the current at the transmitting end will also increase sharply, leading to decreased efficiency and increased temperature. If the position shifts from the offset position to a point where the horizontal and vertical distances are close, the receiving end voltage will rise. After receiving the feedback voltage from the receiving end, the transmitting end can decrease the transmission power to restore the receiving end voltage to a relatively stable value.

[0065] In one scenario, the temperature acquisition modules at both the transmitting and receiving ends can monitor the temperature in real time. If the temperature at either end exceeds a safety threshold (e.g., greater than 41°C), the corresponding main control module will immediately reduce power or cut off the output and generate an alarm message, thereby achieving over-temperature protection.

[0066] In one scenario, if the transmitter does not receive a feedback signal from the receiver for several consecutive cycles (which may mean that the receiver has been removed or communication has failed), the transmitter can stop transmitting energy to achieve communication loss protection and prevent no-load heating or heating of surrounding metal objects.

[0067] In one scenario, if the voltage sampled by the transmitter or receiver exceeds the safe range (e.g., above 20V), the system can also enter a fault protection state, such as cutting off the output and recording a fault code, thereby minimizing potential safety risks and ensuring high reliability of the system in complex electromagnetic environments and patients' daily activities.

[0068] It should be understood that although the steps in the flowcharts of the embodiments described above are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the embodiments described above may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.

[0069] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0070] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0071] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A magnetic resonance wireless power supply system for implantable medical devices, characterized in that, The system includes an implantable receiver and an external transmitter. The external transmitter includes a first main control module and an adjustable power supply module, a first voltage and current sampling module, a power amplifier and drive module, and a transmitting coil connected in sequence. The first main control module is connected to the adjustable power supply module and the first voltage and current sampling module respectively. The first main control module is used to generate control signals based on the feedback signals from the implanted receiver. The adjustable power supply module is used to adjust the output voltage according to the control signal; The first voltage and current sampling module is used to collect the voltage and current output by the adjustable power supply module; The power amplifier and drive module is used to convert the input DC power supply into an alternating sinusoidal AC power supply with a frequency of 6.78MHz, and drive the transmitting coil to transmit energy; The implanted receiver includes a second main control module and a receiving coil, a rectification and filtering module, a voltage sampling module, a DC power conversion module, a second voltage and current sampling module, and a DC output module connected in sequence. The second main control module is connected to the voltage sampling module and the second voltage and current sampling module respectively, and is used to control the sampling timing. The receiving coil is used to receive the 6.78MHz alternating magnetic field energy emitted by the transmitting coil; The rectifier and filter module is used to convert the received AC power into DC power and filter out high-frequency noise; The voltage sampling module is used to sample the rectified and filtered voltage under the control of the second main control module; The DC power conversion module is used to perform secondary conversion on the rectified and filtered voltage to obtain a constant voltage and output it. The second voltage and current sampling module is used to sample the voltage and load current output by the DC power conversion module under the control of the second main control module; The DC output module is used to supply power to the implantable medical device.

2. The system according to claim 1, characterized in that, The external transmitter also includes a protection module, which is connected to the input terminal of the adjustable power module and is used to input a DC power supply for protection to the adjustable power module.

3. The system according to claim 1, characterized in that, The external transmitter also includes a first temperature acquisition module, which is used to acquire a first temperature signal from at least one of the following locations: the circuit board, functional module, transmitting coil, and casing surface of the external transmitter, and send the first temperature signal to the first main control module.

4. The system according to claim 1, characterized in that, The implanted receiver also includes a second temperature acquisition module, which is used to acquire a second temperature signal from at least one location among the board, functional module, receiving coil and housing surface of the implanted receiver, and send the second temperature signal to the second main control module.

5. The system according to any one of claims 1 to 4, characterized in that, The receiving coil includes a ceramic substrate and a metal circuit layer disposed on the ceramic substrate; the metal circuit layer includes a conductive layer and a biocompatible metal layer, wherein the biocompatible metal layer completely encapsulates the conductive layer. The ceramic substrate is made of at least one of alumina, aluminum nitride, zirconium oxide, silicon carbide, or silicon nitride; the thickness of the ceramic substrate is 0.2 mm. The conductive layer is made of copper.

6. The system according to claim 5, characterized in that, The metal circuit layer is composed of multiple racetrack-shaped metal wires, with a wire width of 0.1~0.3mm, a wire spacing of 0.2~0.4mm, and a thickness of 0.05~0.2mm.

7. The system according to claim 5, characterized in that, The biocompatible metal layer is selected from at least one of titanium, tungsten, platinum, gold and niobium; the thickness of the biocompatible metal layer is 0.01~0.1 mm.

8. A magnetic resonance wireless power supply method, applied to the system as described in any one of claims 1 to 7, characterized in that, The method includes: Step S1: The external transmitter responds to the initial driving voltage and initiates wireless power transmission; Step S2: The implanted receiver samples the rectified and filtered voltage and feeds it back to the external transmitter. Step S3: If the external transmitter determines that the voltage fed back by the implantable receiver is within the preset tolerance, then the transmitter voltage is adjusted and the process returns to step S2 until the preset number of adjustments is reached and the preset tolerance is met. Then, the handshake is determined to be successful and step S4 is executed. Step S4: The external transmitter calculates the power supply efficiency. If the power supply efficiency is lower than a preset value, it prompts the user to adjust the position. Step S5: After the power supply efficiency reaches a preset value, the system enters a normal operating mode. In the normal operating mode, the external transmitter dynamically adjusts the transmission power according to the voltage feedback from the implanted receiver to make the voltage after rectification and filtering by the implanted receiver relatively stable.

9. The method according to claim 8, characterized in that, The method further includes: If the external transmitter determines that the voltage fed back by the implanted receiver is not within the preset tolerance, it will stop the power supply and issue an alarm.

10. The method according to claim 8, characterized in that, The method further includes: In the normal operating mode, if the external transmitter determines that the first temperature signal is abnormal, it initiates anomaly handling and reporting.

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