Electromagnetic induction energy efficiency experiment system for bimodal adaptive wireless charging device

Abstract

The invention relates to the technical field of experimental equipment, in particular to an electromagnetic induction energy efficiency experimental system for a bimodal adaptive wireless charging device, which comprises a direct-current power supply, a high-frequency inverter unit, a resonant topology control unit, a bridge rectifier unit and a load control unit which are connected in sequence, the system comprises a resonance topology control unit, a measuring unit, a core processor, a sliding rail and sliding block mechanism and a visual display unit, and the core processor controls the resonance topology control unit to be adaptively switched between a close-distance resonance-free magnetic induction mode and a long-distance LC resonance magnetic resonance mode according to the coil spacing adjusted by the sliding rail and sliding block mechanism. The AC / DC general metering module is used for high-precision measurement, and real-time visual interaction of data is realized through the serial port screen and the LED lamp post group. According to the invention, high-efficiency energy transmission under a full transmission distance is realized, and a parameter optimization basis of the system and a visual experimental analysis platform are provided.

Description

Technical Field

[0001] This invention relates to the field of experimental equipment technology, and in particular to an electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device. Background Technology

[0002] Wireless charging technology, especially that based on electromagnetic induction, has been widely integrated into various electronic devices and systems, including smartphones, wearable devices, home appliances, and even electric vehicles, due to its advantages such as no physical contact, ease of use, and high safety. Its core working principle follows Faraday's law of electromagnetic induction, achieving wireless energy transmission through time-varying magnetic field coupling between transmitting and receiving coils. However, in practical applications, the overall energy transfer efficiency of the system is significantly affected by the interaction of multiple parameters within a complex system encompassing circuitry, magnetic circuitry, and control. Currently, there is a lack of systematic quantitative analysis and clear optimization design criteria regarding the mechanisms by which these key parameters interact and ultimately determine efficiency, which restricts the further application of this technology in high-efficiency, highly adaptable scenarios.

[0003] Currently, the performance of electromagnetic induction wireless charging systems mainly relies on four core elements: circuit topology, coupling mechanism (coil) design, magnetic circuit layout, and control system. Despite numerous studies and products surrounding these elements, existing technologies still suffer from the following recognized significant limitations and areas of ambiguity in technical understanding: (1) Existing technical solutions typically employ a single classical topology, such as the traditional magnetic induction (tightly coupled) mode or magnetic coupling resonance (loosely coupled) mode. Although the industry generally recognizes the differences in transmission distance adaptability between the two, there is a lack of publicly available and rigorous experimental data and simulation comparative analysis regarding the precise quantitative relationship between the efficiency of the two topologies and the transmission distance, the optimal efficiency range, and the critical point for mode switching under given specific parameters (such as coil size, operating frequency, and load conditions). This lack of quantitative data makes it difficult to design an efficient system that can adaptively select the optimal operating mode according to actual working conditions, and also makes the formulation of adaptive control strategies lack a solid theoretical basis and optimization objectives.

[0004] (2) Existing systems generally use traditional planar helical coils with a single shape (such as common circles or squares). The alternating magnetic field generated by these coils is often not concentrated in space, and there is a significant radial magnetic leakage phenomenon. A large number of magnetic field lines fail to effectively penetrate the receiving coil and are scattered in the surrounding space, causing the coupling coefficient between coils to decrease rapidly when the offset or distance increases, which fundamentally limits the energy transmission efficiency and positional fault tolerance.

[0005] (3) At the magnetic circuit design level, there is an inherent defect of back magnetic flux diffusion and interference, which is often overlooked or not fundamentally solved in existing designs. Whether it is a traditional coil or a partially optimized coil, the alternating magnetic field generated during operation not only radiates forward (to the receiving end) but also inevitably diffuses to the back of the coil (in the opposite direction to the receiving end). These backward-dissipated magnetic fluxes are not only a direct source of energy loss, reducing system efficiency, but more importantly, they will generate eddy current effects on electronic components (such as driver circuit boards, batteries or other sensitive modules) that are inevitably placed on the back of the transmitting coil, resulting in unnecessary heat generation, additional losses, and potential electromagnetic interference (EMI), threatening system stability and reliability. Existing solutions mostly adopt simple shielding measures, failing to systematically "guide" or "recycle" this part of the "useless" back magnetic flux to the forward coupling region through magnetic circuit design, turning waste into treasure.

[0006] (4) At the control and human-computer interaction level, there are shortcomings such as the "black box" nature of the system state and the lack of intuitive feedback. Especially in the experimental research, teaching demonstration or product development and debugging stages, existing platforms often lack real-time, multi-dimensional, and visual monitoring and interaction methods for key parameters (such as efficiency, power, frequency, coupling state, etc.). This makes it difficult for researchers, students or engineers to intuitively establish a profound connection between abstract electrical / magnetic quantities and actual physical phenomena and system performance, which is not conducive to understanding the principles, diagnosing problems and verifying and optimizing control strategies.

[0007] In summary, there is an urgent need in this field for a comprehensive technical solution that can systematically optimize four aspects: adaptive circuit topology, efficient coupling mechanism, integrated magnetic circuit design, and visualized interaction methods. Specifically, there is a pressing need for a novel wireless charging device or experimental platform that can: intelligently switch operating modes to broaden the efficient transmission range; employ innovative coupling mechanism designs to improve magnetic field utilization and coupling robustness; effectively suppress back magnetic leakage and enhance forward magnetic coupling through innovative composite magnetic circuit construction; and provide powerful data acquisition and visualization interaction functions to support in-depth analysis, optimization, and teaching demonstrations. Summary of the Invention

[0008] This invention overcomes the shortcomings of the prior art and provides an electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device.

[0009] To achieve the above objectives, the technical solution adopted by the present invention is as follows: This invention discloses an electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device, comprising a DC power supply, a high-frequency inverter unit, a resonant topology control unit, a bridge rectifier unit, a load control unit, a measurement unit, a core processor, a slide rail slider mechanism, a visualization display unit, and a power management unit. The power management unit is used to supply power to the relays in the core processor, the visualization display unit, and the load control unit. The output terminal of the DC power supply is connected to the input terminal of the high-frequency inverter unit, and the output terminal of the high-frequency inverter unit is connected to the transmitter resonant topology control unit. The transmitter resonant topology control unit and the receiver resonant topology control unit transfer energy through electromagnetic induction coupling, and the slide rail slider mechanism is provided between them to adjust the distance between the transmitter and receiver coils. The output terminal of the receiver resonant topology control unit is connected to the input terminal of the bridge rectifier unit, and the output terminal of the bridge rectifier unit is connected to the input terminal of the load control unit. The measurement unit includes an input measurement module disposed in front of the transmitting end resonant topology control unit and an output measurement module disposed in rear of the receiving end resonant topology control unit, which are used to acquire input voltage and current signals and output voltage and current signals, respectively. The core processor is used to output PWM signals to the high-frequency inverter unit to control the switching of its MOSFETs, and to receive voltage and current signals collected by the measurement unit via serial communication. The core processor also interacts with the visualization display unit via serial port, receives control commands issued by the visualization display unit and generates corresponding PWM signals to control the acrylic LED light column, and controls the switching of relays in the load control unit via GPIO signals to achieve load switching control.

[0010] Furthermore, the high-frequency inverter unit includes an isolation drive circuit and an H-bridge circuit; The isolation drive circuit is divided into a low-voltage region and a high-voltage region. The low-voltage region has an input pin that receives two complementary PWM signals from the core processor, as well as a control pin for setting the dead time. The high-voltage region is powered by an external power supply and is connected to the H-bridge circuit through an output pin. The H-bridge circuit consists of four power MOSFETs. The output signal of the isolation drive circuit controls a pair of MOSFETs on the diagonal of the H-bridge circuit to turn on, so that the DC input voltage is converted into a high-frequency square wave AC voltage output.

[0011] Furthermore, the resonant topology control unit includes a ranging module, a relay control module, a switching controller, and a resonant network comprising non-resonant topology channels and LC resonant topology channels; The ranging module is used to measure the distance between the transmitting coil and the receiving coil in real time; The switching controller is configured to: receive the distance signal measured by the ranging module, and when the distance is less than a preset threshold, control the relay control module to connect the non-resonant topology channel; and when the distance is greater than or equal to the preset threshold, control the relay control module to connect the LC resonant topology channel.

[0012] Furthermore, the slide rail slider mechanism includes a slide rail, a slider, an acrylic plate, and Velcro; the slider is slidably mounted on the slide rail; the acrylic plate is mounted on the slider; a portion of the Velcro is fixed to the acrylic plate, and another portion is connected to the coil in the transmitter resonant topology control unit and / or the receiver resonant topology control unit to fix and replaceably mount the coil.

[0013] Furthermore, the bridge rectifier unit includes a full-bridge rectifier circuit and a filter circuit; the full-bridge rectifier circuit is composed of four diodes connected in a closed loop, used to convert the AC power output from the receiving end resonant topology control unit into pulsating DC power; the filter circuit is connected in parallel at the output end of the full-bridge rectifier circuit, used to filter the pulsating DC power to output a smooth DC voltage to the load control unit; wherein, the diodes are Schottky diodes.

[0014] Furthermore, the measurement unit adopts a universal AC / DC metering module; The AC / DC universal metering module is connected to the input terminal of the transmitter resonant topology control unit and the output terminal of the bridge rectifier unit, respectively, and is used to measure the input and output voltage, current and power parameters. The AC / DC universal metering module adopts a TTL level communication interface and communicates serially with the core processor via the MODBUS-RTU protocol.

[0015] Furthermore, the core processor is an STM32F103ZET6 minimum system board; The first set of pins of the core processor is configured to output two complementary PWM signals to the high-frequency inverter unit to control the on and off of its MOSFETs. The second set of serial communication pins of the core processor are respectively connected to the measurement unit and the visualization display unit, for receiving voltage and current data collected by the measurement unit and communicating bidirectionally with the visualization display unit; The third set of GPIO pins of the core processor is connected to the relay in the load control unit, and controls the connection of different loads by outputting high and low level signals; The fourth set of pins of the core processor is configured to output PWM signals to the acrylic LED strip to control its display status; The core processor is configured to perform the following operations: Perform system initialization, and configure GPIO, timers, serial port interrupts, and DMA; The complementary PWM signal is continuously output; The system receives and parses the data from the measurement unit via serial port interrupt, calculates the electromagnetic induction energy efficiency, and sends the result to the visualization display unit. The display data of the acrylic LED light strip is periodically refreshed by a timer interrupt to reflect the electromagnetic induction energy efficiency in real time. In response to the control commands sent by the visualization display unit, the system controls the load selection, power frequency adjustment, and data saving and clearing functions via serial port interrupt.

[0016] Furthermore, the load control unit includes a relay group and a load resistor array; The relay group consists of multiple optocoupler-isolated relays, whose control terminals are connected to the GPIO pins of the core processor and are controlled by the high and low level signals output by the core processor to turn on and off. The load resistor array includes multiple resistors with different resistance values. Each resistor is connected to or disconnected from the output circuit of the bridge rectifier unit through the corresponding switch contact of the optocoupler isolation relay, so as to realize the switchable selection of load resistance value.

[0017] Furthermore, the visualization display unit includes a serial port screen and an acrylic LED light column assembly; The serial port screen is connected to the core processor via a serial communication interface, and is used for: The measurement unit displays the input and output voltage, current, power, and calculated electromagnetic induction efficiency collected by the measurement unit. The system provides an interactive interface to receive user control commands and send them to the core processor. The control commands include load selection, power frequency selection, data saving, and data clearing. The acrylic LED light column group comprises multiple independent LED light columns, and its control terminal is connected to the core processor; The core processor is configured to: control the acrylic LED light column group to light up each light column in sequence, with each lit light column displaying the electromagnetic induction efficiency of a corresponding set of experimental data in real time; when a save data command is received from the serial port screen, fix the display state of the current light column and light up the next light column; when a clear data command is received, clear the display state of all light columns and start displaying again from the first light column.

[0018] This invention addresses the technical deficiencies in the background technology and has the following beneficial effects: Through multi-level collaborative innovation, such as adaptive switching of circuit topology, magnetic field optimization of coupling mechanism, active guidance of magnetic circuit design, precise matching of system parameters, and intelligent visualization of state interaction, this invention not only provides a high-performance and high-safety dual-mode wireless charging experimental device, but also forms a fully verified and systematic solution for optimizing wireless charging energy efficiency, which has important reference value for teaching, scientific research and industry. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other embodiments can be obtained from these drawings without creative effort.

[0020] Figure 1 This is a diagram of the overall architecture of the system. Figure 2 This is a schematic diagram of the isolation drive circuit module components. Figure 3 This is the schematic diagram of an H-bridge circuit. Figure 4 This is a schematic diagram of a bridge rectifier unit. Figure 5 It is a bridge rectifier circuit; Figure 6 The circuit diagram is for AC current during the positive half-cycle. Figure 7 The circuit diagram is for the negative half-cycle of alternating current. Figure 8 Here is a flowchart of the MODBUS-RTU protocol; Figure 9 This is a schematic diagram of the load experiment. Figure 10 PCB layout for load testing; Figure 11 This is a partial screenshot of the serial port screen interface. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0022] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0023] This invention discloses an electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device, comprising a DC power supply, a high-frequency inverter unit, a resonant topology control unit, a bridge rectifier unit, a load control unit, a measurement unit, a core processor, a slide rail slider mechanism, a visualization display unit, and a power management unit. The power management unit is used to supply power to the relays in the core processor, the visualization display unit, and the load control unit. The output terminal of the DC power supply is connected to the input terminal of the high-frequency inverter unit, and the output terminal of the high-frequency inverter unit is connected to the transmitter resonant topology control unit. The transmitter resonant topology control unit and the receiver resonant topology control unit transfer energy through electromagnetic induction coupling, and the slide rail slider mechanism is provided between them to adjust the distance between the transmitter and receiver coils. The output terminal of the receiver resonant topology control unit is connected to the input terminal of the bridge rectifier unit, and the output terminal of the bridge rectifier unit is connected to the input terminal of the load control unit. The measurement unit includes an input measurement module disposed in front of the transmitting end resonant topology control unit and an output measurement module disposed in rear of the receiving end resonant topology control unit, which are used to acquire input voltage and current signals and output voltage and current signals, respectively. The core processor is used to output PWM signals to the high-frequency inverter unit to control the switching of its MOSFETs, and to receive voltage and current signals collected by the measurement unit via serial communication. The core processor also interacts with the visualization display unit via serial port, receives control commands issued by the visualization display unit and generates corresponding PWM signals to control the acrylic LED light column, and controls the switching of relays in the load control unit via GPIO signals to achieve load switching control.

[0024] It should be noted that this system mainly consists of ten parts: a DC power supply, a high-frequency inverter unit, a resonant topology control unit, a bridge rectifier unit, a load control unit, a measurement unit, a core processor, a slide rail mechanism, a visualization display unit, and a power management unit. The overall system architecture diagram is shown below. Figure 1 As shown, its overall design logic is as follows: Power supply: Power is supplied to the core processor, serial port screen, relays and other modules through the power management unit.

[0025] Main circuit connection: DC power supply is used as input signal to the inverter unit and converted into square wave input signal. After passing through the transmitting end resonant unit, the energy is transferred to the receiving end resonant unit by electromagnetic induction between the coils. The distance between the coils is controlled by adding a slide rail slider mechanism between the two. Then, the sine wave output by the receiving end resonant unit is converted into DC signal by the rectifier unit and connected to the load control unit.

[0026] Measurement circuit: The input and output voltage and current are measured by adding measurement modules before the transmitting end resonant unit and after the receiving end resonant unit.

[0027] Control circuit: The STM32 microcontroller sends PWM signals to the inverter unit to control the MOSFETs. Simultaneously, it uses serial communication to acquire measured voltage and current signals and interact with the serial port screen. The signals sent from the serial port screen are processed by the STM32 to generate PWM control signals to control the acrylic LED light column. The GPIO signals control the relay to turn on and off, thus controlling the load.

[0028] Furthermore, the high-frequency inverter unit includes an isolation drive circuit and an H-bridge circuit; The isolation drive circuit is divided into a low-voltage region and a high-voltage region. The low-voltage region has an input pin that receives two complementary PWM signals from the core processor, as well as a control pin for setting the dead time. The high-voltage region is powered by an external power supply and is connected to the H-bridge circuit through an output pin. The H-bridge circuit consists of four power MOSFETs. The output signal of the isolation drive circuit controls a pair of MOSFETs on the diagonal of the H-bridge circuit to turn on, so that the DC input voltage is converted into a high-frequency square wave AC voltage output.

[0029] It should be noted that since this system explores electromagnetic induction phenomena in a wireless charging scenario, a high-frequency inverter unit is needed to convert DC signals into AC signals to generate the subsequent changing magnetic field. The schematic diagram and component diagram of the isolated drive circuit are shown below. Figure 2 As shown, the schematic diagram of the H-bridge circuit is as follows: Figure 3 As shown.

[0030] (1) For the driving circuit: The isolated driver circuit is divided into a low-voltage region and a high-voltage region (for example, the low-voltage region of this isolated driver circuit is defined as the logic control terminal with an operating voltage not exceeding 5V, while the high-voltage region is defined as the power output terminal with a bus voltage in the range of 300V to 600V). The low-voltage region is mainly responsible for signal input and control logic, while the high-voltage region amplifies and outputs the drive signal to drive the H-bridge.

[0031] Pins INA and INB are two input signal pins used to receive complementary PWM signals from the microcontroller, thereby controlling the output state of the driver.

[0032] The DIS pin is an enable control pin. When set to high, it disables both driver outputs; when set to low, it enables the driver outputs.

[0033] Resistors R1 and R2 (51Ω) limit current and match impedance, preventing signal reflection and other issues. Capacitors C2, C3, C5, and C6 filter and remove high-frequency noise, ensuring a clean input signal and providing a stable input for subsequent signal processing. The 3.3V power supply pin powers the logic circuitry in the low-voltage region, ensuring the chip's internal logic functions correctly.

[0034] The DT pin is used to adjust the dead time. By connecting resistors RDT of different values, the dead time can be precisely set according to the formula DT = 10 × RDT. The dead time setting is to prevent two power devices on the same bridge arm from conducting simultaneously, thereby avoiding short-circuit faults.

[0035] The +12V power supply powers the high-voltage area. Capacitors C7, C8, C9, C10, C11, and C12 act as power filter and decoupler, ensuring a stable power supply to the driver and reducing power supply noise interference with the drive signal. R5 limits current and protects circuit components. D1 is a Schottky diode, which acts as a freewheeling diode in the circuit, protecting the circuit from reverse voltage surges.

[0036] D2 and D3 are ordinary small-signal diodes used to prevent signals from high-voltage areas from flowing back into low-voltage areas, thus providing isolation and protection.

[0037] The OUTA and OUTB pins are the output pins of the driver, which are connected to the H-bridge respectively. The driver amplifies the PWM signal input from the low-voltage region to provide sufficient drive capability to control the on and off of the power devices, thereby achieving power control of the load.

[0038] (2) For H-bridge circuits: Power transistors Q2, Q5, Q6, and Q7 form the core of the H-bridge. The OUTA and OUTB outputs of the UCC21540ADWKR control the on / off state of these MOSFETs. When OUTA is high and OUTB is low, Q2 and Q7 are turned on, while Q5 and Q6 are turned off. Current flows from VBATO through Q2, the load, and Q7 to ground, and the load receives a positive voltage, thus achieving forward conduction.

[0039] When OUTA is low and OUTB is high, Q5 and Q6 are turned on, while Q2 and Q7 are turned off. Current flows from VBATO through Q6, the load, and Q5 to ground, reversing the polarity of the load voltage and achieving reverse conduction.

[0040] Furthermore, the resonant topology control unit includes a ranging module, a relay control module, a switching controller, and a resonant network comprising non-resonant topology channels and LC resonant topology channels; The ranging module is used to measure the distance between the transmitting coil and the receiving coil in real time; The switching controller is configured to: receive the distance signal measured by the ranging module, and when the distance is less than a preset threshold, control the relay control module to connect the non-resonant topology channel; and when the distance is greater than or equal to the preset threshold, control the relay control module to connect the LC resonant topology channel.

[0041] In one specific embodiment of the present invention, in order to facilitate experimental research and to ensure that the electromagnetic induction of the coil is efficient in both short and long distance situations, it is necessary to design a corresponding resonant topology control unit that adaptively changes the topology structure according to the change of distance in order to pursue high efficiency.

[0042] At the same time, experiments exploring other factors can be completed by fixing a certain topology. This unit consists of four parts: a ranging module, a relay control module, an STM32 minimum system board, and an LC resonant inductor-capacitor group.

[0043] Its working principle: The ATK-MS53L0M laser ranging module is used to measure the distance between the coils in real time. When the distance between the coils is less than 4mm, the microcontroller interacts with the coils via serial communication and sends a corresponding control signal to open the non-resonant topology channel. At this time, the wireless charging method is magnetic induction coupling. When the distance between the coils is greater than or equal to 4mm, the corresponding LC resonant topology channel is opened. At this time, the wireless charging method is LC resonant.

[0044] Furthermore, the slide rail slider mechanism includes a slide rail, a slider, an acrylic plate, and Velcro; the slider is slidably mounted on the slide rail; the acrylic plate is mounted on the slider; a portion of the Velcro is fixed to the acrylic plate, and another portion is connected to the coil in the transmitter resonant topology control unit and / or the receiver resonant topology control unit to fix and replaceably mount the coil.

[0045] It should be noted that the slide rail and slider mechanism consists of a stainless steel metal slide rail and a slider, with an acrylic plate assembled on top of the slider and Velcro fastened to the acrylic plate. At the same time, an acrylic plate and the other side of the Velcro are also attached to the back of each coil to facilitate coil replacement in subsequent experiments.

[0046] Furthermore, the bridge rectifier unit includes a full-bridge rectifier circuit and a filter circuit; the full-bridge rectifier circuit is composed of four diodes connected in a closed loop, used to convert the AC power output from the receiving end resonant topology control unit into pulsating DC power; the filter circuit is connected in parallel at the output end of the full-bridge rectifier circuit, used to filter the pulsating DC power to output a smooth DC voltage to the load control unit; wherein, the diodes are Schottky diodes.

[0047] It should be noted that a bridge rectifier unit mainly consists of two parts: a full-bridge rectifier circuit and a filter circuit. It converts the alternating current obtained after electromagnetic induction into direct current and transfers it to the load. The corresponding schematic diagram is shown below. Figure 4 As shown.

[0048] Its working principle: A bridge rectifier circuit can convert alternating current (AC) to direct current (DC). A bridge rectifier consists of four diodes connected in a closed loop, resulting in lower design costs. Its circuit diagram is shown below. Figure 5 As shown. The voltage directly rectified by the rectifier bridge is not smooth enough and needs to be corrected by a filter circuit. Two capacitors are connected in parallel at the output to reduce the AC component in the pulsating DC voltage while retaining its DC component, thus reducing the output voltage ripple coefficient and making the waveform smoother, thereby obtaining a stable voltage. When the input AC waveform is between the positive half-cycles, due to the unidirectional conductivity of the diodes, such as... Figure 6 As shown, the current first flows through diode D1, then through the load from top to bottom, and then flows from D4 to the AC source; when the input AC waveform is between the negative half-cycles, as... Figure 7 As shown, the current first flows through diode D3, then through the load from top to bottom, and then flows from D2 to the AC source.

[0049] Regarding hardware selection, the diodes in this rectifier circuit are MBR60200PT, with a rated current of 30A and a withstand voltage of 100V. These are all Schottky diodes. Schottky diodes are characterized by low forward voltage drop, fast switching speed, and short reverse recovery time, making them suitable for high-frequency rectification applications.

[0050] Furthermore, the measurement unit adopts a universal AC / DC metering module; The AC / DC universal metering module is connected to the input terminal of the transmitter resonant topology control unit and the output terminal of the bridge rectifier unit, respectively, and is used to measure the input and output voltage, current and power parameters. The AC / DC universal metering module adopts a TTL level communication interface and communicates serially with the core processor via the MODBUS-RTU protocol.

[0051] It should be noted that for voltage and current measurements during the experiment, this system uses the JSY-MK-1031 AC / DC universal metering module, which can accurately measure single-phase AC parameters (voltage, current, power, power factor, frequency, and charge, etc.) and DC parameters (voltage, current, power, and charge). It uses TTL level as the data communication interface, is completely isolated from high-voltage areas, and features small size, simple interface, wide current measurement range, and high flexibility. It can be easily embedded into various devices that require power consumption measurement, making it very convenient to use.

[0052] Its working principle: This module adopts the standard MODBUS-RTU protocol. After the host computer sends a data frame to it, the host computer receives a response from the slave device. By comparing the CRC checksum, the accuracy of the collected data can be ensured. Table 1 shows the message format of its transmitted data. Figure 8 This is a flowchart of the MODBUS-RTU protocol.

[0053] Furthermore, the core processor is an STM32F103ZET6 minimum system board; The first set of pins of the core processor is configured to output two complementary PWM signals to the high-frequency inverter unit to control the on and off of its MOSFETs. The second set of serial communication pins of the core processor are respectively connected to the measurement unit and the visualization display unit, for receiving voltage and current data collected by the measurement unit and communicating bidirectionally with the visualization display unit; The third set of GPIO pins of the core processor is connected to the relay in the load control unit, and controls the connection of different loads by outputting high and low level signals; The fourth set of pins of the core processor is configured to output PWM signals to the acrylic LED strip to control its display status; The core processor is configured to perform the following operations: Perform system initialization, and configure GPIO, timers, serial port interrupts, and DMA; The complementary PWM signal is continuously output; The system receives and parses the data from the measurement unit via serial port interrupt, calculates the electromagnetic induction energy efficiency, and sends the result to the visualization display unit. The display data of the acrylic LED light strip is periodically refreshed by a timer interrupt to reflect the electromagnetic induction energy efficiency in real time. In response to the control commands sent by the visualization display unit, the system controls the load selection, power frequency adjustment, and data saving and clearing functions via serial port interrupt.

[0054] It should be noted that the STM32F103ZET6 minimum system board is used as the core controller to control the various modules and achieve the cooperation between the hardware and software. Microcontroller workflow: First, initialization is performed, including GPIO pins, timers, serial port interrupts, DMA, etc. Then the microcontroller begins to continuously output complementary PWM signals to the inverter unit; At the same time, the voltage and current of the circuit collected by the measurement unit are received in real time using the serial port interrupt. After parsing the collected data, the conversion efficiency of electromagnetic induction is calculated and transmitted to the serial port screen for display through another serial port. Call the TIM6 interrupt to refresh the LED strip data every 200ms, so that it can display the collected electromagnetic induction efficiency in real time; After the experiment begins, when the load or power frequency selection switch button on the serial port screen is clicked, data will be transmitted to the microcontroller via USART1. The microcontroller then selects the load and power frequency via serial port interrupt. When you click "Save Data" on the serial port screen, the serial port interrupt will be called, causing the microcontroller to fix the first LED column at the last value and start measuring the next value. When you click "Clear Data" on the serial port screen, the values ​​of the LED column group will be cleared and the measurement will start again from the first LED column.

[0055] Furthermore, the load control unit includes a relay group and a load resistor array; The relay group consists of multiple optocoupler-isolated relays, whose control terminals are connected to the GPIO pins of the core processor and are controlled by the high and low level signals output by the core processor to turn on and off. The load resistor array includes multiple resistors with different resistance values. Each resistor is connected to or disconnected from the output circuit of the bridge rectifier unit through the corresponding switch contact of the optocoupler isolation relay, so as to realize the switchable selection of load resistance value.

[0056] It should be noted that the load control unit consists of two parts: a relay and a load assembly. Using a microcontroller to send control signals allows for flexible replacement of the load resistor, making it easier to conduct load-related experiments. The corresponding schematic diagram is shown below. Figure 9 As shown and the corresponding PCB diagram Figure 10 As shown.

[0057] The load control unit works by using four 5V optocoupler-isolated relays, which are stable in performance. It uses a high-level triggering method and controls the selected load size by switching the relays between high and low levels through the microcontroller's I / O port. The load sizes include 10Ω, 15Ω, 20Ω, 25Ω, 30Ω, 35Ω, 40Ω, and 50Ω.

[0058] Furthermore, the visualization display unit includes a serial port screen and an acrylic LED light column assembly; The serial port screen is connected to the core processor via a serial communication interface, and is used for: The measurement unit displays the input and output voltage, current, power, and calculated electromagnetic induction efficiency collected by the measurement unit. The system provides an interactive interface to receive user control commands and send them to the core processor. The control commands include load selection, power frequency selection, data saving, and data clearing. The acrylic LED light column group comprises multiple independent LED light columns, and its control terminal is connected to the core processor; The core processor is configured to: control the acrylic LED light column group to light up each light column in sequence, with each lit light column displaying the electromagnetic induction efficiency of a corresponding set of experimental data in real time; when a save data command is received from the serial port screen, fix the display state of the current light column and light up the next light column; when a clear data command is received, clear the display state of all light columns and start displaying again from the first light column.

[0059] It should be noted that the visualization display unit includes: (1) Serial port screen A 7-inch serial port display from Taojingchi was used, and the accompanying USART HMI software was used to write code and design the interface on a host computer to complete the interaction between the serial port display and the microcontroller. This enabled the collection of various experimental data and its visualization. A partial view of the serial port display interface is shown below. Figure 11 As shown.

[0060] After the startup animation finishes, the main page will appear. From the main page, you can select different experiments to enter the measurement interface. The measurement interface will display the currently acquired input and output voltages and power in real time, as well as the current efficiency. The "Save Data" button records the current efficiency and displays it on the curve control, while the "Clear Data" button clears all recorded efficiencies. When investigating load, power supply frequency, and resonant frequency, you can switch between load and frequency by clicking the corresponding buttons.

[0061] (2) Acrylic LED light column assembly The light column assembly consists of a self-made PCB base, acrylic blocks, WS2812B LED strips, and 16 M4 screw posts. The assembly contains a total of 8 light columns. At the start of the experiment, the first light column displays the efficiency of the first set of data in real time. When the "Save Data" button is pressed on the serial port screen, the first light column remains unchanged, while the second light column lights up and displays the efficiency of the second set of data in real time, and so on, until all data has been measured. When the "Clear Data" button is pressed on the serial port screen, all data from all light columns is cleared, and the efficiency measurement of the first set of data restarts.

[0062] In the specific implementation process of this invention: 1. Experimental Preparation Simulation: First, efficiency simulation calculations were performed on the investigation factors on the Maxwell and Simulink platforms.

[0063] Equipment check: Ensure all equipment functions correctly. Turn on the power and check if the microcontroller outputs a complementary PWM signal. Press the microcontroller reset button to restore the device to its initial state.

[0064] Coil preparation: Select two corresponding coils, one as the transmitter and the other as the receiver, and connect them to the circuit. Attach the coils to the track frame and adjust and align the two coils. Calculate the corresponding resonant capacitance and adjust the capacitor bank in the system to the calculated value.

[0065] 2. Set experimental parameters Click on the power frequency exploration interface on the main screen to select a suitable frequency, then click on the load exploration interface to select a suitable resistor, and adjust the power supply to a suitable voltage.

[0066] 3. Data Collection On the main interface of the serial port screen, select the experimental function corresponding to the research content, such as "Distance Research", "Topology Research", "Load Research", etc.

[0067] 4. Change experimental parameters Change the variable to be controlled, keep other variables constant, and record the energy conversion efficiency; Save data: After completing each set of experiments, click "Save Data" on the screen to save the current energy conversion efficiency to the coordinate system on the screen. At the same time, the lamp post and serial port screen will record the magnitude of the energy conversion efficiency at this time.

[0068] 5. Data Analysis Data processing: Display the recorded transmission efficiency using charts.

[0069] Data Analysis: Analyze the impact of topology on transmission efficiency based on charts.

[0070] Based on the above embodiments, the technical solution provided by the present invention brings the following technical effects: (1) Through an innovative dual-mode adaptive topology scheme, the system can automatically switch to a high-efficiency magnetic induction (tight coupling) mode at close range and a highly adaptable magnetic resonance (resonance) mode at long range based on real-time distance perception. This intelligent switching mechanism effectively overcomes the inherent limitation of a single topology mode having a sharp drop in efficiency at a specific distance, thereby maintaining the optimal energy conversion efficiency throughout the entire effective transmission space.

[0071] (2) By adopting a co-directional concentric circular ring coupling coil structure, the magnetic field superposition effect of the co-directional current is utilized to form a magnetic field with higher intensity and more concentrated distribution in the central region of the coil. This design effectively constrains the radial divergence of the magnetic field and reduces leakage magnetic field, thereby effectively improving the coupling coefficient between coils under the same conditions and enhancing the stability and anti-interference ability of the system when it is horizontally offset.

[0072] (3) A manganese-zinc ferrite magnetic shielding sheet and a magnetic core with a specific arrangement are introduced on the back of the coil to form a high-efficiency composite magnetic circuit. This design can not only effectively absorb and constrain stray magnetic flux that diffuses to the back of the coil, preventing energy waste and eddy current interference to the back circuit, but also guide this part of the magnetic flux to the forward coupling region, turning waste into treasure, further enhancing the forward magnetic field strength, and improving the transmission efficiency and system safety from the essence of the magnetic circuit.

[0073] (4) Through comprehensive simulation and experimental analysis of coil geometric parameters (shape, number of turns, radius), electromagnetic parameters (power supply frequency, resonant frequency) and load conditions, this scheme systematically and quantitatively reveals the influence of each key parameter on the final transmission efficiency and clarifies its optimal matching range. This provides accurate data basis and reproducible optimization path for the engineering design of similar wireless charging systems.

[0074] (5) A multi-layered, real-time dynamic visualization system was constructed by integrating a serial port touch screen and an LED light column group. This platform can display input / output voltage, current, power, and core energy efficiency data in real time, and present the abstract energy efficiency values ​​in an intuitive graphical representation through the height of the LED light columns. At the same time, all experimental parameters (such as load, frequency, and working mode) can be set and switched through the touch screen interface, simplifying the complex system control and data analysis process into an intuitive interactive operation, thereby improving the efficiency and experience of teaching demonstrations and scientific research debugging.

[0075] (6) The system integrates overvoltage and overcurrent detection and audible and visual alarm functions. When the circuit parameters are detected to exceed the safety threshold, the system can automatically trigger an alarm to prompt the operator to intervene in time, effectively preventing equipment damage or safety hazards caused by misoperation or abnormal device, and ensuring the stable and reliable operation of the experiment.

[0076] In summary, this invention, through multi-level collaborative innovation including adaptive switching of circuit topology, magnetic field optimization of coupling mechanism, active guidance of magnetic circuit design, precise matching of system parameters, and intelligent visualization of state interaction, not only provides a high-performance and high-safety dual-mode wireless charging experimental device, but also forms a fully verified and systematic solution for optimizing wireless charging energy efficiency, which has important reference value for teaching, scientific research and industry.

[0077] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods, such as: multiple units or components can be combined, or integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the various components shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0078] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units. They may be located in one place or distributed across multiple network units. Some or all of the units may be selected to achieve the purpose of this embodiment according to actual needs.

[0079] In addition, in the various embodiments of the present invention, each functional unit can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the integrated unit can be implemented in hardware or in the form of hardware plus software functional units.

[0080] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0081] Alternatively, if the integrated units of this invention are implemented as software functional modules and sold or used as independent products, they can also be stored in a computer-readable storage medium. Based on this understanding, the technical solutions of the embodiments of this invention, or the parts that contribute to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as mobile storage devices, ROM, RAM, magnetic disks, or optical disks.

[0082] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An experimental system for electromagnetic induction energy efficiency of a dual-mode adaptive wireless charging device, characterized in that, It includes a DC power supply, a high-frequency inverter unit, a resonant topology control unit, a bridge rectifier unit, a load control unit, a measurement unit, a core processor, a slide rail slider mechanism, a visualization display unit, and a power management unit; The power management unit is used to supply power to the relays in the core processor, the visualization display unit, and the load control unit. The output terminal of the DC power supply is connected to the input terminal of the high-frequency inverter unit, and the output terminal of the high-frequency inverter unit is connected to the transmitter resonant topology control unit. The transmitter resonant topology control unit and the receiver resonant topology control unit transfer energy through electromagnetic induction coupling, and the slide rail slider mechanism is provided between them to adjust the distance between the transmitter and receiver coils. The output terminal of the receiver resonant topology control unit is connected to the input terminal of the bridge rectifier unit, and the output terminal of the bridge rectifier unit is connected to the input terminal of the load control unit. The measurement unit includes an input measurement module located in front of the transmitting end resonant topology control unit and an output measurement module located behind the receiving end resonant topology control unit, which are used to acquire input voltage and current signals and output voltage and current signals, respectively.

2. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The high-frequency inverter unit includes an isolation drive circuit and an H-bridge circuit; The isolation drive circuit is divided into a low-voltage region and a high-voltage region. The low-voltage region has an input pin that receives two complementary PWM signals from the core processor, as well as a control pin for setting the dead time. The high-voltage region is powered by an external power supply and is connected to the H-bridge circuit through an output pin. The H-bridge circuit consists of four power MOSFETs. The output signal of the isolation drive circuit controls a pair of MOSFETs on the diagonal of the H-bridge circuit to turn on, so that the DC input voltage is converted into a high-frequency square wave AC voltage output.

3. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The resonant topology control unit includes a ranging module, a relay control module, a switching controller, and a resonant network containing non-resonant topology channels and LC resonant topology channels; The ranging module is used to measure the distance between the transmitting coil and the receiving coil in real time; The switching controller is configured to: receive the distance signal measured by the ranging module, and when the distance is less than a preset threshold, control the relay control module to connect the non-resonant topology channel; and when the distance is greater than or equal to the preset threshold, control the relay control module to connect the LC resonant topology channel.

4. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The slide rail and slider mechanism includes a slide rail, a slider, an acrylic plate, and Velcro; the slider is slidably mounted on the slide rail; the acrylic plate is mounted on the slider; a portion of the Velcro is fixed to the acrylic plate, and another portion is connected to a coil in the transmitter resonant topology control unit and / or the receiver resonant topology control unit to fix and replaceably mount the coil.

5. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The bridge rectifier unit includes a full-bridge rectifier circuit and a filter circuit. The full-bridge rectifier circuit consists of four diodes connected in a closed loop to convert the AC power output from the receiving end resonant topology control unit into pulsating DC power. The filter circuit is connected in parallel to the output of the full-bridge rectifier circuit to filter the pulsating DC power and output a smooth DC voltage to the load control unit. The diodes are Schottky diodes.

6. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The measurement unit adopts a universal AC / DC metering module; The AC / DC universal metering module is connected to the input terminal of the transmitter resonant topology control unit and the output terminal of the bridge rectifier unit, respectively, and is used to measure the input and output voltage, current and power parameters. The AC / DC universal metering module adopts a TTL level communication interface and communicates serially with the core processor via the MODBUS-RTU protocol.

7. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The core processor is an STM32F103ZET6 minimum system board; The first set of pins of the core processor is configured to output two complementary PWM signals to the high-frequency inverter unit to control the on and off of its MOSFETs. The second set of serial communication pins of the core processor are respectively connected to the measurement unit and the visualization display unit, for receiving voltage and current data collected by the measurement unit and communicating bidirectionally with the visualization display unit; The third set of GPIO pins of the core processor is connected to the relay in the load control unit, and controls the connection of different loads by outputting high and low level signals; The fourth set of pins of the core processor is configured to output PWM signals to the acrylic LED strip to control its display status; The core processor is configured to perform the following operations: Perform system initialization, and configure GPIO, timers, serial port interrupts, and DMA; The complementary PWM signal is continuously output; The system receives and parses the data from the measurement unit via serial port interrupt, calculates the electromagnetic induction energy efficiency, and sends the result to the visualization display unit. The display data of the acrylic LED light strip is periodically refreshed by a timer interrupt to reflect the electromagnetic induction energy efficiency in real time. In response to the control commands sent by the visualization display unit, the system controls the load selection, power frequency adjustment, and data saving and clearing functions via serial port interrupt.

8. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The load control unit includes a relay group and a load resistor array; The relay group consists of multiple optocoupler-isolated relays, whose control terminals are connected to the GPIO pins of the core processor and are controlled by the high and low level signals output by the core processor to turn on and off. The load resistor array includes multiple resistors with different resistance values. Each resistor is connected to or disconnected from the output circuit of the bridge rectifier unit through the corresponding switching contact of the optocoupler isolation relay, so as to realize the selectable load resistance value.

9. The electromagnetic induction energy efficiency experimental system for a dual-mode adaptive wireless charging device according to claim 1, characterized in that: The visualization display unit includes a serial port screen and an acrylic LED light column assembly; The serial port screen is connected to the core processor via a serial communication interface, and is used for: The measurement unit displays the input and output voltage, current, power, and calculated electromagnetic induction efficiency collected by the measurement unit. The system provides an interactive interface to receive user control commands and send them to the core processor. The control commands include load selection, power frequency selection, data saving, and data clearing. The acrylic LED light column group comprises multiple independent LED light columns, and its control terminal is connected to the core processor; The core processor is configured to: control the acrylic LED light column group to light up each light column in sequence, with each lit light column displaying the electromagnetic induction efficiency of a corresponding set of experimental data in real time; when a save data command is received from the serial port screen, fix the display state of the current light column and light up the next light column; when a clear data command is received, clear the display state of all light columns and start displaying again from the first light column.

10. The electromagnetic induction energy efficiency experimental system for a dual-modal adaptive wireless charging device according to claim 1, characterized in that: The core processor is used to output PWM signals to the high-frequency inverter unit to control the switching of its MOSFETs, and to receive voltage and current signals collected by the measurement unit via serial communication. The core processor also interacts with the visualization display unit via serial port, receives control commands issued by the visualization display unit and generates corresponding PWM signals to control the acrylic LED light column, and controls the switching of relays in the load control unit via GPIO signals to achieve load switching control.

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