Fan wireless power supply device based on electromagnetic induction

Abstract

The utility model provides a fan wireless power supply device based on electromagnetic induction. The fan wireless power supply device comprises a transmitting end module and a receiving end module, the transmitting end module comprises a high-frequency inverter circuit, a transmitting coil and a transmitting end control circuit; the receiving end module comprises a receiving coil, a rectifying circuit, a voltage stabilizing circuit and a receiving end control circuit; the transmitting coil is connected with a direct-current power supply through a high-frequency inverter circuit; the receiving coil is used for receiving magnetic field energy emitted by the transmitting coil; the receiving coil is connected with a fan through a rectifying circuit and a voltage stabilizing circuit; the receiving end control circuit is used for modulating and outputting voltage and current information to the transmitting end control circuit; the receiving end control circuit is used for modulating and outputting voltage and current information to the transmitting end control circuit. Different from traditional physical connection modes such as connectors and wire harnesses for power supply connection, the wireless power supply technology eliminates physical interfaces, and energy transmission is carried out based on electromagnetic induction. And the high-frequency inversion technology and the magnetic core material coil are adopted, so that the efficiency and the stability of wireless power supply are remarkably improved.

Description

Technical Field

[0001] The utility model relates to the technical field of wireless power transmission, and in particular to a wireless power supply device for a fan based on electromagnetic induction. Background Art

[0002] At present, most fan products on the market use wired power supply. Traditional fan power supply needs to be connected through a wire harness, which limits the flexibility of fan placement. Multi-fan application scenarios have cable confusion, poor air circulation and aesthetic problems. Moreover, due to the existence of the power cord, users are limited by the length of the wire harness when adjusting the fan position, and cannot move the fan as they wish to meet the needs of different scenarios.

[0003] Although some fans use wireless power supply, the current wireless power supply fans have the following significant disadvantages:

[0004] 1) The structure of the wireless fan is mainly described, but the circuits of the transmitter module and the control module are not described in detail. The performance of wireless power supplies designed with different circuits varies greatly, and whether the wireless fan can work reliably depends on the design quality of the wireless power supply.

[0005] 2) Key circuits such as high-frequency inverter circuits use single-ended circuits, which are often used in low-power power supply scenarios and are not suitable for high-power fan application scenarios;

[0006] 3) The transmitting coil and receiving coil use hollow coils, which occupy a large space and have a large magnetic leakage phenomenon, and are not suitable for small space and high efficiency scenarios;

[0007] 4) Using wireless signal transmission closed-loop control without additional voltage stabilization circuit, the output voltage stability at the receiving end is poor.

[0008] Therefore, in order to solve the problems of cable chaos, poor air circulation and aesthetics caused by wired fans, improve the performance and reliability of wireless power supply systems, and meet the power supply needs of high-power fans, it is urgently necessary to provide a fan driven by wireless power supply technology to achieve wireless energy transmission and improve user convenience and safety. Utility Model Content

[0009] In order to solve the above problems, the purpose of the utility model is to propose a wireless power supply device for fans based on electromagnetic induction. Different from the traditional physical connection methods such as connectors and wiring harnesses to connect the power supply, the wireless power supply technology eliminates the physical interface and transmits energy based on electromagnetic induction. The wireless power supply technology is integrated into the fan design. The problems of cable confusion, poor air circulation and aesthetics caused by wired fans are solved. At the same time, the flexibility of fan installation is increased and the risk of cable damage is reduced. The use of high-frequency inverter technology and magnetic core material coils significantly improves the efficiency and stability of wireless power supply.

[0010] Based on the above purpose, the utility model provides a fan wireless power supply device based on electromagnetic induction, including a transmitting end module and a receiving end module; the transmitting end module includes a high-frequency inverter circuit, a transmitting coil and a transmitting end control circuit; the receiving end module includes a receiving coil, a rectifier circuit, a voltage stabilizing circuit and a receiving end control circuit; the transmitting coil is connected to a DC power supply through a high-frequency inverter circuit; the receiving coil is used to receive the magnetic field energy emitted by the transmitting coil; the receiving coil is connected to the fan through a rectifier circuit and a voltage stabilizing circuit; the receiving end control circuit is used to modulate the output voltage and current information to the transmitting end control circuit.

[0011] As a further solution of the utility model, the high-frequency inverter circuit is used to convert the DC input of the DC power supply into an AC output to drive a resonant unit composed of an inductive transmitting coil and a capacitor.

[0012] As a further solution of the utility model, the high-frequency inverter circuit uses a full-bridge MOSFET circuit to convert DC input into AC output, driving the transmitting coil to generate magnetic field energy.

[0013] As a further solution of the utility model, the transmitting coil is arranged inside the transmitting end module and is excited by the alternating current generated by the high-frequency inverter circuit to generate magnetic field energy.

[0014] As a further solution of the utility model, the transmitting end control circuit is used to demodulate the voltage and current modulation signal fed back from the receiving end, and execute PID feedback control to adjust the duty cycle and frequency of the full-bridge converter to control power transmission.

[0015] As a further solution of the present invention, the transmitter control circuit includes a transmitter demodulator and a PID controller. The transmitter demodulator is used to decode the modulation signal fed back by the receiving module, and the PID controller is used to adjust the duty cycle and frequency of the full-bridge converter according to the feedback signal to control the power output.

[0016] As a further solution of the utility model, the receiving coil is arranged inside the fan device, and is used to receive the magnetic field energy emitted by the transmitting end module. The receiving coil is connected to a rectifier circuit for converting the alternating current received by the receiving coil into direct current. The rectifier circuit is a full-wave circuit, a half-wave circuit, a bridge circuit or a voltage doubler circuit.

[0017] As a further solution of the utility model, the rectifier circuit uses a bridge rectifier circuit to convert the alternating current received by the receiving coil into direct current, and removes noise through a filter capacitor.

[0018] As a further solution of the utility model, the receiving end control circuit adopts a capacitor modulation type, regularly connects the capacitor in parallel to the load, generates current and voltage phase difference changes on the transmitting coil of the transmitting end module, and decodes and transmits the receiving end module voltage signal to the transmitting end module according to the current and voltage phase difference changes.

[0019] As a further solution of the utility model, the receiving end control circuit includes a receiving end demodulator and a frequency modulator. The receiving end demodulator is used to decode the modulation signal emitted by the transmitting end module, and the frequency modulator is used to change the resonant frequency according to demand, affecting the modulation signal of the transmitting end to achieve data communication and power regulation.

[0020] As a further solution of the utility model, the voltage stabilizing circuit uses a buck boost topology circuit for voltage stabilization in the latter stage, which is used to adjust the input voltage fluctuation to a constant output voltage. The voltage stabilizing circuit is a buck boost topology circuit, an LDO linear regulator or a Buck topology circuit.

[0021] As a further solution of the utility model, the transmitting coil and the receiving coil are both made of ferrite cores with high magnetic permeability, and ferrite is added to the bottom of the coils, which increases the magnetic conductivity and magnetic blocking effects, improves the energy transmission efficiency, and reduces heat generation and energy loss.

[0022] As a further solution of the present invention, the electromagnetic induction-based wireless power supply device for the fan also includes a fan base and a fan body, the receiving end module is integrated inside the fan body, the transmitting end module is installed in the fan base, and a distance of 1-5mm is maintained between the transmitting end module and the receiving end module for energy transmission.

[0023] As a further solution of the present utility model, the fan base includes a base bracket and a power supply transmitter, the power supply transmitter includes a multi-layer structure consisting of a transmitting coil, a transmitting circuit board, a transmitting isolation plate and an end cover, and the fan body includes a fan frame, fan blades, a receiving isolation plate, a receiving circuit board and a receiving coil; the transmitting circuit board is configured to convert the electric energy provided by an external power supply into high-frequency alternating current suitable for wireless transmission, drive the transmitting coil to generate an alternating magnetic field, and the receiving circuit board is configured to rectify and stabilize the alternating magnetic field energy generated by the transmitting coil captured by the receiving coil, and then supply power to the motor of the fan body to drive the fan blades to rotate.

[0024] Compared with the prior art, the wireless power supply device for a fan based on electromagnetic induction proposed by the utility model has the following beneficial effects:

[0025] 1. Accurate power regulation: Through the PID control method, the transmitter module can monitor the feedback signal of the receiver in real time, and adjust the power output according to the feedback information to achieve precise power control, ensuring that the fan equipment can maintain a stable operating state under different workloads, avoiding performance degradation or damage caused by power fluctuations.

[0026] 2. Stable voltage output: The voltage stabilization circuit in the receiving module can convert the unstable input voltage fluctuations into a stable output voltage, ensuring that the fan equipment has sufficient and stable power supply, which helps to extend the service life of the equipment and improve the working efficiency and stability of the equipment.

[0027] 3. Efficient energy transmission: The ferrite core coils used in the transmitter and receiver modules improve the efficiency of energy transmission, less energy loss and heat generation, thereby reducing energy waste and improving the overall efficiency of the system.

[0028] 4. Data communication function: The receiving module realizes data communication function through the frequency modulator, and can communicate with the transmitting module in two directions, which facilitates the monitoring and control of the system, enabling the operator to understand the operating status of the equipment in real time and make necessary adjustments and controls.

[0029] 5. Improved safety and reliability: The stability and safety of the system are ensured through the application of PID control and the design of the voltage stabilization circuit. Even when the external environment or load changes, the system can respond quickly and maintain stable operation, improving the reliability and safety of the equipment.

[0030] To sum up, the electromagnetic induction-based wireless power supply device for fans of the utility model can not only realize precise power regulation and stable voltage output, but also improve energy transmission efficiency, realize data communication, and enhance the safety and reliability of the system, and has broad application prospects and market potential.

[0031] These and other aspects of the present application will be more concise and understandable in the following description of the embodiments. It should be understood that the above general description and the following detailed description are only exemplary and explanatory and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the utility model. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0033] In the figure:

[0034] Figure 1 This is a structural block diagram of the electromagnetic induction-based wireless power supply device for fans of the present utility model.

[0035] Figure 2 This is a structural block diagram of a transmitter module in a fan wireless power supply device based on electromagnetic induction of the utility model.

[0036] Figure 3 The circuit diagram is a full-bridge inverter circuit in the wireless power supply device for a fan based on electromagnetic induction of the utility model.

[0037] Figure 4 The present invention is a circuit diagram of a full-bridge inverter circuit in a wireless power supply device for a fan based on electromagnetic induction.

[0038] Figure 5 This is a waveform analysis diagram of the full-bridge inverter circuit in the fan wireless power supply device based on electromagnetic induction of the utility model.

[0039] Figure 6 The circuit diagram is a full-bridge high-frequency inverter circuit integrated inside STWBC86 in the electromagnetic induction-based wireless power supply device for fans of the utility model.

[0040] Figure 7 The present invention is a circuit diagram of a transmitter communication control circuit in a fan wireless power supply device based on electromagnetic induction.

[0041] Figure 8 The present invention is a digital PID control block diagram of a fan wireless power supply device based on electromagnetic induction.

[0042] Fig. 9 This is a structural block diagram of a receiving end module in the fan wireless power supply device based on electromagnetic induction of the utility model.

[0043] Fig.10 The utility model is a circuit diagram of a bridge circuit in a wireless power supply device for a fan based on electromagnetic induction.

[0044] Fig.11 This is a waveform analysis diagram of the bridge circuit in the fan wireless power supply device based on electromagnetic induction of the utility model.

[0045] Fig.12 This is a waveform analysis diagram of the receiving end communication control circuit in the fan wireless power supply device based on electromagnetic induction of the utility model.

[0046] Fig.13 The present invention is a circuit schematic diagram of a communication control circuit at a receiving end in a wireless power supply device for a fan based on electromagnetic induction.

[0047] Fig.14The circuit diagram is a Buck boost topology circuit in the electromagnetic induction-based wireless power supply device for fans of the utility model.

[0048] Fig.15 The circuit diagram is a buck boost circuit formed by TI's TPS552872 in the electromagnetic induction-based wireless power supply device for fans of the utility model.

[0049] Fig.16 This is a structural diagram of a magnetic core coil in a fan wireless power supply device based on electromagnetic induction of the utility model.

[0050] Fig.17 This is a structural diagram of the fan wireless power supply device based on electromagnetic induction of the utility model.

[0051] Fig.18 It is a schematic diagram of an explosion of the wireless power supply device for a fan based on electromagnetic induction of the utility model.

[0052] Description of reference numerals in the figures:

[0053] 1-fan base; 2-fan body; 101-transmitter circuit board; 102-transmitter isolation plate; 103-transmitter coil; 201-receiving coil; 202-receiving isolation plate; 203-receiving circuit board. DETAILED DESCRIPTION

[0054] Below, the present application is further described in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form a new embodiment.

[0055] In order to make the purpose, technical solution and advantages of the utility model more clear, the following is a further detailed description of the utility model embodiments in combination with specific embodiments and with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0056] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are intended to distinguish two non-identical entities or non-identical parameters with the same name. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, other steps or units inherent to a process, method, device, product or equipment that includes a series of steps or units.

[0057] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0058] The flowcharts shown in the accompanying drawings are only examples and do not necessarily include all the contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may also be decomposed, combined or partially merged, so the actual execution order may change according to actual conditions.

[0059] At present, there is a lack of detailed description of the circuits of the transmitting module and the control module for wireless fans that use wireless power supply on the market. The performance of wireless power supplies designed with different circuits varies greatly, and whether the wireless fan can work reliably depends on the design quality of the wireless power supply. Key circuits such as high-frequency inverter circuits use single-ended circuits, which are often used in low-power power supply scenarios and are not suitable for high-power fan application scenarios. The transmitting coil and the receiving coil use hollow coils, which occupy a large space and have large magnetic leakage phenomena, and are not suitable for small space and high-efficiency scenarios; using wireless signal transmission closed-loop control, there is no additional voltage stabilization circuit, and the output voltage stability of the receiving end is poor.

[0060] To this end, the utility model proposes a wireless power supply device for a fan based on electromagnetic induction. Different from the traditional physical connection methods such as connectors and wiring harnesses to connect the power supply, the wireless power supply technology eliminates the physical interface and transmits energy based on electromagnetic induction. The wireless power supply technology is integrated into the fan design. The problems of cable confusion, poor air circulation and aesthetics caused by wired fans are solved. At the same time, the flexibility of fan installation is increased and the risk of cable damage is reduced. The high-frequency inverter technology and magnetic core material coil are used to significantly improve the efficiency and stability of wireless power supply.

[0061] In conjunction with the accompanying drawings, some embodiments of the present application are described in detail below. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0062] See also Figure 1 , Figure 2 and Fig. 9As shown, an embodiment of the utility model provides a fan wireless power supply device based on electromagnetic induction, including a transmitter module and a receiver module. The transmitter module includes a high-frequency inverter circuit, a transmitter coil and a transmitter control circuit; the transmitter coil is connected to a DC power supply through a high-frequency inverter circuit; the receiving coil is used to receive the magnetic field energy emitted by the transmitter coil; the high-frequency inverter circuit adopts a full-bridge MOSFET circuit, and adjusts the output frequency and power through a PWM control strategy to optimize the coupling efficiency with the transmitter coil, and controls the PWM circuit through a PID feedback control algorithm to accurately adjust the power output to adapt to different load conditions. The receiving module includes a receiving coil, a rectifier circuit, a voltage stabilizing circuit and a receiving control circuit, and the receiving coil is connected to the fan through a rectifier circuit and a voltage stabilizing circuit; the receiving module is installed inside or outside the fan. The rectifier circuit is connected to the receiving coil for converting the AC power received by the receiving coil into DC power, the voltage stabilizing circuit is connected to the rectifier circuit for stabilizing the output voltage, and the receiving control circuit is used to modulate the output voltage and current information to the transmitter control circuit.

[0063] In this embodiment, see Figure 2 As shown, the high-frequency inverter circuit is used to convert DC input into AC output to drive the resonant unit composed of an inductor transmitting coil and a capacitor. The high-frequency inverter circuit can be divided into a single-ended circuit, a half-bridge circuit, and a full-bridge circuit. Figure 3 As shown, the high-frequency inverter circuit uses a full-bridge MOSFET circuit to convert DC input into AC output, driving the transmitting coil to generate magnetic field energy. The switch tubes S1 and S3 in the high-frequency inverter circuit form a first group of switch tubes; the switch tubes S2 and S4 in the high-frequency inverter circuit form a second group of switch tubes; when the DC power output of the power supply is converted into AC power, the switch tubes in the first group of switch tubes and the second group of switch tubes are not turned on and off at the same time, and one switch tube in a group of switch tubes is turned on, while the other is turned off. When the switch tube S1 in the first group of switch tubes is turned on, the switch tube S3 is turned off; when the switch tube S2 in the second group of switch tubes is turned off, the switch tube S4 is turned on. At this time, the current direction of the input power source flows from the positive direction through the switch tube S1, capacitor C1, transmitting coil L1 and switch tube S4 back to the negative pole of the power source; when the switch tube S1 of the first group of switch tubes is turned off, the switch tube S3 is turned on; the switch tube S4 of the second group of switch tubes is turned off, and the switch tube S2 is turned on, the current direction of the input power source flows from the positive direction through the switch tube S2, capacitor C1, transmitting coil L1 and switch tube S3, and flows back to the negative pole of the power source. According to the current direction of these two times, it can be known that the current direction of the two times is opposite. According to the above continuous operation of the two groups of switch tubes, the DC flowing out of the power source will be converted into AC and added to both ends of the transmitting coil L1. Based on the characteristics of the inductor itself, the transmitting coil L1 will generate a changing current through the AC. This current generates a changing magnetic field in the transmitting coil.

[0064] Based on Faraday's law of electromagnetic induction, when the strength of the magnetic field changes, an induced electromotive force will be generated in the conductor. The receiving end also includes a receiving coil. When the magnetic field generated by the transmitting coil passes through the receiving coil, an induced current will be generated in the receiving coil. Figure 4 and Figure 5 As shown, the detailed circuit and waveform are as follows:

[0065] When the full-bridge inverter is working, the DC signal input at the V1 terminal is converted into an AC signal and transmitted across the inductor L. Figure 5 From the waveform analysis of the figure, we can see that: at T1, HG1 and LG2 are high, capacitor C is forward charged, and there is a positive voltage across L1; at T2, HG2 and LG1 are high, capacitor C is reverse charged, and there is a reverse voltage across L1, and so on. Finally, an AC voltage signal is added to both ends of the transmitting coil and transmitted to the receiving coil.

[0066] For example, see Figure 6 As shown, taking STWBC86 of ST company as an example, it has an internal integrated full-bridge high-frequency inverter circuit, the switching frequency is set to 120-148KHz, and the duty cycle is set to 10%-50%. The transmitting coil inductance is 6.3uH, the resonant capacitor is 0.4uF, and the input voltage is 12V, and an AC signal can be added to both ends of the transmitting coil.

[0067] See also Figure 7 As shown, the transmitting coil is arranged inside the transmitting end module, and is excited by the alternating current generated by the high-frequency inverter circuit to generate magnetic field energy. The transmitting end control circuit is used to demodulate the voltage and current modulation signal fed back by the receiving end, and execute the PID feedback control method to adjust the duty cycle and frequency of the full-bridge converter to control power transmission. Among them, the transmitting end control circuit includes a transmitting end demodulator and a PID controller, the transmitting end demodulator is used to decode the modulation signal fed back by the receiving end module, and the PID controller is used to adjust the duty cycle and frequency of the full-bridge converter according to the feedback signal to control the power output.

[0068] In this embodiment, the transmitter control circuit is responsible for demodulating the voltage and current modulation signals fed back from the receiver, and performing related PID feedback control to adjust the duty cycle and frequency of the full-bridge converter to control power transmission. Figure 7 As shown, the principle of the transmitter control circuit is to remove the carrier from the peak of the AC signal that couples the receiving coil to the transmitting coil, and restore it to the modulation signal VS through the resistor-capacitor filter circuit. The modulation signal contains the voltage and current signals of the receiving end. The voltage and current signals are given to the PWM controller to adjust the duty cycle of the high-frequency inverter circuit switch tube, thereby adjusting the transmitting voltage and current of the transmitting end.

[0069] Among them, the power control adopts PID control mode. The PID controller control law adopts analog PID control or digital PID control. The power transmission control is carried out using PID feedback control. PID feedback control is as follows Figure 8 As shown, Figure 8 Figure 1 is a digital PID control block diagram. The controlled variable i introduced in the PID feedback control definition represents the operating frequency or duty cycle. In order to ensure sufficiently accurate power control, the power transmitter should determine the amplitude of the battery current, which is equal to the primary coil current. When using PID control, the receiver first decodes the control error information fed back by the transmitter to obtain the current transmitter coil current. and c j , calculate the new transmitting coil current according to the formula:

[0070]

[0071] If c j If the value is non-zero, the transmitter will adjust the transmitting coil current within the Tactive time. The entire adjustment process is divided into the following steps:

[0072] (1) The transmitter calculates the error between the current transmitting current and the new transmitting coil current:

[0073]

[0074] (2) The transmitter calculates the relevant parameters of PID based on the error obtained in step (1):

[0075] P (j，i) =K p ·e (j，i)

[0076] I (j，i) =I (j，i-1) -K i ·e (j，i) ·t inner

[0077]

[0078] (3) Add the PID data calculated according to the formula in step (2) to get the total. The obtained PID cannot be greater than the upper limit + Mpid or the lower limit .Mpid. The formula is:

[0079] PID (j，i) =P (j，i) +I (j，i) +D (j，i)

[0080] (4) The transmitter calculates the new control variable v (j，i) , where Sv is the proportionality factor. If the calculated v(j，i) If the value exceeds the specified range, the transmitter will use the specified maximum value Maxv (j，i) replace:

[0081] v (j，i) =v (j，i-1) -S v PID (j，i)

[0082] (5) The transmitter fills the new control variable into the power conversion unit to complete the entire control process. The entire adjustment process will be iterated multiple times until Cj is less than the specified error range. Iteration number i max and the time required t inner Need to satisfy the formula:

[0083] t active =i max ·t inner

[0084] where t active The value range is [1ms, 5ms].

[0085] The above steps can complete the entire PID control and achieve a stable system. In practice, the relevant proportional gain Kp, integral gain Ki, differential gain Kd, integral limit MI, and PID limit MPID will be set for debugging to ultimately achieve a complete loop control effect.

[0086] See also Fig. 9 As shown, the receiving coil is arranged inside the fan device to receive the magnetic field energy emitted by the transmitting module, and the rectifying circuit is a full-wave circuit, a half-wave circuit, a bridge circuit or a voltage doubling circuit. The fan wireless power supply device based on electromagnetic induction also includes a fan base 1 and a fan body 2, the receiving module is integrated inside the fan body 2, the transmitting module is installed in the fan base 1, and a distance of 1-5mm for energy transmission is maintained between the transmitting module and the receiving module.

[0087] See also Fig. 9 and Fig.10 As shown, the rectifier circuit converts the AC power received by the receiving coil into DC power. The rectifier circuit uses a bridge rectifier circuit to convert the AC power received by the receiving coil into DC power, and removes noise through a filter capacitor. Fig.10 and Fig.11As shown in the figure, the AC circuit part of the bridge circuit achieves the purpose of rectification through 4 diodes. When the AC current ACL is positive and ACN is negative, the upper right and lower left diodes are turned on. When the AC current ACL is negative and ACN is positive, the upper left and lower right diodes are turned on. Finally, the voltage applied to both ends of the capacitor is converted from AC to DC. The converted DC is filtered by the capacitor behind to remove high-frequency noise or ripple in the signal, so that the output voltage is more stable.

[0088] See also Fig.12 As shown, the receiving end control circuit adopts a capacitive modulation type, and the capacitor is regularly connected in parallel to the load, so as to generate a current and voltage phase difference change on the transmitting coil of the transmitting end module, and decode and transmit the receiving end module voltage signal to the transmitting end module according to the current and voltage phase difference change. The receiving end control circuit includes a receiving end demodulator and a frequency modulator, wherein the receiving end demodulator is used to decode the modulation signal sent by the transmitting end module, and the frequency modulator is used to change the resonant frequency according to the demand, so as to affect the modulation signal of the transmitting end and realize data communication and power regulation.

[0089] In this embodiment, the data communication coding of the receiving end control circuit adopts capacitor modulation, and the capacitor is regularly connected in parallel to the load, thereby affecting the resonant frequency, and the transmitting end will obtain the carrier signal and perform corresponding PID adjustment. The capacitor is connected in series at the AC1 pin end to change the resonant frequency point, thereby causing the energy passing through the LC to become smaller, and the DC voltage waveform obtained after full-bridge rectification will present the state of 0 and 1. When capacitor modulation is used, the current and voltage phase difference changes will be generated on the transmitting coil at the power supply end, and this change can be used to analyze and decode the receiving end voltage signal to the transmitting end.

[0090] For example, see Fig.13 As shown in the figure, capacitors C2 and C3 are switched at the same time, and the switching frequency of the switch tube inside the chip to the ground is about 2kHz, so a 2k receiving end voltage signal is superimposed on the periodic carrier of the receiving coil. The receiving end voltage signal is fed back from the receiving coil to the transmitting coil, demodulated by the transmitting end control circuit, and finally controls the power transmission of the transmitting end.

[0091] See also Fig.14As shown, the voltage stabilization circuit uses a buck boost topology circuit for voltage stabilization at the rear stage, which is used to adjust the input voltage fluctuation to a constant output voltage. The voltage stabilization circuit is a buck boost topology circuit, an LDO linear voltage regulator or a Buck topology circuit. In this embodiment, a buck boost topology circuit is used for voltage stabilization at the rear stage of the rectifier circuit to adjust the fluctuating input voltage to a constant output voltage, which is suitable for wireless transmission scenarios above 20W and meets the high power requirements of the fan. At the same time, the voltage stabilization circuit is not limited to the buck boost topology circuit. The LDO linear voltage regulator and the Buck topology can meet the same voltage requirements. Among them, the buck boost topology circuit principle can be found in Fig.14 As shown in the figure, when the Q1 switch is turned on, the input voltage charges the inductor, and the diode D2 is cut off; when the Q1 switch is closed, the inductor prevents the current from decreasing, and the induced current charges the load. At this time, the diode D1 is turned on, and the voltage at the lower end of the load is high and the voltage at the upper end is low. If the lower end is used as GND, the output is negative voltage. When the input voltage fluctuates, the control chip stabilizes the output voltage by controlling the duty cycle of the switch Q1.

[0092] For example, see Fig.15 As shown in the figure, taking the buck boost circuit composed of TI's TPS552872 as an example, the appropriate inductor, capacitor and resistor are selected to ensure that the fan power supply voltage can maintain 12V under any dynamic load conditions. The input voltage of TPS552872 is as high as 36V. In boost mode, when the input voltage range is 9V-18V, TPS552872 can provide an output power of 12V / 2A. The chip adopts an average current mode control scheme, and the switching frequency is set at 2MHz by an external resistor. TPS552872 also provides output overcurrent and short-circuit protection functions.

[0093] See also Fig.16 As shown, the transmitting coil and the receiving coil are both made of ferrite cores with high magnetic permeability, and ferrite is added to the bottom of the coil to increase the magnetic conductivity and magnetic shielding effect, improve the energy transmission efficiency, and reduce heat generation and energy loss. Ferrite is added to the bottom of the transmitting and receiving coils to guide the magnetic field, which can improve the quality factor of the coil inductance. In this embodiment, in the transmitting coil and the receiving coil, a ferrite core with high magnetic permeability is selected, which can effectively reduce energy loss and improve the shielding effectiveness of electromagnetic waves. According to the simulation / experimental results, the efficiency of the ferrite core coil can be increased by 20% compared with the air-core coil.

[0094] For example, taking the 12V 0.8A power supply scenario as an example, both the transmitting and receiving coils can use the AWC-A11 coil, use the ferrite core AWF-HY500053100, the inductance is 6.3uH, and the maximum transmitting power is 20W. Fig.16 In the A11 wireless coil, the values ​​of A, B, C, D, E, and F are 50.00±1.00mm, 43.00±1.00mm, 20.00±0.50mm, 5.50±0.50mm, 3.00±1.00mm, and 7.00±1.00mm, respectively. The total thickness of the adhesive backing of the AWC-A11 coil and the magnetic sheet coil adhesive backing cannot exceed 2.60mm.

[0095] See also Fig.17 and Fig.18 As shown, the fan base 1 of the electromagnetic induction-based wireless power supply device for fans includes a base bracket and a power supply transmitter. The base bracket is composed of a bracket body, and is designed with a magnetic suction component for firmly adsorbing and positioning the fan body 2; the transmitter module includes a four-layer structure of a transmitter coil 103, a transmitter circuit board 101, a transmitter isolation plate 102, and an end cover. The transmitter coil 103 is responsible for generating an electromagnetic field, and the transmitter circuit board 101 regulates the generated electromagnetic energy. The transmitter isolation plate 102 ensures the insulation and safety distance between the transmitter coil 103 and the transmitter circuit board 101 to prevent short circuit or electrical interference, and the end cover prevents the transmitter coil 103 from leaking directly.

[0096] The fan body 2 includes a fan frame, fan blades, bearings, a motor, a suction block, a receiving end circuit board 203 and a receiving coil 201, and a receiving isolation sheet 202 arranged between the receiving coil 201 and the receiving end circuit board 203. The fan frame and the fan blades form an air duct, and the motor drives the fan blades to rotate to provide wind power; the magnetic suction block cooperates with the base magnetic attraction, and the fan body 2 is accurately installed on the base through magnetic adsorption and remains stable; the receiving coil 201 senses the magnetic field generated by the base transmitting coil 103, and converts electromagnetic energy into electricity for the fan to work; the receiving end circuit board 203 is responsible for rectifying and stabilizing the received energy and then supplying it to the internal circuit of the fan.

[0097] The transmitting end circuit board 101 is configured to convert the electric energy provided by the external power supply into high-frequency alternating current suitable for wireless transmission, and drive the transmitting coil 103 to generate an alternating magnetic field. The receiving end circuit board 203 is configured to rectify and stabilize the alternating magnetic field energy generated by the transmitting coil captured by the receiving coil 201, and then supply power to the motor of the fan body 2 to drive the fan blades to rotate.

[0098] The electromagnetic induction-based wireless power supply device for fans of the utility model solves the problems of cable confusion, poor air circulation and aesthetics caused by wired fans, increases the flexibility of fan installation, reduces the risk of cable damage, and adopts high-frequency inverter technology and magnetic core material coils to significantly improve the efficiency and stability of wireless power supply. Through the PID control method, the transmitting end module can monitor the feedback signal of the receiving end in real time, and adjust the power output according to the feedback information to achieve precise power control, ensuring that the fan equipment can maintain a stable operating state under different workloads, avoiding performance degradation or damage caused by power fluctuations.

[0099] The electromagnetic induction-based wireless power supply device for fans of the utility model can not only realize precise power regulation and stable voltage output, but also improve energy transmission efficiency, realize data communication, and enhance the safety and reliability of the system, and has broad application prospects and market potential.

[0100] It should be understood that, as used herein, the singular form "a" or "an" is intended to include the plural form, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations of one or more of the items listed in association. The serial numbers of the embodiments disclosed in the above-mentioned embodiments of the utility model are only for description and do not represent the advantages and disadvantages of the embodiments.

[0101] Those skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the above embodiments of the present invention, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A fan wireless power supply device based on electromagnetic induction, characterized in that: It includes a transmitting end module and a receiving end module; the transmitting end module includes a high-frequency inverter circuit, a transmitting coil and a transmitting end control circuit; the receiving end module includes a receiving coil, a rectifier circuit, a voltage stabilizing circuit and a receiving end control circuit; the transmitting coil is connected to a DC power supply through a high-frequency inverter circuit; the receiving coil is used to receive the magnetic field energy emitted by the transmitting coil; the receiving coil is connected to a fan through a rectifier circuit and a voltage stabilizing circuit; the receiving end control circuit is used to modulate the output voltage and current information to the transmitting end control circuit.

2. The fan wireless power supply device based on electromagnetic induction according to claim 1, characterized in that: The high-frequency inverter circuit is used to convert a DC input into an AC output to drive a resonant unit composed of an inductor transmitting coil and a capacitor.

3. The fan wireless power supply device based on electromagnetic induction according to claim 2 is characterized in that: The high-frequency inverter circuit is a full-bridge MOSFET circuit that converts a DC input into an AC output and drives the transmitting coil to generate magnetic field energy.

4. The fan wireless power supply device based on electromagnetic induction according to claim 3 is characterized in that: The transmitting coil is arranged inside the transmitting end module and is excited by the alternating current generated by the high-frequency inverter circuit to generate magnetic field energy.

5. The fan wireless power supply device based on electromagnetic induction according to claim 1, characterized in that: The transmitting end control circuit comprises a transmitting end demodulator for decoding the modulation signal fed back by the receiving end module and a PID controller for adjusting the duty cycle and frequency of the full-bridge converter.

6. The fan wireless power supply device based on electromagnetic induction according to claim 5, characterized in that: The receiving coil is arranged inside the fan device, and the receiving coil is connected to a rectifier circuit for converting the alternating current received by the receiving coil into direct current; the rectifier circuit is a bridge rectifier circuit for converting the alternating current received by the receiving coil into direct current and removing noise through a filter capacitor.

7. The fan wireless power supply device based on electromagnetic induction according to claim 6, characterized in that: The receiving end control circuit includes a receiving end demodulator for decoding the modulation signal sent by the transmitting end module and a frequency modulator for adjusting the resonant frequency.

8. The fan wireless power supply device based on electromagnetic induction according to claim 7, characterized in that: The voltage stabilizing circuit uses a buck boost topology circuit that adjusts input voltage fluctuations to a constant output voltage.

9. The fan wireless power supply device based on electromagnetic induction according to claim 1, characterized in that: The transmitting coil and the receiving coil are both made of a ferrite core with high magnetic permeability, and ferrite is added to the bottom of the coil.

10. The fan wireless power supply device based on electromagnetic induction according to claim 9, characterized in that: The electromagnetic induction-based wireless power supply device for a fan also includes a fan base and a fan body. The receiving end module is integrated inside the fan body, and the transmitting end module is installed in the fan base. A distance of 1-5 mm is maintained between the transmitting end module and the receiving end module for energy transmission.

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