A wireless charging circuit with variable resonant inductance
By dynamically adjusting the inductance of the LC resonant circuit in the wireless charging circuit, the problem of limited distance of the wireless charging circuit is solved, and charging and automatic compatibility at longer distances is achieved, which enhances market competitiveness.
Patent Information
- Application Number
- CN202110608392.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2021-06-01
- Publication Date
- 2024-12-27
- Estimated Expiration
- 2041-06-01
AI Technical Summary
The LC resonant circuit in the wireless charging circuit on the market lacks variable additional capacitors, resulting in limited charging distance and unable to float within a large range, limiting the development of wireless technology.
A wireless charging circuit with variable resonant inductance is designed. Through the main control chip, the relay and inductance are controlled, the inductance of the LC resonant circuit is dynamically adjusted, and the alternating voltage and magnetic field radiation force are increased, thereby achieving longer-distance charging.
It realizes automatic compatibility of wireless charging circuits at long and near distances, improves charging distance and market competitiveness, is low cost and effectively solves the problem of limited distance of traditional wireless charging circuits.
Smart Images
Figure CN113141052B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of charging technology, in particular to a wireless charging circuit with variable resonant inductance. Background Art
[0002] The existing wireless charging circuits on the market do not have variable additional capacitance designed for the main coil in the LC resonant circuit, so the wireless charging distance can only fluctuate within a small range. This has hindered the development of wireless technology, so improvements are needed. Summary of the invention
[0003] The object of the present invention is to provide a wireless charging circuit with variable resonant inductance to solve the problems raised in the above background technology.
[0004] To achieve the above object, the present invention provides the following technical solutions:
[0005] A wireless charging circuit with variable resonant inductance comprises an AC-DC module, a power driver, a main control chip, an output coil, a current / voltage acquisition circuit and a communication signal demodulation circuit. The AC-DC module transmits voltage to the power driver and the main control chip in two ways. The output end of the power driver is respectively connected to a relay K1, a relay K2, a relay K3 and a capacitor C1. The other end of the relay K3 is connected to the output coil via an inductor L1. The other end of the relay K2 is connected to the output coil via an inductor L2. The other end of the relay K1 is connected to the output coil. The other end of the capacitor C1 is connected to the output coil and the current / voltage acquisition circuit. The current / voltage acquisition circuit is also connected to the communication signal demodulation circuit and the main control chip. The main control chip is respectively connected to the power driver, the relay K1, the relay K2, the relay K3 and the communication signal demodulation circuit.
[0006] As a further technical solution of the present invention, the output coil and the capacitor C1 form an LC resonant circuit.
[0007] As a further technical solution of the present invention, the main control chip is responsible for signal acquisition, processing, and control signal output of the entire circuit.
[0008] As a further technical solution of the present invention, the current / voltage acquisition circuit sends the acquired working current value to the main control chip for calculating the transmission power.
[0009] As a further technical solution of the present invention, the current / voltage acquisition circuit sends the acquired voltage / current modulation signal to the communication signal demodulation circuit for signal demodulation.
[0010] As a further technical solution of the present invention, the communication signal demodulation circuit demodulates the voltage / current modulation signal from the current / voltage acquisition circuit, restores it to a standard binary signal, and sends it to the main control chip for calculation.
[0011] As a further technical solution of the present invention, the main control chip obtains a power error data packet of the RX end from the standard binary signal from the communication signal demodulation circuit, and performs frequency / duty adjustment on the PWM signal output to the power driver according to the power error data packet, thereby controlling the alternating magnetic field power emitted by the LC resonant circuit to meet the power requirement of the RX end.
[0012] As a further technical solution of the present invention, when the main control chip cannot meet the power requirement of the RX end through normal PWM frequency + duty cycle adjustment, it can be judged that the RX coil is relatively far away. At this time, the main control chip controls Out1, Out2, Out3... to match the LC main resonant coil with an additional inductor of the required inductance to increase the amplitude of the LC circuit, so that the positive / negative amplitude of the alternating voltage in the Coil is higher, and the energy of the alternating magnetic field radiates farther, thereby achieving the purpose of charging at a longer distance.
[0013] As a further technical solution of the present invention, the main control chip also monitors the dynamic values collected by the temperature sensor in the circuit. When the dynamic values collected by the temperature sensor deviate from the threshold set by the program, the output power is reduced or suspended to achieve the purpose of temperature protection.
[0014] As a further technical solution of the present invention, the main control chip also monitors the output power loss of the circuit. When the output power loss value deviates from the threshold set by the program, the output power is reduced or suspended to protect against foreign objects.
[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. For the first time, in a wireless charging circuit, the inductance in the LC resonant circuit is adjusted to increase the LC amplitude, so as to achieve the purpose of charging at a longer distance; 2. The main control chip of the present invention can adjust the additional inductance of the main coil in the LC resonant circuit at any time, so it can automatically be compatible with long / short distance charging; 3. The existing wireless charging circuits on the market do not design variable additional capacitance for the main coil in the LC resonant circuit, so the wireless charging distance can only float within a small range. The "Wireless Charging Circuit with Variable Resonant Inductance" involved in this patent only needs to select the appropriate additional inductance through the Out1, Out2, Out3... control signals according to the distance of the RX coil, so as to increase the amplitude of the LC circuit, make the positive / negative amplitude of the alternating voltage in the main coil higher, and radiate the energy of the alternating magnetic field farther, so as to achieve the purpose of charging at a longer distance; 4. The variable LC resonant inductance circuit of this design is low-cost, but it achieves the function of automatically compatible with long / short distance charging, and improves the market competitiveness of the product. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is the overall principle block diagram of the present invention. DETAILED DESCRIPTION
[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0018] See also Figure 1 Embodiment 1: A wireless charging circuit with variable resonant inductance comprises an AC-DC module, a power driver, a main control chip, an output coil, a current / voltage acquisition circuit and a communication signal demodulation circuit. The AC-DC module transmits voltage to the power driver and the main control chip in two ways. The output end of the power driver is respectively connected to relay K1, relay K2, relay K3 and capacitor C1. The other end of relay K3 is connected to the output coil through inductor L1. The other end of relay K2 is connected to the output coil through inductor L2. The other end of relay K1 is connected to the output coil. The other end of capacitor C1 is connected to the output coil and the current / voltage acquisition circuit. The current / voltage acquisition circuit is also connected to the communication signal demodulation circuit and the main control chip. The main control chip is respectively connected to the power driver, relay K1, relay K2, relay K3 and the communication signal demodulation circuit.
[0019] The AC-DC module provides DC power for the entire circuit. After the direct power enters the circuit, it is transmitted in two ways: A. One way enters the power driver and is converted into high-frequency pulse DC. This high-frequency pulse DC passes through the LC resonant circuit composed of the output coil and the resonant capacitors C1, C2, C3..., and is converted into a high-frequency alternating magnetic field and radiated out as the main power output of the wireless charger; B. The other way provides power to the main control chip and other peripheral circuits to keep the circuit working in an orderly manner. The main control chip is responsible for signal acquisition, processing, and control signal output of the entire circuit. When the main control chip is powered, it first outputs a PWM digital Ping signal to control the power driver to perform digital Ping power output; the current / voltage acquisition circuit sends the collected working current value to the main control chip for calculating the transmission power; the current / voltage acquisition circuit sends the collected voltage / current modulation signal to the communication signal demodulation circuit for signal demodulation; the communication signal demodulation circuit demodulates the voltage / current modulation signal from the current / voltage acquisition circuit, restores it to a standard binary signal, and sends it to the main control chip for calculation;
[0020] The main control chip obtains the power error data packet of the RX end from the standard binary signal from the communication signal demodulation circuit, and adjusts the frequency / duty cycle of the PWM signal output to the power driver according to the power error data packet, controls the alternating magnetic field power emitted by the LC resonant circuit, and meets the power requirement of the RX end; when the main control chip cannot meet the power requirement of the RX end through normal PWM frequency + duty cycle adjustment, it can be judged that the RX coil is far away. At this time, the main control chip controls Out1, Out2, Out3... to match the additional inductance of the required inductance to the LC main resonant coil to increase the amplitude of the LC circuit and make the Coil The positive / negative amplitude of the alternating voltage is higher, and the energy of the alternating magnetic field radiates farther, achieving the purpose of charging at a longer distance; the main control chip also monitors the dynamic values collected by the temperature sensor in the circuit. When the dynamic values collected by the temperature sensor deviate from the threshold set by the program, the output power is reduced or suspended to achieve the purpose of temperature protection; the main control chip also monitors the output power loss of the circuit. When the output power loss value deviates from the threshold set by the program, the output power is reduced or suspended to achieve the purpose of foreign object protection (FOD).
[0021] Embodiment 2: Based on embodiment 1, control technologies such as voltage stabilization and filtering can be added to the AC-DC module to increase control stability.
[0022] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.
[0023] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.
Claims
1. A wireless charging circuit with variable resonant inductance, comprising an AC-DC module, a power driver, a main control chip, an output coil, a current / voltage acquisition circuit and a communication signal demodulation circuit, characterized in that: The AC-DC module transmits voltage to the power driver and the main control chip in two ways. The output end of the power driver is respectively connected to the relay K1, the relay K2, the relay K3 and the capacitor C1. The other end of the relay K3 is connected to the output coil through the inductor L1. The other end of the relay K2 is connected to the output coil through the inductor L2. The other end of the relay K1 is connected to the output coil. The other end of the capacitor C1 is connected to the output coil and the current / voltage acquisition circuit. The current / voltage acquisition circuit is also connected to the communication signal demodulation circuit and the main control chip. The main control chip is respectively connected to the power driver, the relay K1, the relay K2, the relay K3 and the communication signal demodulation circuit; The output coil and capacitor C1 form an LC resonant circuit; The main control chip obtains the power error data packet of the RX end from the standard binary signal from the communication signal demodulation circuit, and adjusts the frequency / duty of the PWM signal output to the power driver according to the power error data packet, controls the alternating magnetic field power emitted by the LC resonant circuit, and meets the power requirement of the RX end.
2. A wireless charging circuit with variable resonant inductance according to claim 1, characterized in that: The main control chip is responsible for signal acquisition, processing, and control signal output of the entire circuit.
3. A wireless charging circuit with variable resonant inductance according to claim 1, characterized in that: The current / voltage acquisition circuit sends the acquired working current value to the main control chip for calculating the transmission power.
4. A wireless charging circuit with variable resonant inductance according to claim 1, characterized in that: The current / voltage acquisition circuit sends the acquired voltage / current modulation signal to the communication signal demodulation circuit for signal demodulation.
5. The wireless charging circuit with variable resonant inductance according to claim 1, characterized in that: The communication signal demodulation circuit demodulates the voltage / current modulation signal from the current / voltage acquisition circuit, restores it into a standard binary signal, and sends it to the main control chip for calculation.
6. A wireless charging circuit with variable resonant inductance according to claim 1, characterized in that: When the main control chip cannot meet the power requirement of the RX end through normal PWM frequency + duty cycle adjustment, it can be judged that the RX coil is far away. At this time, the main control chip controls Out1, Out2, Out3... to match the LC main resonant coil with an additional inductor of the required inductance to increase the amplitude of the LC circuit, make the positive / negative amplitude of the alternating voltage in the Coi l higher, and radiate the energy of the alternating magnetic field farther, so as to achieve the purpose of charging at a longer distance.
7. A wireless charging circuit with variable resonant inductance according to claim 1, characterized in that: The main control chip also monitors the dynamic values collected by the temperature sensor in the circuit. When the dynamic values collected by the temperature sensor deviate from the threshold set by the program, the output power is reduced or suspended to achieve the purpose of temperature protection.
8. The wireless charging circuit with variable resonant inductance according to claim 1, characterized in that: The main control chip also monitors the output power loss of the circuit. When the output power loss value deviates from the threshold value set by the program, the output power is reduced or suspended to protect against foreign objects.