Bidirectional magnetic coupling AC-AC wireless charging system

Abstract

The invention provides a bidirectional magnetic coupling AC-AC wireless charging system, which belongs to the technical field of power electronic wireless charging, and comprises a first rectification filtering unit, an inversion unit and a first resonance unit which are connected with commercial power in sequence, and a second resonance unit, a second rectification filtering unit, a waveform overturning unit and an LC filtering and load unit which are connected in sequence, the second resonance unit and the first resonance unit are magnetically coupled to each other. The beneficial effects are that the movable, safe and reliable bidirectional magnetic coupling type power utilization device capable of converting the AC power supply into the AC power supply is realized.

Description

Technical Field

[0001] This invention relates to the field of power electronics wireless charging technology, and more particularly to a bidirectional magnetic coupling AC-AC wireless charging system. Background Technology

[0002] With the steady development of the social economy and the significant improvement of residents' living standards, various electronic devices have become an indispensable part of people's daily lives, placing higher demands on the convenience and efficiency of device charging. This has led to the emergence of wireless charging technology. Wireless charging technology frees users from the constraints of traditional charging cables, providing a more convenient and free charging experience.

[0003] Currently, wireless charging technology is mainly used in a unidirectional power transfer mode where mains power is supplied to the load. This means that electrical energy is transferred unidirectionally from the mains power supply to the load device, providing the energy needed for charging. However, this unidirectional power transfer method cannot meet the needs of some special scenarios. For example, in some situations, the load device may have excess electrical energy that cannot be fed back to the mains power supply. In other words, existing wireless charging technology cannot achieve bidirectional flow and conversion of electrical energy between the mains power supply and the load. This not only wastes energy and reduces energy efficiency but also limits the application and development of wireless charging technology in a wider range of fields. Summary of the Invention

[0004] To address the above technical problems, this invention provides a bidirectional magnetic coupling AC-AC wireless charging system.

[0005] The technical problem solved by this invention can be achieved by the following technical solutions:

[0006] A bidirectional magnetic coupling AC-AC wireless charging system includes a first rectifier and filter unit, an inverter unit, and a first resonant unit that are sequentially connected to the mains power supply, as well as a second resonant unit, a second rectifier and filter unit, a waveform reversal unit, an LC filter, and a load unit that are sequentially connected to the mains power supply.

[0007] The first rectifier and filter unit is used to rectify and filter the mains input voltage, converting the sinusoidal AC wave into a ripple wave; the inverter unit is used to convert the ripple wave into high-frequency pulsating electrical energy with positive and negative envelopes to drive the first resonant unit.

[0008] The second resonant unit is magnetically coupled to the first resonant unit. The second rectifier and filter unit is used to rectify and filter the modulated wave output by the second resonant unit to obtain the steamed bun wave. The waveform flipping unit is used to flip the steamed bun wave into a sinusoidal AC wave. The LC filter and load unit is used to filter out the high-frequency pulse signal in the sinusoidal AC wave and supply power to the load.

[0009] Preferably, the first rectifier and filter unit includes a first filter inductor, a first diode, a second diode, a third diode, a fourth diode, and a first filter capacitor. One end of the first filter inductor is connected to the mains power. The first diode, the second diode, the third diode, and the fourth diode form a first full-bridge rectifier circuit. The other end of the first filter inductor is connected to the input terminal of the first full-bridge rectifier circuit. The first filter capacitor is connected in parallel to the two output terminals of the first full-bridge rectifier circuit.

[0010] Preferably, the inverter unit includes a first field-effect transistor, a second field-effect transistor, a third field-effect transistor, and a fourth field-effect transistor, wherein the first field-effect transistor, the second field-effect transistor, the third field-effect transistor, and the fourth field-effect transistor constitute a first full-bridge inverter circuit.

[0011] Preferably, the first resonant unit adopts either an S-topology resonant network or an LCC topology resonant network.

[0012] Preferably, the second resonant unit adopts either an S-topology resonant network or an LCC topology resonant network.

[0013] Preferably, the second rectifier and filter unit includes a fifth diode, a sixth diode, a seventh diode, an eighth diode, and a second filter capacitor. The fifth diode, the sixth diode, the seventh diode, and the eighth diode form a second full-bridge rectifier circuit, and the second filter capacitor is connected in parallel to the two output terminals of the second full-bridge rectifier circuit.

[0014] Preferably, the waveform reversing unit includes a fifth field-effect transistor, a sixth field-effect transistor, a seventh field-effect transistor, and an eighth field-effect transistor, which together form a second full-bridge inverter circuit.

[0015] Preferably, the LC filter and load unit includes:

[0016] A second filter inductor, one end of which is connected to an output terminal of the waveform flipping unit;

[0017] The third filter capacitor is connected between the other end of the second filter inductor and the other output terminal of the waveform flipping unit;

[0018] The load is connected in parallel across the third filter capacitor.

[0019] Preferably, it includes a first working mode and a second working mode;

[0020] When operating in the first operating mode, the mains power supplies power to the load;

[0021] When operating in the second operating mode, the load is charged by the mains power.

[0022] Preferably, the voltage frequency of the mains power is the same as the voltage frequency of the load.

[0023] The advantages or beneficial effects of the technical solution of this invention are as follows:

[0024] This invention provides a portable, safe, reliable, bidirectional magnetically coupled AC-to-AC power conversion device by sequentially connecting a first rectifier filter unit, an inverter unit, and a first resonant unit to the mains power supply, as well as a second resonant unit, a second rectifier filter unit, a waveform inversion unit, an LC filter, and a load unit to the mains power supply. The second resonant unit is magnetically coupled to the first resonant unit. Attached Figure Description

[0025] Figure 1 A schematic diagram of the structure of the AC-to-AC wireless charging system with an S / S topology, as shown in a preferred embodiment of the present invention.

[0026] Figure 2 A schematic diagram of the structure of the LCC / S topology AC-to-AC wireless charging system in a preferred embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the structure of an AC-to-AC wireless charging system with an LCC / LCC topology, as described in a preferred embodiment of the present invention. Detailed Implementation

[0028] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0030] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0031] In a preferred embodiment of the present invention, based on the above-mentioned problems existing in the prior art, a bidirectional magnetically coupled AC-AC (alternating current to alternating current) wireless charging system is provided, such as... Figure 1 As shown, it includes:

[0032] The first rectifier and filter unit 1 is connected to the mains power supply E1 and is used to rectify and filter the mains input voltage, converting a sinusoidal alternating wave with a first frequency into a wave with a second frequency higher than the first frequency. Preferably, the second frequency is twice the first frequency.

[0033] Inverter unit 2 is connected to first rectifier filter unit 1 and first resonant unit 3 respectively, and is used to convert the steam wave with second frequency into high-frequency pulsating electrical energy with positive and negative envelopes to drive the first resonant unit.

[0034] The second resonant unit 4 is magnetically coupled to the first resonant unit 3 to obtain a modulated wave;

[0035] The second rectifier and filter unit 5 is connected to the second resonant unit 4 and is used to rectify and filter the modulated wave output by the second resonant unit to obtain a humbucker wave with a second frequency.

[0036] Waveform flipping unit 6 is connected to second rectifier and filter unit 5 and is used to flip a steam wave with a second frequency into a sinusoidal alternating wave with a first frequency.

[0037] The LC filter and load unit 7 is connected to the waveform flipping unit 6 and is used to filter out high-frequency pulse signals in the sinusoidal AC wave to supply power to the load.

[0038] Furthermore, a full-bridge rectifier circuit is used to convert alternating current (AC) signals into direct current (DC) signals. The output frequency of the full-bridge rectifier circuit is twice the input frequency. Specifically, the first frequency is 50Hz–60Hz, and the second frequency is 100Hz–120Hz.

[0039] In a preferred embodiment, the first rectifier filter unit 1 includes a first filter inductor L1, a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, and a first filter capacitor C1.

[0040] The first diode D1, the second diode D2, the third diode D3 and the fourth diode D4 form the first full-bridge rectifier circuit. The first full-bridge rectifier circuit includes a first bridge arm and a second bridge arm. The first diode D1 and the second diode D2 are connected in series to form the first bridge arm, and the third diode D3 and the fourth diode D4 are connected in series to form the second bridge arm.

[0041] One end of the first filter inductor L1 is connected to the positive terminal of the mains power E1, and the other end of the first filter inductor L1 is connected to the midpoint of the first bridge arm. The midpoint of the second bridge arm is connected to the negative terminal of the mains power. The first filter capacitor C1 is connected in parallel to the two output terminals of the first full-bridge rectifier circuit.

[0042] Specifically, the mains input voltage is converted from a 50Hz sinusoidal AC wave to a 100Hz rectified wave by a full-bridge rectifier circuit consisting of a first filter inductor L1, a first diode D1, a second diode D2, a third diode D3, and a fourth diode D4. The high-frequency noise in the rectified wave is then filtered out by the first filter capacitor C1.

[0043] In a preferred embodiment, the inverter unit 2 includes a first field-effect transistor Q1, a second field-effect transistor Q2, a third field-effect transistor Q3, and a fourth field-effect transistor Q4.

[0044] The first field-effect transistor Q1, the second field-effect transistor Q2, the third field-effect transistor Q3, and the fourth field-effect transistor Q4 form the first full-bridge inverter circuit.

[0045] The first full-bridge inverter circuit includes a third bridge arm and a fourth bridge arm. The first field-effect transistor Q1 and the second field-effect transistor Q2 are connected in series to form the third bridge arm, and the third field-effect transistor Q3 and the fourth field-effect transistor Q4 are connected in series to form the fourth bridge arm.

[0046] In this embodiment, the field-effect transistors Q1-Q4 can be selected from, but are not limited to, insulated-gate field-effect transistors and silicon carbide field-effect transistors.

[0047] In a preferred embodiment, the first resonant unit 3 is either an S-topology resonant network or an LCC topology resonant network.

[0048] In a preferred embodiment, the second resonant unit 4 is either an S-topology resonant network or an LCC topology resonant network.

[0049] Specifically, the first resonant unit 3 and the second resonant unit 4 can be selected from resonant networks with S / S topology, LCC / S topology, S / LCC topology, and LCC / LCC topology.

[0050] like Figure 1 A schematic diagram of an AC-to-AC wireless charging system with an S / S topology is shown. The first resonant unit 3 includes a first resonant capacitor C3 and a first resonant inductor L3. One end of the first resonant capacitor C3 is connected to the midpoint of the fourth bridge arm, and the other end of the first resonant capacitor C3 is connected to one end of the first resonant inductor L3. The other end of the first resonant inductor L3 is connected to the midpoint of the third bridge arm.

[0051] The second resonant unit 4 includes a second resonant inductor L4 and a second resonant capacitor C4. The second resonant inductor L4 is magnetically coupled to the first resonant inductor L3. One end of the second resonant inductor L4 is connected to one end of the second resonant capacitor C4, and the other end of the second resonant capacitor C4 is connected to the first input terminal of the second rectifier and filter unit 5. The other end of the second resonant inductor L4 is connected to the second input terminal of the second rectifier and filter unit 5.

[0052] like Figure 2 A schematic diagram of an AC-to-AC wireless charging system with an LCC / S topology is shown. Compared to the S / S topology resonant network, the first resonant unit 3 adds a third resonant inductor L2 and a third resonant capacitor C2, while the structure of the second resonant unit 4 remains unchanged.

[0053] In the first resonant unit 3, one end of the third resonant inductor L2 is connected to the midpoint of the fourth bridge arm; the other end of the third resonant inductor L2 is connected to one end of the first resonant inductor L3 through the first resonant capacitor C3, and is connected to the midpoint of the third bridge arm through the third resonant capacitor C2; the other end of the first resonant inductor L3 is connected to the midpoint of the third bridge arm.

[0054] like Figure 3 A schematic diagram of an AC-to-AC wireless charging system with an LCC / LCC topology is shown. Compared to the LCC / S topology resonant network, the structure of the first resonant unit 3 remains unchanged, while the second resonant unit 4 adds a fourth resonant inductor L5 and a fourth resonant capacitor C5.

[0055] In the second resonant unit 4, the second resonant inductor L4 and the first resonant inductor L3 are magnetically coupled to each other. One end of the second resonant inductor L4 is connected to one end of the second resonant capacitor C4. The other end of the second resonant capacitor C4 is connected to the first input terminal of the second rectifier and filter unit 5 through the fourth resonant inductor L5, and is also connected to the second input terminal of the second rectifier and filter unit 5 through the fourth resonant capacitor C5. The other end of the second resonant inductor L4 is connected to the second input terminal of the second rectifier and filter unit 5.

[0056] In a preferred embodiment, the second rectifier and filter unit 5 includes a fifth diode D5, a sixth diode D6, a seventh diode D7, an eighth diode D8, and a second filter capacitor C6. The fifth diode D5, the sixth diode D6, the seventh diode D7, and the eighth diode D8 form a second full-bridge rectifier circuit, and the second filter capacitor C6 is connected in parallel to the two output terminals of the second full-bridge rectifier circuit.

[0057] Specifically, the second full-bridge rectifier circuit includes a fifth bridge arm and a sixth bridge arm. The fifth bridge arm is formed by connecting the fifth diode D5 and the sixth diode D6 in series, and the midpoint of the fifth bridge arm serves as the first input terminal of the second full-bridge rectifier circuit. The sixth bridge arm is formed by connecting the seventh diode D7 and the eighth diode D8 in series, and the midpoint of the sixth bridge arm serves as the second input terminal of the second full-bridge rectifier circuit.

[0058] The high-frequency carrier wave output by the second resonant unit 4 is mixed with the modulation wave of 50Hz envelope. It is rectified by the second full-bridge rectifier circuit composed of the fifth diode D5, the sixth diode D6, the seventh diode D7 and the eighth diode D8, so as to convert it into a 100Hz pulsating wave. Then, the high-frequency component is filtered out by the second filter capacitor C6 to obtain the 100Hz pulsating wave.

[0059] In a preferred embodiment, the waveform flipping unit 6 includes a fifth field-effect transistor Q5, a sixth field-effect transistor Q6, a seventh field-effect transistor Q7, and an eighth field-effect transistor Q8, which together form a second full-bridge inverter circuit.

[0060] Specifically, the second full-bridge inverter circuit includes a seventh bridge arm and an eighth bridge arm. The fifth field-effect transistor Q5 and the sixth field-effect transistor Q6 are connected in series to form the seventh bridge arm, and the seventh field-effect transistor Q7 and the eighth field-effect transistor Q8 are connected in series to form the eighth bridge arm.

[0061] The waveform flipping unit 6, composed of the fifth field-effect transistor Q5, the sixth field-effect transistor Q6, the seventh field-effect transistor Q7 and the eighth field-effect transistor Q8, flips the 100Hz steam wave into a 50Hz sinusoidal alternating wave.

[0062] In a preferred embodiment, the LC filter and load unit 7 includes a second filter inductor L6, a third filter capacitor C7, and a load R1. One end of the second filter inductor L6 is connected to the midpoint of the eighth bridge arm, and the other end of the second filter inductor L6 is connected to the midpoint of the seventh bridge arm through the third filter capacitor C7. The load R1 is connected in parallel across the two ends of the third filter capacitor C7.

[0063] Specifically, the high-frequency pulse signal in the 50Hz sine wave can be filtered out by the second filter inductor L6 and the third filter capacitor C7, resulting in a clean 50Hz sine wave to power the load R1.

[0064] In a preferred embodiment, a first operating mode and a second operating mode are included;

[0065] When operating in the first working mode, the mains power supplies the load;

[0066] When operating in the second working mode, the load is charged by AC power.

[0067] Specifically, in the first working mode, the mains power E1 serves as the system input terminal, and the load R1 serves as the system output terminal. A 50Hz to 60Hz sinusoidal AC wave can be input from the mains power E1, and after passing through the first rectifier filter unit 1, the inverter unit 2, the first resonant unit 3, the second resonant unit 4, the second rectifier filter unit 5, the waveform reversal unit 6, the LC filter, and the load unit 7, the same sinusoidal AC voltage is obtained across the load R1.

[0068] In the second operating mode, load R1 serves as the system input terminal and mains power E1 serves as the system output terminal. A 50Hz to 60Hz sinusoidal AC wave can be input from both ends of load R1. After passing through LC filtering and load unit 7, waveform reversal unit 6, second rectifier filter unit 5, second resonant unit 4, first resonant unit 3, inverter unit 2, and first rectifier filter unit 1 in sequence, the same sinusoidal AC voltage is obtained at mains power E1.

[0069] In a preferred embodiment, the voltage frequency of the mains power is the same as the voltage frequency of the load.

[0070] Specifically, in this embodiment, AC power is input at the system input terminal, and the transmitter of the synchronous wireless charging system emits high-frequency pulse energy, so that the receiver can receive AC voltage with the same frequency and corresponding voltage.

[0071] In homes or offices, traditional AC power outlets are installed on the floor. The exposed part of the outlet may leak electricity due to damp environments or disrepair over the years. At the same time, the protruding part of the outlet can easily cause people to trip and fall. In addition, using your hands to open and close the outlet for a long time may also cause the risk of electric shock.

[0072] To effectively address the issues of leakage from the power outlet and the risk of tripping over the protruding part, this embodiment embeds the transmitter under the floor tiles or into the back of a desk. The receiver is a non-contact socket that can be placed on the ground or on a desk. Users simply connect their appliances to this socket, and the interface converts AC power to AC power, providing a convenient and safe electrical device.

[0073] Its working principle is as follows: The AC power output of E1 is 220V or 110V. After passing through the first rectifier and filter unit 1, the AC sine wave is converted into a frequency-doubled sine wave. Then, after passing through the inverter unit 2, the frequency-doubled sine wave is converted into a high-frequency pulse carrier and a low-frequency carrier. Subsequently, these carriers are sent into the resonant cavity of the first resonant unit 3, and the energy is transmitted to the receiving coil of the second resonant unit 4 through the transmitting coil of the first resonant unit 3.

[0074] At the receiving end, the high-frequency pulse carrier and the low-frequency carrier pass through the second rectifier and filter unit 5 to separate the frequency-doubled sine wave. Then, the sine wave is flipped into a sine wave by the waveform flipping unit 6; finally, it is filtered by the second filter inductor L6 and the third filter capacitor C7, and a sine wave with the same frequency and voltage as the mains power E1 is obtained at the load R1 at the output end.

[0075] Conversely, the working principle is similar when load R1 is used as the system input and AC power E1 is used as the system output, and will not be elaborated here.

[0076] The above description of the embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principle of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0077] The above are merely preferred embodiments of the present invention and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should recognize that any equivalent substitutions and obvious changes made using the content of this specification and illustrations should be included within the protection scope of the present invention.

Claims

1. A bidirectional magnetically coupled AC-AC wireless charging system, characterized in that, It includes a first rectifier and filter unit, an inverter unit, and a first resonant unit that are sequentially connected to the mains power, as well as a second resonant unit, a second rectifier and filter unit, a waveform inversion unit, an LC filter, and a load unit that are sequentially connected to the mains power. The first rectifier and filter unit is used to rectify and filter the mains input voltage, converting the sinusoidal AC wave into a ripple wave; the inverter unit is used to convert the ripple wave into high-frequency pulsating electrical energy with positive and negative envelopes to drive the first resonant unit. The second resonant unit is magnetically coupled to the first resonant unit. The second rectifier and filter unit is used to rectify and filter the modulated wave output by the second resonant unit to obtain the steamed bun wave. The waveform flipping unit is used to flip the steamed bun wave into a sinusoidal AC wave. The LC filter and load unit is used to filter out the high-frequency pulse signal in the sinusoidal AC wave and supply power to the load.

2. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The first rectifier and filter unit includes a first filter inductor, a first diode, a second diode, a third diode, a fourth diode, and a first filter capacitor. One end of the first filter inductor is connected to the mains power. The first diode, the second diode, the third diode, and the fourth diode form a first full-bridge rectifier circuit. The other end of the first filter inductor is connected to the input terminal of the first full-bridge rectifier circuit. The first filter capacitor is connected in parallel to the two output terminals of the first full-bridge rectifier circuit.

3. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The inverter unit includes a first field-effect transistor, a second field-effect transistor, a third field-effect transistor, and a fourth field-effect transistor, which together form a first full-bridge inverter circuit.

4. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The first resonant unit adopts either an S-topology resonant network or an LCC topology resonant network.

5. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The second resonant unit adopts either an S-topology resonant network or an LCC topology resonant network.

6. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The second rectifier and filter unit includes a fifth diode, a sixth diode, a seventh diode, an eighth diode, and a second filter capacitor. The fifth diode, the sixth diode, the seventh diode, and the eighth diode form a second full-bridge rectifier circuit, and the second filter capacitor is connected in parallel to the two output terminals of the second full-bridge rectifier circuit.

7. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The waveform reversal unit includes a fifth field-effect transistor, a sixth field-effect transistor, a seventh field-effect transistor, and an eighth field-effect transistor. The fifth field-effect transistor, the sixth field-effect transistor, the seventh field-effect transistor, and the eighth field-effect transistor form a second full-bridge inverter circuit.

8. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The LC filter and load unit includes: A second filter inductor, one end of which is connected to an output terminal of the waveform flipping unit; The third filter capacitor is connected between the other end of the second filter inductor and the other output terminal of the waveform flipping unit; The load is connected in parallel across the third filter capacitor.

9. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, Including the first working mode and the second working mode; When operating in the first operating mode, the mains power supplies power to the load; When operating in the second operating mode, the load is charged by the mains power.

10. The bidirectional magnetic coupling AC-AC wireless charging system according to claim 1, characterized in that, The voltage frequency of the mains power is the same as the voltage frequency of the load.

Images