CN221353954U - Charging circuit, charging system and vehicle - Google Patents

Abstract

The utility model discloses a charging circuit, a charging system and a vehicle, wherein the charging circuit comprises: the wireless charging system comprises a switching circuit, a wireless charging receiving unit, a charging interface and a vehicle-mounted charging unit; the first end of the switching circuit is connected with the first end of the vehicle-mounted charging unit, the second end of the switching circuit is connected with the wireless charging receiving unit, the third end of the switching circuit is connected with the second end of the vehicle-mounted charging unit, the third end of the vehicle-mounted charging unit is connected with the charging interface, and the fourth end of the vehicle-mounted charging unit is suitable for being connected with a battery of a vehicle. Through newly increasing switching circuit and wireless receiving cell that charges in charging circuit, under wireless charging mode, switching circuit's first end is connected with the second end electricity, and from this wireless receiving cell that charges and on-vehicle machine charge for the battery, under conduction charging mode, switching circuit's first end is connected with the third end electricity, from this on-vehicle machine charges for the battery, compares in the correlation technique, has improved the flexibility of charging.

Description

Charging circuit, charging system and vehicle

Technical Field

The application relates to the field of vehicles, in particular to a charging circuit, a charging system and a vehicle.

Background

New energy vehicles typically include a charging circuit for charging a battery and a battery. The charging circuit may include an On Board Charger (OBC) or a wireless charging receiver circuit. The wireless charging receiving circuit can comprise a receiving coil, a resonant circuit and a rectifying circuit, and the wireless charging receiving circuit is used for acquiring electric energy from an alternating magnetic field generated by a wireless charging ground terminal, so that wireless transmission of the electric energy is realized. But the flexibility of existing charging is low.

Disclosure of utility model

The present utility model aims to solve at least one of the technical problems in the related art to some extent. Therefore, a first object of the present utility model is to provide a charging circuit, in which a switching circuit and a wireless charging receiving unit are newly added, and in a wireless charging mode, a first end of the switching circuit is electrically connected to a second end, so that the wireless charging receiving unit and a vehicle-mounted charger charge a battery, and in a conductive charging mode, a first end of the switching circuit is electrically connected to a third end, so that the vehicle-mounted charger charges the battery, and the charging flexibility is improved compared with the related art.

A second object of the present utility model is to propose a charging system.

A third object of the present utility model is to propose a vehicle.

According to an embodiment of the present utility model, a charging circuit adapted to charge a battery of a vehicle includes: the wireless charging system comprises a switching circuit, a wireless charging receiving unit, a charging interface and a vehicle-mounted charging unit; the first end of the switching circuit is connected with the first end of the vehicle-mounted charging unit, the second end of the switching circuit is connected with the wireless charging receiving unit, the third end of the switching circuit is connected with the second end of the vehicle-mounted charging unit, the third end of the vehicle-mounted charging unit is connected with the charging interface, and the fourth end of the vehicle-mounted charging unit is suitable for being connected with a battery of a vehicle. Through newly increasing switching circuit and wireless receiving cell that charges in charging circuit, under wireless charging mode, switching circuit's first end is connected with the second end electricity, and from this wireless receiving cell that charges and on-vehicle machine charge for the battery, under conduction charging mode, switching circuit's first end is connected with the third end electricity, from this on-vehicle machine charges for the battery, compares in the correlation technique, has improved the flexibility of charging.

In some embodiments of the utility model, the switching circuit comprises a relay.

In some embodiments of the present utility model, a wireless charging receiving unit includes: a resonant circuit and a receiving coil;

The first end of the resonant circuit is connected with the first end of the receiving coil, and the second end of the resonant circuit and the second end of the receiving coil are both connected with the second end of the switching circuit.

In some embodiments of the utility model, the resonant circuit comprises a resonant capacitor.

In some embodiments of the utility model, an on-board charging unit includes: a filter and a voltage conversion circuit; the first end of the filter is connected with the charging interface, and the second end of the filter is connected with the third end of the switching circuit; the first end of the voltage conversion circuit is connected with the first end of the switching circuit, and the second end of the voltage conversion circuit is used for being connected with the battery.

In some embodiments of the present utility model, a voltage conversion circuit includes: a power factor correction (power factor correction, PFC) circuit, an inverter circuit, a transformer and a rectifying circuit which are sequentially connected in series; the alternating-current end of the PFC circuit is used as a first end of the voltage conversion circuit and is connected with the first end of the switching circuit; the direct current end of the rectifying circuit is used as the second end of the voltage converting circuit to be connected with the battery.

In some embodiments of the present utility model, the PFC circuit, the inverter circuit, and the rectifier circuit are all full-bridge circuits.

The charging system according to the embodiment of the utility model comprises a battery and the charging circuit; the charging circuit is used for charging the battery.

The vehicle comprises the charging system.

Additional aspects and advantages of the utility model will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the utility model.

Drawings

Fig. 1 is a schematic structural diagram of a charging system according to an embodiment of the present utility model;

Fig. 2 is a schematic structural diagram of another charging system according to an embodiment of the present utility model;

fig. 3 is a schematic structural view of a charging system according to still another embodiment of the present utility model;

Fig. 4 is a schematic structural view of a charging system according to still another embodiment of the present utility model;

fig. 5 is a schematic structural view of a charging system according to still another embodiment of the present utility model;

Fig. 6 is a schematic structural view of a charging system according to still another embodiment of the present utility model;

Fig. 7 is a schematic diagram of a voltage conversion circuit according to an embodiment of the present utility model;

Fig. 8 is a schematic diagram of a charging system according to an embodiment of the present utility model.

A charging system 1000; a charging circuit 100; a battery 200;

A switching circuit 10; a wireless charging reception unit 20; a charging interface 30; an in-vehicle charging unit 40; a controller 50;

A resonant circuit 201; a receiving coil L1; a filter 401; a voltage conversion circuit 402, a second PFC circuit 4021, an inverter circuit 4022, a transformer 4023, a rectifier circuit 4024, and a dc bus capacitor Cr;

The first switching tube to the Q1-twelfth switching tube Q12;

ground side circuit 2000, power supply 2001, filter circuit 2002, first PFC circuit 2003, lcc resonant circuit 2004, and transmitting coil L2.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present utility model and should not be construed as limiting the utility model.

The vehicle may include a charging circuit coupled to the battery and a battery, the charging circuit configured to charge the battery. The charging circuit may comprise an OBC or a wireless charging receiver circuit, which complies with the GB/T38775 standard. The OBC is used for charging the battery in the conduction charging mode, and the wireless charging receiving end circuit is used for charging the battery in the wireless charging mode. The wireless charging receiving end circuit can comprise a receiving coil, an LCC resonant circuit and a rectifier, and is used for acquiring electric energy from an alternating magnetic field generated by a ground end, so that wireless transmission of the electric energy is realized. But such charging is less flexible.

The embodiment of the utility model provides a vehicle, which comprises a charging system 1000, as shown in fig. 1, wherein the charging system 1000 comprises a charging circuit 100 and a battery 200, the charging circuit 100 is connected with the battery 200, and the charging circuit 100 is used for charging the battery 200.

According to the charging circuit 100 of the embodiment of the present utility model, as shown in fig. 2 and 3, the charging circuit 100 includes: switching circuit 10, wireless charge receiving unit 20, charging interface 30 and on-board charging unit 40. The wireless charging receiving unit 20 is compatible with the ground terminal circuit given by national standard GB/T38775.

The first end 1 of the switching circuit 10 is connected with the first end of the vehicle-mounted charging unit 40, the second end 2 of the switching circuit 10 is connected with the wireless charging receiving unit 20, the third end 3 of the switching circuit 10 is connected with the second end of the vehicle-mounted charging unit 40, the third end of the vehicle-mounted charging unit 40 is connected with the charging interface 30, and the fourth end of the vehicle-mounted charging unit 40 is suitable for being connected with the battery 200.

The operating modes of the charging circuit 100 may include a wireless charging mode and a conductive charging mode. In the wireless charging mode, the first terminal 1 and the second terminal 2 of the switching circuit 10 are electrically connected to allow the in-vehicle charging unit 40 to be connected to the wireless charging receiving unit 20. In the conductive charging mode, the first terminal 1 and the third terminal 3 of the switching circuit 10 are electrically connected to enable the in-vehicle charging unit 40 to access the charging interface 30.

As shown in fig. 2, the second terminal 2 of the switching circuit 10 is connected to the wireless charging receiving unit 20, and in the case where the first terminal 1 and the second terminal 2 of the switching circuit 10 are electrically connected, the wireless charging receiving unit 20 may transmit the acquired voltage from the alternating magnetic field generated by the ground terminal circuit 2000 to the in-vehicle charging unit 40, and the in-vehicle charging unit 40 is configured to convert the voltage and transmit the converted voltage to the battery 200, thereby implementing wireless charging.

In the case where the charging interface 30 is connected to an external power source, the external power source may be, for example, a power source supplied from a power grid, or a power source supplied from a generator. As shown in fig. 3, the third terminal 3 of the switching circuit 10 is connected to the second terminal of the vehicle-mounted charging unit 40, the third terminal of the vehicle-mounted charging unit 40 is connected to the charging interface 30, and in the case where the first terminal 1 and the third terminal 3 of the switching circuit 10 are electrically connected, the vehicle-mounted charging unit 40 is configured to convert a voltage supplied from an external power source and transmit the converted voltage to the battery 200, thereby realizing conductive charging.

In the case where the charging circuit 100 is provided with the in-vehicle charging unit 40, by newly adding the switching circuit 10 and the wireless charging reception unit 20 to the charging circuit 100, the switching circuit 10, the wireless charging reception unit 20, and the in-vehicle charging unit 40 collectively realize the wireless charging function with the first terminal 1 and the second terminal 2 of the switching circuit 10 electrically connected.

In the embodiment of the utility model, the switching circuit 10 and the wireless charging receiving unit 20 are newly added in the charging circuit 100, and the wireless charging function can be realized by multiplexing the original vehicle-mounted charging unit 40 in the charging circuit 100.

In summary, the present utility model provides a charging circuit, in which a first end of a switching circuit is connected to a first end of a vehicle-mounted charging unit, a second end of the switching circuit is connected to a wireless charging receiving unit, a third end of the switching circuit is connected to a second end of the vehicle-mounted charging unit, a third end of the vehicle-mounted charging unit is connected to a charging interface, and a fourth end of the vehicle-mounted charging unit is adapted to be connected to a battery. Through newly increasing switching circuit and wireless receiving cell that charges in charging circuit, under wireless charging mode, switching circuit's first end is connected with the second end electricity, and from this wireless receiving cell that charges and on-vehicle machine charge for the battery, under conduction charging mode, switching circuit's first end is connected with the third end electricity, from this on-vehicle machine charges for the battery, compares in the correlation technique, has improved the flexibility of charging.

In some embodiments of the present utility model, the switching circuit 10 may be a switch, which may include a relay or a Metal Oxide Semiconductor Field Effect Transistor (MOSFET). Referring to fig. 4, 5 and 6, the switching circuit 10 may be a double pole double throw relay. In the wireless charging mode, the first terminal 1 and the second terminal 2 of the relay are electrically connected, and the first terminal 1 and the third terminal 3 of the relay are disconnected, whereby the wireless charging receiving unit 20 is connected to the in-vehicle charging unit 40 through the relay, thereby realizing wireless charging of the battery 200.

In the conductive charging mode, the first terminal 1 of the relay is electrically connected to the third terminal 3, and the first terminal 1 of the relay is disconnected from the second terminal 2, whereby the charging interface 30 is connected to the in-vehicle charging unit 40 through the relay, thereby achieving conductive charging of the battery 200.

In some embodiments of the present utility model, as shown in fig. 4, the in-vehicle charging unit 40 may include: a filter 401 and a voltage conversion circuit 402, a first terminal of the filter 401 is connected to the charging interface 30, and a second terminal of the filter 401 is connected to the third terminal 3 of the switching circuit 10. A first terminal of the voltage conversion circuit 402 is connected to the first terminal 1 of the switching circuit 10, and a second terminal of the voltage conversion circuit 402 is used for connection to the battery 200.

The filter 401 is used to filter out interference signals, and reduce interference coupling between the charging circuit 100 and an external power supply. The voltage conversion circuit 402 is configured to convert the received voltage and transmit the converted voltage to the battery 200, thereby charging the battery 200.

In the conductive charging mode, the first terminal of the filter 401 may be connected to an external power source through the charging interface 30, the second terminal of the filter 401 is connected to the third terminal 3 of the switching circuit 10, and the first terminal 1 of the switching circuit 10 is connected to the voltage conversion circuit 402. In the case where the first terminal 1 and the third terminal 3 of the switching circuit 10 are electrically connected, the voltage conversion circuit 402 is configured to convert the voltage provided by the filter 401 and transmit the converted voltage to the battery 200, so that the battery 200 can be charged through the filter 401, the switching circuit 10 and the voltage conversion circuit 402.

In the wireless charging mode, the first terminal 1 and the second terminal 2 of the switching circuit 10 are electrically connected, and the voltage conversion circuit 402 is configured to convert the voltage provided by the wireless charging receiving unit 20 and transmit the converted voltage to the battery 200.

In some embodiments of the present utility model, as shown in fig. 5, the wireless charging receiving unit 20 may include: the resonant circuit 201 and the receiving coil L1, wherein a first end of the resonant circuit 201 is connected to a first end of the receiving coil L1, and a second end of the resonant circuit 201 and a second end of the receiving coil L1 are both connected to a second end 2 of the switching circuit 10.

The receiving coil L1 is used for inducing a high-frequency ac voltage in a high-frequency magnetic field generated by the transmitting coil L2 in the ground-side circuit 2000, and the resonant circuit 201 is used for counteracting the inductive reactance of the receiving coil L1, so as to maximize the amplitude of the high-frequency ac voltage provided to the ac port of the vehicle-mounted charging unit 40. The frequency of the induced voltage of the receiving coil L1 may be 85 kilohertz (kHz).

Referring to fig. 5, the ground side circuit 2000 may include: a power supply 2001, a filter circuit 2002, a first PFC circuit 2003, an LCC-type resonance circuit 2004, and a transmitting coil L2, which are connected in this order.

In some embodiments of the present utility model, as shown in fig. 5 and 6, the resonant circuit 201 and the receiving coil L1 are connected in series, and the resonant circuit 201 may include a resonant capacitor. The first end of the resonance capacitor is connected to the first end of the receiving coil L1, and the second end of the resonance capacitor and the second end of the receiving coil L1 are both connected to the second end 2 of the switching circuit 10.

On the premise that the wireless charging receiving unit is compatible with a ground terminal circuit given by national standard GB/T38775, the resonant circuit provided by the embodiment of the utility model only comprises one resonant capacitor, compared with an LCC type resonant circuit provided in the related art, one inductor and one resonant capacitor are omitted, the minimization of the number of components is realized, and the cost is reduced, the power density is improved, and the energy conversion efficiency is improved.

In some embodiments of the present utility model, as shown in fig. 5 and 6, the voltage conversion circuit 402 may include: a second PFC circuit 4021, an inverter circuit 4022, a transformer 4023, and a rectifier circuit 4024 are sequentially connected in series. The ac terminal of the second PFC circuit 4021 is connected to the first terminal 1 of the switching circuit 10 as a first terminal of the voltage conversion circuit 402, and the dc terminal of the rectifying circuit 4024 is connected to the battery 200 as a second terminal of the voltage conversion circuit 402.

The primary winding of the transformer 4023 is connected to the ac terminal of the inverter circuit 4022, and the secondary winding of the transformer 4023 is connected to the ac terminal of the rectifier circuit 4024.

In the wireless charging mode, the second PFC circuit 4021 is configured to rectify an ac voltage supplied from the wireless charging receiving unit 20 to obtain a dc voltage, and transmit the dc voltage to an input side of the inverter circuit 4022.

In the conduction charging mode, the external power supply supplies an alternating current, and the second PFC circuit 4021 is configured to convert the alternating current voltage transmitted from the filter 401 into a direct current voltage and perform power factor correction, and transmit the corrected direct current voltage to the input side of the inverter circuit 4022. The second PFC circuit 4021 can improve the power factor of the external ac power supply side.

In the wireless charging mode and the conductive charging mode, the inverter circuit 4022 may convert the direct-current voltage transmitted by the second PFC circuit 4021 into a high-frequency alternating-current voltage, and the transformer 4023 is used to realize electrical isolation. The rectifier circuit 4024 may convert the high-frequency alternating-current voltage transmitted from the transformer 4023 into a direct-current voltage and transmit the direct-current voltage to the battery 200.

In the embodiment of the present utility model, the switching circuit 10 and the wireless charging receiving unit 20 are newly added to the charging circuit 100, and the wireless charging function can be realized by multiplexing most of the devices (i.e., the second PFC circuit 4021, the inverter circuit 4022, the transformer 4023 and the rectifying circuit 4024) in the original vehicle-mounted charging unit 40 in the charging circuit 100. Because more devices are not needed to be newly added in the charging circuit, the volume and the weight of the charging circuit are reduced, and the complexity and the cost for realizing the wireless charging function of the charging circuit are reduced.

In some embodiments of the present utility model, as shown in fig. 7, the second PFC circuit 4021, the inverter circuit 4022, and the rectifier circuit 4024 are all full-bridge circuits, and the inverter circuit 4022, the transformer 4023, and the rectifier circuit 4024 together form a dual active bridge (dual active bridge, DAB) topology. Referring to fig. 7, the second PFC circuit 4021 includes four switching transistors Q1, Q2, Q3, Q4 and a dc bus capacitor Cr, where Q1 and Q2 are located on one leg of the second PFC circuit 4021, Q3 and Q4 are located on the other leg of the second PFC circuit 4021, and the dc bus capacitor Cr is connected in parallel with the leg of the second PFC circuit 4021.

The inverter circuit 4022 includes four switching transistors Q5, Q6, Q7, Q8, where Q5 and Q6 are located on one leg of the inverter circuit 4022 and Q7 and Q8 are located on the other leg of the inverter circuit 4022. The rectifying circuit 4024 includes four switching transistors Q9, Q10, Q11, Q12, where Q9 and Q10 are located on one leg of the rectifying circuit 4024 and Q11 and Q12 are located on the other leg of the rectifying circuit 4024. The switching tubes of Q1-Q12 can be MOS tubes.

In some embodiments of the present utility model, referring to fig. 8, the charging circuit may further include: a controller 50 for controlling the first terminal 1 and the third terminal 3 of the switching circuit 10 to be connected and controlling the switching tube driving signal in the vehicle-mounted charging unit 40 to realize charging current adjustment in the conductive charging mode; in the wireless charging mode, the first terminal 1 and the second terminal 2 of the switching circuit 10 are controlled to be connected, and the driving signal of the switching tube in the vehicle-mounted charging unit 40 is controlled to realize the optimization of the charging system efficiency and the adjustment of the charging current.

In some embodiments of the present utility model, as shown in fig. 8, the ground side circuit 2000 may communicate with the controller 50 in wireless fidelity (WIRELESS FIDELITY, wi-Fi), and the process of the controller 50 adjusting the charging current value of the battery 200 and optimizing the system efficiency may include the following steps:

A1, acquiring a current value I _TX of the transmitting coil L2, an input power P _in and an output power P _out of the charging circuit.

The controller 50 may periodically acquire the current value I _TX of the transmitting coil L2, the input power P _in, and the output power P _out of the charging circuit. Since the ground side and the vehicle side can perform Wi-Fi communication, the controller 50 can acquire the current value I _TX and the input power P _in of the transmitting coil L2 through Wi-Fi communication with the ground side.

The controller 50 may also monitor the actual charging current i of the battery in real time and adjust the actual charging current i to be equal to the charging current target value i ^*, wherein the controller 50 may adjust the actual charging current i by controlling the phase shift angle or switching frequency of the inverter circuit 4022. The controller 50 may also directly obtain the output power P _out of the charging circuit.

A2, determining a current target value I _TX ^* of the transmitting coil L2 at the next moment through an efficiency optimizing algorithm based on a current value I _TX of the transmitting coil L2, an input power P _in and an output power P _out.

The controller 50 can determine the current target value I _TX ^* of the transmitting coil L2 at the next time based on the obtained current value I _TX, input power P _in, and output power P _out of the transmitting coil L2, and calculate the current value I _TX, input power P _in, and output power P _out of the transmitting coil L2 as input values of the efficiency optimizing algorithm.

A3, the controller in the ground side circuit 2000 controls the current value I _TX of the transmitting coil L2 to be maintained at the current target value I _TX ^*.

After determining the current target value I _TX ^* at the next time, the controller 50 returns the current target value I _TX ^* to the controller in the ground side circuit 2000 via Wi-Fi, and the controller in the ground side circuit 2000 maintains the current value I _TX of the transmitting coil L2 at the current target value I _TX ^*.

Controlling the current value I _TX of the transmitting coil L2 to be maintained at the current target value I _TX ^* means that the current real I _TX of the transmitting coil L2 is equal to the current target value I _TX ^* within an error tolerance range.

In the embodiment of the utility model, the charging current can be quickly regulated by multiplexing most circuits in the OBC, and a newly added charging current control circuit is not needed in the charging circuit, so that the newly added hardware cost for realizing the wireless charging function can be minimized.

In summary, the present utility model provides a charging circuit, in which a first end of a switching circuit is connected to a first end of a voltage conversion circuit in a vehicle charging unit, a second end of the switching circuit is connected to a wireless charging receiving unit, a third end of the switching circuit is connected to a second end of a filter in the vehicle charging unit, and a second end of the voltage conversion circuit in the vehicle charging unit is adapted to be connected to a battery of a vehicle. Through newly increasing switching circuit and wireless receiving cell that charges in charging circuit, under wireless charging mode, switching circuit's first end is connected with the second end electricity, and from this wireless receiving cell that charges and on-vehicle machine charge for the battery, under conduction charging mode, switching circuit's first end is connected with the third end electricity, from this on-vehicle machine charges for the battery, compares in the correlation technique, has improved the flexibility of charging.

It is to be understood that portions of the present utility model may be implemented in hardware, software, firmware, or a combination thereof. In the above-described embodiments, the various steps or methods may be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, may be implemented using any one or combination of the following techniques, as is well known in the art: discrete logic circuits having logic gates for implementing logic functions on data signals, application specific integrated circuits having suitable combinational logic gates, programmable Gate Arrays (PGAs), field Programmable Gate Arrays (FPGAs), and the like.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Furthermore, the terms "first," "second," and the like, as used in embodiments of the present utility model, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or as implying any particular number of features in the present embodiment. Thus, a feature of an embodiment of the utility model that is defined by terms such as "first," "second," etc., may explicitly or implicitly indicate that at least one such feature is included in the embodiment. In the description of the present utility model, the word "plurality" means at least two or more, for example, two, three, four, etc., unless explicitly defined otherwise in the embodiments.

In the present utility model, unless explicitly stated or limited otherwise in the examples, the terms "mounted," "connected," and "fixed" as used in the examples should be interpreted broadly, e.g., the connection may be a fixed connection, may be a removable connection, or may be integral, and it may be understood that the connection may also be a mechanical connection, an electrical connection, etc.; of course, it may be directly connected, or indirectly connected through an intermediate medium, or may be in communication with each other, or in interaction with each other. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to specific embodiments.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the utility model.

Claims (9)

1. A charging circuit adapted to charge a battery of a vehicle, the charging circuit comprising: the wireless charging system comprises a switching circuit, a wireless charging receiving unit, a charging interface and a vehicle-mounted charging unit;

The first end of the switching circuit is connected with the first end of the vehicle-mounted charging unit, the second end of the switching circuit is connected with the wireless charging receiving unit, the third end of the switching circuit is connected with the second end of the vehicle-mounted charging unit, the third end of the vehicle-mounted charging unit is connected with the charging interface, the fourth end of the vehicle-mounted charging unit is suitable for being connected with a battery of the vehicle, and in a wireless charging mode, the first end of the switching circuit is electrically connected with the second end; in the conductive charging mode, the first end of the switching circuit is electrically connected to the third end.

2. The charging circuit of claim 1, wherein the switching circuit comprises a relay.

3. The charging circuit of claim 1, wherein the wireless charging receiving unit comprises: a resonant circuit and a receiving coil;

The first end of the resonant circuit is connected with the first end of the receiving coil, and the second end of the resonant circuit and the second end of the receiving coil are both connected with the second end of the switching circuit.

4. A charging circuit according to claim 3, wherein the resonant circuit comprises a resonant capacitor.

5. The charging circuit according to any one of claims 1 to 4, wherein the in-vehicle charging unit includes: a filter and a voltage conversion circuit;

the first end of the filter is connected with the charging interface, and the second end of the filter is connected with the third end of the switching circuit;

the first end of the voltage conversion circuit is connected with the first end of the switching circuit, and the second end of the voltage conversion circuit is used for being connected with the battery.

6. The charging circuit of claim 5, wherein the voltage conversion circuit comprises: the power factor correction PFC circuit, the inverter circuit, the transformer and the rectifying circuit are sequentially connected in series;

The alternating-current end of the PFC circuit is used as the first end of the voltage conversion circuit and is connected with the first end of the switching circuit;

The direct current end of the rectifying circuit is used as the second end of the voltage conversion circuit to be connected with the battery.

7. The charging circuit of claim 6, wherein the PFC circuit, the inverter circuit, and the rectifier circuit are all full-bridge circuits.

8. A charging system comprising a battery and a charging circuit as claimed in any one of claims 1 to 7 for charging the battery.

9. A vehicle characterized in that it comprises the charging system of claim 8.