CN112583061B

CN112583061B - Vehicle-mounted charging system and vehicle with same

Info

Publication number: CN112583061B
Application number: CN201910936706.1A
Authority: CN
Inventors: 许兴发; 吴昊; 刘宇; 杨柳
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2019-09-29
Filing date: 2019-09-29
Publication date: 2023-03-24
Anticipated expiration: 2039-09-29
Also published as: CN112583061A

Abstract

The invention discloses a vehicle-mounted charging system and a vehicle with the same, wherein the vehicle-mounted charging system comprises a first resonant circuit module, a second resonant circuit module, a first rectifying circuit module, a second rectifying circuit module and a control module, wherein the first resonant circuit module is used for converting an input electric signal; the second resonance circuit module is used for converting the input electric signal; the first rectifying circuit module and the second rectifying circuit module are used for rectifying the input electric signal; the control module is used for controlling the first resonant circuit module in a first half period of power supply, or controlling the second resonant circuit module in a second half period of power supply, or respectively controlling the second conversion unit, the first rectification circuit module, the fourth conversion unit and the second rectification circuit module according to a control time sequence of charging the low-voltage battery pack by the high-voltage battery pack. The system and the vehicle can reduce cost and improve stability.

Description

Vehicle-mounted charging system and vehicle with same

Technical Field

The invention relates to the technical field of vehicles, in particular to a vehicle-mounted charging system and a vehicle with the same.

Background

Fig. 1 is a circuit diagram of a vehicle charging system in the related art, in which one end of the system is connected to a power grid, and the other end of the system is connected to a battery pack, and the system includes a Part1 'and Part2' two-stage circuit. During forward charging, part1' realizes alternating current-direct current conversion and power factor correction, and outputs direct current voltage. Part2' is a dc-dc converter that outputs a suitable voltage to charge the battery pack. For the system, in order to provide stable input direct current voltage for the later stage Part2', a large-capacity electrolytic capacitor C1' is needed between the Part1' and the Part2', so that the volume and the cost of the system are increased, and the electrolytic capacitor C1' has the problems of service life and shock resistance and is unfavorable for the reliability of the system.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, an object of the present invention is to provide an onboard charging system that does not require a large-capacity electrolytic capacitor, reduces the system size, reduces the cost, and improves the system stability.

The invention further provides a vehicle adopting the vehicle-mounted charging system.

In order to solve the above problem, an in-vehicle charging system according to an embodiment of a first aspect of the present invention includes: the first resonant circuit module is used for converting an input electric signal and comprises a first conversion unit, a first transformer and a second conversion unit, wherein the first conversion unit comprises a third switching tube and a fourth switching tube, the first end of the third switching tube is connected with the first end of the electric unit, and the second end of the third switching tube is connected with the first end of the fourth switching tube; the second resonant circuit module is used for converting an input electric signal, and comprises a third conversion unit, a second transformer and a fourth conversion unit, wherein the third conversion unit comprises a fifth switching tube and a sixth switching tube, the first end of the fifth switching tube is connected with the second end of the electric unit, the second end of the fifth switching tube is connected with the first end of the sixth switching tube, and the second end of the sixth switching tube is connected with the second end of the fourth switching tube; the first end of the first rectifying circuit module is connected with the secondary side of the first transformer and used for rectifying an input electric signal; a second rectifier circuit module, a first end of which is connected to a secondary side of the second transformer, for rectifying an input electrical signal; and the control module is used for outputting the first gating control signal during a first half period of power supply, and respectively controlling the first resonant circuit module and the first rectifying circuit module according to a time sequence signal of the first half period of power supply, or outputting the second gating control signal during a second half period of power supply, and respectively controlling the second resonant circuit module and the second rectifying circuit module according to a time sequence signal of the second half period of power supply, or respectively controlling the second conversion unit, the first rectifying circuit module, the fourth conversion unit and the second rectifying circuit module according to a control time sequence of charging a low-voltage battery pack by a high-voltage battery pack.

According to the vehicle-mounted charging system provided by the embodiment of the invention, two resonant circuit modules are arranged, the control module is controlled according to the power supply periodic signal to gate the first resonant circuit module or the second resonant circuit module, so that the signals output to the post-stage circuit by the resonant circuit module and the rectifying circuit module are steamed bread waves, and therefore, filtering is not required by a large-capacity electrolytic capacitor, only a small-capacity capacitor such as a thin-film capacitor is required to be used, the cost and the volume of the electrolytic capacitor part are reduced, the reliability and the service life of the system are improved, charging of a low-voltage battery pack can be simultaneously realized by the first rectifying circuit module and the second rectifying circuit module, gating can be realized by series control of switching tubes in the resonant circuit, independent gating circuits are not required to be arranged, the number of the switching tubes is reduced, and the cost is further reduced.

In order to solve the above problem, a vehicle according to an embodiment of a second aspect of the present invention includes a high-voltage battery pack, a low-voltage battery pack, and the vehicle-mounted charging system.

According to the vehicle provided by the embodiment of the invention, by adopting the vehicle-mounted charging system provided by the embodiment of the invention, the cost can be reduced, the reliability is improved, the anti-seismic grade is improved, and the charging of the low-voltage battery pack can be realized at the same time.

Additional aspects and advantages of the invention 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 invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a circuit diagram of a bidirectional vehicle-mounted charger in the related art;

FIG. 2 is a functional block diagram of an in-vehicle charging system according to one embodiment of the present invention;

FIG. 3 is a schematic diagram of a resonant circuit output electrical signal waveform according to one embodiment of the present invention;

fig. 4 is a functional block diagram of an in-vehicle charging system according to another embodiment of the present invention;

fig. 5 is a functional block diagram of an in-vehicle charging system according to another embodiment of the present invention;

fig. 6 is a circuit diagram of an in-vehicle charging system according to an embodiment of the invention;

fig. 7 is a circuit diagram of an in-vehicle charging system according to another embodiment of the invention;

FIG. 8 is a block diagram of a vehicle according to one embodiment of the present invention.

Detailed Description

Embodiments of the present invention will be described in detail below, the embodiments described with reference to the drawings being illustrative, and the embodiments of the present invention will be described in detail below.

An in-vehicle charging system according to an embodiment of the invention is described below with reference to fig. 2 to 7.

Fig. 2 is a block diagram of an in-vehicle charging system according to an embodiment of the present invention, and as shown in fig. 2, an in-vehicle charging system 100 of an embodiment of the present invention includes a first resonant circuit module 10, a second resonant circuit module 20, a first rectifier circuit module 80, a second rectifier circuit module 81, and a control module 50.

The first resonant circuit module 10 is configured to perform conversion processing on an input electrical signal, and the first resonant circuit module 10 includes a first conversion unit 11, a first transformer T1, and a second conversion unit 12, where the first conversion unit 11 may be configured to perform conversion between an ac positive half cycle and an ac, the second conversion unit 12 may implement conversion between an ac and a dc, and the first transformer T1 plays roles in signal isolation, voltage transformation, and transmission. The first conversion unit 11 includes a third switching tube Q3 and a fourth switching tube Q4, a first end of the third switching tube Q3 is connected to a first end of the electric unit 60, and a second end of the third switching tube Q3 is connected to a first end of the fourth switching tube Q4.

The second resonant circuit module 20 is configured to perform conversion processing on an input electrical signal, and the second resonant circuit module 20 includes a third conversion unit 21, a second transformer T2, and a fourth conversion unit 22, where the third conversion unit 21 may be configured to perform conversion between an ac negative half cycle and an ac, the fourth conversion unit 22 may implement conversion between an ac and a dc, and the second transformer T2 plays roles in signal isolation, voltage transformation, and transmission. The third converting unit 21 includes a fifth switching tube Q5 and a sixth switching tube Q6, a first end of the fifth switching tube Q5 is connected to the second end of the electric unit 60, a second end of the fifth switching tube Q5 is connected to a first end of the sixth switching tube Q6, and a second end of the sixth switching tube Q6 is connected to a second end of the fourth switching tube Q4. In the embodiment of the present invention, the electrical unit may be a power grid or an electrical load, that is, when the electrical unit is the power grid, the charging operation is performed, or when the electrical unit is the electrical load, the discharging operation of the power battery is performed.

The first end of the first rectifier circuit module 80 is connected to the secondary side of the first transformer T1 for rectifying the input electrical signal, and then the rectified electrical signal can be provided to a subsequent circuit, so as to charge the low-voltage battery pack. The first end of the second rectifier circuit module 81 is connected to the secondary side of the second transformer T2 for rectifying the input electrical signal, and then the rectified electrical signal can be provided to a subsequent circuit, so as to charge the low-voltage battery pack.

The control module 50 is configured to control the fifth switching tube Q5 and the sixth switching tube Q6 to remain on during a first half period of power supply, and respectively control the first resonant circuit module 10 and the first rectifying circuit module 80 according to a timing signal of the first half period of power supply, or control the third switching tube Q3 and the fourth switching tube Q4 to remain on during a second half period of power supply, and control the second resonant circuit module 20 and the second rectifying circuit module 81 according to a timing signal of the second half period of power supply. Or, when the high-voltage battery pack charges the low-voltage battery pack, the control module 50 is configured to control the second conversion unit 12, the first rectification circuit module 80, the fourth conversion unit 22, and the second rectification circuit module 81 according to a control timing sequence for charging the low-voltage battery pack by the high-voltage battery pack.

Specifically, when charging is performed, the electrical unit 60 may be a power grid, the control module 50 detects cycle information of an alternating current output by the power grid, and controls the fifth switching tube Q5 and the sixth switching tube Q6 to be kept on when a first half cycle of power supply, such as a positive half cycle, is performed, at this time, the first end of the first resonant circuit module 10 is connected to the first end of the power grid, the second end of the first resonant circuit module 10 is connected to the second end of the power grid, the power grid supplies power to the first resonant circuit module 10, that is, the first resonant circuit module 10 is gated when the power grid outputs the positive half cycle, the control module 50 controls the first resonant circuit module 10 according to a timing signal of the first half cycle of power supply, and the first resonant circuit module 10 converts an alternating current signal of the positive half cycle of the power grid into a direct current electrical signal, and inputs the direct current electrical signal to a subsequent circuit to charge the high-voltage battery pack. And the first rectification circuit module 81 rectifies the alternating current signal transmitted by the secondary coil of the first transformer T1, and then the rectified alternating current signal can be provided to the low-voltage battery pack to charge the low-voltage battery pack

Similarly, when the control module 50 detects a second half period of the power supply, for example, a negative half period of the electrical signal, the third switching tube Q3 and the fourth switching tube Q4 are controlled to remain conductive, and at this time, the first terminal of the second resonant circuit module 20 is connected to the second terminal of the power grid, the second terminal of the second resonant circuit module 20 is connected to the first terminal of the power grid, the power grid supplies power to the second resonant circuit module 20, that is, the second resonant circuit module 20 is gated when the power grid outputs the negative half period, and the control module 50 controls the second resonant circuit module 20 according to the timing signal of the second half period of the power supply, and the second resonant circuit module 20 converts the ac signal of the negative half period of the power grid into a dc electrical signal, which is input to the rear stage circuit to charge the high voltage battery pack. And the second rectifier circuit module 81 rectifies the ac signal transmitted by the secondary coil of the second transformer T2, and then can provide the rectified ac signal to the low-voltage battery pack at the subsequent stage, thereby implementing charging of the low-voltage battery pack.

As shown in fig. 3, the electrical signal provided by the power grid 50 is as shown in (a) of fig. 3, and during the positive half-cycle, the control module 50 controls the gating circuit module 30 to conduct at the corresponding switching tube to gate the first resonant circuit module 10, the electrical signal input to the first resonant circuit module 10 is as shown in (b) of fig. 3, and the electrical signal output by the first resonant circuit module 10 is as shown in (d) of fig. 3. And, during the negative half cycle, the control module 50 controls the corresponding switch in the gating circuit module 30 to be turned on to gate the second resonant circuit module 20, the input electrical signal of the second resonant circuit module 20 is shown in (c) in fig. 3, the output electrical signal of the second resonant circuit module 20 is shown in (e) in fig. 3, and the waveform of the electrical signal output by the first resonant circuit module 10 and the second resonant circuit module 20 and combined by the output electrical signals of the second resonant circuit module 20, i.e., the waveform of the electrical signal provided to the subsequent circuit is shown in (f) in fig. 3, i.e., the electrical signal provided to the subsequent circuit is a steamed bread wave, and similarly, the electrical signals provided to the subsequent circuit by the first rectifier circuit module 80 and the second rectifier circuit module 81 are also a steamed bread wave.

In addition, in the embodiment of the present application, the gating circuit may be omitted, and the control module 50 controls the third switching tube Q3, the fourth switching tube Q4, the fifth switching tube Q5, and the sixth switching tube Q6 according to the power supply period signal to gate the resonant circuit, so that circuit devices may be saved, and the cost may be reduced.

And, when the high voltage battery pack is discharged, when a positive half cycle is output, the first resonance circuit module 10 is gated, and the direct current output from the high voltage battery pack is converted into an alternating current signal of a positive half cycle by the first resonance circuit module 10 and supplied to the electrical unit 60, for example, an electrical load. When the negative half cycle is output, the second resonant circuit module 20 is gated, and the direct current output by the high-voltage battery pack is converted into an alternating current signal with the negative half cycle through the second resonant circuit module 20 and is provided to the electric load, so that the discharge mode of the high-voltage battery pack is realized.

And, in the embodiment of the present invention, the charging of the high-voltage battery pack to the low-voltage battery pack can also be realized by combining the first resonant circuit 10 and the second resonant circuit 20, and the first rectifier circuit module 80 and the second rectifier circuit module 81. Specifically, the control module 50 controls the second conversion unit 12, the first rectifier circuit module 80, and the fourth conversion unit 22 and the second rectifier circuit module 81, respectively, according to the control timing of the high-voltage battery pack charging the low-voltage battery pack. The high voltage direct current provided by the high voltage battery pack can be converted into alternating current through the second conversion unit 12 and the fourth conversion unit 22 respectively, and transmitted to the first transformer T1 and the second transformer T2, and provided to the first rectification circuit module 80 through the secondary coil of the first transformer T1, and provided to the second rectification circuit module 80 through the secondary coil of the second transformer T2, the control module 50 controls the switching tubes of the first rectification circuit module 80 and the second rectification circuit module 81, so as to rectify and convert the alternating current into direct current to provide the second direct current conversion circuit module 41, so as to provide the low voltage battery pack, and thus, the charging of the low voltage battery pack by the high voltage battery pack is realized.

According to the vehicle-mounted charging system 100 provided by the embodiment of the invention, by arranging the two resonant circuits and the two rectifier circuit modules, the control module 50 respectively controls the first resonant circuit module 10 and the second resonant circuit module 20 according to the time sequence of the corresponding power supply period, and controls the first rectifier circuit module 80 and the second rectifier circuit module 81 according to the power supply period, so that the direct current signals provided by the resonant circuit modules and the rectifier circuit modules to the subsequent circuit are steamed bread waves, a large-capacity filter device is not needed, a small-capacity filter device is only needed, the volume and the cost of the system can be reduced, the problems of electrolytic capacitor service life and shock resistance are not needed to be considered, the stability of the charging system is favorably provided, and the charging of low-voltage battery packs can be simultaneously realized through the first rectifier circuit module 80 and the second rectifier circuit module 82, the gating can be realized through the series control of the switch tubes in the resonant circuit, a separate gating circuit is not needed to be arranged, the number of the switch tubes is reduced, and the cost is reduced.

In some embodiments, for the vehicle-mounted charging system provided with the gating circuit module, gating is realized through independent control of the switching tube in the gating circuit module, so that larger conduction loss is generated, and therefore, the system provided by the embodiment of the invention is improved on the basis.

Further, as shown in fig. 4, the vehicle-mounted charging system 100 according to the embodiment of the invention may further include a gating circuit module 30, where the gating circuit module 30 includes a first switching tube Q1 and a second switching tube Q2. A first end of the first switching tube Q1 is connected to a first end of the electrical unit 60, a second end of the first switching tube Q1 is connected to a second end of the fourth switching tube Q4 and a second end of the sixth switching tube Q6, respectively, a first end of the second switching tube Q2 is connected to a second end of the electrical unit 60, and a second end of the second switching tube Q2 is connected to a second end of the fourth switching tube Q4 and a second end of the sixth switching tube Q6, respectively; the control module 50 is further configured to, during a first half cycle of power supply, control the first switching tube Q1 to turn off, control the second switching tube Q2, the fifth switching tube Q5, and the sixth switching tube Q6 to turn on, and control the first resonant circuit module 10 and the first rectifier circuit module 80 according to a timing signal of the first half cycle of power supply; or, during the second half period of power supply, the second switching tube Q2 is controlled to be turned off, the first switching tube Q1, the third switching tube Q3 and the fourth switching tube Q4 are controlled to be turned on, and the second resonant circuit module 10 and the second rectifying circuit module 81 are controlled according to the timing sequence signal of the second half period of power supply, or the control module 50 is configured to respectively control the second conversion unit 12, the first rectifying circuit module 80, the fourth conversion unit 22 and the second rectifying circuit module 81 according to the control timing sequence of the high-voltage battery pack for charging the low-voltage battery pack.

Specifically, referring to fig. 4, the switching timing sequence of the control module 50 for the gating circuit module 30 is that, when the power grid positive half-cycle signal is, the control module 50 controls the fifth switching tube Q5 and the sixth switching tube Q6 to be kept on, and controls the first switching tube Q1 to be turned off, and controls the second switching tube Q2 to be turned on, that is, the fifth switching tube Q5 and the sixth switching tube Q6 are connected in series and then connected in parallel with the second switching tube Q2, so that the second end of the first resonant circuit module 10 can be connected with the power grid, and gating of the first resonant circuit module 10 is realized, compared with the case of independently controlling the second switching tube Q2 to be turned on, the resistance of the second switching tube Q2 is greater than the resistances of the fifth switching tube Q5 and the sixth switching tube Q6 connected in series and connected in parallel with the second switching tube Q2, so that the conduction loss is reduced. Similarly, during the negative half cycle of the power grid, the control module 50 controls the third switching tube Q3 and the fourth switching tube Q4 to be kept on, controls the first switching tube Q1 to be turned on, and controls the second switching tube Q2 to be turned off, so that the second end of the second resonant circuit module 20 is connected with the first end of the power grid, the gating of the second resonant circuit module 20 is realized, and the conduction loss can be reduced.

Further, as shown in fig. 5, which is a block diagram of an in-vehicle charging system according to another embodiment of the present invention, as shown in fig. 5, the in-vehicle charging system 100 further includes a first dc conversion circuit module 40 and a second dc conversion circuit module 41, where the first dc conversion circuit module 40 is configured to perform dc conversion on an input electrical signal, for example, reduce a dc voltage or boost a dc voltage, and implement power factor correction. In some embodiments, the first dc conversion circuit module 40 may adopt a BOOST circuit or a BUCK circuit. The first dc conversion circuit module 40 is respectively connected to the second conversion unit 12, the fourth conversion unit 22, and the high-voltage battery pack 70, and is configured to perform dc-dc conversion on the input electrical signal. The second dc conversion circuit module 41 is connected to the first rectifier circuit module 80, the second rectifier circuit module 81, and the low-voltage battery pack 71, respectively, and is configured to perform dc-dc conversion on the input electrical signal, so as to convert the input dc signal into an electrical signal required by the low-voltage battery pack 71, and charge the low-voltage battery pack 71.

Specifically, during the first half cycle of power supply, the first resonant circuit module 10 outputs a dc signal to the first dc conversion circuit module 40, and transmits a positive half cycle ac signal to the first rectifier circuit module 80 through the secondary coil of the first transformer T1, and the second rectifier circuit module 80 converts an ac signal to a dc signal and transmits the dc signal to the second dc conversion circuit 41, or, during the second half cycle of power supply, the second resonant circuit module 20 outputs a dc signal to the first dc conversion circuit module 40, and transmits a negative half cycle ac signal to the second rectifier circuit module 81 through the secondary coil of the second transformer T2, and the second rectifier circuit module 81 converts an ac signal to a dc signal and transmits the dc signal to the second dc conversion circuit 41. The first dc conversion circuit module 40 converts the input dc electrical signal into an electrical signal required by the high voltage battery pack 70, and transmits the electrical signal to the high voltage battery pack 70, thereby charging the high voltage battery pack 70. And the second dc conversion circuit 41 converts the input electrical signal into an electrical signal required by the low-voltage battery pack 71 and transmits the electrical signal to the low-voltage battery pack 71, thereby implementing charging of the low-voltage battery pack 71.

In the vehicle-mounted charging system 100 according to the embodiment of the invention, the dc conversion circuit module is disposed at the rear, so that the charging voltage or the charging power output to the battery pack can be adjusted by controlling the duty ratio of the dc conversion circuit module, thereby widening the voltage range of the adaptive battery pack, and shortening the charging time of the battery pack and the charging efficiency of the battery pack.

The circuit structure of each module according to the embodiment of the present invention is further described below with reference to the drawings.

Fig. 6 is a circuit diagram of an in-vehicle charging system without a gating circuit module according to an embodiment of the present invention, and as shown in fig. 7, is a circuit diagram of an in-vehicle charging system including a gating circuit module according to an embodiment of the present invention, wherein, as described above, the gating circuit module 30 includes the first switching tube Q1 and the second switching tube Q2, and the control module 40 controls the gating circuit module 30 and the switching tubes that are conducted in series according to the power supply cycle signal, so as to implement the gating of the resonant circuit. As shown in fig. 7, other circuit modules such as the first resonant circuit module 10 and the second resonant circuit module 20, the first dc conversion circuit module 40, and the second dc conversion circuit module 41 have the same circuit configuration as that in fig. 6.

In some embodiments, as shown in fig. 6 or fig. 7, the first resonant circuit module 10 and the second resonant circuit module 20 may employ a symmetrical half-bridge LLC resonant circuit to achieve isolation and voltage regulation, and perform ac-dc conversion on the input electrical signal.

As shown in fig. 6 or 7, the first conversion unit 11 includes a first capacitor C1, a third switching tube Q3, a fourth switching tube Q4, a second capacitor C2, and a third capacitor C3; the second conversion unit 12 includes a ninth switching tube Q9, a tenth switching tube Q10, a fourth capacitor C4 and a fifth capacitor C5.

A first end of the first capacitor C1 is connected to the first end of the electric unit 60, and a second end of the first capacitor C1 is connected to the second end of the fourth switching tube Q4. The first capacitor C1 can filter the input electrical signal, so as to reduce interference of the electrical signal.

The first end of the third switching tube Q3 is connected with the first end of the first capacitor C1, the control end of the third switching tube Q3 is connected with the control module 50, the second end of the third switching tube Q3 is connected with the first end of the fourth switching tube Q4, the second end of the fourth switching tube Q4 is connected with the second end of the first capacitor C1, the control end of the fourth switching tube Q4 is connected with the control module 50, and a first node O1 is arranged between the second end of the third switching tube Q3 and the first end of the fourth switching tube Q4. The first end of the second capacitor C2 is connected to the first end of the third switching tube Q3, the second end of the second capacitor C2 is connected to the first end of the third capacitor C3, the second end of the third capacitor C3 is connected to the second end of the fourth switching tube Q4, and a second node O2 is arranged between the second end of the second capacitor C2 and the first end of the third capacitor C3.

The first transformer T1 includes a first coil W1 and a second coil W2, a first end of the first coil W1 is connected to a first node O1 through a first inductor L1, a second end of the first coil W1 is connected to a second node O2, and a second inductor L2 is connected between the first end of the first coil W1 and the second end of the second coil W2.

A first end of the ninth switching tube Q9 is connected to the first end of the first dc converting circuit module 40, a control end of the ninth switching tube Q9 is connected to the control module 50, a second end of the ninth switching tube Q9 is connected to the first end of the tenth switching tube Q10, a second end of the tenth switching tube Q10 is connected to the second end of the first dc converting circuit module 40, a control end of the tenth switching tube Q10 is connected to the control module 50, a third node O3 is provided between the second end of the ninth switching tube Q9 and the first end of the tenth switching tube Q10, and the third node O3 is connected to the first end of the second coil W2 through the third inductor L3.

A first end of the fourth capacitor C4 is connected to the first end of the ninth switch tube Q9 and the first end of the first dc conversion circuit module 40, a second end of the fourth capacitor C4 is connected to the first end of the fifth capacitor C5, a second end of the fifth capacitor C5 is connected to the second end of the tenth switch tube Q10 and the second end of the first dc conversion circuit module 40, a fourth node O4 is provided between the second end of the fourth capacitor C4 and the first end of the fifth capacitor C5, and the fourth node O4 is connected to the second end of the second coil W2.

Specifically, when the grid voltage is a positive half-cycle during charging of the high-voltage battery pack 70, the control module 50 controls the fifth switching tube Q5 and the sixth switching tube Q6 to be kept on, or, as shown in fig. 7, controls the fifth switching tube Q5, the sixth switching tube Q6 and the second switching tube Q2 to be kept on, and controls the first switching tube Q1 to be turned off, and the first resonant circuit module 10 is turned on; the grid voltage is applied to the first capacitor C1, the control module 50 turns on or off the third switching tube Q3 and the fourth switching tube Q4 at a fixed frequency and a fixed duty ratio, the second capacitor C2 and the third capacitor C3 are charged and discharged, and an alternating voltage is formed between a midpoint of the third switching tube Q3 and the fourth switching tube Q4, namely a first node O1, and a midpoint of the second capacitor C2 and the third capacitor C3, namely a second node O2. After the isolation and voltage transformation of the first transformer T1, the rectifier circuit composed of the ninth switching tube Q9, the tenth switching tube Q10, the fourth capacitor C4 and the fifth capacitor C5 converts the alternating current voltage between the midpoint of the ninth switching tube Q9 and the tenth switching tube Q10, i.e., the third node O3, and the midpoint of the fourth capacitor C4 and the fifth capacitor C5, i.e., the fourth node O4, into the direct current voltage for output, i.e., the voltage provided to the first direct current conversion circuit module 40, by controlling the on or off of the ninth switching tube Q9 and the tenth switching tube Q10 and charging or discharging the fourth capacitor C4 and the fifth capacitor C5, thereby implementing the alternating current-direct current conversion.

As shown in fig. 6 or fig. 7, the first dc conversion circuit module 40 includes a sixth capacitor C6, a seventh switch Q7, an eighth switch Q8, and a seventh capacitor C7.

A first end of the sixth capacitor C6 is connected to the first end of the ninth switching tube Q9 and the first end of the fourth capacitor C4, respectively, and a second end of the sixth capacitor C6 is connected to the second end of the tenth switching tube Q10 and the second end of the fifth capacitor C5, respectively; the sixth capacitor C6 is used for filtering an input dc signal, and in the embodiment of the present invention, the sixth capacitor C6 may be a capacitor device with a smaller capacity, such as a thin film capacitor, without an electrolytic capacitor with a larger capacity.

A first end of a seventh switching tube Q7 is connected with a first end of the high-voltage battery pack 70, a control end of the seventh switching tube Q7 is connected with the control module 50, a second end of the seventh switching tube Q7 is connected with a first end of an eighth switching tube Q8, a second end of the eighth switching tube Q8 is respectively connected with a second end of a sixth capacitor C6 and a second end of the high-voltage battery pack 70, a control end of the eighth switching tube Q8 is connected with the control module 50, a fifth node O5 is arranged between the second end of the seventh switching tube Q7 and the first end of the eighth switching tube Q8, and the fifth node O5 is connected with the first end of the sixth capacitor C6 through a fourth inductor L4; a first end of the seventh capacitor C7 is connected to the first end of the seventh switch Q7 and the first end of the high-voltage battery pack 70, respectively, and a second end of the seventh capacitor C7 is connected to the second end of the eighth switch Q8 and the second end of the battery pack 70, respectively.

In the present embodiment, the first dc conversion circuit module 40 is disposed at the rear, so that the charging voltage or the charging power output to the high voltage battery pack 70 can be adjusted by controlling the duty ratio of the first dc conversion circuit module 40, thereby not only widening the voltage range of the adaptive battery pack, but also shortening the charging time of the battery and the charging efficiency of the high voltage battery pack 70.

As shown in fig. 6 or 7, the third converting unit 21 includes an eighth capacitor C8, a fifth switching tube Q5, a sixth switching tube Q6, a ninth capacitor C9, and a tenth capacitor C10; the fourth conversion unit 22 includes an eleventh switching tube Q11, a twelfth switching tube Q12, an eleventh capacitor C11, and a twelfth capacitor C12.

The first end of the eighth capacitor C8 is connected to the second end of the electric unit 60 and the first end of the fifth switch tube Q5, the control end of the fifth switch tube Q5 is connected to the control module 50, the second end of the eighth capacitor C8 is connected to the second end of the sixth switch tube Q6, the control end of the sixth switch tube Q6 is connected to the control module 50, the second end of the fifth switch tube Q5 is connected to the first end of the sixth switch tube Q6, and a sixth node O6 is arranged between the second end of the fifth switch tube Q5 and the first end of the sixth switch tube Q6.

A first end of the ninth capacitor C9 is connected to the first end of the fifth switch tube Q5, a second end of the ninth capacitor C9 is connected to the first end of the tenth capacitor C10, a second end of the tenth capacitor C10 is connected to the second end of the sixth switch tube Q6, and a seventh node O7 is provided between the second end of the ninth capacitor C9 and the first end of the tenth capacitor C10.

The second transformer T2 includes a fifth coil W5 and a sixth coil W6, a first end of the fifth coil W5 is connected to a sixth node O4 through a fifth inductor L5, a second end of the fifth coil W5 is connected to a seventh node O7, and a sixth inductor L6 is connected between the first end of the fifth coil W5 and the second end of the fifth coil W5.

A first end of the eleventh switch tube Q10 is connected to a first end of the sixth capacitor C6, a control end of the eleventh switch tube Q11 is connected to the control module 50, a second end of the eleventh switch tube Q11 is connected to a first end of the twelfth switch tube Q12,

a second end of the twelfth switching tube Q12 is connected to a second end of the sixth capacitor C6, a control end of the twelfth switching tube Q12 is connected to the control module 50, an eighth node O8 is arranged between the second end of the eleventh switching tube Q11 and the first end of the twelfth switching tube Q12, and the eighth node O8 is connected to the first end of the sixth coil W6 through the seventh inductor L7.

A first end of the eleventh capacitor C11 is connected to a first end of the eleventh switch Q11, a second end of the eleventh capacitor C11 is connected to a first end of the twelfth capacitor C12, a second end of the twelfth capacitor C12 is connected to a second end of the twelfth switch Q12, a ninth node O9 is disposed between the second end of the eleventh capacitor C11 and the first end of the twelfth capacitor C12, and the ninth node O9 is connected to the second end of the sixth coil W6.

Specifically, when the grid voltage is a negative half cycle during charging of the high-voltage battery pack 70, as shown in fig. 6, the third switching tube Q3 and the fourth switching tube Q4 are controlled to be turned on, or, as shown in fig. 7, the second switching tube Q2 is controlled to be turned off, the first switching tube Q1, the third switching tube Q3 and the fourth switching tube Q4 are controlled to be turned on, and the second resonant circuit module 20 is turned on; the grid voltage is applied to the eighth capacitor C8, and the control module 50 controls the fifth switching tube Q5 and the sixth switching tube Q6 to be turned on or off at a fixed frequency and a fixed duty ratio, and charges and discharges the ninth capacitor C9 and the tenth capacitor C10, so that an alternating voltage is formed between a sixth node O6, which is a midpoint of the fifth switching tube Q5 and the sixth switching tube Q6, and a seventh node O7, which is a midpoint of the ninth capacitor C9 and the tenth capacitor C10. After the isolation and the voltage transformation of the second transformer T2, the eleventh switch tube Q11, the twelfth switch tube Q12, the eleventh capacitor C11 and the twelfth capacitor C12 form a rectification circuit, the control module 50 controls the on/off of the eleventh switch tube Q11 and the twelfth switch tube Q12 to charge and discharge the eleventh capacitor C11 and the twelfth capacitor C12, and converts an alternating current voltage between a midpoint of the eleventh switch tube Q11 and the twelfth switch tube Q12, i.e., the eighth node O8, and a midpoint of the eleventh capacitor C11 and the twelfth capacitor C12, i.e., the ninth node O9, into a direct current voltage to be output, i.e., voltages at two ends of the sixth capacitor C6, so as to implement the alternating current-direct current conversion.

The voltage on the sixth capacitor C6 is proportional to the absolute value of the power grid voltage, and since the output voltage waveforms of the first resonant circuit module 10 and the second resonant circuit module 20 are the steamed bread waves, a large-capacity electrolytic capacitor is not needed for filtering, so that a small-capacity capacitor, such as a film capacitor, can be selected as the capacitor C6.

Further, the first dc conversion circuit module 40 regulates the input dc voltage to supply to the high voltage battery pack 70. Specifically, when the eighth switching tube Q8 is turned on, the current of the fourth inductor L4 increases, and the current flows in a → L4 → Q8 → B as shown in fig. 6 or 7; the eighth switching tube Q8 is turned off, and the current of the fourth inductor L4 decreases, as shown in fig. 6 or 7, and the current flows in a → L4 → Q7 → battery pack → B. The control module 50 performs high-frequency on-off control on the eighth switching tube Q8, so that the current waveform of the fourth inductor L4 tracks the voltage of the sixth capacitor C6, power factor correction can be achieved, and the current amplitude of the fourth inductor L4 depends on the charging power.

Further, as shown in fig. 6 or 7, the secondary side of the first transformer T1 further includes a third coil W3 and a fourth coil W4, a second end of the third coil W3 and a first end of the fourth coil W4 are a first common end, and the first common end is connected to a first end of the second dc conversion circuit module 41.

The first rectifier circuit module 80 includes a thirteenth switch tube Q13 and a fourteenth switch tube Q14, wherein a first end of the thirteenth switch tube Q13 is connected to the first end of the third coil W3, a second end of the thirteenth switch tube Q13 is connected to the second end of the second dc converting circuit module 41, a control end of the thirteenth switch tube Q13 is connected to the control module 50, a first end of the fourteenth switch tube Q14 is connected to the second end of the fourth coil W4, a second end of the fourteenth switch tube Q14 is connected to the second end of the second dc converting circuit module 41, and a control end of the fourteenth switch tube Q14 is connected to the control module 50.

The secondary side of the second transformer T2 further includes a seventh coil W7 and an eighth coil W8, wherein a second end of the seventh coil W7 and a first end of the eighth coil W8 are a second common end, and the second common end is connected to the first end of the second dc conversion circuit module 41.

The second rectifying circuit module 41 includes a fifteenth switching tube Q15 and a sixteenth switching tube Q16, a first end of the fifteenth switching tube Q15 is connected to the first end of the seventh coil W7, a second end of the fifteenth switching tube Q15 is connected to the second end of the second dc conversion circuit module 41, a control end of the fifteenth switching tube Q15 is connected to the control module 50, a first end of the sixteenth switching tube Q16 is connected to the second end of the eighth coil W8, a second end of the sixteenth switching tube Q16 is connected to the second end of the second dc conversion circuit module 41, and a control end of the sixteenth switching tube Q16 is connected to the control module 50.

Further, the second dc conversion circuit module 41 includes a thirteenth capacitor C13, a seventeenth switch Q17, an eighteenth switch Q18 and a fourteenth capacitor C14.

A first end of the thirteenth capacitor C13 is connected to the first common end, and a second end of the thirteenth capacitor C13 is respectively connected to a second end of the thirteenth switching tube Q13, a second end of the fourteenth switching tube Q14, a second end of the fifteenth switching tube Q15, and a second end of the sixteenth switching tube Q16.

The first end of the seventeenth switching tube Q17 is connected to the first end of the thirteenth capacitor C13 through the eighth inductor L8, the second end of the seventeenth switching tube Q17 is connected to the second end of the thirteenth capacitor C13 and the first end of the low-voltage battery pack 71, the control end of the seventeenth switching tube Q17 is connected to the control module 50, the first end of the eighteenth switching tube Q18 is connected to the eighth inductor L8 and the first end of the seventeenth switching tube Q17, the second end of the eighteenth switching tube Q18 is connected to the second end of the low-voltage battery pack 71, and the control end of the eighteenth switching tube Q18 is connected to the control module 50.

A first end of the fourteenth capacitor C14 is connected to the second end of the eighteenth switch tube Q18 and the second end of the low-voltage battery pack 71, respectively, and a second end of the fourteenth capacitor C14 is connected to the second end of the seventeenth switch tube Q17 and the first end of the low-voltage battery pack 71, respectively.

Specifically, when the power grid is used for charging the battery pack, during a first half period of power supply, for example, a positive half period of the power grid, the first resonant circuit module 10 is turned on, the first resonant circuit module 10 outputs a direct current to the first direct current conversion circuit 40 to charge the high-voltage battery pack 70, and at the same time, rectification is realized through on/off control of the thirteenth switching tube Q13 and the fourteenth switching tube Q14 of the first rectification circuit module 80, specifically, when the third coil W3 and the fourth coil W4 are positive and negative, the fourteenth switching tube Q14 is turned on, the thirteenth switching tube Q13 is turned off, and a direct current voltage is output; when the third coil W3 and the fourth coil W4 are in the up-down positive state, the fourteenth switching tube Q14 is not conducted, the thirteenth switching tube Q13 is conducted, and a direct current voltage is output, that is, a direct current voltage is provided at two ends of the thirteenth capacitor C13.

Further, the second dc converting circuit module 41 is a dc converting circuit such as a BOOST circuit, which can achieve power factor correction and output power regulation, wherein the eighteenth switch Q18 is kept on, specifically, when the seventeenth switch Q17 is on, the eighth inductor L8 is in the energy storage stage, and the current rises, as shown in fig. 6 or 7, and the current direction is C → L8 → Q17 → D; when the seventeenth switching tube Q17 is turned off, the eighth inductor L8 releases energy, and the current decreases in the direction of C → L8 → Q18 → low voltage battery → D.

By turning on and off the seventeenth switching tube Q17 at a high frequency, the current waveform of the eighth inductor L8 tracks the voltage of the thirteenth capacitor C13, so as to implement power factor correction, where the current amplitude of the eighth inductor L8 depends on the charging power of the low-voltage battery.

Similarly, during a second half period of power supply, for example, a negative half period of the power grid, the second resonant circuit module 20 is turned on, the second resonant circuit module 20 outputs a direct current to the first direct current conversion circuit 40 to charge the high-voltage battery pack 70, and meanwhile, rectification is achieved through on/off control of the fifteenth switching tube Q15 and the sixteenth switching tube Q16 of the second rectifier circuit module 81, specifically, when the seventh winding W7 and the eighth winding W8 are positive and negative, the sixteenth switching tube Q16 is turned on, the fifteenth switching tube Q15 is not turned on, and a direct current voltage is output; when the seventh coil W7 and the eighth coil W8 are up-down, the sixteenth switching tube Q16 is not turned on, the fifteenth switching tube Q15 is turned on, and a dc voltage is output, i.e., a dc voltage is applied across the thirteenth capacitor C13.

Based on the circuit structure of the vehicle-mounted charging system 10 shown in fig. 6 or 7, the vehicle-mounted charging system can also operate in the discharging mode of the high-voltage battery pack 70, that is, the discharging of the high-voltage battery pack 70 is realized to supply power to the electric equipment, and the specific process is as follows.

When the vehicle-mounted charging system 10 works in a discharging mode, the high-voltage battery pack 70 discharges electricity and outputs direct current, the first direct current conversion circuit module 40 performs direct current-direct current conversion to realize a voltage regulation function, and the control module 50 controls gating of the resonant circuit according to the power supply cycle signal so as to gate the first resonant circuit module 10 or the second resonant circuit module 20 and output power frequency alternating current to supply power for the electric equipment or feed back the power to the power grid.

Referring to fig. 6 or 7, specifically, the switching timing of the first dc conversion circuit module 40 is: when the seventh switching tube Q7 is turned on, the current of the fourth inductor L4 rises, and the high-voltage battery pack 70 transfers energy to the subsequent circuit; when the seventh switching tube Q7 is turned off, the current of the fourth inductor L4 decreases, and the current continues to flow through the eighth switching tube Q8, and energy is transferred to the subsequent stage. The control module 50 regulates the output voltage, i.e., the voltage across the sixth capacitor C6, by controlling the on and off of the seventh switching tube Q7, and the voltage amplitude depends on the switching duty ratio of the seventh switching tube Q7 and the voltage of the high-voltage battery pack 70.

For the first resonant circuit module 10 and the second resonant circuit module 20, the first resonant circuit module 10 is gated on outputting a positive half cycle of the alternating current. Specifically, the ninth switching tube Q9 and the tenth switching tube Q10 are turned on or off at a fixed frequency and a fixed duty ratio, and the fourth capacitor C4 and the fifth capacitor C5 are charged or discharged, so that an alternating voltage is formed between a midpoint of the ninth switching tube Q9 and the tenth switching tube Q10, i.e., the third node O3, and a midpoint of the fourth capacitor C4 and the fifth capacitor C5, i.e., the fourth node O4. After the first transformer T1 is isolated, the third switching tube Q3, the fourth switching tube Q4, the second capacitor C2 and the third capacitor C3 realize a rectification function, and alternating voltage between the middle points of the third switching tube Q3 and the fourth switching tube Q4, namely the first node O1 and the middle points of the second capacitor C2 and the third capacitor C3, namely the second node O2 is converted into positive half-cycle part of power frequency alternating current, namely the voltage at two ends of the first capacitor C1 through the switching-on or switching-off of the third switching tube Q3 and the fourth switching tube Q4 and the charging or discharging of the second capacitor C2 and the third capacitor C3, so that the positive half-cycle part of the power frequency alternating current is output.

Likewise, the second resonant circuit module 20 is gated on the negative half-cycle of the alternating current output by the system. The eleventh switch tube Q11 and the twelfth switch tube Q12 are switched on or off at a fixed frequency and a fixed duty cycle, and the eleventh capacitor C11 and the twelfth capacitor C12 are charged or discharged, so that an alternating voltage is formed between a midpoint of the eleventh switch tube Q11 and the twelfth switch tube Q12, i.e., the eighth node O8, and a midpoint of the eleventh capacitor C11 and the twelfth capacitor C12, i.e., the ninth node O9. After the transformation and isolation of the second transformer T2, the fifth switching tube Q5, the sixth switching tube Q6, the ninth capacitor C9 and the tenth capacitor C10 realize a rectification function, and through the conduction or the disconnection of the fifth switching tube Q5 and the sixth switching tube Q6 and the charging or the discharging of the ninth capacitor C9 and the eleventh capacitor C10, the alternating-current voltage between the midpoint of the fifth switching tube Q5 and the sixth switching tube Q6, i.e., the sixth node O6, and the midpoint of the ninth capacitor C9 and the tenth capacitor C10, i.e., the seventh node O7, is converted into the negative half-cycle of the power-frequency alternating current, i.e., the voltages at the two ends of the eighth capacitor C8, so as to realize the negative half-cycle output of the power-frequency alternating current.

The switching timing for the gating control of the resonant circuit module is: when the system outputs a positive half-cycle signal of the alternating current, as shown in fig. 6, the fifth switching tube Q5 and the sixth switching tube Q6 are controlled to be kept on, or, as shown in fig. 7, the fifth switching tube Q5, the sixth switching tube Q6 and the second switching tube Q2 are controlled to be kept on, and the first switching tube Q1 is controlled to be turned off, so as to gate the first resonant circuit module 10; when the system outputs a negative half-cycle signal of the alternating current, as shown in fig. 6, the third switching tube Q3 and the fourth switching tube Q4 are controlled to be turned on, or, as shown in fig. 7, the second switching tube Q2 is controlled to be turned off, the first switching tube Q1, the third switching tube Q3 and the fourth switching tube Q4 are controlled to be turned on, and the second resonant circuit module 20 is gated.

Based on the in-vehicle charging system shown in fig. 6 or 7, it is also possible to operate in a mode in which the high-voltage battery pack 70 charges the low-voltage battery pack 71. In this mode, the first dc conversion circuit module 40, the secondary part of the first resonance circuit module 10, the secondary part of the second resonance circuit module 20, the first and second

rectifier circuit modules

80 and 81, and the second dc conversion circuit module 41 participate.

Specifically, when the seventh switching tube Q7 is turned on, the fourth inductor L4 is in the energy storage stage, the current rises, and the high-voltage battery pack 70 transmits energy to the post-stage circuit; when the seventh switch Q7 is turned off, the current of the fourth inductor L4 decreases, and the fourth inductor L4 supplies energy to the subsequent stage. The first dc conversion circuit module 40, for example, the buck circuit, outputs a voltage across the sixth capacitor C6, and the voltage across the sixth capacitor C6 can be adjusted by adjusting the duty ratio of the eighth switching tube Q7.

Alternating current voltage is formed between a middle point of the ninth switching tube Q9 and the tenth switching tube Q10, namely a third node O3, and a middle point of the fourth capacitor C4 and the fifth capacitor C5, namely a fourth node O4 by controlling the ninth switching tube Q9 and the tenth switching tube Q10 to be switched on or switched off at a certain frequency and duty ratio and charging or discharging the fourth capacitor C4 and the fifth capacitor C5, and alternating current-alternating current conversion, isolation and transformation are realized through isolation and transformation of the first transformer T1. The secondary part of the first resonant circuit module 10 is in parallel connection with the secondary part of the second resonant circuit module 20, the time for starting the operation of the secondary part of the second resonant circuit module 20 is delayed from the time for starting the operation of the secondary part of the first resonant circuit module 10, and the operation processes are the same. By controlling the eleventh switch tube Q11 and the twelfth switch tube Q12 to be turned on or off at a certain frequency and duty ratio and the charge or discharge of the eleventh capacitor C11 and the twelfth capacitor C12, an alternating voltage is formed between a midpoint of the eleventh switch tube Q11 and the twelfth switch tube Q12, i.e., the eighth node O8, and a midpoint of the eleventh capacitor C11 and the twelfth capacitor C12, i.e., the ninth node O9, and the alternating current-alternating current transformation and isolation are realized through the isolation of the second transformer T2.

Further, the first rectifier circuit module 80 and the second rectifier circuit module 81 convert the ac voltages of the third coil W3 and the fourth coil W4 of the first transformer T1 and the seventh coil W7 and the eighth coil W8 of the second transformer T2 into dc voltages, and when the third coil W3 and the fourth coil W4 are positive and negative, the fourteenth switching tube Q14 is turned on, the thirteenth switching tube Q13 is turned off, and dc voltages are output; when the third coil W3 and the fourth coil W4 are up-down positive, the fourteenth switching tube Q14 is not conducted, the thirteenth switching tube Q13 is conducted, and the dc voltage is output. The second rectifier circuit module 81 starts operating at a time delayed from the time of the first rectifier circuit module 80, and the operation is the same. When the seventh coil W7 and the eighth coil W8 are positive and negative, the sixteenth switching tube Q16 is turned on, the fifteenth switching tube Q15 is turned off, and a direct-current voltage is output; when the seventh coil W7 and the eighth coil W8 are up-down positive, the sixteenth switching tube Q16 is not conducted, the fifteenth switching tube Q15 is conducted, and outputs direct-current voltage to the low-voltage battery pack 71, so that the high-voltage power supply 70 charges the low-voltage battery pack 71. In this operating mode, in the second dc conversion circuit module 41, the seventeenth switching tube Q17 is kept off, and the eighteenth switching tube Q18 is kept on.

In the embodiment of the present invention, when the high-voltage battery pack 70 discharges to the low-voltage battery pack 71, the two output current ripples are alternately superimposed to charge the low-voltage battery pack 71 through the relative delay of the operating time of the first rectifier circuit module 80 and the second rectifier circuit module 81, so that the current ripples are reduced, and the charging efficiency is improved.

In the embodiment of the present invention, the switching tube may be a MOS tube or a triode or other suitable switching device.

In addition, for the Part of Part2' in fig. 1 being an LLC topology, when the output voltage range is wide, the switching frequency deviates more from the resonant frequency, resulting in low charging efficiency. The vehicle-mounted charging system 100 according to the embodiment of the invention can adjust the duty ratio of the operation of the dc conversion circuit module at the rear stage through the control module 50 to control the charging power, and the adaptable battery voltage range is wider.

In summary, in the vehicle-mounted charging system 100 according to the embodiment of the present invention, the control module 50 controls the gated resonance circuit module and the rectification circuit module according to the power supply cycle signal through the two resonance circuit modules and the two rectification circuit modules, so that the signals output to the conversion circuit module by the resonance circuit module and the rectification circuit module are steamed bread waves, and therefore, a large-capacity electrolytic capacitor is not needed for filtering, only a small-capacity filter device, such as a thin-film capacitor, is needed, the cost and the volume of the electrolytic capacitor part are reduced, and the reliability and the service life of the product are improved. And, the charging of the low voltage battery pack 71 can be realized through the first rectifier circuit module 80 and the second rectifier circuit module 81, and current ripples can be reduced due to the delay of the rectification operating time, and the charging efficiency is improved, and the gating function can be realized without setting a separate gating circuit module, reducing the number of used circuit devices, or even if the gating circuit module is designed, gating is realized through series-parallel control of the switching tubes, conduction energy consumption can be reduced, and a larger battery voltage range can be adapted through the adjustment of the operating duty ratio of the dc conversion circuit module, and charging power is provided.

Based on the on-vehicle charging system of the above embodiment, a vehicle according to an embodiment of the second aspect of the invention is described below with reference to the drawings.

FIG. 8 is a block diagram of a vehicle according to one embodiment of the present invention. As shown in fig. 8, a vehicle 1000 according to an embodiment of the present invention includes a high-voltage battery pack 70, a low-voltage battery pack 71, and the vehicle-mounted charging system 100 according to the above embodiment, wherein the components of the vehicle-mounted charging system 100 can refer to the description of the above embodiment, and of course, the vehicle 1000 further includes other systems such as a transmission system, a power system, a steering system, and the like, which are not listed here.

According to the vehicle 1000 of the embodiment of the invention, by adopting the vehicle-mounted charging system 100 of the embodiment, the cost can be reduced, the reliability can be improved, the anti-seismic grade can be improved, and the charging of the low-voltage battery pack can be realized.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an illustrative embodiment," "an example," "a specific example," or "some examples" or the like mean 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 invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example.

While embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. An in-vehicle charging system, characterized by comprising:

the first resonant circuit module is used for converting an input electric signal and comprises a first conversion unit, a first transformer and a second conversion unit, wherein the first conversion unit comprises a third switching tube and a fourth switching tube, the first end of the third switching tube is connected with the first end of the electric unit, the second end of the third switching tube is connected with the first end of the fourth switching tube, the first conversion unit is connected with the primary side of the first transformer, and the secondary side of the first transformer is connected with the second conversion unit;

the second resonant circuit module is used for converting an input electric signal, and comprises a third conversion unit, a second transformer and a fourth conversion unit, wherein the third conversion unit comprises a fifth switching tube and a sixth switching tube, the first end of the fifth switching tube is connected with the second end of the electric unit, the second end of the fifth switching tube is connected with the first end of the sixth switching tube, and the second end of the sixth switching tube is connected with the second end of the fourth switching tube, wherein the third conversion unit is connected with the primary side of the second transformer, and the secondary side of the second transformer is connected with the fourth conversion unit;

the first end of the first rectifying circuit module is connected with the secondary side of the first transformer and used for rectifying an input electric signal;

a second rectifier circuit module, a first end of which is connected to a secondary side of the second transformer, for rectifying an input electrical signal;

a first end of the first dc conversion circuit module is connected to the second conversion unit and the fourth conversion unit, respectively, and a second end of the first dc conversion circuit module is connected to the high-voltage battery pack and is configured to perform dc-dc conversion on an input electrical signal;

the first end of the second direct current conversion circuit module is connected with the first rectification circuit module and the second rectification circuit module, and the second end of the second direct current conversion circuit module is connected with the low-voltage battery pack and used for performing direct current-direct current conversion on an input electric signal;

and the control module is used for controlling a fifth switching tube and a sixth switching tube to be kept conducted during a first half period of power supply, and respectively controlling the first resonant circuit module and the first rectifying circuit module according to a time sequence signal of the first half period of power supply, or controlling the third switching tube and the fourth switching tube to be kept conducted during a second half period of power supply, and respectively controlling the second resonant circuit module and the second rectifying circuit module according to a time sequence signal of the second half period of power supply, or respectively controlling the second conversion unit, the first rectifying circuit module, the fourth conversion unit and the second rectifying circuit module according to a control time sequence of charging a low-voltage battery pack by a high-voltage battery pack.

2. The vehicle-mounted charging system according to claim 1, further comprising:

the gating circuit module comprises a first switching tube and a second switching tube, wherein the first end of the first switching tube is connected with the first end of the electric unit, the second end of the first switching tube is respectively connected with the second end of the fourth switching tube and the second end of the sixth switching tube, the first end of the second switching tube is connected with the second end of the electric unit, and the second end of the second switching tube is respectively connected with the second end of the fourth switching tube and the second end of the sixth switching tube;

the control module is further configured to control the first switching tube to be turned off, control the second switching tube, the fifth switching tube and the sixth switching tube to be turned on, and control the first resonant circuit module and the first rectification circuit module according to a timing signal of a first half period of power supply when the first half period of power supply is performed; or, when the power supply is performed for the second half period, the second switching tube is controlled to be turned off, the first switching tube, the third switching tube and the fourth switching tube are controlled to be turned on, and the second resonant circuit module and the second rectifier circuit module are controlled according to the timing sequence signal of the second half period of the power supply, or the second conversion unit, the first rectifier circuit module, the fourth conversion unit and the second rectifier circuit module are controlled according to the control timing sequence of the high-voltage battery pack for charging the low-voltage battery pack.

3. The in-vehicle charging system according to claim 2,

the first conversion unit further comprises a first capacitor, a second capacitor and a third capacitor, wherein a first end of the first capacitor is connected with a first end of the electric unit, a second end of the first capacitor is connected with a second end of the fourth switching tube, a first end of the third switching tube is connected with the first end of the first capacitor, a control end of the third switching tube is connected with the control module, a second end of the third switching tube is connected with the first end of the fourth switching tube, a control end of the fourth switching tube is connected with the control module, a first node is arranged between the second end of the third switching tube and the first end of the fourth switching tube, a first end of the second capacitor is connected with the first end of the third switching tube, a second end of the second capacitor is connected with the first end of the third capacitor, a second end of the third capacitor is connected with the second end of the fourth switching tube, and a second node is arranged between the second end of the second capacitor and the first end of the third capacitor;

the first transformer comprises a first coil and a second coil, a first end of the first coil is connected with the first node through a first inductor, a second end of the first coil is connected with the second node, and a second inductor is connected between the first end of the first coil and the second end of the second coil;

the second conversion unit comprises a ninth switching tube, a tenth switching tube, a fourth capacitor and a fifth capacitor, wherein the first end of the ninth switching tube is connected with the first end of the first dc conversion circuit module, the control end of the ninth switching tube is connected with the control module, the second end of the ninth switching tube is connected with the first end of the tenth switching tube, the second end of the tenth switching tube is connected with the second end of the first dc conversion circuit module, the control end of the tenth switching tube is connected with the control module, a third node is arranged between the second end of the ninth switching tube and the first end of the tenth switching tube, the third node is connected with the first end of the second coil through a third inductor, the first end of the fourth capacitor is connected with the first end of the ninth switching tube and the first end of the second dc conversion circuit module, the second end of the fourth capacitor is connected with the first end of the fifth capacitor, the second end of the fifth capacitor is connected with the second end of the tenth switching tube, the second end of the fourth capacitor is connected with the second end of the tenth switching tube, the second capacitor is connected with the second end of the fourth capacitor, and the second capacitor is connected with the second node of the fourth capacitor, and the second end of the fourth capacitor is connected with the fourth capacitor.

4. The vehicle-mounted charging system according to claim 3, wherein the first DC conversion circuit module comprises:

a first end of the sixth capacitor is connected with a first end of the ninth switching tube, and a second end of the sixth capacitor is connected with a second end of the tenth switching tube;

a seventh switching tube and an eighth switching tube, wherein a first end of the seventh switching tube is connected with a first end of the high-voltage battery pack, a control end of the seventh switching tube is connected with the control module, a second end of the seventh switching tube is connected with a first end of the eighth switching tube, a second end of the eighth switching tube is respectively connected with a second end of the sixth capacitor and a second end of the high-voltage battery pack, a control end of the eighth switching tube is connected with the control module, a fifth node is arranged between the second end of the seventh switching tube and the first end of the eighth switching tube, and the fifth node is connected with the first end of the sixth capacitor through a fourth inductor;

and a first end of the seventh capacitor is connected with the first end of the seventh switch tube and the first end of the high-voltage battery pack respectively, and a second end of the seventh capacitor is connected with the second end of the eighth switch tube and the second end of the high-voltage battery pack respectively.

5. The vehicle-mounted charging system according to claim 4,

the third conversion unit further comprises an eighth capacitor, a ninth capacitor and a tenth capacitor, wherein a first end of the eighth capacitor is connected to the second end of the electrical unit and the first end of the fifth switching tube, a control end of the fifth switching tube is connected to the control module, a second end of the eighth capacitor is connected to the second end of the sixth switching tube, a control end of the sixth switching tube is connected to the control module, a sixth node is arranged between the second end of the fifth switching tube and the first end of the sixth switching tube, the first end of the ninth capacitor is connected to the first end of the fifth switching tube, the second end of the ninth capacitor is connected to the first end of the tenth capacitor, the second end of the tenth capacitor is connected to the second end of the sixth switching tube, and a seventh node is arranged between the second end of the ninth capacitor and the first end of the tenth capacitor;

the second transformer comprises a fifth coil and a sixth coil, a first end of the fifth coil is connected with the sixth node through a fifth inductor, a second end of the fifth coil is connected with the seventh node, and a sixth inductor is connected between the first end of the fifth coil and the second end of the fifth coil;

the fourth conversion unit comprises an eleventh switching tube, a twelfth switching tube, an eleventh capacitor and a twelfth capacitor, wherein a first end of the eleventh switching tube is connected with a first end of the sixth capacitor, a control end of the eleventh switching tube is connected with the control module, a second end of the eleventh switching tube is connected with a first end of the twelfth switching tube, a second end of the twelfth switching tube is connected with a second end of the sixth capacitor, a control end of the twelfth switching tube is connected with the control module, an eighth node is arranged between the second end of the eleventh switching tube and the first end of the twelfth switching tube, the eighth node is connected with the first end of the sixth coil through a seventh inductor, the first end of the eleventh capacitor is connected with the first end of the eleventh switching tube, the second end of the eleventh capacitor is connected with the first end of the twelfth capacitor, the second end of the twelfth capacitor is connected with the second end of the twelfth switching tube, and the ninth node is arranged between the second end of the eleventh capacitor and the ninth coil.

6. The vehicle-mounted charging system according to claim 5,

the secondary side of the first transformer further comprises a third coil and a fourth coil, a second end of the third coil and a first end of the fourth coil are a first common end, and the first common end is connected with a first end of the second direct current conversion circuit module;

the first rectifying circuit module comprises a thirteenth switching tube and a fourteenth switching tube, wherein the first end of the thirteenth switching tube is connected with the first end of the third coil, the second end of the thirteenth switching tube is connected with the second end of the second direct current conversion circuit module, the control end of the thirteenth switching tube is connected with the control module, the first end of the fourteenth switching tube is connected with the second end of the fourth coil, the second end of the fourteenth switching tube is connected with the second end of the second direct current conversion circuit module, and the control end of the fourteenth switching tube is connected with the control module.

7. The vehicle-mounted charging system according to claim 6,

the secondary side of the second transformer further comprises a seventh coil and an eighth coil, wherein a second end of the seventh coil and a first end of the eighth coil are a second common end, and the second common end is connected with a first end of the second direct current conversion circuit module;

the second rectifying circuit module comprises a fifteenth switching tube and a sixteenth switching tube, wherein the first end of the fifteenth switching tube is connected with the first end of the seventh coil, the second end of the fifteenth switching tube is connected with the second end of the second direct current conversion circuit module, the control end of the fifteenth switching tube is connected with the control module, the first end of the sixteenth switching tube is connected with the second end of the eighth coil, the second end of the sixteenth switching tube is connected with the second end of the second direct current conversion circuit module, and the control end of the sixteenth switching tube is connected with the control module.

8. The vehicle-mounted charging system according to claim 7, wherein the second direct-current conversion circuit module includes:

a thirteenth capacitor, a first end of the thirteenth capacitor is connected to the first common terminal, and a second end of the thirteenth capacitor is connected to the second end of the thirteenth switching tube, the second end of the fourteenth switching tube, the second end of the fifteenth switching tube, and the second end of the sixteenth switching tube, respectively;

a seventeenth switching tube and an eighteenth switching tube, wherein a first end of the seventeenth switching tube is connected with a first end of the thirteenth capacitor through an eighth inductor, a second end of the seventeenth switching tube is respectively connected with a second end of the thirteenth capacitor and a first end of the low-voltage battery pack, a control end of the seventeenth switching tube is connected with the control module, a first end of the eighteenth switching tube is respectively connected with the eighth inductor and the first end of the seventeenth switching tube, a second end of the eighteenth switching tube is connected with a second end of the low-voltage battery pack, and a control end of the eighteenth switching tube is connected with the control module;

and a fourteenth capacitor, a first end of which is connected to the second end of the eighteenth switch tube and the second end of the low-voltage battery pack, and a second end of which is connected to the second end of the seventeenth switch tube and the first end of the low-voltage battery pack.

9. A vehicle characterized by comprising a high-voltage battery pack, a low-voltage battery pack, and the on-vehicle charging system according to any one of claims 1 to 8.