CN117507871A

CN117507871A - Vehicle, charging system, and control method thereof

Info

Publication number: CN117507871A
Application number: CN202210907351.5A
Authority: CN
Inventors: 凌和平; 闫磊; 常东博; 袁帅; 李申
Original assignee: BYD Co Ltd
Current assignee: BYD Co Ltd
Priority date: 2022-07-29
Filing date: 2022-07-29
Publication date: 2024-02-06

Abstract

The present disclosure proposes a vehicle, a charging system, and a control method thereof, the charging system including: the method comprises the following steps of: acquiring charging demand information of a battery pack, and acquiring output capability information of charging equipment connected with M charging ports; and controlling the step-up and step-down circuit according to the charging demand information and the output capacity information. According to the control method of the charging system, through the arrangement of the buck-boost circuit, the buck-boost circuit can be controlled to charge multiple guns according to the output capacity of the charging equipment connected with the M charging ports, so that the charging equipment with different highest output voltage platforms can be compatible, quick charging can be realized, the charging efficiency can be improved, and the charging time can be shortened.

Description

Vehicle, charging system, and control method thereof

Technical Field

The present disclosure relates to the field of charging technologies, and in particular, to a vehicle, a charging system, and a control method thereof

Background

With the rapid development of new energy automobiles, the battery pack of the electric automobile is higher and higher in electric quantity, and the driving range is longer and longer, and accordingly, the charging speed of the electric automobile is also a problem of increasing attention. However, the charging system in the related art has a technical problem of low charging rate.

Disclosure of Invention

The present disclosure aims to solve, at least to some extent, one of the technical problems in the related art. Therefore, a first object of the present disclosure is to provide a control method of a charging system, so as to be compatible with charging devices of different highest output voltage platforms, so as to rapidly charge, thereby improving charging efficiency and shortening charging time.

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

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

To achieve the above object, an embodiment of a first aspect of the present disclosure provides a control method of a charging system, the charging system including M charging ports, a buck-boost circuit and a battery pack, the M charging ports are all connected to the battery pack through the buck-boost circuit, and M is an integer greater than 1, the method includes the following steps: acquiring charging demand information of the battery pack, and acquiring output capability information of charging equipment connected with the M charging ports; and controlling the step-up and step-down circuit according to the charging demand information and the output capacity information.

According to the control method of the charging system, through the arrangement of the step-up and step-down circuits in the charging system and according to the output capacity of the charging equipment connected with the M charging ports, the step-up and step-down circuits are controlled to charge in multiple guns, so that the charging equipment with different highest output voltage platforms can be compatible, the charging efficiency can be improved, and the charging time can be shortened.

To achieve the above object, an embodiment of a second aspect of the present disclosure provides a charging system, M charging ports, a buck-boost circuit, a controller and a battery pack, where the M charging ports are all connected to the battery pack through the buck-boost circuit, and the controller is connected to a control end of the buck-boost circuit, and configured to obtain charging demand information of the battery pack, and obtain output capability information of a charging device connected to the M charging ports, and control the buck-boost circuit according to the charging demand information and the output capability information, where M is an integer greater than 1.

According to the charging system disclosed by the embodiment of the disclosure, through the arrangement of the buck-boost circuit, the output capacity of the charging equipment connected with the M charging ports can be realized, the buck-boost circuit is controlled to charge in a plurality of guns, so that the charging equipment with different highest output voltage platforms can be compatible, the charging efficiency can be improved, and the charging time can be shortened.

To achieve the above object, an embodiment of a third aspect of the present disclosure proposes a vehicle including the charging system according to the embodiment of the first aspect.

According to the vehicle disclosed by the embodiment of the disclosure, through the charging system, charging equipment with different highest output voltage platforms can be compatible, so that the vehicle can be charged quickly, the charging efficiency can be improved, and the charging time can be shortened.

Additional aspects and advantages of the disclosure 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 disclosure.

Drawings

Fig. 1 is a schematic structural view of a charging system according to an embodiment of the present disclosure;

FIG. 2 is a flow chart of a method of controlling a charging system of an embodiment of the present disclosure;

FIG. 3 is a flow chart of step S22 of one embodiment of the present disclosure;

FIG. 4 is a flow chart of a control method of an exemplary charging system of the present disclosure;

FIG. 5 is a flow chart of a method of controlling a charging system of another example of the present disclosure;

fig. 6 is a schematic structural view of a charging system according to another embodiment of the present disclosure;

fig. 7 is a schematic structural view of a charging system according to a first embodiment of the present disclosure;

fig. 8 is a schematic structural view of a charging system according to a second embodiment of the present disclosure;

fig. 9 is a schematic structural view of a charging system according to a third embodiment of the present disclosure;

fig. 10 is a schematic structural view of a charging system according to a fourth embodiment of the present disclosure;

fig. 11 is a schematic structural view of a charging system according to a fifth embodiment of the present disclosure;

fig. 12 is a schematic structural view of a charging system according to a sixth embodiment of the present disclosure;

FIG. 13 is a schematic diagram of an operational phase one of a charging system of one embodiment of the present disclosure;

FIG. 14 is a schematic diagram of an operational phase two of a charging system according to one embodiment of the present disclosure;

FIG. 15 is a schematic diagram of an operational phase one of a charging system according to another embodiment of the present disclosure;

fig. 16 is a schematic diagram of an operational phase two of a charging system according to another embodiment of the present disclosure;

FIG. 17 is a flowchart of the operation of a charging system of one embodiment of the present disclosure;

fig. 18 is a block diagram of a vehicle according to an embodiment of the present disclosure.

Detailed Description

Embodiments of the present disclosure 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 exemplary and intended for the purpose of explaining the present disclosure and are not to be construed as limiting the present disclosure.

A vehicle, a charging system, and a control method thereof according to an embodiment of the present disclosure are described below with reference to the accompanying drawings.

Fig. 1 is a schematic structural view of a charging system according to an embodiment of the present disclosure.

As shown in fig. 1, a charging system of an embodiment of the present disclosure includes: m charging ports (fig. 1 illustrates m=2, and the 2 charging ports are respectively denoted as a first charging port 1 and a second charging port 2), a step-up/step-down circuit 3, and a battery pack 5, and the M charging ports are all connected to the battery pack 5 through the step-up/step-down circuit 3, where M is an integer greater than 1.

Based on the charging system, the disclosure provides a control method of the charging system. Fig. 2 is a flowchart of a control method of the charging system of the embodiment of the present disclosure.

As shown in fig. 2, the control method of the charging system includes:

s21, acquiring charging demand information of the battery pack, and acquiring output capability information of charging equipment connected with the M charging ports.

S22, controlling the step-up/step-down circuit according to the charging demand information and the output capability information.

Specifically, the M charging ports are used for connecting M charging guns, and the M charging guns can respectively belong to N different charging devices, wherein N is less than or equal to M. When the battery pack 5 is charged through the M charging ports, the M charging ports are connected to the N charging devices through the M charging guns. At this time, the charging demand information (e.g., charging demand voltage) of the battery pack 5 may be acquired, the output capability information (e.g., outputting the highest voltage, outputting the highest current, etc.) of the N charging devices may be acquired, the charging control mode (e.g., single-gun full-open mode, single-gun boost mode, double-gun full-open mode, double-gun boost mode, etc.) may be determined according to the charging demand information and the output capability information, and the buck-boost circuit 3 may be controlled (e.g., full-open control, buck-boost control, etc.) according to the charging control mode.

Therefore, the control method of the charging system of the embodiment of the disclosure can be compatible with charging equipment with different highest output voltage platforms, and the battery pack 5 can be rapidly charged by adopting a corresponding charging mode no matter whether the charging voltage range of the charging equipment connected with the charging port is lower than or higher than the highest allowable charging voltage of the battery pack 5, so that the charging efficiency can be improved, and the charging time can be shortened.

In some embodiments, the charging system further includes M switch circuits, where the M switch circuits are in one-to-one correspondence with the M charging ports, and the switch circuits are connected between the step-up and step-down circuits and the corresponding charging ports, the charging demand information includes a demand charging voltage, and the output capability information includes a highest output voltage, or a highest output voltage and a highest output current.

In this embodiment, as shown in fig. 3, controlling the step-up/step-down circuit according to the charging demand information and the output capability information in step S22 includes:

and S31, when the highest output voltage of the charging equipment corresponding to the M charging ports is larger than or equal to the required charging voltage, controlling the M switch circuits to be closed, and performing full-open control on the buck-boost circuit.

Specifically, if the highest output voltage of the charging device corresponding to each charging port is greater than or equal to the required charging voltage, it is indicated that the charging device corresponding to each charging port can directly charge the battery pack, at this time, the M switch circuits can be controlled to be closed, and the buck-boost circuit is fully controlled, and at the same time, each charging device can output the required voltage to charge the battery pack. Thus, the charging speed can be increased by charging a plurality of guns simultaneously.

S32, when the highest output voltage of the charging equipment corresponding to the M charging ports is smaller than the required charging voltage, controlling the M switch circuits to be closed, and performing boost control on the boost-buck circuit.

Specifically, if the highest output voltage of the charging device corresponding to each charging port is smaller than the required charging voltage, it is indicated that the charging device corresponding to each charging port cannot directly charge the battery pack independently, at this time, the M switch circuits can be controlled to be closed, the step-up/step-down circuit is controlled to be boosted, and meanwhile, the output voltage of each charging device can reach the required voltage after being boosted to charge the battery pack. Therefore, the battery pack can be charged by the charging equipment with small output capacity, and the simultaneous charging of multiple guns can be realized, so that the charging speed can be improved.

And S33, when the highest output voltage of the charging equipment corresponding to at least one charging port is larger than or equal to the required charging voltage and the highest output voltage of the charging equipment corresponding to at least one charging port is smaller than the required charging voltage, controlling the M switch circuits and the buck-boost circuits according to the required charging voltage, the highest output voltage and the highest output current of each charging equipment.

Specifically, if the highest output voltage of the charging device corresponding to at least one charging port is greater than or equal to the required charging voltage and the highest output voltage of the charging device corresponding to at least one charging port is less than the required charging voltage, it is indicated that some charging devices corresponding to the charging ports can realize direct charging of the battery pack, and some charging devices cannot, at this time, when charging of multiple guns is required, the charging capacity of each charging device is judged, so as to determine a control strategy for the buck-boost circuit and on-off control for the switching circuit, and achieve a better charging effect.

In a specific embodiment, the M charging ports include a first charging port and a second charging port, and the charging device connected to the first charging port is denoted as a first charging device, and the charging device connected to the second charging port is denoted as a second charging device.

In this specific embodiment, as an example, as shown in fig. 4, when the highest output voltage of the first charging device is greater than or equal to the required charging voltage and the highest output voltage of the second charging device is less than the required charging voltage, the M switching circuits and the step-up/down circuits are controlled according to the required charging voltage, the highest output voltage and the highest output current of each charging device, including:

S41, calculating to obtain first charging power according to the required charging voltage and the highest output current of the first charging equipment, and calculating to obtain second charging power according to the highest output current of the first charging equipment, the highest output voltage and the highest output current of the second charging equipment.

And S42, when the first charging power is larger than the second charging power, controlling the switch circuit corresponding to the first charging port to be closed, controlling the switch circuit corresponding to the second charging port to be opened, and controlling the buck-boost circuit to be fully opened.

And S43, when the first charging power is smaller than or equal to the second charging power, controlling the switch circuits corresponding to the first charging port and the second charging port to be closed, and performing boost control on the buck-boost circuit.

As another example, as shown in fig. 5, when the highest output voltage of the first charging device is smaller than the required charging voltage and the highest output voltage of the second charging device is greater than or equal to the required charging voltage, controlling M switching circuits and step-up/down circuits according to the required charging voltage, the highest output voltage and the highest output current of each charging device, includes:

and S51, calculating to obtain third charging power according to the highest output voltage and highest output current of the first charging equipment and the highest output current of the second charging equipment, and calculating to obtain fourth charging power according to the required charging voltage and the highest output current of the second charging equipment.

And S52, when the third charging power is smaller than or equal to the fourth charging power, the switching circuit corresponding to the first charging port is controlled to be opened, the switching circuit corresponding to the second charging port is controlled to be closed, and the full-open control is carried out on the buck-boost circuit.

And S53, when the third charging power is larger than the fourth charging power, the switch circuits corresponding to the first charging port and the second charging port are controlled to be closed, and the step-up and step-down circuit is controlled to be boosted.

Specifically, note that U0 is a required charging voltage of the battery pack, U1 is a highest output voltage of the first charging device, U2 is a highest output voltage of the second charging device, I1 is a highest output current of the first charging device, and I2 is a highest output current of the second charging device.

If U1 is equal to or greater than U0 and U2 is less than U0, calculating a first charging power p1=u0×i1 and a second charging power p2=u2× (i1+i2). If P1 > P2, it indicates that the independent charging efficiency of the first charging device is higher, at this time, it can be determined that the charging control mode is full-open control of the first charging device, the second charging device is not charged, and then the switching circuit corresponding to the first charging port is controlled to be closed, the switching circuit corresponding to the second charging port is controlled to be opened, and full-open control is performed on the buck-boost circuit. If P1 is less than or equal to P2, the dual-gun charging efficiency is higher, and the charging control mode can be determined to be the simultaneous boost control of the first charging equipment and the second charging equipment, so that the switch circuits corresponding to the first charging port and the second charging port are controlled to be closed, and the boost control is performed on the boost circuit.

If U1 < U0, U2 is equal to or greater than U0, calculating third charging power p3= U1 (i1+i2), and fourth charging power p4= U0I 2. If P3 is less than or equal to P4, the second charging device is higher in single charging efficiency, at the moment, the charging control mode can be determined to be full-open control of the second charging device, the first charging device is not charged, and then the switching circuit corresponding to the first charging port is controlled to be opened, the switching circuit corresponding to the second charging port is controlled to be closed, and full-open control is performed on the buck-boost circuit. If P3 > P4, it indicates that the dual-gun charging efficiency is higher, at this time, it can be determined that the charging control mode is the simultaneous boost control of the first charging device and the second charging device, so as to control the switch circuits corresponding to the first charging port and the second charging port to be closed, and perform the boost control on the boost circuit.

Optionally, the charging device may obtain a charging demand voltage of the power battery when the charging device and the vehicle charge handshake; when the charging demand voltage > the maximum output voltage Umax of the charging device, the step-down operation is performed by controlling the step-up and step-down circuit so that the voltage of the charging port is below the maximum output voltage of the charging device.

In summary, according to the control method of the charging system in the embodiment of the disclosure, through the arrangement of the buck-boost circuit, different charging control modes can be selected according to the output capacities of a plurality of charging devices, so that the charging devices with different output voltage platforms can be compatible for quick charging at the same time, and meanwhile, the charging mode with the highest charging efficiency can be selected for charging, thereby being beneficial to improving the charging efficiency and shortening the charging time.

Fig. 6 is a schematic structural view of a charging system according to another embodiment of the present disclosure.

As shown in fig. 6, the charging system of the embodiment of the present invention includes: m charging ports (fig. 1 illustrates m=2, and the 2 charging ports are respectively denoted as a first charging port 1 and a second charging port 2), a step-up/step-down circuit 3, a controller 4, and a battery pack 5, where M is an integer greater than 1. The first end of each charging port is connected with charging equipment, and the second end of each charging port is connected with the first end of the step-up/step-down circuit 3; the battery pack 5 is connected with the second end of the buck-boost circuit 3; the controller 4 is connected to a control terminal of the step-up/step-down circuit 3, and the controller 4 is configured to: the charging demand information of the battery pack 5 and the output capability information of the charging device corresponding to each charging port are acquired, and the step-up/down circuit 3 is controlled to perform multi-gun charging according to the charging demand information and the output capability information.

Therefore, the charging system can be compatible with charging equipment with different highest output voltage platforms, and the battery pack 5 can be rapidly charged by adopting a corresponding charging mode no matter whether the charging voltage range of the charging equipment connected with the charging port is lower than or higher than the highest allowable charging voltage of the battery pack 5, so that the charging efficiency can be improved, and the charging time can be shortened.

Fig. 7 is a schematic structural view of a charging system according to a first embodiment of the present disclosure. As shown in fig. 7, the step-up/step-down circuit 3 includes: the three-phase capacitor comprises an N-phase bridge arm, N first inductors L1 and a first capacitor C1, wherein N is a positive integer (N=1 is taken as an example in fig. 7), and the N-phase bridge arm corresponds to the N first inductors L1 one by one.

Referring to fig. 7, each phase of bridge arm is connected in parallel with a first capacitor C1, N phase of bridge arms are connected in parallel, a first bus end of the N phase of bridge arms after being connected in parallel is connected with a positive electrode of the battery pack 5, and a second bus end of the N phase of bridge arms after being connected in parallel is connected with a negative electrode of the battery pack 5, wherein N is a positive integer. N first inductors L1 are in one-to-one correspondence with N-phase bridge arms, the first end of each first inductor L1 is connected with the middle point of the corresponding bridge arm, the second end of each first inductor L1 is connected with the positive electrode of each charging port, and the negative electrode of each charging port is connected with the second bus end.

As one example, each phase leg includes a first switch assembly and a second switch assembly, the first switch assembly being in series with the second switch assembly. Referring to fig. 7, the first switching assembly includes a first switching tube VT1 and a first diode VD1, the second switching assembly includes a second switching tube VT2 and a second diode VD2, the first diode VD1 is connected in parallel with the first switching tube VT1, and the second diode VD2 is connected in parallel with the second switching tube VT 2. The midpoint of each phase bridge arm is the connection point between the corresponding first switching tube VT1 and the second switching tube VT 2.

In some embodiments of the present disclosure, referring to fig. 7, the charging system may further include M switching circuits (fig. 2 illustrates m=2, and the 2 switching circuits are respectively denoted as a first switching circuit 61 and a second switching circuit 62), where the M switching circuits are in one-to-one correspondence with the M charging ports, and the switching circuits are connected between the buck-boost circuit 3 and the corresponding charging ports. In this embodiment, the controller 4 is further connected to control terminals of the M switch circuits for controlling the M switch circuits according to the charging control mode.

Specifically, referring to fig. 7, taking the value of M as 2 as an example, the first switch circuit 61 corresponding to the first charging port 1 includes a contactor K4 and a contactor K7, and the second switch circuit 61 corresponding to the second charging port 2 includes a contactor K5 and a contactor K8. When the battery pack 5 needs to be charged through the first charging port 1, the controller 4 needs to control the K4 and the K7 to be closed; when the battery pack 5 needs to be charged through the second charging port 1, the controller 4 needs to control the K5 and K6 to be closed. Meanwhile, the controller 4 can also control the on-off of the VT1 and VT2 according to the requirement so as to realize the boost-buck charging of the battery pack 5.

As an example, referring to fig. 7, the charging system may further include: and the second capacitor C2 is connected between the second end of the first inductor L1 and the second bus end and is used for filtering and stabilizing the charging voltage input by each charging port.

As an example, referring to fig. 7, the charging system may further include a main positive contactor K2 and a precharge circuit 7. The main positive contactor K2 is connected between the positive electrode of the battery pack 5 and the first bus terminal; the precharge circuit 7 includes a precharge contactor K3 and a precharge resistor R connected in series, and is connected in parallel with the main positive contactor K2. Optionally, referring to fig. 2, the charging system may further include a main negative contactor K1 connected between the negative electrode of the battery pack 5 and the negative electrode of the step-up/step-down circuit 3.

Fig. 8 is a schematic diagram of a charging system according to a second embodiment of the present disclosure, and fig. 9 is a schematic diagram of a buck-boost circuit 3 according to a third embodiment of the present disclosure.

As shown in fig. 8 and 9, the charging system further includes: and a second inductance L2. Referring to fig. 8, the second inductor L2 is connected between the first inductor L1 and the positive electrode of the first charging port 1. Referring to fig. 9, the second inductor L2 is connected between the first inductor L1 and the positive electrode of the second charging port 2.

Thus, by providing the second inductance L2, it is possible to suppress a circulation current that may occur when the highest output current is simultaneously outputted between the two charging devices connected to the two charging ports.

In some embodiments of the present disclosure, the charging system is for a vehicle, the N-phase bridge arm multiplexes the N-phase control bridge arms in the motor controller of the vehicle, and the N first inductances L1 multiplex the N motor coil inductances of the vehicle.

Fig. 10 is a schematic structural view of a charging system according to a fourth embodiment of the present disclosure.

As shown in fig. 10, when N is equal to 3, the 3 bridge arms are respectively denoted as a first bridge arm, a second bridge arm and a third bridge arm, where the first bridge arm is composed of a switch tube VT1, a switch tube VT2, a diode VD1 and a diode VD2, the second bridge arm is composed of a switch tube VT3, a switch tube VT4, a diode VD3 and a diode VD4, and the third bridge arm is composed of a switch tube VT5, a switch tube VT6, a diode VD5 and a diode VD 6. Meanwhile, referring to fig. 5, 3 inductors respectively connected with the 3 bridge arms may further multiplex 3 motor coil inductors L3. Therefore, the charging system can reduce the use of devices by multiplexing the motor electric control assembly, thereby reducing the cost and the occupied space of the charging system.

Alternatively, referring to fig. 10, a change-over switch (such as a contactor K6 in fig. 10) may be connected between the motor coil inductance L3 and the M switching circuits, and at the same time, a second capacitor C2 is connected between an end of the contactor K6 remote from L3 and the negative electrode of the buck-boost circuit 3. Through the setting of contactor K6, can realize multiplexing motor automatically controlled subassembly to charging system, and do not influence motor automatically controlled subassembly's normal drive control. That is, when the vehicle is running normally, K6 is disconnected, and L3 and 3 bridge arms are used for driving control; when the vehicle stops charging, K6 is closed for realizing charging of the charging system.

Fig. 11 is a schematic structural view of a charging system according to a fifth embodiment of the present disclosure, and fig. 12 is a schematic structural view of a charging system according to a sixth embodiment of the present disclosure.

The difference between fig. 11 and fig. 8, and the difference between fig. 12 and fig. 9 is that the configuration of the step-up/down circuit 3 is different, and the configuration of the step-up/down circuit 3 shown in fig. 5 is adopted as the configuration of the different step-up/down circuit 3. In the same manner as in fig. 8, 9, 11 and 12, by providing the second inductance L2, it is possible to suppress a circulation current which may occur when the highest output current is simultaneously outputted between the two charging devices connected to the two charging ports.

In some embodiments of the present disclosure, the charging demand information includes a demand charging voltage, the output capability information includes a highest output voltage and a highest output current, and the controller 4 is further configured to:

when the highest output voltage of the charging equipment corresponding to each charging port is larger than or equal to the required charging voltage, controlling the M switching circuits to be closed, and performing full-open control on the buck-boost circuit 3;

when the highest output voltage of the charging corresponding to each charging port is smaller than the required charging voltage, controlling the M switch circuits to be closed and performing boost control on the boost circuit 3;

Otherwise (i.e. the highest output voltage of the charging device corresponding to the at least one charging port is greater than or equal to the required charging voltage, and the highest output voltage of the charging device corresponding to the at least one charging port is less than the required charging voltage), the opening or closing of the M switch circuits is controlled according to the required charging voltage, and the buck-boost circuit 3 is controlled according to the highest output voltage and the highest output current.

In a specific embodiment, the charging device connected to the first charging port 1 is a first charging device, the charging device connected to the second charging port 2 is a second charging device, the output capability information of the first charging device includes a first highest output voltage U1 and a first highest output current I1, and the capability information of the second charging device includes a second highest output voltage U2 and a second highest output current I2, and the required charging voltage is U0.

In this embodiment, as an example, the controller 4 is further configured to:

when the first highest output voltage of the first charging device is greater than or equal to the required charging voltage, and the second highest output voltage of the second charging device is less than the required charging voltage, that is, U1 is greater than or equal to U0, and U2 is less than U0, calculating according to the required charging voltage and the first highest output current of the first charging device to obtain a first charging power P1, such as p1=u0×i1, and calculating according to the first highest output current of the first charging device, the second highest output voltage of the second charging device, and the second highest output current to obtain a second charging power P2, such as p2=u2 (i1+i2); when the first charging power is larger than the second charging power, namely P1 is larger than P2, the switching circuit corresponding to the first charging port 1 is controlled to be closed, the switching circuit corresponding to the second charging port 2 is controlled to be opened, and the full-open control is carried out on the step-up/step-down circuit 3; when the first charging power is smaller than or equal to the second charging power, that is, P1 is smaller than or equal to P2, the switch circuits corresponding to the first charging port 1 and the second charging port 2 are controlled to be closed, and the step-up and step-down circuit 3 is controlled to be boosted.

As another example, the controller 4 is also configured to:

when the first highest output voltage of the first charging device is smaller than the required charging voltage, the second highest output voltage of the second charging device is larger than or equal to the required charging voltage, namely U1 is smaller than U0, U2 is larger than or equal to U0, calculating to obtain third charging power P3 according to the first highest output voltage of the first charging device, the first highest output current and the second highest output current of the second charging device, wherein the third charging power P3 is calculated according to the required charging voltage and the highest output current of the second charging device, and calculating to obtain fourth charging power P4 according to the required charging voltage and the highest output current of the second charging device, wherein the fourth charging power P4 is calculated according to the first highest output voltage, the first highest output current and the second highest output current of the second charging device, and the fourth charging power P4 is calculated according to the first highest output current of the first charging device and the second highest output current of the second charging device; when the third charging power is smaller than or equal to the fourth charging power, namely P3 is smaller than or equal to P4, the switching circuit corresponding to the first charging port 1 is controlled to be opened, the switching circuit corresponding to the second charging port 2 is controlled to be closed, and the full-open control is carried out on the step-up/step-down circuit 3; when the third charging power is greater than the fourth charging power, that is, P3 is greater than P4, the switch circuits corresponding to the first charging port 1 and the second charging port 2 are controlled to be closed, and the boost control is performed on the boost-buck circuit 3.

Specifically, the first charging device fully-open control charging power and dual-gun simultaneous boost control charging power judging process comprises the following steps:

The first charging power p1=u0×i1, the second charging power p2=u2×i1+i2, if P1 > P2, determining that the charging control mode is full-on control of the first charging device and the second charging device is not charged; if P1 is less than or equal to P2, determining that the charging control mode is simultaneous boost control of the first charging equipment and the second charging equipment.

The full-open control charging power of the second charging equipment and the simultaneous boost control charging power judging process of the double guns are as follows:

the third charging power p3= =u1 (i1+i2), the fourth charging power p4=u0×i2, if p3+.p4, determining that the charging control mode is the full-on control of the second charging device and the first charging device is not charged; if P3 > P4, determining that the charging control mode is simultaneous boost control of the first charging device and the second charging device.

The following describes the operation principle of the charging system according to the embodiment of the present disclosure, taking the case where the charging voltage range of one of the two charging devices is lower than the highest allowable charging voltage of the battery pack 5, and the dual gun simultaneous boost charging as illustrated in fig. 13 to 16:

Fig. 13 is a schematic diagram of an operation phase one of a charging system according to an embodiment of the present disclosure, and fig. 14 is a schematic diagram of an operation phase two of a charging system according to an embodiment of the present disclosure.

As shown in fig. 13, in the first stage of the charging process, the switching tube VT2 is controlled to be turned on, the inductor L1 is charged by the first charging loop and the second charging loop simultaneously, and the current flow direction of the first charging loop is: the current flow direction of the second charging loop is as follows: the anode of the second charging port 2, the contactor K8, the inductor L1, the switching tube VT2, the contactor K5 and the cathode of the second charging port 2.

As shown in fig. 14, in the second stage of the charging process, the switching tube VT2 is controlled to be turned off, the voltage of the inductor L1 is simultaneously superimposed by the first charging loop and the second charging loop to charge the battery pack 5, and the current flow direction of the first charging loop is as follows: the first charging port 1 positive electrode, the contactor K7, the inductance L1, the diode VD1, the contactor K2, the battery pack 5, the contactor K1, the contactor K4, the first charging port 1 negative electrode, and the second charging loop current flow direction is as follows: the anode of the second charging port 2, the contactor K8, the inductor L1, the diode VD1, the contactor K2, the battery pack 5, the contactor K1, the contactor K5 and the cathode of the second charging port 2.

Therefore, the boost conversion can be realized through the alternate control of the stage one and the stage two, so that the simultaneous boost charging of the double guns is realized.

When the charge control mode is the full-on control, the switching transistor VT2 is not controlled to be turned on or off to perform the boost conversion, and the current directly flows through the diode VD1 to charge the battery pack 5, and the current flow of the simultaneous charging of the two guns is identical to that shown in fig. 14.

Fig. 15 is a schematic diagram of a first operating stage of a charging system according to another embodiment of the present disclosure, and fig. 16 is a schematic diagram of a second operating stage of the charging system according to another embodiment of the present disclosure.

As shown in fig. 15, in the first stage of the charging process, the switching transistors VT2, VT4, VT6 are controlled to be turned on, the first charging loop and the second charging loop charge the motor coil inductance L3 at the same time, and the current flow direction of the first charging loop is: the current flow direction of the second charging loop is as follows: the anode of the second charging port 2, the contactor K8, the contactor K6, the inductor L3, the switching tubes VT2, VT4 and VT6, the contactor K5 and the cathode of the second charging port 2.

As shown in fig. 16, in the second stage of the charging process, the switching transistors VT2, VT4, VT6 are controlled to be turned off, the first charging loop and the second charging loop simultaneously superimpose the voltage of the motor coil inductance L3 to charge the battery pack 5, and the current flow direction of the first charging loop is: the current flow direction of the second charging loop is as follows: the anode of the second charging port 2, the contactor K8, the contactor K6, the motor coil inductance L3, the diodes VD1, VD3 and VD5, the contactor K2, the battery pack 5, the contactor K1, the contactor K5 and the cathode of the second charging port 2.

When the charging control mode is full-on control, the switching tubes VT2, VT4, VT6 are not controlled to be turned on or off to perform boost conversion, and the current directly flows through the diodes VD1, VD3, VD5 to charge the battery pack 5, so that the current flow of the simultaneous charging of the two guns is identical to that shown in fig. 16.

The workflow of the charging system of the embodiment of the present disclosure is described below with reference to fig. 17:

Fig. 17 is a flowchart of the operation of a charging system of one embodiment of the present disclosure.

In this embodiment, the charging gun connected to the first charging port 1 is a first charging gun, the charging gun connected to the second charging port is a second charging gun, and the first charging gun and the second charging gun are respectively assigned to the first charging device and the second charging device. Referring to fig. 17, the workflow of the charging system includes:

s1, detecting whether a first charging port is connected with a first charging gun, if so, executing S2, otherwise, continuing to detect;

s2, carrying out charging handshake confirmation with the first charging equipment, and acquiring the highest output voltage of the first charging equipment;

s3, judging whether the highest output voltage of the first charging equipment is higher than the highest allowable charging voltage of the battery pack, if so, executing S4, otherwise, executing S5;

s4, fully-opened control of the first charging equipment is carried out, and S6 is carried out;

s5, the first charging equipment boosting control is carried out, and the process goes to S13;

s6, detecting whether the second charging port is connected with a second charging gun, if so, executing S7, otherwise, continuing to detect;

s7, carrying out charging handshake confirmation with the second charging equipment, and acquiring the highest output voltage of the second charging equipment;

s8, judging whether the highest output voltage of the second charging equipment is higher than the highest allowable charging voltage of the battery pack, if so, executing S9, otherwise, executing S10;

S9, the first charging equipment and the second charging equipment are simultaneously controlled to be fully opened;

s10, judging whether the full-open control charging power of the first charging equipment is larger than the double-gun boosting control charging power, if so, executing S11, otherwise, executing S12;

s11, full-open control is performed on the first charging equipment, and the second charging equipment is not charged;

s12, the first charging equipment and the second charging equipment are subjected to boost control at the same time;

s13, detecting whether the second charging port is connected with a second charging gun, if so, executing S14, otherwise, continuing to detect;

s14, carrying out charging handshake confirmation with the second charging equipment, and acquiring the highest output voltage of the second charging equipment;

s15, judging whether the highest output voltage of the second charging equipment is higher than the highest allowable charging voltage of the battery pack, if so, executing S16, otherwise, executing S12;

s16, judging whether the full-open control charging power of the second charging equipment is larger than the double-gun boosting control charging power, if so, executing S17, otherwise, executing S12;

s17, the first charging equipment is not charged, and the second charging equipment is fully-opened.

In summary, according to the charging system of the embodiment of the disclosure, through the setting of the step-up and step-down circuit, different charging control modes can be selected according to the output capacities of a plurality of charging devices, so that the charging devices with different output voltage platforms can be compatible for multi-gun simultaneous quick charging, and meanwhile, the charging mode with the highest charging efficiency can be selected for charging, thereby being beneficial to improving the charging efficiency and shortening the charging time.

As shown in fig. 18, a vehicle 100 includes the charging system 10 of the above example.

According to the vehicle disclosed by the embodiment of the disclosure, through the charging system of the embodiment, charging equipment compatible with different output voltage platforms can be charged rapidly at the same time in multiple guns, and meanwhile, the mode with the highest charging efficiency can be selected for charging, so that the charging efficiency is improved, and the charging time is shortened.

It should be noted that the logic and/or steps represented in the flowcharts or otherwise described herein, for example, may be considered as a ordered listing of executable instructions for implementing logical functions, and may be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). In addition, the computer readable medium may even be paper or other suitable medium on which the program is printed, as the program may be electronically captured, via, for instance, optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner, if necessary, and then stored in a computer memory.

It should be understood that portions of the present disclosure 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 disclosure. 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.

In the description of the present disclosure, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present disclosure and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present disclosure.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present disclosure, the meaning of "a plurality" is at least two, such as two, three, etc., unless explicitly specified otherwise.

In the present disclosure, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the terms in this disclosure will be understood by those of ordinary skill in the art as the case may be.

In this disclosure, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact through an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

Although embodiments of the present disclosure have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the present disclosure, 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 present disclosure.

Claims

1. A control method of a charging system, wherein the charging system includes M charging ports, a buck-boost circuit, and a battery pack, the M charging ports are all connected to the battery pack through the buck-boost circuit, and M is an integer greater than 1, the method comprising the steps of:

acquiring charging demand information of the battery pack, and acquiring output capability information of charging equipment connected with the M charging ports;

and controlling the step-up and step-down circuit according to the charging demand information and the output capacity information.

2. The control method of a charging system according to claim 1, wherein the charging system further includes M switch circuits, the M switch circuits being in one-to-one correspondence with the M charging ports, the switch circuits being connected between the step-up and step-down circuits and the corresponding charging ports, the charging demand information including a required charging voltage, the output capability information including a highest output voltage, or the highest output voltage and highest output current, the step-up and step-down circuits being controlled according to the charging demand information and the output capability information, comprising:

When the highest output voltage of the charging equipment corresponding to the M charging ports is larger than or equal to the required charging voltage, controlling the M switch circuits to be closed, and performing full-open control on the buck-boost circuit;

when the highest output voltage of the charging equipment corresponding to the M charging ports is smaller than the required charging voltage, controlling the M switch circuits to be closed, and performing boost control on the boost circuit;

when the highest output voltage of the charging equipment corresponding to at least one charging port is larger than or equal to the required charging voltage and the highest output voltage of the charging equipment corresponding to at least one charging port is smaller than the required charging voltage, the M switching circuits and the step-up/step-down circuits are controlled according to the required charging voltage, the highest output voltage and the highest output current of each charging equipment.

3. The method for controlling a charging system according to claim 2, wherein the M charging ports include a first charging port and a second charging port, the charging device connected to the first charging port is a first charging device, the charging device connected to the second charging port is a second charging device, and when a highest output voltage of the first charging device is greater than or equal to the required charging voltage, a highest output voltage of the second charging device is less than the required charging voltage,

Calculating to obtain first charging power according to the required charging voltage and the highest output current of the first charging equipment, and calculating to obtain second charging power according to the highest output current of the first charging equipment, the highest output voltage and the highest output current of the second charging equipment;

when the first charging power is larger than the second charging power, the switching circuit corresponding to the first charging port is controlled to be closed, the switching circuit corresponding to the second charging port is controlled to be opened, and the full-open control is carried out on the step-up/step-down circuit;

when the first charging power is smaller than or equal to the second charging power, the switch circuits corresponding to the first charging port and the second charging port are controlled to be closed, and the step-up and step-down circuit is controlled to be boosted.

4. The charging system of claim 3, wherein when the highest output voltage of the first charging device is less than the required charging voltage, the highest output voltage of the second charging device is greater than or equal to the required charging voltage,

calculating to obtain third charging power according to the highest output voltage and highest output current of the first charging equipment and the highest output current of the second charging equipment, and calculating to obtain fourth charging power according to the required charging voltage and the highest output current of the second charging equipment;

When the third charging power is smaller than or equal to the fourth charging power, the switching circuit corresponding to the first charging port is controlled to be opened, the switching circuit corresponding to the second charging port is controlled to be closed, and the full-open control is carried out on the step-up and step-down circuit;

when the third charging power is larger than the fourth charging power, the switch circuits corresponding to the first charging port and the second charging port are controlled to be closed, and the boost control is performed on the boost-buck circuit.

5. A charging system, the charging system comprising:

the charging device comprises M charging ports, a buck-boost circuit, a controller and a battery pack, wherein the M charging ports are connected to the battery pack through the buck-boost circuit, the controller is connected with a control end of the buck-boost circuit and used for acquiring charging demand information of the battery pack and acquiring output capacity information of charging equipment connected with the M charging ports, and the buck-boost circuit is controlled according to the charging demand information and the output capacity information, wherein M is an integer larger than 1.

6. The charging system of claim 5, wherein the buck-boost circuit comprises:

A first capacitor;

the N-phase bridge arms are connected in parallel with the first capacitor, the N-phase bridge arms are connected in parallel, a first bus end of the N-phase bridge arms after being connected in parallel is connected with the positive electrode of the battery pack, and a second bus end of the N-phase bridge arms after being connected in parallel is connected with the negative electrode of the battery pack, wherein N is a positive integer;

the N first inductors are in one-to-one correspondence with the N-phase bridge arms, the first end of each first inductor is connected with the middle point of the corresponding bridge arm, the second end of each first inductor is connected with the positive electrode of each charging port, and the negative electrode of each charging port is connected with the second converging end.

7. The charging system of claim 6, wherein each phase leg comprises a first switch assembly and a second switch assembly, said first switch assembly being connected in series with said second switch assembly;

the first switch assembly comprises a first switch tube and a first diode, and the first diode is connected with the first switch tube in parallel;

the second switch assembly comprises a second switch tube and a second diode, and the second diode is connected with the second switch tube in parallel;

the controller is connected with the control ends of the first switching tube and the second switching tube and is used for controlling the on-off of the first switching tube and the second switching tube.

8. The charging system of claim 6, further comprising M switching circuits in one-to-one correspondence with the M charging ports, the switching circuits being connected between the buck-boost circuit and the corresponding charging ports;

the second capacitor is connected between the second end of the first inductor and the second bus end; the controller is further connected with control ends of the M switch circuits and used for controlling the M switch circuits.

9. The charging system of claim 6, wherein the charging system further comprises:

the main positive contactor is connected between the positive electrode of the battery pack and the first bus end;

and the precharge circuit comprises a precharge contactor and a precharge resistor which are connected in series, and the precharge circuit is connected with the main positive contactor in parallel.

10. The charging system of claim 6, wherein said N-phase leg multiplexes N control legs in a motor controller of said vehicle, and said N first inductances multiplex N motor coil inductances of said vehicle.

11. The charging system of claim 2, wherein the M charging ports include a first charging port and a second charging port, the charging system further comprising:

The second inductor is connected between the first inductor and the positive electrode of the first charging port, or between the first inductor and the positive electrode of the second charging port.

12. A vehicle comprising a charging system according to claims 5-11.