阅读说明：本技术 一种充放电方法、系统、控制器及电动汽车 (Charging and discharging method, system, controller and electric automobile ) 是由 彭龙飞 范涛 孙志飞 冉彦杰 郑援 唐德钱 于 2019-09-30 设计创作，主要内容包括：本发明涉及一种充放电方法、系统、控制器及电动汽车,以实现电动汽车的交流充放电和直流充放电的效果。该系统包括：动力电池包；与动力电池包连接的双向DC/DC转换器；与双向DC/DC转换器连接的双向车载充电机OBC；交流充放电接口,其通过第一开关连接双向车载充电机OBC；用于与直流充放电枪连接的直流充放电接口,其通过第二开关连接双向DC/DC转换器；车内插座接口,其通过第三开关连接双向车载充电机OBC；控制器,控制器分别连接双向DC/DC转换器、双向车载充电机OBC、第一开关、第二开关和第三开关；控制器根据所获取到的工作参数,确定电动汽车的充放电模式,并按照所确定的充放电模式对双向DC/DC转换器、双向车载充电机OBC、第一开关、第二开关和第三开关进行控制。(The invention relates to a charging and discharging method, a charging and discharging system, a controller and an electric automobile, and aims to achieve the effects of alternating current charging and discharging and direct current charging and discharging of the electric automobile. The system comprises: a power battery pack; the bidirectional DC/DC converter is connected with the power battery pack; the bidirectional vehicle-mounted charger OBC is connected with the bidirectional DC/DC converter; the alternating current charging and discharging interface is connected with the bidirectional vehicle-mounted charger OBC through the first switch; the direct-current charging and discharging interface is used for being connected with the direct-current charging and discharging gun and is connected with the bidirectional DC/DC converter through a second switch; the in-vehicle socket interface is connected with the bidirectional vehicle-mounted charger OBC through a third switch; the controller is respectively connected with the bidirectional DC/DC converter, the bidirectional vehicle-mounted charger OBC, the first switch, the second switch and the third switch; the controller determines a charging and discharging mode of the electric automobile according to the acquired working parameters, and controls the bidirectional DC/DC converter, the bidirectional vehicle-mounted charger OBC, the first switch, the second switch and the third switch according to the determined charging and discharging mode.)

1. A charging and discharging system, comprising:

a power battery pack (1);

a bidirectional DC/DC converter (2) connected to the power battery pack (1);

a bidirectional on-board charger OBC (3) connected to the bidirectional DC/DC converter (2);

the alternating current charging and discharging interface (12) is connected with the alternating current charging and discharging gun and is connected with the bidirectional vehicle-mounted charger OBC (3) through a first switch (S1);

a DC charging/discharging interface (14) for connecting to a DC charging/discharging gun, the DC charging/discharging interface being connected to the bidirectional DC/DC converter (2) via a second switch (S2);

the in-vehicle socket interface (13) is used for being connected with in-vehicle electric equipment and is connected with the bidirectional vehicle-mounted charger OBC (3) through a third switch (S3);

a controller connected to the bidirectional DC/DC converter (2), the bidirectional on-board charger OBC (3), the first switch (S1), the second switch (S2) and the third switch (S3), respectively;

the controller determines a charging and discharging mode of the electric automobile according to the acquired working parameters, and controls the bidirectional DC/DC converter (2), the bidirectional vehicle-mounted charger OBC (3), the first switch (S1), the second switch (S2) and the third switch (S3) according to the determined charging and discharging mode.

2. The charging and discharging system according to claim 1, further comprising:

a fourth switch (K1) disposed between the in-vehicle receptacle interface (13) and the controller.

3. The charging and discharging system according to claim 2, further comprising:

the communication interface (8) is used for being connected with an electric device outside the vehicle, and the communication interface (8) is connected with the controller.

4. The charging and discharging system according to claim 3, further comprising:

and the low-voltage storage battery (4) is respectively connected with the controller, the bidirectional DC/DC converter (2) and the bidirectional vehicle-mounted charger OBC (3).

5. The charging and discharging system according to claim 4, wherein the controller comprises:

a control unit (5), said control unit (5) being connected to said low-voltage battery (4), said first switch (S1), said second switch (S2), said third switch (S3), said bidirectional DC/DC converter (2) and said bidirectional on-board charger OBC (3), respectively;

a detection unit (6) connected to the control unit (5) and the low-voltage battery (4), wherein the detection unit (6) is connected to the alternating-current charge-discharge interface (12), the fourth switch (K1), and the direct-current charge-discharge interface (14), respectively;

a communication unit (7) connected between the detection unit (6) and the communication interface (8).

6. A charging and discharging method applied to the charging and discharging system according to claim 4 or 5, comprising:

acquiring working parameter information detected from each vehicle-mounted interface, wherein the vehicle-mounted interface comprises: an alternating current charge-discharge interface (13), a direct current charge-discharge interface (14), an in-vehicle socket interface (13) and a communication interface (8);

determining a charging and discharging mode of the electric automobile according to the working parameter information;

and sending control signals to the bidirectional DC/DC converter (2), the bidirectional vehicle-mounted charger OBC (3), the first switch (S1), the second switch (S2) and the third switch (S3) according to the charging and discharging modes so as to work according to instructions corresponding to the charging and discharging modes.

7. The method of claim 6, wherein the operational parameter information detected from each vehicle mounted interface is: from the resistance value and CP voltage value of CC2 detected at the AC charge-discharge interface (12), or the resistance value of CC1 detected at the DC charging and discharging interface (14), or, an opening/closing signal of a fourth switch (K1) connected to the in-vehicle receptacle interface (13), or a charging signal of the electric equipment outside the vehicle detected from the communication interface (8) and a resistance value of CC2 detected from the alternating current charging and discharging interface (14), or the charging signal of the electric equipment outside the vehicle detected from the communication interface (8) and the resistance value of the CC1 detected from the direct current charging and discharging interface (14), or an opening/closing signal of a fourth switch (K1) connected to the in-vehicle socket interface (13), a charging signal of the electric equipment for vehicle exterior detected from the communication interface (8), and a resistance value of CC2 detected from the AC charging/discharging interface (12).

8. The method of claim 7, wherein the step of determining the charge-discharge mode of the electric vehicle according to the operating parameter information comprises:

if the resistance value of the CC2 detected from the alternating current charging and discharging interface (12) is R1 and the CP voltage value is U1, determining that the electric automobile is in an alternating current charging mode, wherein the alternating current charging mode is a mode for charging the power battery pack (1) through the alternating current charging and discharging interface (12);

if the resistance value of the CC1 detected from the direct current charging and discharging interface (14) is R3, determining that the electric automobile is in a direct current charging mode, wherein the direct current charging mode is a mode of charging the power battery pack (1) through the direct current charging and discharging interface (14);

if the on-off signal of a fourth switch (K1) connected with the in-vehicle socket interface (13) shows that the fourth switch (K1) is pressed for the first time, determining that the electric automobile is in an in-vehicle alternating current discharging mode, wherein the in-vehicle alternating current discharging mode is a mode that the power battery pack (1) supplies alternating current to in-vehicle alternating current electric equipment through the in-vehicle socket interface (13);

if the charging signal of the vehicle external electric equipment detected from the communication interface (8) is an alternating current charging demand signal of the vehicle external alternating current electric equipment and the resistance value of CC2 detected from the alternating current charging and discharging interface (12) is R2, determining that the electric vehicle is in a vehicle external alternating current discharging mode, wherein the vehicle external alternating current discharging mode is a mode of providing alternating current for the vehicle external alternating current electric equipment through the alternating current discharging interface;

if the charging signal of the vehicle external electric equipment detected from the communication interface (9) is a direct current charging demand signal of the vehicle external direct current electric equipment and the resistance value of CC1 detected from the alternating current charging and discharging interface (12) is R4, determining that the electric vehicle is in a vehicle external direct current discharging mode, wherein the vehicle external direct current discharging mode is a mode of providing direct current for the vehicle external direct current electric equipment through the direct current charging and discharging interface (14);

and if the opening and closing signal of a fourth switch (K1) connected with the in-vehicle socket interface (13) shows that the fourth switch (K1) is pressed for the first time, the charging signal of the electric equipment for outside the vehicle detected from the communication interface (8) is an alternating current charging demand signal of the alternating current electric equipment for outside the vehicle, and the resistance value of CC2 detected from the alternating current charging and discharging interface (12) is R2, determining that the electric vehicle is in an in-vehicle and in-vehicle synchronous alternating current discharging mode, wherein the in-vehicle and in-vehicle synchronous alternating current discharging mode is a mode of supplying alternating current to the electric equipment for outside the vehicle through the alternating current discharging interface (12) and supplying alternating current to the electric equipment for inside the vehicle through the in-vehicle socket interface (13).

9. The method according to claim 8, characterized in that the step of sending control signals to the bidirectional DC/DC converter (2), the bidirectional on-board charger OBC (3), the first switch (S1), the second switch (S2) and the third switch (S3) according to the charging and discharging mode to operate according to the command corresponding to the charging and discharging mode comprises:

if the electric automobile is in an alternating current charging mode, controlling the first switch (S1) to be closed, the second switch (S2) and the third switch (S3) to be opened, controlling the bidirectional vehicle-mounted charger OBC (3) to rectify alternating current input through the alternating current charging and discharging interface (12), and controlling the bidirectional DC/DC converter (2) to boost or buck rectified direct current to charge the power battery pack (1);

if the electric automobile is in a direct current charging mode, controlling the second switch (S2) to be closed, and the first switch (S1) and the third switch (S3) to be opened, and controlling the bidirectional DC/DC converter (2) to carry out voltage boosting or voltage reducing processing on direct current input by the direct current charging and discharging interface (14) so as to charge the power battery pack (1);

if the electric automobile is in an in-vehicle alternating current discharging mode, controlling the third switch (S3) to be closed, and the first switch (S1) and the second switch (S2) to be opened, controlling the bidirectional DC/DC converter (2) to carry out boosting or voltage reduction processing on the direct current output by the power battery pack (1), and then controlling the bidirectional vehicle-mounted charger OBC (3) to carry out inversion processing on the direct current output by the bidirectional DC/DC converter (2) so as to supply power to in-vehicle alternating current electric equipment through the in-vehicle socket interface (13);

if the electric automobile is in an external alternating current discharging mode, controlling the first switch (S1) to be closed, the second switch (S2) and the third switch (S3) to be disconnected, controlling the bidirectional DC/DC converter (2) to carry out boosting or voltage reduction on the direct current output by the power battery pack (1), and then controlling the bidirectional vehicle-mounted charger OBC (3) to carry out inversion on the direct current output by the bidirectional DC/DC converter (2) so as to supply power to external alternating current electric equipment through the alternating current charging and discharging interface (12);

if the electric automobile is in an automobile external direct current discharge mode, controlling the second switch (S2) to be closed, and the first switch (S1) and the third switch (S3) to be opened, and controlling the bidirectional DC/DC converter (2) to carry out voltage boosting or voltage reducing treatment on the direct current output by the power battery pack (1) so as to supply power to the automobile external direct current electric equipment through the direct current charge-discharge interface (14);

if the electric automobile is in an automobile internal and external synchronous alternating current discharging mode, the first switch (S1) and the third switch (S3) are controlled to be closed, the second switch (S2) is controlled to be opened, the bidirectional DC/DC converter (2) is controlled to perform boosting or voltage reduction processing on the direct current output by the power battery pack (1), and then the bidirectional vehicle-mounted charger OBC (3) is controlled to perform inversion processing on the direct current output by the bidirectional DC/DC converter (2), so that the alternating current electric equipment outside the automobile is supplied with power through the alternating current charging and discharging interface (12) and the alternating current electric equipment inside the automobile is supplied with power through the in-automobile socket interface (13).

10. A controller comprising a memory, a processor and a computer program stored on the memory and operable on the processor, wherein the processor reads the program in the memory and executes the steps of the charging and discharging method according to any one of claims 6 to 9.

11. An electric vehicle characterized by comprising the controller of claim 10.

Technical Field

The invention relates to the field of automobile charging and discharging, in particular to a charging and discharging method, a charging and discharging system, a controller and an electric automobile.

Background

With the continuous development of new energy electric vehicles, the charger of the new energy electric vehicle not only has a charging function, but also has a function of converting the electric energy of the battery of the electric vehicle into 220Vac alternating current for output.

The current charging or discharging control mode is single, and only the control of alternating current charging and discharging can be realized. The function and system control of direct current external discharge cannot be met.

Disclosure of Invention

The invention aims to provide a charging and discharging method, a charging and discharging system, a controller and an electric automobile so as to achieve the effects of alternating current charging and discharging and direct current charging and discharging of the electric automobile.

The technical scheme of the invention is as follows:

the present invention provides a charge and discharge system, comprising:

a power battery pack;

a bidirectional DC/DC converter connected with the power battery pack;

the bidirectional vehicle-mounted charger OBC is connected with the bidirectional DC/DC converter;

the alternating current charging and discharging interface is used for being connected with the alternating current charging and discharging gun and is connected with the bidirectional vehicle-mounted charger OBC through a first switch;

the direct-current charging and discharging interface is used for being connected with a direct-current charging and discharging gun and is connected with the bidirectional DC/DC converter through a second switch;

the in-vehicle socket interface is used for being connected with in-vehicle electric equipment and is connected with the bidirectional vehicle-mounted charger OBC through a third switch;

the controller is respectively connected with the bidirectional DC/DC converter, the bidirectional vehicle-mounted charger OBC, the first switch, the second switch and the third switch;

the controller determines a charging and discharging mode of the electric automobile according to the acquired working parameters, and controls the bidirectional DC/DC converter, the bidirectional vehicle-mounted charger OBC, the first switch, the second switch and the third switch according to the determined charging and discharging mode.

Preferably, the method further comprises the following steps:

a fourth switch disposed between the in-vehicle receptacle interface and the controller.

Preferably, the method further comprises the following steps:

the communication interface is used for being connected with the electric equipment outside the vehicle and is connected with the controller.

Preferably, the method further comprises the following steps:

and the low-voltage storage battery is respectively connected with the controller, the bidirectional DC/DC converter and the bidirectional vehicle-mounted charger OBC.

Preferably, the controller includes:

the control unit is respectively connected with the low-voltage storage battery, the first switch, the second switch, the third switch, the bidirectional DC/DC converter and the bidirectional vehicle-mounted charger OBC;

the detection unit is connected with the control unit and the low-voltage storage battery and is respectively connected with the alternating-current charging and discharging interface, the fourth switch and the direct-current charging and discharging interface;

a communication unit connected between the detection unit and the communication interface.

According to another aspect of the present invention, the present invention further provides a charging and discharging method applied to the charging and discharging system, including:

acquiring working parameter information detected from each vehicle-mounted interface, wherein the vehicle-mounted interface comprises: the system comprises an alternating current charge-discharge interface, a direct current charge-discharge interface, an in-vehicle socket interface and a communication interface;

determining a charging and discharging mode of the electric automobile according to the working parameter information;

and sending control signals to the bidirectional DC/DC converter, the bidirectional vehicle-mounted charger OBC, the first switch, the second switch and the third switch according to the charging and discharging mode so as to work according to an instruction corresponding to the charging and discharging mode.

Preferably, the operating parameter information detected from each vehicle-mounted interface is: the vehicle-mounted electrical equipment comprises a communication interface, a CC2 resistance value and a CP voltage value detected from the AC charging and discharging interface, or a CC1 resistance value detected from the DC charging and discharging interface, or an on-off signal of a fourth switch connected with the in-vehicle socket interface, or a charging signal of the external electrical equipment detected from the communication interface and a CC2 resistance value detected from the AC charging and discharging interface, or a charging signal of the external electrical equipment detected from the communication interface and a CC1 resistance value detected from the DC charging and discharging interface, or an on-off signal of a fourth switch connected with the in-vehicle socket interface, a charging signal of the external electrical equipment detected from the communication interface and a CC2 resistance value detected from the AC charging and discharging interface.

Preferably, the step of determining the charge and discharge mode of the electric vehicle according to the operating parameter information includes:

if the resistance value of the CC2 detected from the alternating current charging and discharging interface is R1 and the CP voltage value is U1, determining that the electric automobile is in an alternating current charging mode, wherein the alternating current charging mode is a mode for charging the power battery pack through the alternating current charging and discharging interface;

if the resistance value of CC1 detected from the direct current charge-discharge interface is R3, determining that the electric automobile is in a direct current charging mode, wherein the direct current charging mode is a mode of charging a power battery pack through the direct current charge-discharge interface;

if the on-off signal of a fourth switch connected with the in-vehicle socket interface shows that the fourth switch is pressed for the first time, determining that the electric automobile is in an in-vehicle alternating current discharging mode, wherein the in-vehicle alternating current discharging mode is a mode that a power battery pack supplies alternating current to in-vehicle alternating current electric equipment through the in-vehicle socket interface;

if the charging signal of the vehicle external electric equipment detected from the communication interface is an alternating current charging demand signal of the vehicle external alternating current electric equipment and the resistance value of CC2 detected from the alternating current charging and discharging interface is R2, determining that the electric vehicle is in a vehicle external alternating current discharging mode, wherein the vehicle external alternating current discharging mode is a mode of providing alternating current for the vehicle external alternating current electric equipment through the alternating current discharging interface;

if the charging signal of the vehicle external electric equipment detected from the communication interface is a direct current charging demand signal of the vehicle external direct current electric equipment and the resistance value of CC1 detected from the direct current charging and discharging interface is R4, determining that the electric vehicle is in a vehicle external direct current discharging mode, wherein the vehicle external direct current discharging mode is a mode of providing direct current for the vehicle external direct current electric equipment through the direct current charging and discharging interface;

and if the on-off signal of the fourth switch connected with the in-vehicle socket interface shows that the fourth switch is pressed for the first time, the charging signal of the electric equipment outside the vehicle detected from the communication interface is the alternating current charging demand signal of the alternating current electric equipment outside the vehicle, and the resistance value of CC2 detected from the alternating current charging and discharging interface is R2, determining that the electric vehicle is in an in-vehicle and in-vehicle synchronous alternating current discharging mode, wherein the in-vehicle and in-vehicle synchronous alternating current discharging mode is a mode of supplying alternating current to the alternating current electric equipment outside the vehicle through the alternating current discharging interface and supplying alternating current to the alternating current electric equipment inside the vehicle through the in-vehicle socket interface.

Preferably, the step of sending control signals to the bidirectional DC/DC converter, the bidirectional on-board charger OBC, the first switch, the second switch, and the third switch according to the charging and discharging mode to operate according to the instruction corresponding to the charging and discharging mode includes:

if the electric automobile is in an alternating current charging mode, controlling the first switch to be closed, the second switch and the third switch to be disconnected, controlling the bidirectional vehicle-mounted charger OBC to rectify alternating current input through the alternating current charging and discharging interface, and performing boosting or voltage reduction on the rectified direct current by the bidirectional DC/DC converter to charge the power battery pack;

if the electric automobile is in a direct current charging mode, controlling the second switch to be closed and the first switch and the third switch to be disconnected, and controlling the bidirectional DC/DC converter to carry out voltage boosting or voltage reduction on direct current input by the direct current charging and discharging interface so as to charge the power battery pack;

if the electric automobile is in an in-automobile alternating current discharging mode, controlling the third switch to be closed, and the first switch and the second switch to be disconnected, controlling the bidirectional DC/DC converter to carry out boosting or voltage reduction processing on the direct current output by the power battery pack, and then controlling the bidirectional vehicle-mounted charger OBC to carry out inversion processing on the direct current output by the bidirectional DC/DC converter so as to supply power to in-automobile alternating current electric equipment through the in-automobile socket interface;

if the electric automobile is in an external alternating current discharging mode, controlling the first switch to be closed, the second switch and the third switch to be disconnected, controlling the bidirectional DC/DC converter to perform voltage boosting or voltage reducing processing on the direct current output by the power battery pack, and then controlling the bidirectional vehicle-mounted charger OBC to perform inversion processing on the direct current output by the bidirectional DC/DC converter so as to supply power to external alternating current electric equipment through the alternating current charging and discharging interface;

if the electric automobile is in an automobile external direct current discharging mode, controlling the second switch to be closed, and the first switch and the third switch to be disconnected, and controlling the bidirectional DC/DC converter to carry out voltage boosting or voltage reducing processing on direct current output by the power battery pack so as to supply power to an automobile external direct current electric device through the direct current charging and discharging interface;

if the electric automobile is in an automobile internal and external synchronous alternating current discharging mode, the first switch and the third switch are controlled to be closed, the second switch is controlled to be disconnected, the bidirectional DC/DC converter is controlled to perform boosting or voltage reduction processing on direct current output by the power battery pack, and then the bidirectional vehicle-mounted charger OBC is controlled to perform inversion processing on the direct current output by the bidirectional DC/DC converter, so that the alternating current power equipment outside the automobile is supplied with power through the alternating current charging and discharging interface and the alternating current power equipment inside the automobile is supplied with power through the socket interface inside the automobile.

According to another aspect of the present invention, the present invention further provides a controller, which includes a memory, a processor and a computer program stored in the memory and running on the processor, wherein the processor reads the program in the memory and executes the steps in the charging and discharging method.

According to another aspect of the invention, the invention also provides an electric automobile which comprises the controller.

The invention has the beneficial effects that:

an alternating current charging and discharging interface, a direct current charging and discharging interface and an in-vehicle socket interface are integrated on a vehicle, so that the alternating current charging and discharging and direct current charging and discharging functions of the power battery pack can be realized. Particularly, the functional requirements of independent charging or discharging of a user can be met, and meanwhile, the DC charging and discharging interface is not electrified when AC charging and discharging are realized, and the AC charging and discharging interface is not electrified when DC charging and discharging are realized, so that the power utilization safety of the user using mode is ensured. Meanwhile, the first switch, the second switch and the third switch can be controlled to be switched on and off, and the requirement of a user on alternating current power utilization in a vehicle under special conditions is met. Due to the integrated control of the alternating current charging and discharging system and the direct current charging and discharging system, the direct current charging and discharging high-low voltage matching can be realized, the problems that the output voltage range of the OBC of the bidirectional vehicle-mounted charger is not compatible and the like are solved, and the problem that the output voltage of the direct current discharging is not matched is solved.

Drawings

Fig. 1 is a block diagram showing the structure of a charge and discharge system according to the present invention;

FIG. 2 is a schematic flow chart of a charging and discharging method according to the present invention;

description of reference numerals: 1. a power battery pack; 2. a bidirectional DC/DC converter; 3. a bidirectional vehicle-mounted charger OBC; 4. a low-voltage battery; 5. a control unit; 6. a detection unit; 7. a communication unit; 8. a communication interface; 12. an alternating current charge-discharge interface; 13. an in-vehicle socket interface; 14. a DC charge-discharge interface; s1, a first switch; s2, a second switch; s3, a third switch; k1, a fourth switch.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

Referring to fig. 1, the present invention provides a charge and discharge system including:

a power battery pack 1;

a bidirectional DC/DC converter 2 connected to the power battery pack 1;

a bidirectional on-board charger OBC3 connected to the bidirectional DC/DC converter 2;

the alternating current charging and discharging interface 12 is connected with the alternating current charging and discharging gun and is connected with the bidirectional vehicle-mounted charger OBC3 through a first switch S1;

a DC charge/discharge interface 14 for connecting to a DC charge/discharge gun, which is connected to the bidirectional DC/DC converter 2 through a second switch S2;

the in-vehicle socket interface 13 is used for connecting with in-vehicle electric equipment and is connected with the bidirectional vehicle-mounted charger OBC3 through a third switch S3;

the controller is respectively connected with the bidirectional DC/DC converter 2, the bidirectional vehicle-mounted charger OBC3, the first switch S1, the second switch S2 and the third switch S3;

the controller determines a charging and discharging mode of the electric vehicle according to the acquired working parameters, and controls the bidirectional DC/DC converter 2, the bidirectional on-board charger OBC3, the first switch S1, the second switch S2 and the third switch S3 according to the determined charging and discharging mode.

The power battery pack 1 is composed of a plurality of power battery monomers which are connected in series, electric quantity for the automobile to work is stored in the power battery pack, and the power battery pack 1 supplies power by means of an external power supply network or other electric automobiles.

The bidirectional DC/DC converter 2 is used to realize a boost (boost) or buck (buck) voltage, which chops a direct current into a square wave (pulse wave) through a switching tube, and then changes the voltage by adjusting a duty ratio (a ratio of a pulse width to a pulse period) of the square wave. Specifically, the bidirectional DC/DC converter 2 performs corresponding voltage processing according to the rated voltage of the power battery pack 1. For example, when the rated voltage of the power battery pack 1 is 500V, and when alternating current charging is performed, the bidirectional on-board charger OBC3 performs voltage boosting processing after rectification, so as to charge the power battery pack 1 through the bidirectional DC/DC converter 2; when the power battery pack 1 discharges the external alternating current, the bidirectional DC/DC converter 2 is required to perform voltage reduction processing, so as to output the direct current with the voltage of 220V to the bidirectional vehicle-mounted charger OBC 3. The bidirectional DC/DC converter 2 may be a product used in the prior art, such as a bidirectional buck-boost DC/DC converter structure disclosed in patent document "CN 207542996U".

The bidirectional vehicle-mounted charger OBC3 has the rectification and inversion capabilities, and when the power battery pack 1 is charged, the bidirectional vehicle-mounted charger OBC3 performs rectification; when the power battery pack 1 discharges outwards, the OBC3 carries out inversion. In the embodiment, the bidirectional vehicle-mounted charger OBC3 is only required to be a product in the prior art.

In this embodiment, three charging and discharging interfaces are provided, which are an ac charging and discharging interface 12, a dc charging and discharging interface 14, and an in-vehicle socket interface 13, where the ac charging and discharging interface 12 is an interface for connecting with an ac power grid or other external ac loads, and similarly, the dc charging and discharging interface 14 is an interface for connecting with a dc power grid or other external dc loads. The ac charging/discharging interface 12 and the dc charging/discharging interface 14 realize ac charging/discharging and dc charging/discharging of the vehicle. The in-vehicle socket interface 13 supplies power to the ac power consuming device in the vehicle by means of the power battery. The connection between the alternating current charging and discharging interface 12 and the alternating current charging gun and the connection between the direct current charging and discharging interface 14 and the direct current charging gun are set according to national standards. Similarly, the connection circuit between the ac discharge gun and the ac charging/discharging interface 12 is designed to have a structure similar to that between the ac discharge gun and the national standard, or the connection between the ac discharge gun and the ac charging/discharging interface 12 is implemented in a manner as provided in fig. 3 of patent publication "CN 108258761A", for example. Regardless of the arrangement, the ultimate goal is to make the resistance value at the CC2 detection point detected in the off-board ac discharge mode and the resistance value at the CC2 detection point detected in the ac charging mode different so that the controller can distinguish the correct operating mode of the electric vehicle.

Similarly, the connection between the dc discharge gun and the dc charging/discharging interface 14 is also provided to make the resistance value at the CC1 detection point detected in the vehicle-exterior dc discharge mode different from the resistance value at the CC1 detection point detected in the dc charging mode, so that the controller can distinguish the correct operation mode of the electric vehicle.

The in-vehicle socket interface 12 can be set as a common three-hole socket interface or a USB interface, so as to meet various small loads requiring charging, such as a common humidifier, a mobile phone, and a tablet in a vehicle.

The first to third switches S1 to S3 may be relays. The purpose of these switches is that the power battery pack 1 can only work in one state of charging or discharging, and when the power battery pack 1 is in the charging state, the discharging loop should be in the open circuit state; similarly, when the power battery pack 1 is in the discharging state, the charging circuit should be in the open state.

Referring to fig. 1, further includes:

a fourth switch K1 disposed between the in-vehicle socket interface 13 and the controller.

The fourth switch K1 is arranged to provide the controller with the power demand of the electric equipment in the vehicle, the fourth switch K1 can be opened and closed manually by the user, and the controller determines whether the charging demand of the electric equipment in the vehicle exists by detecting the open and closed state of the fourth switch K1. Referring to fig. 1, further includes:

and the communication interface 8 is used for being connected with the electric equipment outside the vehicle, and the communication interface 8 is connected with the controller.

The communication interface 8 is mainly connected to a gun head of an ac discharging gun and a gun head of a dc discharging gun, and the two types of guns send the loaded charging parameter requirements to the controller, such as parameters of charging voltage and charging current.

Preferably, referring to fig. 1, further comprising:

and the low-voltage storage battery 4 is respectively connected with the controller, the bidirectional DC/DC converter 2 and the bidirectional vehicle-mounted charger OBC 3.

The low-voltage battery 2 is mainly used for providing low-voltage wake-up signals for the loads to enable the loads to enter an operating state.

In the present application, the above-mentioned controller may be a power control system BMS, as shown in fig. 1, the controller specifically includes a control unit 5, a detection unit 6 and a communication unit 7, which are connected in sequence, the control unit 5 is configured to be connected to the low-voltage battery 4, the first switch S1, the second switch S2, the third switch S3, the bidirectional on-board charger OBC3 and the bidirectional DC/DC converter 2, the detection unit 6 is configured to detect CP signals, CC1 and CC2 signals and an on-off signal of the fourth switch K1, and the communication unit 7 forwards the charging demand information of the external power load received from the communication interface 8 to the detection unit 6 for analysis processing. The low voltage battery 4 supplies power to these units in the controller.

In summary, in the present embodiment, the ac charge/discharge interface 12, the dc charge/discharge interface 14, and the in-vehicle receptacle interface 13 are integrated into one vehicle, so that the ac charge/discharge and dc charge/discharge functions of the power battery pack 1 can be realized. Particularly, the functional requirements of independent charging or discharging of a user can be met, and meanwhile, the direct-current charging and discharging interface 14 is not electrified when alternating-current charging and discharging are realized, and the alternating-current charging and discharging interface 12 is not electrified when the direct-current charging and discharging are realized, so that the power utilization safety of the user using mode is ensured. Meanwhile, the first switch S1, the second switch S2 and the third switch S3 can be controlled to be opened and closed, and the requirement of a user on alternating current power utilization in a special case can be met. Due to the integrated control of the alternating current charging and discharging system and the direct current charging and discharging system, the direct current charging and discharging high-low voltage matching can be achieved, the problems that the output voltage range of the bidirectional vehicle-mounted charger OBC3 is not compatible and the like are solved, and the problem that the output voltage of the direct current discharging is not matched is solved.

According to another aspect of the present invention, the present invention also provides a charging and discharging method applied to the above charging and discharging system, wherein the method is mainly executed by means of a battery management system BMS as a controller, and with reference to fig. 2, the method specifically includes:

step 101, obtaining working parameter information detected from each vehicle-mounted interface, wherein the vehicle-mounted interface comprises: an alternating current charge and discharge interface 12, a direct current charge and discharge interface 14, an in-vehicle socket interface 13 and a communication interface 8.

The working parameter information detected from each vehicle-mounted interface is as follows: a resistance value of CC2 and a CP voltage value detected from the ac charging/discharging interface 12, or a resistance value of CC1 detected from the dc charging/discharging interface 14, or an on/off signal of a fourth switch K1 connected to the in-vehicle socket interface 13, or a charging signal of electric equipment external to the vehicle detected from the communication interface 8 and a resistance value of CC2 detected from the ac charging/discharging interface 12, or a charging signal of electric equipment external to the vehicle detected from the communication interface 8 and a resistance value of CC1 detected from the dc charging/discharging interface 14, or an on/off signal of a fourth switch K1 connected to the in-vehicle socket interface 13, a charging signal of electric equipment external to the vehicle detected from the communication interface 8, and a resistance value of CC2 detected from the ac charging/discharging interface 12.

Step 102, determining a charging and discharging mode of the electric automobile according to the working parameter information;

if the resistance value of the CC2 detected from the ac charging/discharging interface 12 is R1 and the CP voltage value is U1, it is determined that the electric vehicle is in the ac charging mode, where the ac charging mode is a mode in which the power battery pack 1 is charged through the ac charging/discharging interface 12. Wherein, the resistance value of R1 and the voltage value of U1 are established according to national standard. The resistor R1 and the CP voltage value U1 indicate that the ac charging gun has established a connection with the ac charge/discharge interface 12 and the power supply grid.

If the resistance value of the CC1 detected from the DC charging and discharging interface 14 is R3, the electric vehicle is determined to be in a DC charging mode, and the DC charging mode is a mode of charging the power battery pack through the DC charging and discharging interface 14. Wherein, the resistance values of R3 and R1 are different, and the resistance value of R3 is determined according to national standard setting.

If the on-off signal of the fourth switch K1 connected to the in-vehicle socket interface 13 indicates that the fourth switch K1 is pressed for the first time, it is determined that the electric vehicle is in the in-vehicle ac discharging mode, where the power battery pack 1 supplies ac power to the in-vehicle ac electric equipment through the in-vehicle socket interface 13. The first pressing of the fourth switch K1 means the first pressing of the fourth switch K1 after the entire vehicle is powered on and initialized. When the fourth switch K1 is turned off, the power battery does not discharge to the outside, so that the socket interface 13 in the vehicle is ensured to be uncharged, and the power utilization safety is ensured.

If the charging signal of the external electric equipment detected from the communication interface 8 is an alternating current charging demand signal of the external alternating current electric equipment and the resistance value of the CC2 detected from the alternating current charging and discharging interface 12 is R2, it is determined that the electric vehicle is in an external alternating current discharging mode, and the external alternating current discharging mode is a mode of supplying alternating current to the external alternating current electric equipment through the alternating current discharging interface 12. The resistance value of R2 is different from the resistance values of R1 and R3, and the vehicle-exterior electric device detected from the communication interface 8 is usually an ac power grid or other vehicle-exterior ac electric devices.

If the charging signal of the vehicle external electric equipment detected from the communication interface 8 is a direct current charging demand signal of the vehicle external direct current electric equipment and the resistance value of the CC1 detected from the direct current charging and discharging interface 14 is R4, it is determined that the electric vehicle is in the vehicle external direct current discharging mode, and the vehicle external direct current discharging mode is a mode of supplying direct current to the vehicle external direct current electric equipment through the direct current charging and discharging interface 14. The resistance value of R4 is different from the resistance values of R1 to R3, and the vehicle-external electric device detected from the communication interface 8 is usually a dc power grid or other vehicle-external dc electric devices (such as an electric vehicle).

If the on-off signal of the fourth switch K1 connected to the in-vehicle socket interface 13 indicates that the fourth switch K1 is pressed for the first time, the charging signal of the external electric device detected from the communication interface 8 is the ac charging demand signal of the external ac electric device, and the resistance value of the CC2 detected from the ac charging/discharging interface 12 is R2, it is determined that the electric vehicle is in the in-vehicle and external synchronous ac discharging mode, which is a mode in which the external ac electric device is supplied with ac power through the ac discharging interface 12 and the internal ac electric device is supplied with ac power through the in-vehicle socket interface 13.

In order to facilitate manufacturers to manufacture corresponding charge and discharge devices in a unified manner, the charge and discharge devices of different manufacturers have universality, but the embodiment of the invention is not limited to the above exemplary resistance values of R2 and R4.

In this embodiment, since the power battery pack 1 is charged by an ac charging method and a dc charging method, theoretically, the ac charging and the dc charging can be performed simultaneously; however, in actual operation, since the DC power supply and the ac power supply voltage are not always the same, and the bidirectional DC/DC converter 2 cannot perform the step-up or step-down processing on two different power supply voltages when operating, in this embodiment, the DC charging is prohibited when the ac charging is performed, and the ac charging is prohibited when the DC charging is performed; if the controller judges that the alternating current charging mode and the direct current charging mode are met, the alternating current charging mode or the direct current charging mode can be used as a priority charging mode, and the switch corresponding to the other charging mode is forbidden to be closed. Similarly, during ac discharge or dc discharge, there may be a difference between the ac discharge operating parameter requirement and the dc discharge operating parameter requirement, so that during ac discharge, dc discharge is prohibited; when the dc discharge is performed, the ac discharge is prohibited.

103, according to the charging and discharging mode, sending control signals to the bidirectional DC/DC converter 2, the bidirectional on-board charger OBC3, the first switch S1, the second switch S2, and the third switch S3 to operate according to an instruction corresponding to the charging and discharging mode.

Step 103 specifically comprises:

if the electric automobile is in an alternating current charging mode, the first switch S1 is controlled to be closed, the second switch S2 and the third switch S3 are controlled to be disconnected, the bidirectional vehicle-mounted charger OBC3 is controlled to rectify alternating current input through the alternating current charging and discharging interface 12, and the bidirectional DC/DC converter 3 is controlled to boost or reduce voltage of the rectified direct current to charge the power battery pack 1. In the process of alternating current charging, if the controller receives detection signals at other interfaces, in order to ensure the safe charging of the power battery pack 1, the controller controls the corresponding switches (the second switch S2 and the third switch S3) to be turned off.

If the electric automobile is in a direct current charging mode, the second switch S2 is controlled to be closed, the first switch S1 and the third switch S3 are controlled to be opened, and the bidirectional DC/DC converter 2 is controlled to perform boosting or voltage reduction processing on direct current output by the bidirectional vehicle-mounted charger OBC3 so as to charge the power battery pack 1. Similarly, in the process of charging the direct current, if the controller receives detection signals at other interfaces, in order to ensure that the power battery pack 1 is charged safely, the controller controls the corresponding switches (the first switch S1 and the third switch S3) to be turned off.

If the electric automobile is in an in-vehicle alternating current discharging mode, the third switch S3 is controlled to be closed, the first switch S1 and the second switch S2 are controlled to be opened, the bidirectional DC/DC converter 2 is controlled to perform boosting or reducing voltage processing on the direct current output by the power battery pack 1, and then the bidirectional vehicle-mounted charger OBC3 is controlled to perform inversion processing on the direct current output by the bidirectional DC/DC converter 2, so that power is supplied to in-vehicle alternating current electric equipment through the in-vehicle socket interface 13.

If electric automobile is the outer alternating current discharge mode of car, then control first switch S1 is closed second switch S2 with third switch S3 disconnection, control two-way DC/DC converter 2 is right the direct current of power battery package 1 output is carried out and is stepped up or step-down and handle, and the controlate is again two-way vehicle-mounted machine OBC3 is right the direct current of two-way DC/DC converter 2 output carries out the contravariant and handles to pass through alternating current charge and discharge interface 12 is the outer electric equipment power supply of interchange of car.

If the electric automobile is in an external direct current discharging mode, the second switch S2 is controlled to be closed, the first switch S1 and the third switch S3 are controlled to be disconnected, the bidirectional DC/DC converter 2 is controlled to boost or reduce the voltage of the direct current output by the power battery pack 1, and the bidirectional vehicle-mounted charger OBC3 transfers the direct current processed by the bidirectional DC/DC converter 2 to the direct current charging and discharging interface 14 so as to supply power for external direct current electric equipment through the direct current charging and discharging interface 14.

If the electric automobile is in an inside and outside synchronous alternating current discharging mode, the first switch S1 and the third switch S3 are controlled to be closed, the second switch S2 is controlled to be opened, the bidirectional DC/DC converter 2 is controlled to perform boosting or voltage reduction processing on the direct current output by the power battery pack 1, and then the bidirectional vehicle-mounted charger OBC3 is controlled to perform inversion processing on the direct current output by the bidirectional DC/DC converter 2, so that the alternating current charging and discharging interface 12 is used for supplying power to the external alternating current electric equipment and the internal socket interface 13 is used for supplying power to the internal alternating current electric equipment. Under this condition, the rated voltages of the ac electric devices outside the vehicle and the ac electric devices inside the vehicle should be the same, for example, 220V.

Referring to fig. 1, the charging and discharging system performs different mode control and output according to specific ac and dc charging and discharging requirements.

Controlling alternating current charging: the alternating current charging and discharging interface 12 is connected with a power grid alternating current power supply device, the detection unit 6 detects that a PWM signal of a CP and a resistance value of a CC2 are R1, the detection unit 6 confirms that the alternating current charging mode is the alternating current charging mode, the detection unit 6 transmits information to the control unit 5 through an internal circuit, and the control unit 5 controls the first switch S1 to be closed, controls the bidirectional vehicle-mounted charger OBC3 to output according to a specified voltage, controls the bidirectional DC/DC converter 2 to output according to a specified voltage, and realizes charging of a battery pack.

External AC discharge control: the alternating current charging and discharging interface 12 is connected with an alternating current electric device outside the vehicle, the requirement information of the electricity consumption outside the vehicle is transmitted to the communication unit 7 through the external communication interface 8, the communication unit 7 transmits the information to the detection unit 6, meanwhile, the detection unit 6 detects that the resistance value of CC2 is R2, the information is confirmed to be an alternating current discharging mode outside the vehicle, the detection unit 6 transmits the information to the control unit 5 through an internal circuit, the control unit 2 controls the bidirectional DC/DC converter 2 to convert the voltage of the power battery pack 1 into direct current voltage output specified by the bidirectional vehicle OBC3, the bidirectional vehicle OBC3 is controlled to convert the direct current voltage into the required alternating current voltage output, the control unit 5 controls the first switch S1 to be closed, and the alternating current electric device outside the vehicle is supplied with power through the alternating current.

Controlling the alternating current discharge in the vehicle: the in-vehicle socket interface 13 is connected with in-vehicle alternating current electric equipment, the detection unit 6 detects that a fourth switch K1 signal is pressed for the first time, the detection unit 6 transmits information to the control unit 5 through an internal circuit, the control unit controls the bidirectional DC/DC converter 2 to convert the voltage of the power battery pack 1 into direct current voltage output specified by the bidirectional vehicle-mounted charger OBC3, the bidirectional vehicle-mounted charger OBC3 is controlled to convert direct current high voltage into 220Vac alternating current output, the third switch S3 is controlled to be closed, and the power utilization requirements of the in-vehicle electric equipment of a user are met through the in-vehicle socket interface. The detection unit 6 detects that the K1 signal is pressed again, the detection unit 6 transmits information to the control unit 5 through an internal circuit, the control unit 5 controls the bidirectional DC/DC converter 2 to stop working, controls the bidirectional OBC3 to stop working, and controls the third switch S3 to be switched off to cut off the alternating current discharge output in the vehicle.

And (3) controlling the simultaneous alternating current discharge inside and outside the vehicle: and simultaneously detecting the requirement of the alternating current discharge outside the vehicle inside the vehicle, and simultaneously executing the alternating current discharge control outside the vehicle and the alternating current discharge control mode inside the vehicle.

Controlling direct current charging: the direct current charge and discharge interface 14 is connected with a direct current charging device outside the vehicle, the detection unit 6 detects that the resistance value of the CC1 is R3, the detection unit 6 confirms that the direct current charging mode is adopted, the detection unit 6 transmits information to the control unit 5 through an internal circuit, and the control unit 5 controls the second switch S2 to be closed and controls the bidirectional DC/DC converter 2 to output the voltage according to the specified voltage, so that the battery pack is charged.

And D, direct current discharge control: the direct current charge and discharge interface 14 is connected with an external direct current charging vehicle, external electricity consumption requirement information (transmitted to the communication unit 7 through the external communication interface 8, the communication unit 7 transmits the information to the detection unit 6, meanwhile, the detection unit 6 detects that the resistance value of the CC1 is R4, the direct current discharge mode is confirmed, the detection unit 6 transmits the information to the control unit 5 through an internal circuit, the control unit 5 controls the second switch S2 to be closed, and controls the bidirectional DC/DC converter 2 to output according to the specified voltage, so that direct current charging of other vehicles is realized.

According to another aspect of the present invention, the present invention further provides a controller, which includes a memory, a processor and a computer program stored in the memory and running on the processor, wherein the processor reads the program in the memory and executes the steps in the charging and discharging method.

According to another aspect of the invention, the invention also provides an electric automobile which comprises the controller.

The above-described embodiments illustrate only some of the one or more embodiments of the invention, but those skilled in the art will recognize that the invention can be embodied in many other forms without departing from the spirit or scope of the invention. Accordingly, the present examples and embodiments are to be considered as illustrative and not restrictive, and various modifications and substitutions may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.