Charging circuit, charging control method and electric vehicle

Abstract

The invention discloses a charging circuit, a charging control method and an electric vehicle. The charging circuit comprises a main loop, a first branch circuit and a second branch circuit, the main loop comprises a pre-charging resistor and a main anode contactor which are connected with the anode of the battery pack; the first branch circuit is connected with the main loop and the first charging port and comprises a first anode contactor and a first pre-charging contactor which are connected with the anode of the first charging port; the first pre-charging contactor is connected in series with the pre-charging resistor; the first anode contactor is connected between the battery pack and the first charging port, and is connected in parallel with the pre-charging resistor and the main anode contactor; and the second branch is connected with the main loop and the second charging port and comprises a second anode contactor connected with the anode of the second charging port, and the second anode contactor is connected with the pre-charging resistor and the main anode contactor in series. The pre-charging of the second branch circuit is realized by multiplexing the main anode contactor of the main loop, one pre-charging contactor is reduced, the volume of parts is reduced, the cost of the parts is reduced, and the spatial layout is optimized.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and more particularly, to a charging circuit, a charging control method, and an electric vehicle. Background Art

[0002] With the continuous increase in the battery capacity of vehicles, some high-power electric vehicles basically have the dual-gun charging function. At present, the charging circuit scheme for dual-gun charging generally parallels an identical charging circuit on the basis of the original charging circuit. The component structure is complex, the degree of reuse of the charging circuit is low, which affects the space layout, and at the same time increases the component cost. Summary of the Invention

[0003] A series of simplified concepts are introduced in the Summary of the Invention section, which will be further described in detail in the Detailed Description section. The Summary of the Invention section of the present invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the protection scope of the claimed technical solution.

[0004] In view of the deficiencies of the prior art, a first aspect of an embodiment of the present invention provides a charging circuit, which includes:

[0005] A main circuit connected to the battery pack, the main circuit including a pre-charge resistor 304 and a main positive contactor 301 both connected to the positive electrode of the battery pack;

[0006] A first branch connected to the main circuit and a first charging port, the first branch including a first positive contactor 305 and a first pre-charge contactor 307 both connected to the positive electrode of the first charging port; wherein, the first pre-charge contactor 307 is in series with the pre-charge resistor 304; the first positive contactor 305 is connected between the battery pack and the first charging port, and is in parallel with both the pre-charge resistor 304 and the main positive contactor 301;

[0007] A second branch connected to the main circuit and a second charging port, the second branch including a second positive contactor 308 connected to the positive electrode of the second charging port, the second positive contactor 308 being in series with both the pre-charge resistor 304 and the main positive contactor 301.

[0008] In one embodiment, when the second positive contactor 308 is closed and the main positive contactor 301 is open, the positive electrode of the second charging port can be conducted with the positive electrode of the battery pack through the pre-charge resistor 304.

[0009] In one embodiment, when the first pre-charge contactor 307 is open and the first positive contactor 305 is closed, the positive electrode of the first charging port can be conducted with the positive electrode of the battery pack.

[0010] In one embodiment, when the first pre-charge contactor 307 is closed and the first positive contactor 305 is open, the positive electrode of the first charging port can be electrically connected to the positive electrode of the battery pack through the pre-charge resistor 304.

[0011] In one embodiment, the first branch further includes a contactor 303 connected between the first pre-charge contactor 307 and the main positive contactor 301, and the contactor 303 is connected in parallel with the pre-charge resistor 304.

[0012] In one embodiment, when the first pre-charge contactor 307 is closed and both the first positive contactor 305 and the contactor 303 are open, the positive electrode of the first charging port can be electrically connected to the positive electrode of the battery pack through the pre-charge resistor 304.

[0013] In one embodiment, the contactor 303 is further connected between the pre-charge resistor 304 and the second positive contactor 308.

[0014] In one embodiment, when both the second positive contactor 308 and the contactor 303 are closed and the main positive contactor 301 is open, the positive electrode of the second charging port can be electrically connected to the positive electrode of the battery pack through the pre-charge resistor 304.

[0015] In one embodiment, the first branch further includes a first negative contactor 306, and the first negative contactor 306 is connected between the negative electrode of the battery pack and the negative electrode of the first charging port; the second branch further includes a second negative contactor 309, and the second negative contactor 309 is connected between the negative electrode of the battery pack and the negative electrode of the second charging port.

[0016] In one embodiment, the main circuit further includes a main negative contactor 302 connected to the negative electrode of the battery pack; the main negative contactor 302 is connected between the negative electrode of the battery pack and the first negative contactor 306; and / or, the main negative contactor 302 is connected between the negative electrode of the battery pack and the second negative contactor 309.

[0017] A second aspect of the embodiments of the present invention provides a charging control method, which is used for the charging circuit as described above, and the method includes:

[0018] When pre-charging is performed based on the second charging port, control the second positive contactor 308 to be closed and the main positive contactor 301 to be open, so that the positive electrode of the second charging port is electrically connected to the positive electrode of the battery pack through the pre-charge resistor 304;

[0019] After completing the pre-charging based on the second charging port, control the main positive contactor 301 to close, so that the positive pole of the second charging port is conducted with the positive pole of the battery pack.

[0020] In one embodiment, the method further includes:

[0021] When pre-charging based on the first charging port, control the first pre-charge contactor 307 to close and the first positive contactor 305 to open, so that the positive pole of the first charging port is conducted with the positive pole of the battery pack through the pre-charge resistor 304;

[0022] After completing the pre-charging based on the first charging port, control the first pre-charge contactor 307 to open and the first positive contactor 305 to close, so that the positive pole of the first charging port is conducted with the positive pole of the battery pack.

[0023] A third aspect of the embodiments of the present invention provides an electric vehicle, and the electric vehicle includes the charging circuit as described above.

[0024] The charging circuit, charging control method and electric vehicle of the embodiments of the present invention realize the pre-charge of the second branch by multiplexing the main positive contactor of the main circuit, thereby reducing one pre-charge contactor, reducing the volume of parts, reducing the part cost, and optimizing the spatial structure of parts, making the electric vehicle more advantageous in spatial layout. Description of the Drawings

[0025] By describing the embodiments of the present invention in more detail in conjunction with the drawings, the above and other objects, features and advantages of the present invention will become more obvious. The drawings are used to provide a further understanding of the embodiments of the present invention, and constitute a part of the specification, and are used to explain the present invention together with the embodiments of the present invention, and do not constitute a limitation to the present invention. In the drawings, the same reference numerals generally represent the same components or steps.

[0026] Figure 1 is a schematic diagram of an existing charging circuit;

[0027] Figure 2 is a schematic diagram of a charging control process based on the existing charging circuit;

[0028] Figure 3 is a schematic diagram of a charging circuit according to an embodiment of the present invention;

[0029] Figure 4 is a schematic diagram of a charging circuit according to another embodiment of the present invention;

[0030] Figure 5 is a schematic diagram of a charging control process based on the charging circuit of the embodiments of the present invention;

[0031] Figure 6 It is a schematic diagram of another charging control process of the charging circuit according to an embodiment of the present invention;

[0032] Figure 7 It is a schematic flowchart of the charging control method according to an embodiment of the present invention. Detailed implementation manners

[0033] In order to make the objectives, technical solutions and advantages of the present application more apparent, the exemplary embodiments according to the present application will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. It should be understood that the present application is not limited by the exemplary embodiments described herein. Based on the embodiments of the present application described in the present application, all other embodiments obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present application.

[0034] In the following description, numerous specific details are given to provide a more thorough understanding of the present application. However, it is obvious to those skilled in the art that the present application can be implemented without one or more of these details. In other examples, some well-known technical features are not described to avoid confusion with the present application.

[0035] It should be understood that the present application can be implemented in different forms and should not be construed as limited to the embodiments presented herein. On the contrary, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of the present application to those skilled in the art.

[0036] The purpose of the terms used herein is only to describe specific embodiments and is not a limitation of the present application. When used herein, the singular forms "a", "an" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "comprising" and / or "including", when used in this specification, determine the presence of the described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups. When used herein, the term "and / or" includes any and all combinations of the related listed items.

[0037] First, refer to Figure 1 , Figure 1A charging circuit for dual-gun charging is shown. Among them, the main circuit includes a main positive contactor 101, a main negative contactor 102, a main pre-charge contactor 103, and a pre-charge resistor 104. The first charging circuit and the second charging circuit are connected in parallel to the main circuit. The first charging port is connected to the first charging circuit, and the first charging circuit includes a first positive contactor 105, a first negative contactor 106, and a first pre-charge contactor 107; the second charging port is connected to the second charging circuit, and the second charging circuit includes a second positive contactor 108, a second negative contactor 109, and a second pre-charge contactor 110. The first pre-charge contactor 107, the second pre-charge contactor 110, and the main pre-charge contactor 102 are respectively connected to the pre-charge resistor 104.

[0038] Figure 2 shows a charging control method based on Figure 1 the charging circuit shown. After the charging process starts, if the vehicle is not powered on at high voltage, the main circuit needs to be pre-charged first. Specifically, first close the main negative contactor 102 and the main pre-charge contactor 103, and the pre-charge branch of the main circuit containing the pre-charge resistor 104 is turned on to pre-charge the main circuit. After the main circuit pre-charge is completed, close the main positive contactor 101 and open the main pre-charge contactor 103, and the charging circuit of the main circuit is turned on.

[0039] Next, pre-charge the charging port. Taking the first charging port as an example, first close the first negative contactor 106 and the first pre-charge contactor 105, and the pre-charge branch of the first circuit containing the pre-charge resistor 104 is turned on to pre-charge the first charging port. Then, close the first positive contactor 104 and open the first pre-charge contactor 106, and the charging circuit of the first circuit is turned on, and the battery pack is charged through the first charging port. After charging is completed, open the first positive contactor 104, the first negative contactor 105, the main positive contactor 101, and the main negative contactor 102 to end the charging process.

[0040] Figure 1 In the charging circuit shown, the main circuit, the first circuit, and the second circuit respectively include their own pre-charge contactors, the structure of the parts is complex, which affects the space layout; and the degree of loop reuse is low, resulting in an increase in the cost of parts.

[0041] In view of the above problems, the embodiments of the present invention propose a charging circuit, a charging control method, and an electric vehicle, which reuse the main positive contactor of the main circuit to realize the pre-charge of the second branch, thereby reducing a pre-charge contactor, reducing the space structure of the parts, and the implementation method is simple, low-cost, and the control method is flexible and advanced.

[0042] To fully understand this application, detailed structures will be presented in the following description to illustrate the technical solutions proposed by this application. The optional embodiments of this application are described in detail below. However, in addition to these detailed descriptions, this application may also have other implementation manners.

[0043] First, refer to Figure 3 to describe the charging circuit proposed in the embodiments of the present invention. The charging circuit in the embodiments of the present invention includes: a main circuit, a first branch, and a second branch; wherein, the main circuit is connected to the battery pack, and the main circuit includes a pre-charge resistor 304 and a main positive contactor 301 that are both connected to the positive electrode of the battery pack; the first branch is connected to the main circuit and the first charging port, and the first branch includes a first positive contactor 305 and a first pre-charge contactor 307 that are both connected to the positive electrode of the first charging port; the first pre-charge contactor 307 is connected in series with the pre-charge resistor 304; the first positive contactor 305 is connected between the battery pack and the first charging port, and is connected in parallel with both the pre-charge resistor 304 and the main positive contactor 301; the second branch is connected to the main circuit and the second charging port, and the second branch includes a second positive contactor 308 connected to the positive electrode of the second charging port, and the second positive contactor 308 is connected in series with both the pre-charge resistor 304 and the main positive contactor 301.

[0044] Exemplarily, the main circuit includes a main positive contactor 301 and a pre-charge resistor 304. One end of the main circuit is connected to the battery pack, that is, the power battery of the vehicle; the other end is connected to the Power Domain Controller (PDC), as well as the On-Board Charger (OBC) and the DC Converter (LC), etc. Among them, the Power Domain Controller is an intelligent power-train management unit that can realize transmission management, engine management, battery monitoring, alternator regulation, etc. The On-Board Charger and the DC Converter can be used to provide voltage and charge the battery. Specifically, both the pre-charge resistor 304 and the main positive contactor 301 are connected to the positive electrode of the battery pack. In some embodiments, the main circuit may further include a main negative contactor 302. Refer to Figure 3 , the main positive contactor 301 is connected to the positive electrode of the battery pack, and the main negative contactor 302 is connected to the negative electrode of the battery pack.

[0045] When setting the first branch, refer to Figure 3 and Figure 4 , the first branch is connected to the main circuit and the first charging port. Among them, the first charging port includes, but is not limited to, a DC charging port, which is connected to the battery pack through the first branch and the main circuit, so as to charge the battery pack, or the battery pack pre-charges the first charging port. As Figure 3 and Figure 4As shown, the first branch includes a first positive contactor 305 and a first pre-charge contactor 307. Both the first positive contactor 305 and the first pre-charge contactor 307 are connected to the positive pole of the first charging port. And the first pre-charge contactor 307 is connected in series with a pre-charge resistor 304. The first positive contactor 305 is connected between the battery pack and the first charging port, and is in parallel with both the pre-charge resistor 304 and the main positive contactor 301.

[0046] Exemplarily, referring to Figure 3 and Figure 4 , when the first pre-charge contactor 307 is closed and the first positive contactor 305 is open, the positive pole of the first charging port can be electrically connected to the positive pole of the battery pack through the pre-charge resistor 304, facilitating pre-charging between the first charging port and the battery pack. When specifically performing pre-charging based on the first charging port, referring to Figure 3 and Figure 4 , control the first pre-charge contactor 307 to close and the first positive contactor 305 to open, so that the positive pole of the first charging port is electrically connected to the positive pole of the battery pack through the pre-charge resistor 304. After the negative pole of the first charging port is also electrically connected to the negative pole of the battery pack, pre-charging can be performed between the first charging port and the battery pack.

[0047] Exemplarily, referring to Figure 3 and Figure 4 , when the first pre-charge contactor 307 is open and the first positive contactor 305 is closed, the positive pole of the first charging port can be electrically connected to the positive pole of the battery pack, facilitating charging between the first charging port and the battery pack. During the application process, after completing pre-charging based on the first charging port, the first pre-charge contactor 307 can be controlled to open and the first positive contactor 305 to close, so that the positive pole of the first charging port is electrically connected to the positive pole of the battery pack. After the negative pole of the first charging port is also electrically connected to the negative pole of the battery pack, charging can be performed between the first charging port and the battery pack. Thus, normal charging based on the first charging port is achieved.

[0048] When setting up the second branch, referring to Figure 3 and Figure 4 , the second branch connects the main circuit and the second charging port. When setting up the second charging port, the second charging port includes, but is not limited to, an AC / DC integrated charging port, which is connected to the battery pack through the second branch and the main circuit, thereby charging the battery pack or pre-charging the second charging port by the battery pack. As Figure 3 and Figure 4 shown, the second branch includes a second positive contactor 308 connected to the positive pole of the second charging port. The second positive contactor 308 is connected in series with both the pre-charge resistor 304 and the main positive contactor 301.

[0049] Exemplarily, referring to Figure 3 and Figure 4, when the second positive contactor 308 is closed and the main positive contactor 301 is open, the positive electrode of the second charging port can be conducted to the positive electrode of the battery pack through the pre-charge resistor 304, so as to facilitate pre-charging between the second charging port and the battery pack. When specifically pre-charging based on the second charging port, refer to Figure 3 and Figure 4 , control the second positive contactor 308 to be closed and the main positive contactor 301 to be open, so that the positive electrode of the second charging port is conducted to the positive electrode of the battery pack through the pre-charge resistor 304. After the negative electrode of the second charging port is also conducted to the negative electrode of the battery pack, pre-charging can be carried out between the second charging port and the battery pack.

[0050] Exemplarily, refer to Figure 3 and Figure 4 , when both the main positive contactor 301 and the second positive contactor 308 are closed, the positive electrode of the second charging port can be conducted to the positive electrode of the battery pack, which is convenient for charging between the second charging port and the battery pack. During the application process, after completing the pre-charging based on the second charging port, the main positive contactor 301 can be controlled to be closed, so that the positive electrode of the second charging port is conducted to the positive electrode of the battery pack. After the negative electrode of the second charging port is also conducted to the negative electrode of the battery pack, charging can be carried out between the second charging port and the battery pack. Thus, normal charging based on the second charging port is realized.

[0051] Comparing Figure 1 it can be seen that in a general charging circuit, the main positive contactor is arranged between the first positive contactor and the battery pack, and only when both the main positive contactor and the first positive contactor are conducted can the first charging loop be conducted. Compared with the general charging circuit, the connection point of the first positive contactor 305 of the embodiment of the present invention to the main circuit is arranged at the front end of the main positive contactor 301, so that the conduction of the first branch is not affected by the opening and closing of the main positive contactor 301, and thus the control method is more flexible.

[0052] The second branch of the embodiment of the present invention does not include a pre-charge contactor, but realizes the pre-charge of the second charging port by controlling the opening or closing of the main positive contactor 301 of the main circuit, thereby reducing one pre-charge contactor, reducing the volume of the parts, lowering the part cost, optimizing the spatial structure of the parts, and making the electric vehicle more advantageous in spatial layout.

[0053] In a more optimal embodiment, refer to Figure 3 and Figure 4 , the first branch may further include: a contactor 303 connected between the first pre-charge contactor 307 and the main positive contactor 301, and the contactor 303 is connected in parallel with the pre-charge resistor 304. By setting the contactor 303, when pre-charging between the first charging port and the battery pack, it is not necessary to disconnect the main positive contactor 301, so that the pre-charge of the first branch does not affect the discharge of the battery pack.

[0054] Exemplarily, during the pre-charging process of the battery pack based on the first charging port, the first pre-charging contactor 307 can be closed, and the first positive contactor 305 and the contactor 303 are both opened. When the first pre-charging contactor 307 is closed and the first positive contactor 305 and the contactor 303 are both opened, the positive electrode of the first charging port can be conducted with the positive electrode of the battery pack through the pre-charge resistor 304, so as to realize pre-charging between the first charging port and the battery pack without opening the main positive contactor 301. That is, during the pre-charging process between the first charging port and the battery pack, the main positive contactor 301 can be either opened or closed, so that it can be selected and configured according to whether the vehicle needs to discharge.

[0055] Of course, in other embodiments, the contactor 303 may not be provided, and a wire may be directly connected between the first pre-charging contactor 307 and the main positive contactor 301. At this time, during the pre-charging process of the battery pack based on the first charging port, the first pre-charging contactor 307 needs to be closed, and the first positive contactor 305 and the main positive contactor 301 are both opened, which will affect the external discharge of the battery pack. That is, during the pre-charging process between the first charging port and the battery pack at this time, the external discharge of the battery pack needs to be stopped.

[0056] Exemplarily, refer to Figure 3 and Figure 4 , the contactor 303 is also connected between the pre-charge resistor 304 and the second positive contactor 308. Thus, during the pre-charging process based on the second charging port and the battery pack, the second positive contactor 308 and the contactor 303 can be both closed, and the main positive contactor 301 is opened. When the second positive contactor 308 and the contactor 303 are both closed and the main positive contactor 301 is opened, the positive electrode of the second charging port can be conducted with the positive electrode of the battery pack through the pre-charge resistor 304, so as to improve the safety redundancy. After completing the pre-charging between the second charging port and the battery pack, the main positive contactor 301 can be closed, and the contactor 303 can be either opened or closed to enable the second charging port to charge the battery pack normally. Of course, in other embodiments, the pre-charge resistor 304 and the second positive contactor 308 can be directly connected by a wire without passing through the contactor 303.

[0057] When realizing the disconnection and conduction control between the negative electrode of the battery pack and the negative electrode of the charging port, various methods can be adopted. Exemplarily, refer to Figure 3 and Figure 4, the first branch may further include a first negative contactor 306, and the first negative contactor 306 is connected between the negative electrode of the battery pack and the negative electrode of the first charging port; the second branch may further include a second negative contactor 309, and the second negative contactor 309 is connected between the negative electrode of the battery pack and the negative electrode of the second charging port. By adding the first negative contactor 306 and the second negative contactor 309 at the negative electrode of each of the first charging port and the second charging port, the safety redundancy can be improved. Of course, in other embodiments, the main negative contactor 302 in the main circuit can control the conduction or disconnection between the negative electrode of the battery pack and the negative electrode of each of the first charging port and the second charging port.

[0058] Exemplarily, referring to Figure 3 and Figure 4 , when the main circuit further includes a main negative contactor 302 connected to the negative electrode of the battery pack, the connection manner between the main negative contactor 302 and the first negative contactor 306 and the second negative contactor 309 can adopt various ways. Exemplarily, the main negative contactor 302 can be connected between the negative electrode of the battery pack and the first negative contactor 306. And / or, the main negative contactor 302 is connected between the negative electrode of the battery pack and the second negative contactor 309. As Figure 3 shown, the main negative contactor 302 is connected between the negative electrode of the battery pack and the first negative contactor 306, and the main negative contactor 302 is connected between the negative electrode of the battery pack and the second negative contactor 309. As Figure 4 shown, the negative electrode of the battery pack and the first negative contactor 306 are not connected through the main negative contactor 302, that is, they are directly connected between the negative electrode of the battery pack and the first negative contactor 306. And the main negative contactor 302 is connected between the negative electrode of the battery pack and the second negative contactor 309. Of course, in other embodiments, only the first negative contactor 306 and the second negative contactor 309 can be provided, and the main negative contactor 30 connected to the negative electrode of the battery pack is not provided in the main circuit, so that the first negative contactor 306 and the second negative contactor 309 are respectively connected to the negative electrode of the battery pack.

[0059] Next, in combination with Figure 3 and Figure 4 exemplarily introduce some specific connection manners. In Figure 3In the example, the first end of the main positive contactor 301 is connected to the positive electrode of the battery pack. Exemplarily, a main circuit fuse is also connected between the main positive contactor 301 and the battery pack. The first end of the pre-charge resistor 304 is connected to the positive electrode of the battery pack and the first end of the main positive contactor 301. The second end of the pre-charge resistor 304 is connected to the first end of the contactor 303. The second end of the contactor 303 is connected to the second end of the main positive contactor 301. The first end of the main negative contactor 302 is connected to the negative electrode of the battery pack. Exemplarily, a battery sampling and execution unit (BASU) is also connected between the main negative contactor 302 and the battery pack.

[0060] In some embodiments, the first positive contactor 305 is connected in parallel with the main positive contactor 301, that is, one of the connection points between the first branch and the main circuit is provided at the front end of the main positive contactor 301, that is, the end close to the battery pack. Specifically, the first end of the first positive contactor 305 is connected to the positive electrode of the battery pack, the first end of the pre-charge resistor 304, and the first end of the main positive contactor 301; the second end of the first positive contactor 305 is connected to the positive electrode of the first charging port. The first end of the first pre-charge contactor 307 is connected to the second end of the pre-charge resistor 304; the second end of the first pre-charge contactor 307 is connected to the first end of the first charging port, so that the pre-charge resistor 304 and the first pre-charge contactor 307 are connected in series, and both are connected in parallel with the first positive contactor 305. The first end of the first negative contactor 306 is connected to the second end of the main negative contactor 302, and the second end of the first negative contactor 306 is connected to the negative electrode of the first charging port. Exemplarily, a DC current Hall is also connected between the first negative contactor 306 and the first charging port.

[0061] Comparison Figure 1 It can be seen that in a general charging circuit, the main positive contactor is arranged between the first positive contactor and the battery pack, and the first charging circuit can be conducted only when both the main positive contactor and the first positive contactor are conducted. Compared with the general charging circuit, the connection point of the first positive contactor 305 of the embodiment of the present invention and the main circuit is arranged at the front end of the main positive contactor 301, so that the conduction of the first branch is not affected by the disconnection and closing of the main positive contactor 301, and thus the control method is more flexible.

[0062] The second branch of the embodiment of the present invention does not include a pre-charge contactor, but realizes the pre-charge of the second charging port by controlling the disconnection or closing of the main positive contactor 301 of the main circuit, thereby reducing one pre-charge contactor, reducing the volume of the parts, reducing the part cost, optimizing the spatial structure of the parts, and making the electric vehicle more advantageous in spatial layout.

[0063] Exemplarily, a DC shunt is also connected between the second negative contactor 309 and the main circuit. The DC shunt has a microcontroller (MCU) and is capable of Controller Area Network (CAN) communication.

[0064] In Figure 3 the example, both the first branch and the second branch are connected in series with the first negative contactor 302. The connection points of the first negative contactor 306 to the main circuit and the second negative contactor 309 to the main circuit are both set at the rear end of the main negative contactor 302, that is, the end far from the battery pack. In another embodiment of the present invention, as Figure 4 shown, the first branch is connected in parallel with the main negative contactor 302, the second branch is connected in series with the main negative contactor 302, and the connection point of the first negative contactor 306 to the main circuit can be set at the front end of the main negative contactor 302, that is, the second end of the first negative contactor 306 is connected to the first end of the main negative contactor 302, so that the conduction of the first branch is not affected by the opening or closing of the main negative contactor 302. In addition, the connection manners of other devices are substantially the same as those in Figure 3 and will not be elaborated herein.

[0065] Refer to Figure 5 and Figure 6 , in which based on Figure 3 and Figure 4 the shown charging circuit, the control flow of the charging circuit of the embodiment of the present invention is shown.

[0066] First, referring to Figure 5 , when a charging gun is inserted into the first charging port, it is determined whether the electric vehicle has entered the high-voltage power-on state. If it has not entered the high-voltage power-on state, the main negative contactor 302 and the contactor 303 are closed to perform the pre-charging operation of the main circuit and the first branch. After the pre-charging is completed, the main positive contactor 301 is closed and the contactor 303 is disconnected. After the DC converter is connected to the high-voltage circuit, it is started and provides a 12V auxiliary power supply to the electric vehicle; if the electric vehicle has entered the high-voltage power-on state, it indicates that the pre-charging has been performed, so there is no need to perform the operations of closing the main positive contactor 301, the main negative contactor 302, and the pre-charging of the main circuit.

[0067] Subsequently, it is determined whether the voltage of the first charging port is less than a preset threshold (taking 60V as an example). If the voltage is greater than 60V, it indicates that abnormal conduction may occur in the main circuit and the first branch. Therefore, the charging process of the first charging port is terminated. Otherwise, the charging process of the first charging port is entered, and the first negative contactor 306 and the first pre-charge contactor 307 are closed to perform the pre-charge operation of the main circuit and the first branch, that is, the battery pack pre-charges the first charging port. After the pre-charge is completed, the first positive contactor 305 is closed, and the first pre-charge contactor 307 is disconnected, and then charging of the battery pack is started through the first charging port. After the charging of the first charging port is completed, the first negative contactor 306 and the first positive contactor 305 are disconnected. If there is no other high-voltage process, the main positive contactor 301 and the main negative contactor 302 are disconnected, and the charging process of the first charging port ends. Otherwise, the charging process of the first charging port is directly terminated.

[0068] Refer to Figure 6 , when the charging gun is inserted into the second charging port, it is determined whether the electric vehicle has entered the high-voltage power-on state. If it has not entered the high-voltage power-on state, the main negative contactor 302 is closed to conduct the main circuit. Otherwise, the main positive contactor 301 needs to be disconnected to power down the vehicle's high voltage. Subsequently, it is determined whether the voltage of the second charging port is less than a preset threshold (taking 60V as an example). If the voltage is greater than 60V, it indicates that abnormal conduction may occur in the main circuit and the second branch. At this time, the charging process of the second charging port is terminated. Otherwise, the charging process of the second charging port is entered.

[0069] After entering the charging process, the second negative contactor 309 and the second positive contactor 308 are closed, and the contactor 303 is closed to perform the pre-charge operation of the main circuit and the second branch. After the pre-charge is completed, the main positive contactor 301 is closed, and the contactor 303 is disconnected. After the DC converter is connected to the high-voltage circuit, it is started and provides a 12V auxiliary power supply to the vehicle, and the second charging port starts to charge. After the charging is completed, the second positive contactor 308 and the second negative contactor 309 are disconnected. If there is no other high-voltage process, the main positive contactor 301 and the main negative contactor 302 are disconnected, and the charging process of the second charging port ends. Otherwise, the charging process of the second charging port is directly terminated.

[0070] Exemplarily, when the charging gun is first inserted into the second charging port and then into the first charging port, the charging process of the second charging port is first started, and then the process of the first charging port is started. The specific logic is as follows:

[0071] When a charging gun is inserted into the second charging port, it is judged whether the electric vehicle has entered the high-voltage power-on state. If it has not entered the high-voltage power-on state, the main negative contactor 302 is closed; otherwise, the main positive contactor 301 needs to be disconnected to power down the vehicle's high voltage. Subsequently, it is judged whether the voltage of the second charging port is less than 60V. If it is greater than 60V, the charging process ends; otherwise, the charging process is entered, and the second positive contactor 308, the second negative contactor 309, and the contactor 303 are closed to perform the pre-charging operation of the main circuit and the second branch. After the pre-charging is completed, the main positive contactor 301 is closed, and the contactor 303 is disconnected to start charging.

[0072] At this time, if a charging gun is inserted into the first charging port, it is judged whether the voltage of the first charging port is less than 60V. If it is greater than 60V, the charging process of the first charging port ends; otherwise, the charging process of the first charging port is entered, and the first negative contactor 306 and the first pre-charging contactor 307 are closed to perform the pre-charging operation of the first charging port. After the pre-charging is completed, the first positive contactor 305 is closed, and the first pre-charging contactor 307 is disconnected to start the charging process of the first charging port. After charging is completed, the second negative contactor 309, the second positive contactor 308, the first negative contactor 306, and the first positive contactor 305 are disconnected. If there is no other high-voltage process, the main positive contactor 301 and the main negative contactor 302 are disconnected, and the dual-gun charging process ends; otherwise, the dual-gun charging process is directly ended.

[0073] When the charging gun is inserted into the first charging port first and then into the second charging port, the charging process of the first charging port is started first, and then the process of the second charging port is started. The specific logic is as follows:

[0074] When a charging gun is inserted into the first charging port, it is judged whether the electric vehicle has entered the high-voltage power-on state. If it has not entered the high-voltage power-on state, the main negative contactor 302 and the contactor 303 are closed to perform the pre-charging operation of the main circuit. After the pre-charging is completed, the main positive contactor 301 is closed, and the contactor 303 is disconnected. After the DC is connected to the high-voltage circuit, it starts and provides a 12V auxiliary power supply to the electric vehicle; if it has already entered the high-voltage power-on state, there is no need to perform the closing of the main positive contactor 301, the negative contactor, and the pre-charging operation of the main circuit.

[0075] Subsequently, it is judged whether the voltage of the first charging port is less than 60V. If it is greater than 60V, the charging process of the first charging port ends; otherwise, the charging process of the first charging port is entered, and the first negative contactor 306 and the first pre-charging contactor 307 are closed to perform the pre-charging operation of the first charging port. After the pre-charging is completed, the first positive contactor 305 is closed, and the first pre-charging contactor 307 is disconnected to start charging.

[0076] At this time, if a charging gun is inserted into the second charging port, the main positive contactor 301 is first disconnected to cut off the high voltage of the whole vehicle. Then, it is judged whether the voltage of the second charging port is less than 60V. If it is greater than 60V, the charging process of the second charging port ends. Otherwise, the charging process of the second charging port is entered, the second negative contactor 309 and the second positive contactor 308 are closed, the contactor 303 is closed, and the pre-charging operation of the main circuit and the second branch is carried out. After the pre-charging is completed, the main positive contactor 301 is closed, and the contactor 303 is disconnected. After the DC is connected to the high-voltage circuit, it is started and a 12V auxiliary power supply is provided to the electric vehicle, and charging starts through the second charging port. After charging is completed, the second negative contactor 309, the second positive contactor 308, the first negative contactor 306, and the first positive contactor 305 are disconnected. If there is no other high-voltage process, the main positive contactor 301 and the main negative contactor 302 are disconnected, and the dual-gun charging process ends. Otherwise, the dual-gun charging process is directly ended.

[0077] In summary, the charging circuit of the embodiment of the present invention realizes the pre-charging of the second charging port by controlling the contactor 303, thereby reducing one pre-charging contactor and one pre-charging circuit, reducing the volume of parts, reducing the cost of parts, and optimizing the spatial structure of parts, making the electric vehicle more advantageous in spatial layout.

[0078] Another aspect of the embodiment of the present invention provides a charging control method, which is used for the charging circuit as described above, as Figure 7 shown, the charging control method 800 of the embodiment of the present invention includes the following steps:

[0079] In step S710, when pre-charging is carried out based on the second charging port, control the second positive contactor 308 to close and the main positive contactor 301 to disconnect, so that the positive pole of the second charging port is conducted with the positive pole of the battery pack through the pre-charging resistor 304;

[0080] In step S720, after the pre-charging based on the second charging port is completed, control the main positive contactor 301 to close, so that the positive pole of the second charging port is conducted with the positive pole of the battery pack. Further, after controlling the contactor 303 to disconnect, the main positive contactor 301 can be controlled to close, and the second positive contactor 308 and the second negative contactor 309 on the second branch can be controlled to close, and the second charging port charges the battery pack.

[0081] In other embodiments, the charging control method may further include:

[0082] When pre-charging based on the first charging port, control the first pre-charge contactor 307 to close and the first positive contactor 305 to open, so that the positive pole of the first charging port is conducted with the positive pole of the battery pack through the pre-charge resistor 304; subsequently, when the negative pole of the battery pack and the negative pole of the first charging port are conducted, pre-charging can be performed between the first charging port and the battery pack;

[0083] After completing the pre-charging based on the first charging port, control the first pre-charge contactor 307 to open and the first positive contactor 305 to close, so that the positive pole of the first charging port is conducted with the positive pole of the battery pack. Subsequently, when the negative pole of the battery pack and the negative pole of the first charging port are conducted, the first charging port can charge the battery pack.

[0084] In other embodiments, when charging based on the first charging port, first control the contactor 303 to close for pre-charging; after completing the pre-charging based on the first charging port, control the contactor 303 to open, control the main positive contactor 301 on the main circuit to close, and control the first pre-charge contactor 307 and the first negative contactor 306 to close for pre-charging; after completing the pre-charging of the first charging port, control the first pre-charge contactor 307 to open, control the first positive contactor 305 on the first branch to close, and the first charging port charges the battery pack.

[0085] The charging control method of the embodiments of the present invention has been described in detail above and will not be elaborated here. In this charging control method, by controlling the contactor 303 to pre-charge the main circuit and the second branch simultaneously, the control process is simplified.

[0086] Another aspect of the embodiments of the present invention provides an electric vehicle, which includes the charging circuit as described above. Since the electric vehicle of the embodiments of the present invention uses the charging circuit as described above, it also has the advantages of low component cost, small component volume, and compact space layout.

[0087] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present application thereto. Those of ordinary skill in the art can make various changes and modifications therein without departing from the scope and spirit of the present application. All such changes and modifications are intended to be included within the scope of the present application as claimed in the appended claims.

[0088] Those of ordinary skill in the art will realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of this application.

[0089] In several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed.

[0090] In the specification provided here, a large number of specific details are described. However, it can be understood that the embodiments of this application can be practiced without these specific details. In some instances, well-known methods, structures, and technologies are not shown in detail so as not to obscure the understanding of this specification.

[0091] Similarly, it should be understood that, in order to streamline this application and help understand one or more of the various inventive aspects, in the description of the exemplary embodiments of this application, the various features of this application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of this application should not be construed as reflecting the intention that the claimed application requires more features than are expressly recited in each claim. Rather, as reflected by the corresponding claims, the inventive point lies in being able to solve the corresponding technical problems with fewer features than all the features of a single disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into the detailed description, where each claim itself serves as a separate embodiment of this application.

[0092] Those skilled in the art can understand that, except for features that are mutually exclusive, any combination can be used for all the features disclosed in this specification (including the accompanying claims, abstract, and drawings) and all the processes or units of any method or device so disclosed. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstract, and drawings) can be replaced by an alternative feature that provides the same, equivalent, or similar purpose.

[0093] In addition, those skilled in the art can understand that although some of the embodiments described herein include certain features included in other embodiments rather than other features, the combination of features of different embodiments means that it is within the scope of this application and forms different embodiments. For example, in the claims, any one of the claimed embodiments can be used in any combination.

[0094] Each component embodiment of the present application can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. Those skilled in the art should understand that a microprocessor or a digital signal processor (DSP) can be used in practice to implement some or all of the functions of some of the modules according to the embodiments of the present application. The present application can also be implemented as a device program (such as a computer program and a computer program product) for executing part or all of the methods described herein. Such a program for implementing the present application can be stored on a computer-readable medium, or can be in the form of one or more signals. Such signals can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0095] It should be noted that the above embodiments illustrate rather than limit the present application, and those skilled in the art can design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The present application can be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In a unit claim listing several devices, several of these devices can be embodied by the same item of hardware. The use of the words first, second, and third, etc. does not denote any order. These words can be interpreted as names.

[0096] As described above, it is only the specific implementation manner of the present application or the description of the specific implementation manner. The protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed in the present application should be covered by the protection scope of the present application. The protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A charging circuit, characterized in that: The charging circuit comprises: A main circuit connected to the battery pack, the main circuit comprising a pre-charging resistor (304) and a main positive electrode contactor (301) both connected to the positive electrode of the battery pack; a first branch, connecting the main circuit and the first charging port, the first branch comprising a first positive contactor (305) and a first pre-charging contactor (307) both connected to the positive electrode of the first charging port; wherein the first pre-charging contactor (307) is connected in series with the pre-charging resistor (304); the first positive contactor (305) is connected between the battery pack and the first charging port, and is connected in parallel with the pre-charging resistor (304) and the main positive contactor (301); The second branch connects the main circuit and the second charging port, the second branch includes a second positive contactor (308) connected to the positive pole of the second charging port, and the second positive contactor (308) is connected in series with the pre-charging resistor (304) and the main positive contactor (301).

2. The charging circuit according to claim 1, characterized in that: When the second positive contactor (308) is closed and the main positive contactor (301) is opened, the positive electrode of the second charging port can be connected to the positive electrode of the battery pack through the pre-charging resistor (304).

3. The charging circuit according to claim 1, characterized in that: When the first pre-charging contactor (307) is disconnected and the first positive contactor (305) is closed, the positive electrode of the first charging port can be connected to the positive electrode of the battery pack.

4. The charging circuit according to claim 1, characterized in that: When the first pre-charging contactor (307) is closed and the first positive contactor (305) is opened, the positive electrode of the first charging port can be connected to the positive electrode of the battery pack through the pre-charging resistor (304).

5. The charging circuit according to claim 1, characterized in that: The first branch further comprises: a contactor (303) connected between the first pre-charging contactor (307) and the main positive contactor (301), and the contactor (303) is connected in parallel with the pre-charging resistor (304).

6. The charging circuit according to claim 5, characterized in that: When the first pre-charging contactor (307) is closed and the first positive contactor (305) and the contactor (303) are both disconnected, the positive electrode of the first charging port can be connected to the positive electrode of the battery pack through the pre-charging resistor (304).

7. The charging circuit according to claim 5, characterized in that: The contactor (303) is also connected between the pre-charging resistor (304) and the second positive electrode contactor (308).

8. The charging circuit according to claim 7, characterized in that: When the second positive contactor (308) and the contactor (303) are both closed, and the main positive contactor (301) is disconnected, the positive electrode of the second charging port can be connected to the positive electrode of the battery pack through the pre-charging resistor (304).

9. The charging circuit according to any one of claims 1 to 8, characterized in that: The first branch further comprises a first negative electrode contactor (306), wherein the first negative electrode contactor (306) is connected between the negative electrode of the battery pack and the negative electrode of the first charging port; The second branch further comprises a second negative electrode contactor (309), wherein the second negative electrode contactor (309) is connected between the negative electrode of the battery pack and the negative electrode of the second charging port.

10. The charging circuit according to claim 9, characterized in that: The main circuit also includes a main negative electrode contactor (302) connected to the negative electrode of the battery pack; The main negative contactor (302) is connected between the negative electrode of the battery pack and the first negative contactor (306); and / or, The main negative contactor (302) is connected between the negative electrode of the battery pack and the second negative contactor (309).

11. A charging control method, characterized in that: The method is used for the charging circuit according to any one of claims 1 to 10, and the method comprises: When pre-charging is performed based on the second charging port, the second positive contactor (308) is controlled to be closed, and the main positive contactor (301) is disconnected, so that the positive electrode of the second charging port is connected to the positive electrode of the battery pack through the pre-charging resistor (304); After the pre-charging based on the second charging port is completed, the main positive contactor (301) is controlled to be closed, so that the positive electrode of the second charging port is connected to the positive electrode of the battery pack.

12. The charging control method according to claim 11, characterized in that: The method further comprises: When pre-charging is performed based on the first charging port, the first pre-charging contactor (307) is controlled to be closed, and the first positive contactor (305) is disconnected, so that the positive electrode of the first charging port is connected to the positive electrode of the battery pack through the pre-charging resistor (304); After the pre-charging based on the first charging port is completed, the first pre-charging contactor (307) is controlled to be disconnected and the first positive contactor (305) is closed, so that the positive electrode of the first charging port is connected to the positive electrode of the battery pack.

13. An electric vehicle, characterized in that: The electric vehicle comprises a charging circuit as claimed in any one of claims 1-10.

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