Electric vehicle charging system and method and vehicle

Abstract

The invention discloses an electric vehicle charging system and method and a vehicle, and belongs to the field of vehicle charging. The system comprises a European standard charging base, an electric vehicle communication conversion module, a battery management system, a vehicle control unit and a vehicle-mounted charger, the electric vehicle communication conversion module is connected with the European standard charging base through a first communication protocol bus, and meanwhile the electric vehicle communication conversion module is connected with the battery management system; the battery management system, the vehicle control unit and the vehicle-mounted charger are connected through a second communication protocol bus. The system is compatible with domestic and foreign development, adapts to domestic and foreign charging facilities, is simple in charging, shortens the development cycle of export electric vehicles, reduces the development range, and saves the development cost and the vehicle manufacturing cost.

Description

Technical Field

[0001] The present invention belongs to the field of vehicle charging, and in particular, relates to an electric vehicle charging system, method and vehicle. Background Art

[0002] With growing global environmental awareness and energy transitions, market demand for new energy sources continues to grow. In particular, the application of new energy sources is becoming increasingly widespread in areas such as electric vehicles, energy storage, and distributed energy. China's production and exports of new energy vehicles have seen explosive growth, particularly in the European market. Leveraging strong technological innovation and price competitiveness, Chinese new energy vehicle companies are gradually gaining a foothold in the global market. Due to differences in power grid systems and charging standards across countries and regions, exporting new energy vehicles requires compatibility with charging grids and standards. Electric vehicle charging systems are primarily designed to accommodate significant variations in low-voltage distribution grids worldwide. From a grid perspective, voltage and frequency vary significantly, but even greater differences arise from more detailed aspects such as the three-phase connection to households, total power capacity, and power quality. This broader context has led to both subsequent divergence in charging standards and the urgent need for convergence. Developing vehicle AC / DC charging systems based on conventional electrical systems is completely unacceptable. Excessive variations would result in different versions of vehicles in different regions globally, significantly increasing overall costs. The domestic conductive charging system is implemented in accordance with GB / T 18487, the AC slow charging interface is implemented in accordance with GB / T20234.2, and the European standard slow charging interface and charging station are implemented in accordance with IEC 62196-1 and IEC62196-2. The current technology for solving charging adaptation problems for domestic export vehicles mainly relies on the communication conversion module (EVCC), which can solve the long development cycle and charging compatibility problems to a certain extent. However, the existing EVCC-based charging solutions have the disadvantages of complex solutions, long development cycles, and high hardware costs.

[0003] To this end, the present invention provides an electric vehicle charging system, method and vehicle. Summary of the Invention

[0004] The present invention aims to overcome the shortcomings of the existing technology and proposes an electric vehicle charging system, method and vehicle to achieve the following purposes: compatibility with domestic and foreign development, adaptation to domestic and foreign charging facilities, simple charging, shortening the development cycle and reducing the development scope of export electric vehicles, saving development costs and vehicle manufacturing costs.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an electric vehicle charging system, during charging, a European standard charging pile is inserted into a European standard charging seat through a charging gun, and the system includes a European standard charging seat, an electric vehicle communication conversion module, a battery management system, a vehicle controller, and an on-board charger, wherein the electric vehicle communication conversion module is connected to the European standard charging seat through a first communication protocol bus, and at the same time, the electric vehicle communication conversion module is connected to the battery management system; the battery management system, the vehicle controller, and the on-board charger are connected through a second communication protocol bus.

[0006] Preferably, the first communication protocol bus is a PLC communication protocol bus.

[0007] Preferably, the second communication protocol bus is a CAN communication protocol bus.

[0008] This application proposes a method for charging an electric vehicle, the method comprising the following steps:

[0009] Step S1: insert the charging gun of the European standard charging pile into the European standard charging seat, and the European standard charging seat sends the PP signal and the CP signal to the electric vehicle communication conversion module through the first communication protocol bus;

[0010] Step S2: After receiving the PP signal and the CP signal, the electric vehicle communication conversion module sends a wake-up signal to the battery management system. After the battery management system wakes up, it continues to wake up the vehicle controller and the on-board charger.

[0011] Step S3: After the entire system wakes up, the electric vehicle communication conversion module converts the PP signal and the CP signal into a CC signal and a CP signal, and then sends the CC signal and the CP signal to the second communication protocol bus network through the battery management system;

[0012] Step S4: The vehicle controller determines whether charging is allowed based on the CC signal and the vehicle status; if so, a charging permission instruction is sent to the battery management system; if not, the process returns to step S1;

[0013] Step S5: After receiving the charging permission instruction, the battery management system sends an instruction to close the electronic lock and the instruction to close the S2 switch to the electric vehicle communication conversion module; after the electronic lock and the S2 switch are closed, the battery management system sends a charging request and a requested charging current value to the on-board charger;

[0014] Step S6: The onboard charger determines the actual charging current value based on the CC and CP signals and the charging current value requested by the battery management system, and starts charging after requesting the corresponding current input from the European standard charging pile through the electric vehicle communication conversion module.

[0015] Preferably, the wake-up signal is a 12V hard-line CRG signal.

[0016] Preferably, in step S4, the vehicle controller determines whether charging is allowed according to the CC signal and the vehicle status, including:

[0017] If the CC signal indicates that the charging gun is not connected or the current vehicle is not in a stationary state, the vehicle controller determines that charging is not allowed; if the CC signal indicates that the charging gun is connected and the current vehicle is in a stationary state, the vehicle controller determines that charging is allowed.

[0018] Preferably, in step S4, when the vehicle controller determines that charging is allowed and sends a charging permission instruction, the vehicle controller forces the vehicle to enter the P gear.

[0019] Preferably, the method also includes: when the vehicle controller detects that the vehicle meets the charging termination conditions, the vehicle controller sends a charging exit signal to the second communication protocol bus network. Correspondingly, after the battery management system monitors that the charging current value of the on-board charger is less than a preset threshold, the battery management system requests to open the electronic lock and the S2 switch.

[0020] Preferably, in step S6, the onboard charger determines the actual charging current value according to the CC and CP signals and the charging current value requested by the battery management system, including:

[0021] Analyze the CC and CP signals to obtain AC current signals A1, V1 and A2, V2. A1 and V1 represent the maximum current and voltage supported by the charging gun or cable, respectively. A2 and V2 represent the maximum current and voltage that a European standard charging station can output.

[0022] The AC current values A1 and A2 are converted into DC current values F1 and F2 respectively. The conversion formula is as follows: F = A*V*H / B;

[0023] Where A is A1 or A2, and correspondingly, V is V1 or V2; H represents the efficiency of the on-board charger; B represents the battery pack voltage; and F represents the converted DC current value.

[0024] The minimum value among F1, F2 and the requested charging current value of the battery management system is taken as the actual charging current value.

[0025] The present application proposes a vehicle, which includes the electric vehicle charging system.

[0026] The technical effects of the present invention are:

[0027] This invention aims to provide a simplified charging system to address the long development cycles and high costs associated with European-standard charging systems. The BMS and OBC can be developed entirely in accordance with domestic standards, using the same communication protocols as in China. The EVCC acts as a bridge between the foreign power system and the vehicle.

[0028] At the same time, the present invention also proposes a corresponding electric vehicle charging method, which is simple and reliable, achieves compatibility with domestic and foreign charging facilities, and ensures the safety of the charging process. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 A structural block diagram of an electric vehicle charging system provided by an embodiment of the present invention;

[0030] Figure 2 This is a flow chart of a method for charging an electric vehicle provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The following is a further detailed description of the specific implementation of the present invention through the description of the embodiments with reference to the accompanying drawings, with the aim of helping those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention and to facilitate its implementation. It should be noted that the terms "first" and "second" described in this application are only used to facilitate the description of the technical solution to distinguish components. The corresponding component configurations may be the same or different, and are not intended to limit this application. In order to make the technical solution of the present invention clearer, the present invention is explained through the following embodiments.

[0032] This embodiment provides an electric vehicle charging system. When charging, a European standard charging pile is inserted into a European standard charging seat through a charging gun. Figure 1 As shown, the system is located on one side of the vehicle and includes a European standard charging seat, an electric vehicle communication conversion module (EVCC, Electric Vehicle Communication Controller), a battery management system (BMS), a vehicle controller (VCU), and an on-board charger (OBC). The electric vehicle communication conversion module is connected to the European standard charging seat through a first communication protocol bus. At the same time, the electric vehicle communication conversion module is connected to the battery management system; the battery management system, the vehicle controller, and the on-board charger are connected through a second communication protocol bus. The electric vehicle communication conversion module and the battery management system can be connected using a second communication protocol bus. The overall system structure is simple, using only two communication protocol buses, which greatly reduces the cost of the wiring harness.

[0033] As mentioned earlier, the electric vehicle communication conversion module is a core component of the national standard new energy vehicle export charging solution, used to convert different domestic and international communication protocols. An onboard charger is a charger fixed to the electric vehicle, capable of safely and automatically charging the electric vehicle's power battery. Based on data provided by the battery management system, the charger dynamically adjusts charging current and voltage parameters, executing corresponding actions to complete the charging process.

[0034] Based on this, the European standard charging pile and the vehicle achieve compatibility between different protocols through the electric vehicle communication conversion module. At this time, the BMS and OBC can be developed in full accordance with domestic standards and implement the same communication protocols as in China, thus ensuring the normal operation of the charging process. At the same time, this embodiment uses the first communication protocol bus and the second communication protocol bus to enable the intelligent devices inside the vehicle to transmit different signals, reducing the probability of information conflicts during the charging process.

[0035] In this embodiment, the first communication protocol bus is a PLC communication protocol bus, a commonly used international charging communication protocol. The second communication protocol bus is a CAN communication protocol bus, a commonly used domestic charging communication protocol. In this case, the electric vehicle communication conversion module, battery management system, vehicle controller, and onboard charger are all different nodes in the CAN network and can all access data from the CAN network. The electric vehicle communication conversion module serves as a transition link between the two communication protocol buses, enabling interaction between international power systems and domestic export vehicles.

[0036] According to the above electric vehicle charging system, this embodiment also proposes an electric vehicle charging method. Figure 2 The method is explained in detail.

[0037] Step S1: Insert the charging gun of a European-standard charging pile into a European-standard charging station. The European-standard charging station sends a PP signal and a CP signal to the electric vehicle communication conversion module via a first communication protocol bus (hereinafter referred to as the PLC bus). The PP signal indicates whether the charging gun is connected to the vehicle, and the CP signal indicates the charging method and charging pile load capacity.

[0038] Step S2: After receiving the PP signal and the CP signal, the electric vehicle communication conversion module sends a wake-up signal to the battery management system. After the battery management system wakes up, it continues to wake up the vehicle controller and the on-board charger.

[0039] Among them, after any one of the battery management system, vehicle controller, and on-board charger receives the wake-up signal and wakes up, it can send a wake-up signal to the second communication protocol bus network (hereinafter referred to as the CAN network) to avoid thereby ensuring that all components of the entire system wake up in time.

[0040] In this embodiment, the wake-up signal is a 12V hard-wired CRG (clock reset) signal, used to wake up other components at a high level. This hard-wired wake-up method transmits signals directly through a physical connection, which is unaffected by electromagnetic interference and network failures. This makes signal transmission more stable and reliable, while also reducing latency and speeding up wake-up.

[0041] Step S3: After the entire system wakes up, the electric vehicle communication conversion module converts the PP and CP signals into CC and CP signals and sends them to the CAN network. The CC signal not only contains information about whether the charging gun is connected to the vehicle, but also includes the load capacity of the charging gun or cable.

[0042] Step S4: The vehicle controller determines whether charging is allowed based on the CC signal and the vehicle status; if allowed, a charging permission instruction is sent to the battery management system; if not allowed, the process returns to step S1.

[0043] The vehicle controller determines whether charging is allowed according to the CC signal and the vehicle status, including:

[0044] If the CC signal indicates the charging gun is not connected or the vehicle is not currently stationary, the vehicle controller determines that charging is not allowed. If the charging gun is not properly connected, the vehicle cannot start charging. If the vehicle is in motion, connecting the charging gun will cause dragging, endangering charging safety. Therefore, the vehicle controller only determines that charging is allowed when the CC signal indicates the charging gun is connected and the vehicle is currently stationary.

[0045] In addition, when the vehicle controller determines that charging is allowed and sends a charging permission instruction, no matter what gear the vehicle is currently in, the vehicle controller forces the vehicle to enter P gear, prohibits the vehicle from driving or coasting, and avoids dragging the charging gun to ensure charging safety.

[0046] Step S5: After receiving the charging permission instruction, the battery management system sends an electronic lock closing instruction and an S2 switch closing instruction to the electric vehicle communication conversion module; after the electronic lock and the S2 switch are closed, the battery management system sends a charging request and a requested charging current value to the on-board charger.

[0047] The S2 switch is the EVCC's built-in S2 switch and is used to control the vehicle's charging status. Charging begins only when the S2 switch is closed, and cannot occur when the S2 switch is open. The electronic lock is used to lock the charging gun in place after it is inserted into the socket to prevent it from being accidentally removed. In this embodiment, it is controlled by the electric vehicle communication conversion module.

[0048] The status of the electronic lock and S2 switch is fed back to the battery management system in real time. Only when the electronic lock and S2 switch are both closed, it means that the vehicle is ready for charging. At this time, the battery management system sends a charging request and the requested charging current value to the on-board charger.

[0049] Step S6: The onboard charger determines the actual charging current value based on the CC and CP signals and the charging current value requested by the battery management system, and starts charging after requesting the corresponding current input from the European standard charging pile through the electric vehicle communication conversion module.

[0050] The onboard charger determines the actual charging current value based on the CC and CP signals and the charging current value requested by the battery management system. The values include:

[0051] Analyze the CC and CP signals to obtain AC current signals A1, V1 and A2, V2. A1 and V1 represent the maximum current and voltage supported by the charging gun or cable, respectively. A2 and V2 represent the maximum current and voltage that a European standard charging station can output.

[0052] The AC current values A1 and A2 are converted into DC current values F1 and F2 respectively. The conversion formula is as follows:

[0053] F = A*V*H / B;

[0054] Where A is A1 or A2, and correspondingly, V is V1 or V2; H represents the efficiency of the on-board charger; B represents the battery pack voltage; and F represents the converted DC current value.

[0055] The minimum of F1, F2, and the battery management system's requested charging current is taken as the actual charging current, allowing charging to begin while ensuring the safety of the charging system. During the charging process, the battery management system monitors the charging status and charging current and voltage in real time and transmits them to the CAN network.

[0056] Finally, the method of this embodiment also includes: when the vehicle controller detects that the vehicle meets the charging end conditions, the vehicle controller sends a charging exit signal to the CAN network. Correspondingly, after receiving the charging exit signal, the battery management system monitors whether the charging current value of the on-board charger is less than a preset threshold (set to 1A in this embodiment, which can be flexibly selected according to actual conditions during implementation). If so, the battery management system requests to open the electronic lock and S2 switch to prevent the impact of directly exiting charging under high current on the charging circuit, thereby achieving safe exit from charging. Finally, after exiting charging, the vehicle controller controls the vehicle system to enter sleep mode and wait for the next charge.

[0057] The vehicle meets the charging end conditions including:

[0058] The power battery reaches a preset power threshold (e.g. 95%);

[0059] The charging time reaches the preset time, which is customized by the user according to needs;

[0060] The vehicle controller receives a command to end charging, which can come from the vehicle computer, key, etc.

[0061] The vehicle controller receives a fault signal;

[0062] If any of the above conditions is met, charging is terminated.

[0063] This embodiment realizes the charging adaptation between the European standard charging pile and the whole vehicle charging, and does not require too many changes to the charging system that has been fully developed in China. The current EVCC and BMS development are mature solutions. Deploying them based on the system of this embodiment saves development cycle and cost. At the same time, the charging method based on this is simple and not prone to problems. For OBC development, compared with domestic development, it is only necessary to cancel CC and CP detection, set the internal S2 switch to normally closed, and wake up through the vehicle network. The modification is convenient and easy to implement. At the same time, compared with the commonly used OBC, the wiring harness is simpler, which reduces the cost. In short, this embodiment is compatible with domestic and foreign development needs. The differences between domestic and foreign development are small, and they can be developed in parallel, which saves development cycle and development cost to a certain extent and realizes the platform application of products.

[0064] This embodiment further provides a vehicle, which includes the above-mentioned electric vehicle charging system. The vehicle can be either a pure electric vehicle or a hybrid vehicle.

[0065] The present invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described method. Any non-substantial improvements made using the method concepts and technical solutions of the present invention, or any direct application of the above-described concepts and technical solutions to other situations without modification, fall within the scope of protection of the present invention.

Claims

1. An electric vehicle charging system, wherein a European standard charging pile is inserted into a European standard charging station via a charging gun, and is characterized by: The system includes a European standard charging seat, an electric vehicle communication conversion module, a battery management system, a vehicle controller, and an on-board charger, wherein the electric vehicle communication conversion module is connected to the European standard charging seat through a first communication protocol bus, and at the same time, the electric vehicle communication conversion module is connected to the battery management system; the battery management system, the vehicle controller, and the on-board charger are connected through a second communication protocol bus.

2. The electric vehicle charging system according to claim 1, characterized in that: The first communication protocol bus is a PLC communication protocol bus.

3. An electric vehicle charging system according to claim 1 or 2, characterized in that: The second communication protocol bus is a CAN communication protocol bus.

4. An electric vehicle charging method according to the electric vehicle charging system according to any one of claims 1-2, characterized in that: The method comprises the following steps: Step S1: insert the charging gun of the European standard charging pile into the European standard charging seat, and the European standard charging seat sends the PP signal and the CP signal to the electric vehicle communication conversion module through the first communication protocol bus; Step S2: After receiving the PP signal and the CP signal, the electric vehicle communication conversion module sends a wake-up signal to the battery management system. After the battery management system wakes up, it continues to wake up the vehicle controller and the on-board charger. Step S3: After the entire system wakes up, the electric vehicle communication conversion module converts the PP signal and the CP signal into a CC signal and a CP signal, and then sends the CC signal and the CP signal to the second communication protocol bus network through the battery management system; Step S4: The vehicle controller determines whether charging is allowed based on the CC signal and the vehicle status; if so, a charging permission instruction is sent to the battery management system; if not, the process returns to step S1; Step S5: After receiving the charging permission instruction, the battery management system sends an instruction to close the electronic lock and the instruction to close the S2 switch to the electric vehicle communication conversion module; after the electronic lock and the S2 switch are closed, the battery management system sends a charging request and a requested charging current value to the on-board charger; Step S6: The onboard charger determines the actual charging current value based on the CC and CP signals and the charging current value requested by the battery management system, and starts charging after requesting the corresponding current input from the European standard charging pile through the electric vehicle communication conversion module.

5. The electric vehicle charging method according to claim 4, characterized in that: The wake-up signal is a 12V hard-wired CRG signal.

6. The electric vehicle charging method according to claim 4, characterized in that: In step S4, the vehicle controller determines whether charging is allowed according to the CC signal and the vehicle status, including: If the CC signal indicates that the charging gun is not connected or the current vehicle is not in a stationary state, the vehicle controller determines that charging is not allowed; if the CC signal indicates that the charging gun is connected and the current vehicle is in a stationary state, the vehicle controller determines that charging is allowed.

7. An electric vehicle charging method according to claim 4 or 6, characterized in that: In step S4, when the vehicle controller determines that charging is allowed and sends a charging permission instruction, the vehicle controller forces the vehicle to enter the P gear.

8. The electric vehicle charging method according to claim 4, characterized in that: The method also includes: when the vehicle controller detects that the vehicle meets the charging termination conditions, the vehicle controller sends a charging exit signal to the second communication protocol bus network; correspondingly, after the battery management system monitors that the charging current value of the on-board charger is less than a preset threshold, the battery management system requests to open the electronic lock and the S2 switch.

9. The electric vehicle charging method according to claim 4, characterized in that: In step S6, the onboard charger determines the actual charging current value based on the CC and CP signals and the charging current value requested by the battery management system, including: Analyze the CC and CP signals to obtain AC current signals A1, V1 and A2, V2. A1 and V1 represent the maximum current and voltage supported by the charging gun or cable, respectively. A2 and V2 represent the maximum current and voltage that a European standard charging station can output. The AC current values A1 and A2 are converted into DC current values F1 and F2 respectively. The conversion formula is as follows: F = A*V*H / B; Where A is A1 or A2, and correspondingly, V is V1 or V2; H represents the efficiency of the on-board charger; B represents the battery pack voltage; and F represents the converted DC current value. The minimum value among F1, F2 and the requested charging current value of the battery management system is taken as the actual charging current value.

10. A vehicle according to the electric vehicle charging system according to any one of claims 1-2, characterized in that: The vehicle includes the electric vehicle charging system.

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