Charging pile diagnosis method for direct current charging, charging control method, system and program product

Abstract

The invention provides a charging pile diagnosis method for direct current charging, and the method is executed at a vehicle end, and comprises the steps: determining a terminal voltage of a vehicle end fast charging circuit as a reference voltage when a charging gun is inserted into a charging interface of a vehicle; when a handshake message sent by the charging pile is received, closing a first side relay of the vehicle end fast charging circuit, and determining a terminal voltage of the vehicle end fast charging circuit when the first side relay is closed as a first voltage; comparing a difference value between the first voltage and the reference voltage with a voltage threshold value, and if the difference value is greater than the voltage threshold value, continuing the charging process; wherein the terminal voltage of the vehicle end fast charging circuit is the voltage of the end, close to the charging pile side, of the vehicle end fast charging circuit. The invention further provides a controller, a vehicle-mounted charging system and the like.

Description

Technical Field

[0001] The present application relates to vehicle technology, and more specifically, to charging pile diagnostic technology for direct current charging. Background Art

[0002] According to the existing technology, during the fast charging process of new energy vehicles, the charging pile and the vehicle form a charging loop. According to the national standard, the pre-charging circuit of the loop exists on the charging pile side. Therefore, during charging, if the timing of the pile-end relay is abnormal, it will close before the vehicle end; it may also happen that after the insulation test of the pile end, the relays on both sides of the pile end are stuck and cannot be disconnected, resulting in vehicles that do not have a reserved fast charging pre-charging circuit. When the fast charging relay on the vehicle end is closed, surge current is generated between the pile end and the vehicle end, causing the fast charging relay on the vehicle end to stick. It is necessary to propose a solution to this. Summary of the invention

[0003] According to some embodiments of the present application, a charging pile diagnostic method for DC charging is provided, which is executed on the vehicle side, and the method includes determining the terminal voltage of the vehicle-side fast charging circuit as a reference voltage when the charging gun is inserted into the charging interface of the vehicle; when receiving a handshake message sent by the charging pile, closing the first side relay of the vehicle-side fast charging circuit, and determining the terminal voltage of the vehicle-side fast charging circuit when the first side relay is closed as a first voltage; comparing the difference between the first voltage and the reference voltage with a voltage threshold, and if the difference is greater than the voltage threshold, continuing the charging process; wherein the terminal voltage of the vehicle-side fast charging circuit is the voltage at the end of the vehicle-side fast charging circuit close to the charging pile side.

[0004] As an example, the method may also include: comparing the difference between the first voltage and the reference voltage with a voltage threshold, if the difference is less than the voltage threshold, disconnecting the first side relay and closing the second side relay, and determining the terminal voltage of the vehicle-end fast charging circuit when the second side relay is closed as the second voltage; comparing the difference between the second voltage and the reference voltage with a voltage threshold, if the difference is greater than the voltage threshold, continuing the charging process; if the difference is less than the voltage threshold, it indicates that the charging pile is abnormal and charging is terminated.

[0005] As an example, in the method, the first side relay and the second side relay are respectively a positive relay and a negative relay; or, the first side relay and the second side relay are respectively a negative relay and a positive relay.

[0006] Any of the above methods can be executed by the vehicle's charging control system.

[0007] According to an example of the present application, a charging control method is also provided, which includes any one of the charging pile diagnosis methods for DC charging according to the examples of the present application.

[0008] According to an example of the present application, a controller is further provided, which includes a memory and a processor. The memory stores program instructions, and the processor executes the program instructions and implements any method described in the present application during the execution process.

[0009] According to an example of the present application, an on-vehicle charging system is also provided. The charging system is configured to perform any one of the methods described herein, or may include the controller provided by the present application.

[0010] According to an example of the present application, a vehicle is also provided. The vehicle includes the controller provided by the present application, or is configured to execute any one of the methods described herein.

[0011] According to an example of the present application, a program product is also provided. The program product includes program instructions. When the program instructions are executed by a processor, any one of the methods described herein is implemented.

[0012] According to an example of the present application, a storage medium is also provided, on which program instructions are stored, and when the program instructions are executed by a processor, any one of the methods described herein is implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The following will describe the embodiments of the present application in detail with reference to the accompanying drawings so that the present application can be more fully understood, wherein:

[0014] Figure 1 The fast charging connection circuit between the charging pile and the vehicle is shown;

[0015] Figure 2 It is a flow chart of a charging pile diagnosis method for DC charging according to an embodiment of the present application. DETAILED DESCRIPTION

[0016] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the following will be combined with the accompanying drawings to clearly and completely describe the implementation methods of the present application. It should be noted that the described implementation methods are only part of the implementation methods of the technical solution of the present application, not all. All other implementation methods obtained by ordinary technicians in this field based on the implementation methods recorded in the application documents without paying creative work are covered by the protection scope of the present application.

[0017] Figure 1 The diagram shows the fast charging connection circuit between the charging pile and the vehicle. In the following text, the charging pile is referred to as the pile end and the vehicle is referred to as the vehicle end. Figure 1 As shown, after the charging pile of the charging station is connected to the vehicle charging port, the positive relay 20 and the negative relay 22 at the vehicle end are respectively connected to the corresponding relay 10 and the negative relay 12 at the pile end, thereby forming a charging circuit.

[0018] Figure 2 The present invention is a flow chart of a charging pile diagnosis method for DC charging according to an embodiment of the present application. The method is executed by a vehicle to diagnose the charging pile, thereby determining whether to continue the charging procedure. Specifically, it can be executed by the vehicle's charging management system, or by the vehicle's battery management system or other systems or components of the vehicle, as long as the process of the method can be implemented to diagnose the charging pile.

[0019] For the fast charging circuit, generally speaking, there is already a voltage detection module in the vehicle. Therefore, in the example of the present application, the voltage on the charging pile side of the vehicle-side fast charging circuit can be determined by reading the voltage from the existing voltage detection module. Alternatively, if there is no such detection module in the vehicle, a voltage detection circuit or a voltage sensor can be provided to obtain the voltage.

[0020] In step S202, when it is detected that the charging gun is inserted into the vehicle charging interface, the terminal voltage of the vehicle-side fast charging circuit is determined and used as the reference voltage. That is, the voltage at the end of the vehicle-side fast charging circuit close to the charging pile is determined as the reference voltage. Specifically, before the charging gun and the charging interface are electrically contacted but the charging handshake is not completed, the voltage at the end of the fast charging circuit close to the charging pile is read. The end of the vehicle-side fast charging circuit close to the charging pile refers to the end where the fast charging circuit is electrically connected to the charging pile (more specifically, to the charging gun). In this connection Figure 1 Simple explanation, Figure 1 In the example, the vehicle-side fast charging circuit is connected to the first end AB of the charging pile, that is, the input end of the vehicle-side fast charging circuit is the end of the vehicle-side fast charging circuit close to the charging pile. Therefore, in this example, when the charging gun is inserted into the charging port of the vehicle, the voltage Vab at the AB end is obtained as the reference voltage.

[0021] In step S204, when the vehicle end receives a handshake message such as a CML message sent by the charging pile end, the first side relay of the vehicle end fast charging circuit is closed, and the first voltage on the charging pile side of the vehicle end fast charging circuit is determined when the first side relay is closed.

[0022] In step S206, the difference between the first voltage and the reference voltage is calculated, and the difference is compared with the voltage threshold. The voltage threshold is configured in advance. If the difference is greater than the voltage threshold, it indicates that the charging pile is normal. According to this example, step S300 will be entered to continue the charging process.

[0023] When the difference between the first voltage and the reference voltage is less than the voltage threshold, further diagnosis can be performed according to the example of the present application. For example, in step S208, the first side relay is disconnected and the second side relay is closed, and the second voltage on the charging pile side of the vehicle-end fast charging circuit is determined when the first side relay is disconnected and the second side relay is closed. In step S210, the difference between the second voltage and the reference voltage is determined. If the difference between the second voltage and the reference voltage is greater than the voltage threshold, it indicates that the charging pile is normal, and the process proceeds to step S300 to continue the charging process. If the difference between the second voltage and the reference voltage is less than the voltage threshold, it indicates that the charging pile is abnormal. According to the example of the present application, in the case of an abnormal charging pile, charging is terminated.

[0024] In combination Figure 2 In the example described, the first side relay may be a positive relay of the vehicle fast charging circuit, and correspondingly, the second side relay is a negative relay of the vehicle fast charging circuit. Alternatively, when the first side relay is a negative relay of the vehicle fast charging circuit, the second side relay is a positive relay of the vehicle fast charging circuit.

[0025] Also refer to Figure 1 and Figure 2 When the charging gun at the charging pile end is inserted into the charging port of the vehicle, the voltage Vab at the AB end of the vehicle-side fast charging circuit close to the charging pile side is obtained (S202). _ 0, as the reference voltage. Subsequently, the vehicle end receives the CML message sent by the charging pile end, closes the single-side relay, for example, closes the positive relay 20, and then obtains (S204) the voltage Vab_1 at the AB end of the vehicle end fast charging circuit close to the charging pile side as the first voltage. Calculate the first voltage Vab _ 1 and the reference voltage Vab_0, and compare it with the voltage threshold (S206). If it is greater than the voltage threshold, it means that the charging pile is normal and the charging process continues. If it is less than the voltage threshold, the positive relay 20 is disconnected, the negative relay 10 is closed, and the voltage Vab at the AB end of the vehicle-side fast charging circuit close to the charging pile side is determined (S208). _ 2, as the second voltage. Calculate the second voltage Vab _ 2 and the reference voltage Vab_0, and compares it with the voltage threshold (S210). If the second voltage Vab_2 is equal to the reference voltage Vab _ 0 is greater than the voltage threshold, indicating that the charging pile is normal and the charging process continues. _ 2 and reference voltage Vab _ 0 is less than the voltage threshold, terminating the charging process.

[0026] According to the national standard GB / T 27930.1, the pile end will send a CML message after completing the insulation test, and the pile end relay should be disconnected at this time. Figure 1and Figure 2 After the vehicle end receives the CML message, it closes the single-side relay of the vehicle-end fast charging circuit, reads the voltage difference close to the pile end at this time, and obtains the first voltage Vab_l. If the relays on both sides of the pile end are adhered, the single-side relay on the vehicle end is closed at this time. Due to the presence of the large capacitor on the pile end, the mutation of V1 will be suppressed. According to the simulation, the voltage value of V1 should be less than 10V at this time. If the relays on both sides of the pile end are disconnected normally, the single-side relay on the vehicle end is closed at this time, and V1 is approximately equal to half of the voltage of the high-voltage battery pack. Based on this, the voltage threshold M1 can be determined in advance, that is, the voltage threshold M1 for judging whether the pile-end relay is adhered or not is obtained according to the circuit simulation. In order to avoid voltage measurement errors, the voltage difference Vab of the positive and negative relays is read after the gun is plugged in (that is, the charging gun is connected to the charging port on the vehicle end) but before the pile end sends the handshake message CML, and the relays on the charging pile and the vehicle end are disconnected. _ 0 is used as the compensation value, and it is judged whether Vab_1-Vab_0 is greater than the voltage threshold M1. If it is greater than M1, there is no abnormality at the pile end and charging can continue.

[0027] If there is adhesion of one-sided relay at the pile end, if the closed vehicle-end relay is on the same side, VaD_1 is easily affected by the resistance value of the insulation detection circuit at the pile end, showing a relatively low voltage level. Considering that there is no safety and performance risk in the adhesion of one-sided relay at the pile end, vehicle-end charging can still be performed. Therefore, in order to avoid the scenario of terminating charging due to adhesion of one-sided relay at the pile end, according to the example of this application, when the value of VaD_1-VaD_0 is less than the voltage threshold M1, the charging process is not directly terminated, but a second closure is performed. The second closure includes disconnecting the closed relay of the current vehicle-end fast charging circuit, closing the relay on the other side, and reading the voltage VaD_2. If the pile end is adhered on both sides at this time, the simulation V2 should be less than 10V because the large capacitance at the pile end also suppresses the mutation of V2. Similarly, it is judged whether the difference between VaD_2 and Vab_0 (Vab_1-Vab_0) is less than the voltage threshold M1. If it is less than M1, the relays on both sides of the pile end are adhered, the charging pile is abnormal, and the charging is terminated. On the contrary, it indicates that the relay on one side of the charging pile is stuck and the charging process can continue.

[0028] According to the method of the example of this application, there is no need to add additional hardware settings in the vehicle, and the vehicle-side detection of the charging pile can be limited by setting a diagnostic program on the vehicle side, thereby avoiding the charging pile relay from sticking or the charging pile relay closing sequence abnormality, and the surge current generated on the vehicle side. For example, even if a vehicle without a fast charging preset resistor does not increase the fast charging pre-charge resistor, the problem of fast charging relay sticking under load closure can be avoided by executing the method of the example of this application.

[0029] According to an example of the present application, a charging control method is also provided, which includes a charging pile diagnosis method for DC charging according to an example of the present application.

[0030] According to an example of the present application, a controller is also provided, which includes a memory and a processor. The memory stores program instructions, and the processor executes the program instructions and implements any one of the methods described in the embodiments of the present application during the execution process.

[0031] According to an example of the present application, an on-vehicle charging system is also provided. The charging system is configured to perform any one of the methods described herein, or may include the controller provided by the present application.

[0032] According to an example of the present application, a vehicle is also provided. The vehicle includes the controller provided by the present application, or is configured to execute any one of the methods described herein.

[0033] Although specific embodiments of the present application have been shown and described in detail to illustrate the principles of the present application, it should be understood that the present application may be implemented in other ways without departing from such principles, for example, the technical features of the various embodiments / examples / examples of the present application may be combined with each other to form new implementation methods.

Claims

1. A charging pile diagnosis method for DC charging, characterized in that: The method is executed on the vehicle side, and the method includes: When the charging gun is inserted into the charging port of the vehicle, the terminal voltage of the fast charging circuit at the vehicle end is determined as the reference voltage; When receiving the handshake message sent by the charging pile, closing the first side relay of the vehicle-end fast charging circuit, and determining the terminal voltage of the vehicle-end fast charging circuit when the first side relay is closed as the first voltage; comparing a difference between the first voltage and the reference voltage with a voltage threshold, and continuing the charging process if the difference is greater than the voltage threshold; Among them, the terminal voltage of the vehicle-end fast charging circuit is the voltage of the end of the vehicle-end fast charging circuit close to the charging pile side.

2. The method according to claim 1, characterized in that The method further comprises: Comparing the difference between the first voltage and the reference voltage with a voltage threshold, and if the difference is less than the voltage threshold, disconnecting the first-side relay and closing the second-side relay, and determining the terminal voltage of the vehicle-end fast charging circuit when the second-side relay is closed as the second voltage; The difference between the second voltage and the reference voltage is compared with a voltage threshold. If the difference is greater than the voltage threshold, the charging process continues; if the difference is less than the voltage threshold, it indicates that the charging pile is abnormal and the charging is terminated.

3. The method according to any one of claims 1 to 2, characterized in that The first-side relay and the second-side relay are respectively a positive relay and a negative relay; or, the first-side relay and the second-side relay are respectively a negative relay and a positive relay.

4. The method according to any one of claims 1 to 3, characterized in that The method is executed by a charging control system of the vehicle.

5. A charging control method, characterized in that: The method comprises the charging pile diagnosis method according to any one of claims 1 to 4.

6. A program product, characterized in that The program product includes program instructions, and when the program instructions are executed by a processor, the charging pile diagnosis method according to any one of claims 1 to 4 is implemented.

7. A controller, characterized in that: The controller includes a memory and a processor, the memory stores instructions, and the processor implements the charging pile diagnosis method according to any one of claims 1 to 4 when executing the instructions.

8. A vehicle charging system, characterized in that: The on-vehicle charging system is configured to be able to execute the charging pile diagnostic method according to any one of claims 1 to 4; or includes a controller according to claim 6.

9. A vehicle, characterized in that: The vehicle is configured to execute the charging pile diagnostic method according to any one of claims 1 to 4; or includes a controller according to claim 6.

10. A storage medium storing program instructions, characterized in that: The charging pile diagnosis method according to any one of claims 1 to 4 is implemented during the execution of the program instructions by the processor.

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