Charging control method of electric vehicle, charging system and electric vehicle

Abstract

The invention discloses a charging control method of an electric automobile, a charging system and the electric automobile, and the method comprises the steps: when a single-gun direct current charging mode is switched to a double-gun direct current charging mode, according to the current maximum allowable charging current of a power battery and the direct current side output current of a vehicle-mounted charger, the single-gun direct current charging mode is switched to the double-gun direct current charging mode; determining the current maximum allowable charging current of the second direct current charging port; and determining the current maximum allowable charging current of the first direct current charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second direct current charging port and the direct current side output current of the vehicle-mounted charger. Current can be dynamically distributed, and the charging time is shortened.

Description

Technical Field

[0001] This application belongs to the field of electronic technology, and mainly relates to a method for charging control of an electric vehicle, a charging system and an electric vehicle. Background Art

[0002] Currently, in the dual-gun DC charging technology of electric vehicles, the current of the two DC charging ports for dual-gun DC charging is usually equally distributed, that is, the charging current of each of the two charging circuits accounts for half of the maximum charging current currently allowed by the power battery. This charging method takes a long charging time, resulting in low charging efficiency. Therefore, how to improve the efficiency of dual-gun DC charging has become an urgent problem to be solved. Summary of the Invention

[0003] This application provides a method for charging control of an electric vehicle, a charging system and an electric vehicle, which dynamically distributes current and shortens the charging time.

[0004] To achieve the above object, in a first aspect, this application provides a method for single-gun to dual-gun DC charging control of an electric vehicle, which is applied to a charging system of a dual-charging-port electric vehicle. The charging system includes a first DC charging port, a second DC charging port, a first switch module, a second switch module, a first buck-boost module, an on-vehicle charger, a control module and a power battery. The first DC charging port is connected to the input end of the buck-boost module through the first switch module, the output end of the buck-boost module is connected to the power battery, the second DC charging port is connected to the power battery through the second switch module, the first DC charging port and the second DC charging port are connected to the input end of the control module, and the first switch module and the second switch module are connected to the output end of the control module. The method includes:

[0005] When switching from the single-gun DC charging mode to the dual-gun DC charging mode, determine the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger;

[0006] Determine the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port and the output current on the DC side of the on-vehicle charger.

[0007] A possible implementation manner, the determining the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger includes:

[0008] When the current maximum allowable charging current of the power battery is less than or equal to the first threshold, the current maximum allowable charging current of the second DC charging port is the result of multiplying the first ratio by the difference between the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger.

[0009] A possible implementation method for determining the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger includes:

[0010] The current maximum allowable charging current of the first DC charging port is the difference obtained by subtracting the current charging current of the second charging port and the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

[0011] A possible implementation method for determining the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger includes:

[0012] When the current maximum allowable charging current of the power battery is greater than the first threshold, the current maximum allowable charging current of the second DC charging port is the difference obtained by subtracting the output current on the DC side of the on-vehicle charger and a first preset value from the current maximum allowable charging current of the power battery.

[0013] A possible implementation method for determining the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger includes:

[0014] The current maximum allowable charging current of the first DC charging port is the minimum value between the maximum allowable current of the buck-boost module and the result obtained by subtracting the current charging current of the second DC charging port and the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

[0015] A possible implementation method is that the first threshold is 60 A.

[0016] A possible implementation, the charging system includes a first DC charging port, a second DC charging port, a first switching module, a second switching module, a second buck-boost module, an on-vehicle charger, a control module, and a power battery. The first DC charging port is connected to the input end of the buck-boost module through the first switching module, and the output end of the buck-boost module is connected to the power battery. The second DC charging port is connected to the input end of the buck-boost module through the second switching module, and the output end of the buck-boost module is connected to the power battery. The first DC charging port and the second DC charging port are connected to the input end of the control module, and the first switching module and the second switching module are connected to the output end of the control module. The method includes:

[0017] When switching from the single-gun DC charging mode to the double-gun DC charging mode, determine the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger;

[0018] Determine the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger

[0019] A possible implementation, the determining the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger includes:

[0020] When the current maximum allowable charging current of the power battery is less than or equal to the second threshold, the current maximum allowable charging current of the second DC charging port is the result of multiplying the second ratio by the difference between the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger.

[0021] A possible implementation, the determining the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger includes:

[0022] The current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second DC charging port and then minus the output current on the DC side of the on-vehicle charger.

[0023] A possible implementation, the when switching from the single-gun DC charging mode to the double-gun DC charging mode, determine the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger includes:

[0024] When the current maximum allowable charging current of the power battery is greater than the second threshold, the current maximum allowable charging current of the second DC charging port is the minimum value among the maximum charging current of the second DC charging port, the current maximum allowable charging current of the power battery minus the output current of the DC side of the on-vehicle charger minus a second preset value.

[0025] A possible implementation manner, where determining the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current of the DC side of the on-vehicle charger includes:

[0026] The current maximum allowable charging current of the first DC charging port is the minimum value among the maximum charging current of the first DC charging port, the current maximum allowable charging current of the power battery minus the current charging current of the second DC charging port minus the output current of the DC side of the on-vehicle charger.

[0027] A possible implementation manner, where the second threshold is 120 A.

[0028] In a second aspect, the charging system of the electric vehicle of the present application includes a first DC charging port, a second DC charging port, a first switching module, a second switching module, a first buck-boost module, an on-vehicle charger, a control module, and a power battery, where:

[0029] The first DC charging port is connected to the input end of the buck-boost module through the first switching module, the output end of the buck-boost module is connected to the power battery, the second DC charging port is connected to the power battery, the first DC charging port is connected to the control module through the first switching module, and the second DC charging port is connected to the control module through the second switching module;

[0030] The control module is configured to determine the current maximum allowable charging current of the second DC charging port based on the current maximum allowable charging current of the power battery and the output current of the DC side of the on-vehicle charger when switching from the single-gun DC charging mode to the double-gun DC charging mode;

[0031] The control module is further configured to determine the current maximum allowable charging current of the first DC charging port based on the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current of the DC side of the on-vehicle charger.

[0032] A possible implementation manner, where the connection of the second DC charging port to the power battery includes:

[0033] The second DC charging port is connected to the power battery through the second switch module.

[0034] A possible implementation, where the second DC charging port is connected to the power battery, includes:

[0035] The second DC charging port is connected to the input end of the buck-boost module through the second switch module, and the output end of the first buck-boost module is connected to the power battery.

[0036] A possible implementation, where the charging system further includes a second buck-boost module. The input end of the second buck-boost module is connected to the second DC charging port through the second switch module, and the output end of the second buck-boost module is connected to the power battery. The second buck-boost module is used to boost or buck the output voltage of the second DC charging port and then transmit it to the power battery.

[0037] A possible implementation, where the control module is specifically configured to:

[0038] When the current maximum allowable charging current of the power battery is less than or equal to the first threshold, determine that the current maximum allowable charging current of the second DC charging port is the product of the first ratio and the result of subtracting the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

[0039] A possible implementation, where the control module is specifically configured to:

[0040] Determine that the current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second charging port and then minus the output current on the DC side of the on-vehicle charger.

[0041] A possible implementation, where the control module is specifically configured to:

[0042] When the current maximum allowable charging current of the power battery is greater than the first threshold, determine that the current maximum allowable charging current of the second DC charging port is the current maximum allowable charging current of the power battery minus the output current on the DC side of the on-vehicle charger and then minus the first preset value.

[0043] A possible implementation, where the control module is specifically configured to:

[0044] Determine that the current maximum allowable charging current of the first DC charging port is the minimum value between the maximum allowable current of the buck-boost module and the result of subtracting the current charging current of the second DC charging port and the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

[0045] A possible implementation, where the first threshold is 60 amperes.

[0046] A possible implementation, where the control module is specifically configured to:

[0047] When the current maximum allowable charging current of the power battery is less than or equal to the second threshold, determine that the current maximum allowable charging current of the second DC charging port is the result of multiplying the current maximum allowable charging current of the power battery by the second ratio and subtracting the output current of the DC side of the on-vehicle charger.

[0048] A possible implementation, where the control module is specifically configured to:

[0049] Determine that the current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second charging port minus the output current of the DC side of the on-vehicle charger.

[0050] A possible implementation, where the control module is specifically configured to:

[0051] When the current maximum allowable charging current of the power battery is greater than the second threshold, determine that the current maximum allowable charging current of the second DC charging port is the minimum value between the maximum charging current of the second DC charging port and the result of subtracting the output current of the DC side of the on-vehicle charger and the second preset value from the current maximum allowable charging current of the power battery.

[0052] A possible implementation, where the control module is specifically configured to:

[0053] Determine that the current maximum allowable charging current of the first DC charging port is the minimum value between the maximum charging current of the first DC charging port and the result of subtracting the current charging current of the second DC charging port and the output current of the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

[0054] A possible implementation, where the second threshold is 120 amperes.

[0055] In a third aspect, the present application provides an electric vehicle, including the charging system of the electric vehicle as described in the second aspect.

[0056] Implementing the present application will have the following beneficial effects: When switching from the single-gun DC charging mode to the double-gun DC charging mode, adjust the charging current of one charging gun according to the charging current of the other charging gun, so as to realize the timely and dynamic distribution of the current of each charging gun during the double-gun DC charging process, thereby shortening the charging time. Description of the Drawings

[0057] To more clearly illustrate the technical solutions in the present application or the prior art, the following will briefly introduce the accompanying drawings required for the description of the present application or the prior art. Obviously, the accompanying drawings in the following description are only some examples of the present application. For those of ordinary skill in the art, without creative efforts, other accompanying drawings can also be obtained based on these drawings. Among them:

[0058] Figure 1 FIG. is an application scenario diagram of single-gun to dual-gun DC charging control for an electric vehicle provided by the present application;

[0059] Figure 2 FIG. is a schematic structural diagram of a direct-connected boost charging system for an electric vehicle provided by the present application;

[0060] Figure 3 FIG. is a schematic structural diagram of a shared boost charging system for an electric vehicle provided by the present application;

[0061] Figure 4 FIG. is a schematic flowchart of direct-connected boost charging control for an electric vehicle provided by the present application;

[0062] Figure 5 FIG. is a schematic diagram of a dual-charging-port electric vehicle provided by the present application. Detailed implementation manners

[0063] In order to enable those skilled in the art of the present technology to better understand the solution of the present application, the following will clearly and completely describe the technical solutions in the present application in conjunction with the accompanying drawings in the present application. Obviously, the described examples are only a part of the examples of the present application, rather than all of them. Based on the examples in the present application, all other examples obtained by those of ordinary skill in the art without creative efforts belong to the scope protected by the present application.

[0064] The terms "1" and "2" etc. in the present application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally further includes steps or units not listed, or optionally further includes other steps or units inherent to these processes, methods, products or devices.

[0065] References to "embodiments" in this specification mean that a particular feature, structure, or characteristic described in connection with the embodiments can be included in at least one example of the present application. The phrase occurs in various places in the specification and is not necessarily intended to refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive of other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0066] Please refer to Figure 1 , Figure 1 which is an application scenario diagram of single-gun to dual-gun DC charging control for an electric vehicle provided by the present application. As Figure 1 shown, this application scenario diagram includes a user 101, a dual-charging-port electric vehicle 102, and a charging pile 103. It should be noted that Figure 1 the number of each device in the system shown, the form of each device, and the number of users are for illustration purposes and do not constitute a limitation to the present application. One user can use multiple dual-charging-port electric vehicles, and one user can use multiple charging piles.

[0067] Among them, the user 101 is the user who actually operates the dual-charging-port electric vehicle 102 to control the dual-charging-port electric vehicle 102 to perform corresponding operations. The dual-charging-port electric vehicle 102 can be Figure 1 the vehicle shown, or other small passenger cars, ordinary passenger cars, luxury passenger cars, and multi-purpose passenger cars, etc. The charging pile 103 can be fixed to the ground or wall and installed in public buildings, shopping malls, public parking lots, residential community parking lots, and charging stations, etc., and can charge various models of electric vehicles according to different voltage levels. The input end of the charging pile 103 is directly connected to the power grid, and the output end is equipped with a charging plug for charging the electric vehicle. The user can use a specific charging card to swipe on the man-machine interaction operation interface provided by the charging pile 103 to perform operations such as corresponding charging methods, charging times, and printing of fee data. The display screen of the charging pile 103 can display data such as the charging amount, fee, and charging time.

[0068] Please refer to Figure 2 , Figure 2 which is a schematic structural diagram of a direct connection boost charging system for an electric vehicle provided by the present application. As Figure 2As shown in the figure, the structural schematic diagram includes the following components: a first DC charging port 201, a buck-boost module 202, a power battery 203, a first switch module K1, a second switch module K2, a control unit 204, a second DC charging port 205, an AC charging port 206, and an on-vehicle charger 207. Specifically, the first DC charging port 201 is the first DC charging port in this embodiment, and the second DC charging port 205 is the second DC charging port in this embodiment. The first switch module K1 includes a first contactor K11 and a second contactor K12, and the second switch module K2 includes a third contactor K21 and a fourth contactor K22. The first DC charging port 201 is connected to the input end of the buck-boost module 202 through the first switch module K1. The output end of the buck-boost module 202 is connected to the power battery 203. The second DC charging port 205 is connected to the power battery 203. The first DC charging port 201 is connected to the control unit 204 through the first switch module K1. The second DC charging port 205 is connected to the control unit 204 through the second switch module K2. The control unit 204 is configured to determine the current maximum allowable charging current of the second DC charging port 205 based on the current maximum allowable charging current of the power battery 203 and the DC-side output current of the on-vehicle charger 207 when switching from the single-gun DC charging mode to the double-gun DC charging mode. The control unit 204 is further configured to determine the current maximum allowable charging current of the first DC charging port 201 based on the current maximum allowable charging current of the power battery 203, the current charging current of the second DC charging port 205, and the DC-side output current of the on-vehicle charger 207. In addition to the two DC charging ports, the electric vehicle in this application also has an AC charging function. The AC charging port 206 is connected to the input end of the on-vehicle charger 207, and the output end of the on-vehicle charger 207 is connected to the power battery 203. The AC charging process, the charging process of the first DC charging port 201, and the charging process of the second DC charging port 205 can be parallel. It should be noted that when preferentially using the direct-connected boost charging circuit for charging, the working life of the buck-boost circuit can be extended.

[0069] Please refer to Figure 3 , Figure 3 which is a structural schematic diagram of a shared boost charging system for an electric vehicle provided by this application. As Figure 3As shown in the figure, the structural schematic diagram includes the following components: a first DC charging port 201, a buck-boost module 202, a power battery 203, a first switch module K1, a second switch module K2, a control unit 204, a second DC charging port 205, an AC charging port 206, and an on-vehicle charger 207. Specifically, the first DC charging port 201 is the first DC charging port in this embodiment, the second DC charging port 205 is the second DC charging port in this embodiment, the first switch module K1 includes a first contactor K11 and a second contactor K12, and the second switch module K2 includes a third contactor K21 and a fourth contactor K22. The first DC charging port 201 is connected to the input end of the buck-boost module 202 through the first switch module K1, the output end of the buck-boost module 202 is connected to the power battery 203, the second DC charging port 205 is connected to the input end of the buck-boost module 202, the output end of the buck-boost module 202 is connected to the power battery 203, the first DC charging port 201 is connected to the control unit 204 through the first switch module K1, and the second DC charging port 205 is connected to the control unit 204 through the second switch module K2; the control unit 204 is configured to, when switching from the single-gun DC charging mode to the double-gun DC charging mode, determine the current maximum allowable charging current of the second DC charging port 205 based on the current maximum allowable charging current of the power battery 203 and the DC-side output current of the on-vehicle charger 207; the control unit 204 is further configured to determine the current maximum allowable charging current of the first DC charging port 201 based on the current maximum allowable charging current of the power battery 203, the current charging current of the second DC charging port 205, and the DC-side output current of the on-vehicle charger 207. It should be noted that in addition to the two DC charging ports, the electric vehicle in this application also has an AC charging function. The AC charging port 206 is connected to the input end of the on-vehicle charger 207, and the output end of the on-vehicle charger 207 is connected to the power battery 203. The AC charging process, the charging process of the first DC charging port 201, and the charging process of the second DC charging port 205 can be performed in parallel.

[0070] Please refer to Figure 4 , Figure 4 is a schematic flowchart of the direct connection and boost charging control of an electric vehicle provided by this application. Taking the process of applying this method to the direct connection and boost charging circuit of an electric vehicle as an example, the device of the schematic flowchart of the direct connection and boost charging circuit of the electric vehicle may include a server or an electronic device. It can be understood that the direct connection and boost charging control method in this embodiment can correspond to the above Figure 2 charging system. This method includes the following steps S401 - S402, where

[0071] S401: When switching from the single-gun DC charging mode to the double-gun DC charging mode, determine the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the DC-side output current of the on-vehicle charger.

[0072] In a possible example, step S401 includes the following steps A1 - A2,

[0073] A1: When the current maximum allowable charging current of the power battery is less than or equal to the first threshold, the current maximum allowable charging current of the second DC charging port is the product of the first ratio and the result of subtracting the output current on the DC side of the on - vehicle charger from the current maximum allowable charging current of the power battery.

[0074] Taking the first threshold as 60 A as an example, when the current maximum allowable charging current of the power battery ≤ 60 A, the current maximum allowable charging current of the second DC charging port = 0.5×(the current maximum allowable charging current of the power battery - the output current on the DC side of the on - vehicle charger). According to the current maximum allowable charging current of the power battery and the output current on the DC side of the on - vehicle charger, the current maximum allowable charging current of the second DC charging port is determined, optimizing the determination process of the current maximum allowable charging current of the second DC charging port.

[0075] Exemplarily, assuming the first threshold is 60 A, the current maximum allowable charging current of the power battery is 55 A, the output current on the DC side of the on - vehicle charger is 30 A, and the first ratio is 0.5, then the current maximum allowable charging current of the second DC charging port is: the result of 55 minus 30, and then multiplied by 0.5, getting 12.5.

[0076] A2: When the current maximum allowable charging current of the power battery is greater than the first threshold, the current maximum allowable charging current of the second DC charging port is the current maximum allowable charging current of the power battery minus the output current on the DC side of the on - vehicle charger minus the first preset value.

[0077] Taking the first threshold as 60 A and the first preset value as 30 as an example, when the current maximum allowable charging current of the power battery > 60 A, the current maximum allowable charging current of the second DC charging port = the current maximum allowable charging current of the power battery - the output current on the DC side of the on - vehicle charger - 30. Through the above steps, the adjustment efficiency of the current maximum allowable charging current of the second DC charging port is improved.

[0078] Exemplarily, assuming the first threshold is 60 A, the current maximum allowable charging current of the power battery is 108 A, the output current on the DC side of the on - vehicle charger is 48 A, the first preset value is 30 A, and the maximum allowable current of the buck - boost module is 40 A. The result of 108 minus 48 is 60, and 60 minus 30 gets 30. Then the current maximum allowable charging current of the second DC charging port is 30 A.

[0079] S402: Determine the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on - vehicle charger.

[0080] In a possible example, step S402 includes the following steps B1 - B2, where steps B1 - B2 can respectively correspond to steps A1 - A2 in the above step S401.

[0081] B1: The current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second charging port minus the DC - side output current of the on - vehicle charger.

[0082] Taking the first threshold as 60 A as an example, when the current maximum allowable charging current of the power battery ≤ 60 A, the current maximum allowable charging current of the first DC charging port = the current maximum allowable charging current of the power battery - the current charging current of the second DC charging port - the DC - side output current of the on - vehicle charger. Through the above steps, the dynamic adjustment efficiency of the current maximum allowable charging current of the first DC charging port is optimized.

[0083] Exemplarily, assuming the first threshold is 60 A, the current maximum allowable charging current of the power battery is 56 A, the current charging current of the second DC charging port is 20 A, and the DC - side output current of the on - vehicle charger is 10 A, then the current maximum allowable charging current of the first DC charging port is: 56 minus 20 and then minus 10, resulting in 26.

[0084] B2: The current maximum allowable charging current of the first DC charging port is the minimum value between the maximum allowable current of the buck - boost module and the result of the current maximum allowable charging current of the power battery minus the current charging current of the second DC charging port minus the DC - side output current of the on - vehicle charger.

[0085] Taking the first threshold as 60 A as an example, when the current maximum allowable charging current of the power battery > 60 A, the current maximum allowable charging current of the first DC charging port = min{the maximum allowable current of the buck - boost module, the current maximum allowable charging current of the power battery - the current charging current of the second DC charging port - the DC - side output current of the on - vehicle charger}. Through the above steps, the adjustment efficiency of the current maximum allowable charging current of the first DC charging port is improved.

[0086] Exemplarily, assuming the first threshold is 60 A, the current maximum allowable charging current of the power battery is 108 A, the current charging current of the second DC charging port is 48 A, the DC - side output current of the on - vehicle charger is 30 A, and the maximum allowable current of the buck - boost module is 40 A. The result of 108 minus 48 is 60, and 60 minus 30 gives 30. Then the current maximum allowable charging current of the first DC charging port is 30 A.

[0087] It can be understood that Figure 4 the shown direct - connection boost charging control method for electric vehicles can also correspond to the above Figure 3The shared boost charging system, the method may include the following steps S501 - S502, where

[0088] S501: When switching from the single-gun DC charging mode to the double-gun DC charging mode, determine the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current of the DC side of the on-vehicle charger.

[0089] In a possible example, step S501 includes the following steps C1 - C2

[0090] C1: When the current maximum allowable charging current of the power battery is less than or equal to the second threshold, the current maximum allowable charging current of the second DC charging port is the result of multiplying the second ratio by the difference between the current maximum allowable charging current of the power battery and the output current of the DC side of the on-vehicle charger.

[0091] Taking the second threshold as 120 A as an example, when the current maximum allowable charging current of the power battery ≤ 120 A, the current maximum allowable charging current of the second DC charging port = 0.5×(the current maximum allowable charging current of the power battery - the output current of the DC side of the on-vehicle charger). Through the above steps, the adjustment process of the current maximum allowable charging current of the second DC charging port is improved.

[0092] Exemplarily, assuming the second threshold is 120 A, the current maximum allowable charging current of the power battery is 114 A, the output current of the DC side of the on-vehicle charger is 54 A, and the second ratio is 0.5. The current maximum allowable charging current of the second DC charging port is: the result of 114 minus 54 is 60, and 60 multiplied by 0.5 gives 30. So the current maximum allowable charging current of the second DC charging port is 30 A.

[0093] C2: When the current maximum allowable charging current of the power battery is greater than the second threshold, the current maximum allowable charging current of the second DC charging port is the minimum value among the maximum charging current of the second DC charging port and the result of subtracting the second preset value from the difference between the current maximum allowable charging current of the power battery and the output current of the DC side of the on-vehicle charger.

[0094] Taking the second threshold as 120 A and the second preset value as 60 as an example, when the current maximum allowable charging current of the power battery > 120 A, the current maximum allowable charging current of the second DC charging port = min{(the current maximum allowable charging current of the power battery - the output current of the DC side of the on-vehicle charger - 60), the maximum charging current of the second DC charging port}. Through the above steps, the acquisition process of the current maximum allowable charging current of the second DC charging port is improved.

[0095] Exemplarily, assume that the second threshold is 120 A, the current maximum allowable charging current of the power battery is 122 A, the output current on the DC side of the on-vehicle charger is 40 A, the second preset value is 60 A, and the maximum charging current of the second DC charging port is 30 A. The result of 122 minus 40 minus 60 is 22. Since 22 is less than 30, the current maximum allowable charging current of the second DC charging port is 22 A.

[0096] S502: Determine the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger.

[0097] In a possible example, step S502 includes the following steps D1 - D2, where steps D1 - D2 can respectively correspond to steps C1 - C2 in the above step S501.

[0098] D1: The current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second DC charging port minus the output current on the DC side of the on-vehicle charger.

[0099] Taking the second threshold of 120 A as an example, when the current maximum allowable charging current of the power battery ≤ 120 A, the current maximum allowable charging current of the first DC charging port = the current maximum allowable charging current of the power battery - the current charging current of the second DC charging port - the output current on the DC side of the on-vehicle charger. Through the above steps, the regulation efficiency of the current maximum allowable charging current of the first DC charging port is improved.

[0100] Exemplarily, assume that the second threshold is 120 A, the current maximum allowable charging current of the power battery is 118 A, the output current on the DC side of the on-vehicle charger is 40 A, and the maximum charging current of the second DC charging port is 30 A. The result of 118 minus 40 minus 30 is 48. So the current maximum allowable charging current of the second DC charging port is 48 A.

[0101] D2: The current maximum allowable charging current of the first DC charging port is the minimum value between the maximum charging current of the first DC charging port and the result of the current maximum allowable charging current of the power battery minus the current charging current of the second DC charging port minus the output current on the DC side of the on-vehicle charger.

[0102] Taking the second threshold of 120 A as an example, when the current maximum allowable charging current of the power battery > 120 A, the current maximum allowable charging current of the first DC charging port = min{the current maximum allowable charging current of the power battery - the current charging current of the second DC charging port - the output current on the DC side of the on-vehicle charger, the maximum charging current of the first DC charging port}. Through the above steps, the regulation efficiency of the current maximum allowable charging current of the first DC charging port is improved.

[0103] Exemplarily, assume that the second threshold is 120 A, the current maximum allowable charging current of the power battery is 122 A, the output current of the DC side of the on-vehicle charger is 40 A, the maximum charging current of the first DC charging port is 60 A, and the maximum charging current of the first DC charging port is 30 A. The result of 122 minus 40 minus 60 is 22. Since 22 is less than 30, the current maximum allowable charging current of the second DC charging port is 22 A.

[0104] Please refer to Figure 5 , Figure 5 a schematic diagram of an electric vehicle with a dual charging port provided by the present application. As Figure 5 shown, the present application provides a vehicle, which can be an electric vehicle including a charging system. When the charging system is applied to power-consuming devices such as charging a vehicle with a dual charging gun, the charging current of one charging gun can be adjusted according to the charging current of the other charging gun, and the current can be dynamically allocated in real time to achieve the purpose of shortening the charging time.

[0105] In the description of the embodiments of the present application, it should be noted that terms such as "first" and "second" are used to distinguish identical or similar items with basically the same function. Those skilled in the art can understand that terms such as "first" and "second" do not limit the quantity and execution order, and "first" and "second" do not necessarily mean different. Therefore, it should not be construed as a limitation to the present application. The above-disclosed is only a preferred embodiment of the present application. Of course, the scope of the rights of the present application cannot be limited thereby. Those of ordinary skill in the art can understand all or part of the processes of implementing the above embodiments, and the equivalent changes made according to the claims of the present application still fall within the scope covered by the present application.

Claims

1. A method for charging control of an electric vehicle, characterized in that, it is applied to a charging system of an electric vehicle with dual DC charging ports. The charging system includes a first DC charging port, a second DC charging port, a first switching module, a second switching module, a first buck-boost module, an on-vehicle charger, a control module, and a power battery. The first DC charging port is connected to the input end of the buck-boost module through the first switching module, the output end of the buck-boost module is connected to the power battery, and the second DC charging port is connected to the power battery through the second switching module. The method includes: When switching from the single-gun DC charging mode to the dual-gun DC charging mode, determine the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger; Determine the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger.

2. The method according to claim 1, characterized in that, the determining the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger includes: When the current maximum allowable charging current of the power battery is less than or equal to a first threshold, the current maximum allowable charging current of the second DC charging port is the product of a first ratio and the result of subtracting the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

3. The method according to claim 1, characterized in that, the determining the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger includes: When the current maximum allowable charging current of the power battery is less than or equal to a first threshold, the current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second charging port and then minus the output current on the DC side of the on-vehicle charger.

4. The method according to claim 1, characterized in that, the determining the current maximum allowable charging current of the second DC charging port according to the current maximum allowable charging current of the power battery and the output current on the DC side of the on-vehicle charger includes: When the current maximum allowable charging current of the power battery is greater than a first threshold, the current maximum allowable charging current of the second DC charging port is the current maximum allowable charging current of the power battery minus the output current on the DC side of the on-vehicle charger and then minus a first preset value.

5. The method according to claim 1, characterized in that, the determining the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port, and the output current on the DC side of the on-vehicle charger includes: When the current maximum allowable charging current of the power battery is greater than the first threshold, the current maximum allowable charging current of the first DC charging port is the minimum value among the maximum allowable current of the buck-boost module, the result of subtracting the current charging current of the second DC charging port and the DC side output current of the on-vehicle charger from the current maximum allowable charging current of the power battery.

6. The method according to any one of claims 2-5, characterized in that, the first threshold is 60 A.

7. The method according to claim 6, characterized in that, determining the current maximum allowable charging current of the first DC charging port according to the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port and the DC side output current of the on-vehicle charger includes: When the current maximum allowable charging current of the power battery is greater than the second threshold, the current maximum allowable charging current of the first DC charging port is the minimum value among the maximum charging current of the first DC charging port, the result of subtracting the current charging current of the second DC charging port and the DC side output current of the on-vehicle charger from the current maximum allowable charging current of the power battery.

8. The method according to claim 7, characterized in that, the second threshold is 120 A.

9. A charging system for an electric vehicle, characterized in that, comprising a first DC charging port, a second DC charging port, a first switching module, a second switching module, a first buck-boost module, an on-vehicle charger, a control module and a power battery, wherein: The first DC charging port is connected to the input end of the buck-boost module through the first switching module, the output end of the buck-boost module is connected to the power battery, the second DC charging port is connected to the power battery, the first DC charging port is connected to the control module through the first switching module, and the second DC charging port is connected to the control module through the second switching module; The control module is configured to determine the current maximum allowable charging current of the second DC charging port based on the current maximum allowable charging current of the power battery and the DC side output current of the on-vehicle charger when switching from the single-gun DC charging mode to the double-gun DC charging mode; The control module is further configured to determine the current maximum allowable charging current of the first DC charging port based on the current maximum allowable charging current of the power battery, the current charging current of the second DC charging port and the DC side output current of the on-vehicle charger.

10. The charging system according to claim 9, characterized in that, the connection of the second DC charging port to the power battery includes: The second DC charging port is connected to the power battery through the second switching module.

11. The charging system according to claim 10, characterized in that, the connection of the second DC charging port to the power battery includes: The second DC charging port is connected to the input end of the buck-boost module through the second switching module, and the output end of the first buck-boost module is connected to the power battery.

12. The charging system according to claim 11, characterized in that, The charging system further includes a second buck-boost module. The input end of the second buck-boost module is connected to the second DC charging port through the second switch module, and the output end of the second buck-boost module is connected to the power battery. The second buck-boost module is configured to boost or buck the output voltage of the second DC charging port and then transmit it to the power battery.

13. The charging system according to claim 12, wherein, the control module is specifically configured to: when the current maximum allowable charging current of the power battery is less than or equal to a first threshold, determine that the current maximum allowable charging current of the second DC charging port is the product of a first ratio and the result of subtracting the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

14. The charging system according to claim 13, wherein, the control module is specifically configured to: determine that the current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second charging port and then minus the output current on the DC side of the on-vehicle charger.

15. The charging system according to claim 14, wherein, the control module is specifically configured to: when the current maximum allowable charging current of the power battery is greater than the first threshold, determine that the current maximum allowable charging current of the second DC charging port is the current maximum allowable charging current of the power battery minus the output current on the DC side of the on-vehicle charger and then minus a first preset value.

16. The charging system according to claim 15, wherein, the control module is specifically configured to: determine that the current maximum allowable charging current of the first DC charging port is the minimum value between the maximum allowable current of the buck-boost module and the result of subtracting the current charging current of the second DC charging port and the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

17. The charging system according to claim 16, wherein, the first threshold is 60 A.

18. The charging system according to claim 17, wherein, the control module is specifically configured to: when the current maximum allowable charging current of the power battery is less than or equal to a second threshold, determine that the current maximum allowable charging current of the second DC charging port is the product of a second ratio and the result of subtracting the output current on the DC side of the on-vehicle charger from the current maximum allowable charging current of the power battery.

19. The charging system according to claim 18, wherein, the control module is specifically configured to: determine that the current maximum allowable charging current of the first DC charging port is the current maximum allowable charging current of the power battery minus the current charging current of the second charging port and then minus the output current on the DC side of the on-vehicle charger.

20. The charging system according to claim 19, wherein, the control module is specifically configured to: When the current maximum allowable charging current of the power battery is greater than the second threshold, determine the current maximum allowable charging current of the second DC charging port as the minimum value among the maximum charging current of the second DC charging port, the current maximum allowable charging current of the power battery minus the DC side output current of the on-vehicle charger minus a second preset value.

21. The charging system according to claim 20, wherein, the control module is specifically configured to: determine the current maximum allowable charging current of the first DC charging port as the minimum value among the maximum charging current of the first DC charging port and the result of the current maximum allowable charging current of the power battery minus the current charging current of the second DC charging port minus the DC side output current of the on-vehicle charger.

22. The charging system according to claim 21, wherein, the second threshold is 120 A.

23. An electric vehicle, wherein, it includes the charging system of the electric vehicle according to any one of claims 9 to 22.

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