Power supply system and charging method of new energy automobile and new energy automobile

Abstract

The invention discloses a power supply system and a charging method of a new energy automobile and the new energy automobile, and belongs to the technical field of new energy. Determining a charging mode; if the battery pack is in the overcharge mode, the BMS controls the first switching relay group to be closed, so that the battery pack is configured into two battery branches which are connected in parallel to be connected into a main loop, and each battery branch comprises three single-pack batteries; the main loop relay group and the charging relay group are controlled to be closed, so that the charging module charges the two battery branches through the main loop; if the battery pack is in the general charging mode, the BMS controls the second switching relay set to be closed, so that the battery pack is configured into three battery branches connected in parallel to be connected into the main loop, and each battery branch comprises two single-pack batteries; and the main loop relay group and the charging relay group are controlled to be closed, so that the charging module charges the three battery branches through the main loop. Switching between high-voltage charging and low-voltage charging can be achieved, the charging time can be shortened, and the cost can be reduced.

Description

Technical Field

[0001] The present application relates to the field of new energy technology, and in particular to a power supply system and a charging method for a new energy vehicle and a new energy vehicle. Background Art

[0002] At present, the common electrical appliances in new energy vehicles are 600V platforms. When the power of new energy vehicles increases, the required current increases accordingly, and the copper busbar's current capacity needs to be increased to meet the high current demand. However, the increase in the copper busbar's current capacity is not endless, which affects the charging capacity of the entire vehicle, resulting in a charging time that cannot meet customer needs.

[0003] High-voltage platforms, such as 800V, 1000V, etc., are usually used for high-current charging. However, the electrical appliances corresponding to the high-voltage platforms have not been fully popularized and are still in the research and development stage, which can easily lead to a sharp increase in the cost of new energy vehicles. Summary of the invention

[0004] The present application provides a power supply system, a charging method and a new energy vehicle for a new energy vehicle, which are used to solve the problem that the charging time is long when charging using a low voltage platform, and the high voltage platform needs to develop high voltage resistant electrical appliances, which increases the cost. The technical solution is as follows:

[0005] According to a first aspect of the present application, a power supply system for a new energy vehicle is provided, the power supply system comprising a battery pack and a power distribution module, the battery pack comprising six single-pack batteries, the power distribution module comprising a battery management system BMS and a plurality of relay groups, the plurality of relay groups comprising a first switching relay group, a second switching relay group, a main circuit relay group and a charging relay group;

[0006] The BMS is used to determine the current charging mode according to the highest charging voltage supported by the charging pile after determining that the new energy vehicle is connected to the charging pile;

[0007] If the charging mode is the supercharging mode, the BMS is further used to control the first switching relay group to close, so that the battery pack is configured as two parallel battery branches connected to the main circuit, each battery branch includes three single-pack batteries; and control the main circuit relay group and the charging relay group to close, so that the charging module charges the two battery branches through the main circuit;

[0008] If the charging mode is the general charging mode, the BMS is also used to control the second switching relay group to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and control the main circuit relay group and the charging relay group to close, so that the charging module charges the three battery branches through the main circuit.

[0009] In a possible implementation, the BMS is further configured to enter a discharge mode after determining that the new energy vehicle is not connected to the charging pile;

[0010] The BMS is also used to control the closure of the second switching relay group so that the battery pack is configured as three parallel battery branches connected to the main circuit, each battery branch includes two single-pack batteries; and control the closure of the main circuit relay group so that the three battery branches discharge to the electrical appliances in the new energy vehicle through the main circuit.

[0011] In one possible implementation, the BMS is also used to control the second switching relay group to close when the new energy vehicle is driving and energy recovery is required, so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and control the main circuit relay group and the charging relay group to close, so that the recovered energy can charge the three battery branches through the main circuit.

[0012] In a possible implementation, the battery pack includes first to sixth single-pack batteries, the first switching relay group includes first to fourth relays, and the first switching relay group is closed;

[0013] The negative electrode of the first battery pack is connected to the positive electrode of the second battery pack, the negative electrode of the second battery pack is connected to the first end of the first relay, the second end of the first relay is connected to the positive electrode of the third battery pack, the negative electrode of the third battery pack is connected to the first end of the second relay, the second end of the second relay is connected to the first negative end of the main circuit as the negative electrode of the first battery branch, and the positive electrode of the first battery pack is connected to the first positive end of the main circuit as the positive electrode of the first battery branch;

[0014] The negative electrode of the fourth single-pack battery is connected to the first end of the third relay, the second end of the third relay is connected to the positive electrode of the fifth single-pack battery, the negative electrode of the fifth single-pack battery is connected to the positive electrode of the sixth single-pack battery, the negative electrode of the sixth single-pack battery is connected to the first negative end of the main circuit as the negative electrode of the second battery branch, the positive electrode of the fourth single-pack battery is connected to the first end of the fourth relay, and the second end of the fourth relay is connected to the first positive end of the main circuit as the positive electrode of the second battery branch.

[0015] In a possible implementation, the battery pack includes first to sixth single-pack batteries, the second switching relay group includes fifth to ninth relays, and the second switching relay group is closed;

[0016] The negative electrode of the first battery pack is connected to the positive electrode of the second battery pack, the negative electrode of the second battery pack is connected to the first end of the fifth relay, the second end of the fifth relay is connected to the first negative end of the main circuit as the negative electrode of the third battery branch, and the positive electrode of the first battery pack is connected to the first positive end of the main circuit as the positive electrode of the third battery branch;

[0017] The negative electrode of the third battery pack is connected to the first end of the sixth relay, the second end of the sixth relay is connected to the positive electrode of the fourth battery pack, the negative electrode of the fourth battery pack is connected to the first end of the seventh relay, the second end of the seventh relay is connected to the first negative end of the main circuit as the negative electrode of the fourth battery branch, the positive electrode of the third battery pack is connected to the first end of the eighth relay, and the second end of the eighth relay is connected to the first positive end of the main circuit as the positive electrode of the fourth battery branch;

[0018] The negative electrode of the fifth single-pack battery is connected to the positive electrode of the sixth single-pack battery, and the negative electrode of the sixth single-pack battery is connected to the first negative terminal of the main circuit as the negative electrode of the fifth battery branch. The positive electrode of the fifth single-pack battery is connected to the first terminal of the ninth relay, and the second terminal of the ninth relay is connected to the first positive terminal of the main circuit as the positive electrode of the fifth battery branch.

[0019] In a possible implementation, the main circuit relay group includes a tenth relay and an eleventh relay;

[0020] The first end of the tenth relay serves as the first negative end of the main circuit, and the second end of the tenth relay serves as the second negative end of the main circuit;

[0021] The first end of the eleventh relay serves as the first positive end of the main circuit, and the second end of the eleventh relay serves as the second positive end of the main circuit.

[0022] In a possible implementation, the main circuit relay group further includes a twelfth relay and a pre-charging module;

[0023] The first end of the twelfth relay is connected to the first end of the eleventh relay and serves as the first positive end of the main circuit;

[0024] The second end of the twelfth relay is connected to the first end of the pre-charging module;

[0025] The second end of the pre-charging module is connected to the second end of the eleventh relay and serves as the second positive end of the main circuit.

[0026] In a possible implementation, the charging relay group includes thirteenth to sixteenth relays;

[0027] The first ends of the thirteenth relay and the fourteenth relay are respectively connected to the second negative end of the main circuit, and the second ends of the thirteenth relay and the fourteenth relay are respectively connected to the negative electrodes of the two charging modules;

[0028] The first ends of the fifteenth relay and the sixteenth relay are respectively connected to the second positive end of the main circuit, and the second ends of the fifteenth relay and the sixteenth relay are respectively connected to the positive poles of the two charging modules.

[0029] According to a second aspect of the present application, a charging method for a new energy vehicle is provided, which is used in the power supply system as described above, and the method comprises:

[0030] After determining that the new energy vehicle is connected to a charging pile, determining the current charging mode according to the highest charging voltage supported by the charging pile;

[0031] If the charging mode is the supercharging mode, the first switching relay group is controlled to be closed, so that the battery pack is configured as two parallel battery branches connected to the main circuit, each battery branch includes three single-pack batteries; and the main circuit relay group and the charging relay group are controlled to be closed, so that the charging module charges the two battery branches through the main circuit;

[0032] If the charging mode is the general charging mode, the second switching relay group is controlled to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and the main circuit relay group and the charging relay group are controlled to close so that the charging module charges the three battery branches through the main circuit.

[0033] According to a third aspect of the present application, a computer-readable storage medium is provided, in which at least one instruction is stored. The at least one instruction is loaded and executed by a processor to implement the power supply method for a new energy vehicle as described above.

[0034] According to a fourth aspect of the present application, a new energy vehicle is provided, and the new energy vehicle includes the power supply system of the new energy vehicle described above.

[0035] The beneficial effects of the technical solution provided by this application include at least:

[0036] If the charging pile supports supercharging mode (900V), the battery pack will be configured as two parallel battery branches connected to the main circuit for charging. Each battery branch includes three single-pack batteries, which can achieve high-voltage charging, reducing both the charging time and the use of copper busbar current capacity. If the charging pile supports normal charging mode (600V), the battery pack will be configured as three parallel battery branches connected to the main circuit for charging. Each battery branch includes two single-pack batteries, which can achieve low-voltage charging, so that it can be adapted to all charging piles for charging without increasing costs.

[0037] If the discharge mode is entered, the battery pack will be configured as three parallel battery branches and connected to the main circuit for discharge. Each battery branch includes two single-pack batteries, which can achieve low-voltage discharge. There is no need to develop high-voltage resistant electrical appliances, which can reduce the cost of new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0039] Figure 1 is a structural schematic diagram of a power supply system for a new energy vehicle according to an embodiment of the present application;

[0040] Figure 2 is a schematic diagram of the closing sequence of relays during the charging and discharging process provided by an embodiment of the present application;

[0041] Figure 3 This is a flow chart of a method for powering a new energy vehicle provided in one embodiment of the present application. DETAILED DESCRIPTION

[0042] In order to make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the implementation methods of the present application will be further described in detail below in conjunction with the accompanying drawings.

[0043] like Figure 1 As shown, it shows a structural block diagram of a power supply system for a new energy vehicle provided by an embodiment of the present application, and the power supply system for a new energy vehicle can be applied to a new energy vehicle. The power supply system for a new energy vehicle can include a battery pack and a power distribution module.

[0044] Among them, the battery pack includes multiple single-pack batteries, and the number of single-pack batteries can be set according to actual needs. The battery pack in this embodiment includes six single-pack batteries, which are respectively recorded as P1, P2, P3, P4, P5 and P6, and each single-pack battery has the same voltage platform, such as a 300V voltage platform, of course, it can also be other values. The battery pack has independent high-voltage output capability, and an acquisition board is provided inside it, which can monitor the state of the battery cell in real time, such as battery voltage, temperature, etc., and send the state of the battery cell to the battery management system (Battery Management System, BMS) in the power distribution module, so that the BMS can determine whether the battery is in a fully charged state (i.e., fully charged) or fully discharged state (i.e., discharged), and can also determine whether the battery is faulty.

[0045] The power distribution module includes a BMS and multiple relay groups. The BMS includes a high-voltage board and a main board. The high-voltage board is responsible for collecting loop voltage and current, and the main board is responsible for fault diagnosis and logic control, such as controlling the opening and closing of relays.

[0046] The multiple relay groups include a first switching relay group, a second switching relay group, a main circuit relay group and a charging relay group. The first switching relay group is used to switch to a high-voltage charging platform, the second switching relay group is used to switch to a low-voltage charging platform, the main circuit relay is used to connect the main circuit, and the charging relay group is used to charge through the main circuit.

[0047] The charging principle of new energy vehicles is explained below.

[0048] After starting a new energy vehicle, when the vehicle control unit (VCU) detects that the vehicle's key status is KEY ON, it wakes up the BMS and battery pack, and the BMS and battery pack perform self-inspection. The battery pack sends the cell status and fault information to the BMS for the BMS to make a judgment.

[0049] BMS is used to determine the current charging mode according to the highest charging voltage supported by the charging pile after confirming that the new energy vehicle is connected to the charging pile. Specifically, BMS detects whether the plug-in signal CC2 and A+ exist at the same time. If the plug-in signal CC2 and A+ exist at the same time, it is determined that the new energy vehicle is connected to the charging pile and enters the charging mode; if the plug-in signal CC2 and A+ do not exist at the same time, it is determined that the new energy vehicle is not connected to the charging pile and enters the discharge mode.

[0050] After the new energy vehicle is connected to the charging pile, the charging pile will send an identification message to the BMS. The BMS determines the highest charging voltage supported by the charging pile based on the identification message, and determines the current charging mode based on the highest charging voltage. Among them, the charging mode includes supercharging mode and general charging mode. The charging voltage of the supercharging mode is higher than the charging voltage of the general charging mode. In this embodiment, the charging voltage of the supercharging mode is about 900V, and the charging voltage of the general charging mode is about 600V.

[0051] Assuming that the identification message indicates that the maximum charging voltage supported by the charging pile is 1000V, the BMS determines that the charging mode is the supercharging mode; if the identification message indicates that the maximum charging voltage supported by the charging pile is 800V, the BMS determines that the charging mode is the normal charging mode.

[0052] (1) If the charging mode is the supercharge mode, the BMS is also used to control the first switching relay group to close so that the battery pack is configured as two parallel battery branches connected to the main circuit, each battery branch includes three single-pack batteries; and control the main circuit relay group and the charging relay group to close so that the charging module charges the two battery branches through the main circuit. That is, the single-pack batteries P1, P2 and P3 form the first battery branch, and the single-pack batteries P4, P5 and P6 form the second battery branch. These two battery branches are connected in parallel to the main circuit, and the charging module charges the two battery branches through the main circuit.

[0053] Specifically, the battery pack includes first to sixth single pack batteries, the first switching relay group includes first to fourth relays, and the first switching relay group is closed;

[0054] The circuit structure of the first battery branch is as follows: the negative electrode of the first single-pack battery P1 is connected to the positive electrode of the second single-pack battery P2, the negative electrode of the second single-pack battery P2 is connected to the first end of the first relay K9, the second end of the first relay K9 is connected to the positive electrode of the third single-pack battery P3, the negative electrode of the third single-pack battery P3 is connected to the first end of the second relay K5, the second end of the second relay K5 is connected to the first negative end of the main circuit as the negative electrode of the first battery branch, and the positive electrode of the first single-pack battery P1 is connected to the first positive end of the main circuit as the positive electrode of the first battery branch. That is to say, the first single-pack battery P1, the second single-pack battery P2, the first relay K9, the third single-pack battery P3, and the second relay K5 constitute the first battery branch, and the positive electrode of the first single-pack battery P1 is the positive electrode of the first battery branch ( Figure 1 The second end of the second relay K5 is the negative electrode of the first battery branch ( Figure 1 Indicated by black line).

[0055] The circuit structure of the second battery branch is as follows: the negative electrode of the fourth battery pack P4 is connected to the first end of the third relay K11, the second end of the third relay K11 is connected to the positive electrode of the fifth battery pack P5, the negative electrode of the fifth battery pack P5 is connected to the positive electrode of the sixth battery pack P6, the negative electrode of the sixth battery pack P6 is connected to the first negative end of the main circuit as the negative electrode of the second battery branch, the positive electrode of the fourth battery pack P4 is connected to the first end of the fourth relay K6, and the second end of the fourth relay K6 is connected to the first positive end of the main circuit as the positive electrode of the second battery branch. In other words, the fourth relay K6, the fourth battery pack P4, the third relay K11, the fifth battery pack P5, and the sixth battery pack P6 constitute the second battery branch, and the second end of the fourth relay K6 is the positive electrode of the second battery branch ( Figure 1 The negative electrode of the sixth single pack battery P6 is the negative electrode of the second battery branch ( Figure 1 Indicated by black line).

[0056] Optionally, a current sensor can be connected in series between the sixth battery pack P6 and the main circuit, that is, the negative electrode of the sixth battery pack P6 is connected to the first end of the current sensor, and the second end of the current sensor is connected to the first negative end of the main circuit as the negative electrode of the second battery branch.

[0057] In this embodiment, the main circuit relay group includes the tenth relay K2 and the eleventh relay K1; the first end of the tenth relay K2 serves as the first negative end of the main circuit, and the second end serves as the second negative end of the main circuit; the first end of the eleventh relay K1 serves as the first positive end of the main circuit, and the second end serves as the second positive end of the main circuit. That is, the positive electrode of the first single-pack battery P1 in the first battery branch is connected to the first end of the eleventh relay K1, and the second end of the second relay K5 is connected to the first end of the tenth relay K2. The second end of the fourth relay K6 in the second battery branch is connected to the first end of the eleventh relay K1, and the negative electrode of the sixth single-pack battery P6 is connected to the first end of the tenth relay K2.

[0058] After the BMS detects that all relays in the first switching relay group have been closed, it controls the relays in the main circuit relay group to be closed. The BMS first controls the tenth relay K2 to be closed, and then controls the eleventh relay K1 to be closed.

[0059] After closing the eleventh relay K1, a large current will be instantly generated on the eleventh relay K1, which may damage the back-end devices. Therefore, we can set a pre-charging circuit for the eleventh relay K1 to reduce the large current at the moment of closing. Specifically, the main circuit relay group also includes the twelfth relay K12 and a pre-charging module; the first end of the twelfth relay K12 is connected to the first end of the eleventh relay K1 and serves as the first positive end of the main circuit; the second end of the twelfth relay K12 is connected to the first end of the pre-charging module; the second end of the pre-charging module is connected to the second end of the eleventh relay K1 and serves as the second positive end of the main circuit. Among them, the pre-charging module can be a capacitor module.

[0060] If there is a pre-charging circuit, after the BMS detects that all relays in the first switching relay group are closed, it first controls the tenth relay K2 to close, and pre-charges the pre-charging module through the twelfth relay K12. After the pre-charging is completed, the eleventh relay K1 is controlled to close. Among them, the BMS can determine that the pre-charging is completed after waiting for T time, and T can be calculated based on the back-end capacitance and charging time.

[0061] In this embodiment, the charging relay group includes thirteenth to sixteenth relays K15; the first ends of the thirteenth relay K14 and the fourteenth relay K16 are respectively connected to the second negative end of the main circuit, and the second ends of the thirteenth relay K14 and the fourteenth relay K16 are respectively connected to the negative poles of the two charging modules; the first ends of the fifteenth relay K13 and the sixteenth relay K15 are respectively connected to the second positive end of the main circuit, and the second ends of the fifteenth relay K13 and the sixteenth relay K15 are respectively connected to the positive poles of the two charging modules.

[0062] That is to say, the first ends of the thirteenth relay K14 and the fourteenth relay K16 are respectively connected to the second end of the tenth relay K2, and the first ends of the fifteenth relay K13 and the sixteenth relay K15 are respectively connected to the second end of the eleventh relay K1. The second end of the fifteenth relay K13 is connected to the positive pole of the charging module 1, and the second end of the thirteenth relay K14 is connected to the negative pole of the charging module 1. The second end of the sixteenth relay K15 is connected to the positive pole of the charging module 2, and the second end of the fourteenth relay K16 is connected to the negative pole of the charging module 2.

[0063] After the BMS detects that all relays in the main circuit relay group have been closed, it controls the relays in the charging relay group to be closed. The BMS first controls the thirteenth relay K14 and the fourteenth relay K16 to be closed, and then controls the fifteenth relay K13 and the sixteenth relay K15 to be closed.

[0064] At this point, the first battery branch and the second battery branch connected in parallel, the main circuit and the two charging circuits are connected, and the battery pack can be charged with high voltage through the charging module.

[0065] (2) If the charging mode is the general charging mode, the BMS is also used to control the second switching relay group to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, each battery branch includes two single-pack batteries; and control the main circuit relay group and the charging relay group to close so that the charging module charges the three battery branches through the main circuit. That is, the single-pack batteries P1 and P2 form the third battery branch, the single-pack batteries P3 and P4 form the fourth battery branch, and the single-pack batteries P5 and P6 form the fifth battery branch. These three battery branches are connected in parallel to the main circuit, and the charging module charges the three battery branches through the main circuit.

[0066] Specifically, the battery pack includes first to sixth single pack batteries, the second switching relay group includes fifth to ninth relays, and the second switching relay group is closed;

[0067] The circuit structure of the third battery branch is as follows: the negative electrode of the first battery pack P1 is connected to the positive electrode of the second battery pack P2, the negative electrode of the second battery pack P2 is connected to the first end of the fifth relay K3, the second end of the fifth relay K3 is connected to the first negative end of the main circuit as the negative electrode of the third battery branch, and the positive electrode of the first battery pack P1 is connected to the first positive end of the main circuit as the positive electrode of the third battery branch. That is to say, the first battery pack P1, the second battery pack P2, and the fifth relay K3 form the third battery branch, and the positive electrode of the first battery pack P1 is the positive electrode of the third battery branch ( Figure 1 The second end of the fifth relay K3 is the negative electrode of the third battery branch ( Figure 1 Indicated by black line).

[0068] The circuit structure of the fourth battery branch is as follows: the negative electrode of the third single-pack battery P3 is connected to the first end of the sixth relay K10, the second end of the sixth relay K10 is connected to the positive electrode of the fourth single-pack battery P4, the negative electrode of the fourth single-pack battery P4 is connected to the first end of the seventh relay K7, the second end of the seventh relay K7 is connected to the first negative end of the main circuit as the negative electrode of the fourth battery branch, the positive electrode of the third single-pack battery P3 is connected to the first end of the eighth relay K4, and the second end of the eighth relay K4 is connected to the first positive end of the main circuit as the positive electrode of the fourth battery branch. In other words, the eighth relay K4, the third single-pack battery P3, the sixth relay K10, the fourth single-pack battery P4, and the seventh relay K7 constitute the fourth battery branch, and the second end of the eighth relay K4 is the positive electrode of the fourth battery branch ( Figure 1 The second end of the seventh relay K7 is the negative electrode of the fourth battery branch ( Figure 1Indicated by black line).

[0069] The circuit structure of the fifth battery branch is as follows: the negative electrode of the fifth battery pack P5 is connected to the positive electrode of the sixth battery pack P6, the negative electrode of the sixth battery pack P6 is connected to the first negative terminal of the main circuit as the negative electrode of the fifth battery branch, the positive electrode of the fifth battery pack P5 is connected to the first terminal of the ninth relay K8, and the second terminal of the ninth relay K8 is connected to the first positive terminal of the main circuit as the positive electrode of the fifth battery branch. That is to say, the ninth relay K8, the fifth battery pack P5, and the sixth battery pack P6 constitute the fifth battery branch, and the second terminal of the ninth relay K8 is the positive electrode of the fifth battery branch ( Figure 1 The negative electrode of the sixth single pack battery P6 is the negative electrode of the fifth battery branch ( Figure 1 Indicated by black line).

[0070] Optionally, a current sensor can be connected in series between the sixth battery pack P6 and the main circuit, that is, the negative electrode of the sixth battery pack P6 is connected to the first end of the current sensor, and the second end of the current sensor is connected to the first negative end of the main circuit as the negative electrode of the fifth battery branch.

[0071] The structure and control method of the main circuit relay group and the charging relay group are detailed in the description of the supercharging mode and will not be repeated here.

[0072] If the charging pile is unplugged, the BMS controls each relay to disconnect. The disconnection order of each relay is opposite to the closing order, which will not be repeated here.

[0073] In this embodiment, the BMS is also used to enter the discharge mode after determining that the new energy vehicle is not connected to the charging pile; the BMS is also used to control the closure of the second switching relay group so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and control the closure of the main circuit relay group so that the three battery branches discharge the electrical appliances in the new energy vehicle through the main circuit.

[0074] The discharge mode is similar to the normal charge mode. The difference is that after the BMS controls the main circuit relay group to close, the charging relay group is not closed. At this time, the third battery branch, the fourth battery branch, the fifth battery branch and the main circuit are connected in parallel, and the electrical appliances can be discharged through the battery pack.

[0075] Figure 2 The closing sequence of the relay during the charging and discharging process is shown and will not be repeated here.

[0076] In this embodiment, the BMS is also used to control the closure of the second switching relay group when the new energy vehicle is driving and energy recovery is required, so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and control the closure of the main circuit relay group and the charging relay group, so that the recovered energy can charge the three battery branches through the main circuit.

[0077] The charging mode during energy recovery is similar to the general charging mode. The difference is that after the BMS controls the main circuit relay group to close, the charging relay group is not closed. At this time, the third battery branch, the fourth battery branch, the fifth battery branch and the main circuit are connected in parallel, and the battery pack can be discharged through the recovered energy.

[0078] In other words, it is only possible to enter the supercharging mode according to the identification message after connecting to the charging pile. During the energy recovery process, it will only enter the normal charging mode and will not enter the supercharging mode.

[0079] To summarize, the power supply system for new energy vehicles provided in the embodiment of the present application, if the charging pile supports the supercharging mode (900V), the battery pack is configured as two parallel battery branches connected to the main circuit for charging, each battery branch includes three single-pack batteries, which can achieve high-voltage charging, which not only reduces the charging time but also reduces the use of copper busbar current capacity; if the charging pile supports the normal charging mode (600V), the battery pack is configured as three parallel battery branches connected to the main circuit for charging, each battery branch includes two single-pack batteries, which can achieve low-voltage charging, so that it can adapt to all charging piles for charging without increasing costs.

[0080] If the discharge mode is entered, the battery pack will be configured as three parallel battery branches and connected to the main circuit for discharge. Each battery branch includes two single-pack batteries, which can achieve low-voltage discharge. There is no need to develop high-voltage resistant electrical appliances, which can reduce the cost of new energy vehicles.

[0081] like Figure 3 As shown, it shows a method flow chart of a power supply method for a new energy vehicle provided by an embodiment of the present application, and the power supply method for a new energy vehicle can be applied to a new energy vehicle. The power supply method for a new energy vehicle may include:

[0082] Step 301, after determining that the new energy vehicle is connected to the charging pile, determine the current charging mode according to the highest charging voltage supported by the charging pile.

[0083] BMS detects whether the plug-in signals CC2 and A+ exist at the same time. If the plug-in signals CC2 and A+ exist at the same time, it is determined that the new energy vehicle is connected to the charging pile and enters the charging mode; if the plug-in signals CC2 and A+ do not exist at the same time, it is determined that the new energy vehicle is not connected to the charging pile and enters the discharging mode.

[0084] After the new energy vehicle is connected to the charging pile, the charging pile will send an identification message to the BMS. The BMS determines the highest charging voltage supported by the charging pile based on the identification message, and determines the current charging mode based on the highest charging voltage. Among them, the charging mode includes supercharging mode and general charging mode. The charging voltage of the supercharging mode is higher than the charging voltage of the general charging mode. In this embodiment, the charging voltage of the supercharging mode is about 900V, and the charging voltage of the general charging mode is about 600V.

[0085] Assuming that the identification message indicates that the maximum charging voltage supported by the charging pile is 1000V, the BMS determines that the charging mode is the supercharging mode; if the identification message indicates that the maximum charging voltage supported by the charging pile is 800V, the BMS determines that the charging mode is the normal charging mode.

[0086] Step 302, if the charging mode is the supercharging mode, the first switching relay group is controlled to be closed so that the battery pack is configured as two parallel battery branches connected to the main circuit, and each battery branch includes three single-pack batteries; and the main circuit relay group and the charging relay group are controlled to be closed so that the charging module charges the two battery branches through the main circuit.

[0087] like Figure 1 As shown, after the first switching relay group is closed, the single-pack batteries P1, P2 and P3 form a first battery branch, and the single-pack batteries P4, P5 and P6 form a second battery branch. These two battery branches are connected in parallel to the main circuit, and the charging module charges the two battery branches through the main circuit.

[0088] Step 303, if the charging mode is the general charging mode, the second switching relay group is controlled to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and the main circuit relay group and the charging relay group are controlled to close so that the charging module charges the three battery branches through the main circuit.

[0089] like Figure 1 As shown, after the second switching relay group is closed, the single-pack batteries P1 and P2 form a third battery branch, the single-pack batteries P3 and P4 form a fourth battery branch, and the single-pack batteries P5 and P6 form a fifth battery branch. These three battery branches are connected in parallel to the main circuit, and the charging module charges the three battery branches through the main circuit.

[0090] Optionally, if entering the discharge mode, the BMS controls the second switching relay group to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, each battery branch includes two single-pack batteries; and controls the main circuit relay group to close so that the three battery branches discharge to the electrical appliances in the new energy vehicle through the main circuit.

[0091] Optionally, when a new energy vehicle is driving and energy recovery is required, the BMS controls the second switching relay group to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and controls the main circuit relay group and the charging relay group to close, so that the recovered energy can charge the three battery branches through the main circuit.

[0092] To summarize, the power supply method for new energy vehicles provided in the embodiment of the present application, if the charging pile supports the supercharging mode (900V), the battery pack is configured as two parallel battery branches connected to the main circuit for charging, each battery branch includes three single-pack batteries, which can achieve high-voltage charging, which not only reduces the charging time but also reduces the use of copper busbar current capacity; if the charging pile supports the normal charging mode (600V), the battery pack is configured as three parallel battery branches connected to the main circuit for charging, each battery branch includes two single-pack batteries, which can achieve low-voltage charging, so that it can adapt to all charging piles for charging without increasing costs.

[0093] If the discharge mode is entered, the battery pack will be configured as three parallel battery branches and connected to the main circuit for discharge. Each battery branch includes two single-pack batteries, which can achieve low-voltage discharge. There is no need to develop high-voltage resistant electrical appliances, which can reduce the cost of new energy vehicles.

[0094] An embodiment of the present application provides a computer-readable storage medium, in which at least one instruction is stored. The at least one instruction is loaded and executed by a processor to implement the power supply method for a new energy vehicle as described above.

[0095] An embodiment of the present application provides a new energy vehicle, which includes a power supply system of any of the above-mentioned new energy vehicles.

[0096] It should be noted that: the power supply system for new energy vehicles provided in the above embodiments only uses the division of the above functional modules as an example when supplying power to new energy vehicles. In actual applications, the above functional distribution can be completed by different functional modules as needed, that is, the internal structure of the power supply system for new energy vehicles is divided into different functional modules to complete all or part of the functions described above. In addition, the power supply system for new energy vehicles provided in the above embodiments and the power supply method embodiment for new energy vehicles belong to the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0097] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0098] The above description is not intended to limit the embodiments of the present application. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present application should be included in the protection scope of the embodiments of the present application.

Claims

1. A power supply system for a new energy vehicle, characterized in that: The power supply system includes a battery pack and a power distribution module, wherein the battery pack includes six single-pack batteries, and the power distribution module includes a battery management system BMS and multiple relay groups, wherein the multiple relay groups include a first switching relay group, a second switching relay group, a main circuit relay group and a charging relay group; The BMS is used to determine the current charging mode according to the highest charging voltage supported by the charging pile after determining that the new energy vehicle is connected to the charging pile; If the charging mode is the supercharging mode, the BMS is further used to control the first switching relay group to close, so that the battery pack is configured as two parallel battery branches connected to the main circuit, each battery branch includes three single-pack batteries; and control the main circuit relay group and the charging relay group to close, so that the charging module charges the two battery branches through the main circuit; If the charging mode is the general charging mode, the BMS is also used to control the second switching relay group to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and control the main circuit relay group and the charging relay group to close, so that the charging module charges the three battery branches through the main circuit.

2. The power supply system for new energy vehicles according to claim 1, characterized in that: The BMS is further configured to enter a discharge mode after determining that the new energy vehicle is not connected to the charging pile; The BMS is also used to control the closure of the second switching relay group so that the battery pack is configured as three parallel battery branches connected to the main circuit, each battery branch includes two single-pack batteries; and control the closure of the main circuit relay group so that the three battery branches discharge to the electrical appliances in the new energy vehicle through the main circuit.

3. The power supply system for new energy vehicles according to claim 1, characterized in that: The BMS is also used to control the second switching relay group to close when the new energy vehicle is driving and energy recovery is required, so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and control the main circuit relay group and the charging relay group to close, so that the recovered energy can charge the three battery branches through the main circuit.

4. The power supply system for new energy vehicles according to claim 1, characterized in that: The battery pack includes first to sixth single pack batteries, the first switching relay group includes first to fourth relays, and the first switching relay group is closed; The negative electrode of the first battery pack is connected to the positive electrode of the second battery pack, the negative electrode of the second battery pack is connected to the first end of the first relay, the second end of the first relay is connected to the positive electrode of the third battery pack, the negative electrode of the third battery pack is connected to the first end of the second relay, the second end of the second relay is connected to the first negative end of the main circuit as the negative electrode of the first battery branch, and the positive electrode of the first battery pack is connected to the first positive end of the main circuit as the positive electrode of the first battery branch; The negative electrode of the fourth single-pack battery is connected to the first end of the third relay, the second end of the third relay is connected to the positive electrode of the fifth single-pack battery, the negative electrode of the fifth single-pack battery is connected to the positive electrode of the sixth single-pack battery, the negative electrode of the sixth single-pack battery is connected to the first negative end of the main circuit as the negative electrode of the second battery branch, the positive electrode of the fourth single-pack battery is connected to the first end of the fourth relay, and the second end of the fourth relay is connected to the first positive end of the main circuit as the positive electrode of the second battery branch.

5. The power supply system for new energy vehicles according to any one of claims 1 to 3, characterized in that: The battery pack includes first to sixth single pack batteries, the second switching relay group includes fifth to ninth relays, and the second switching relay group is closed; The negative electrode of the first battery pack is connected to the positive electrode of the second battery pack, the negative electrode of the second battery pack is connected to the first end of the fifth relay, the second end of the fifth relay is connected to the first negative end of the main circuit as the negative electrode of the third battery branch, and the positive electrode of the first battery pack is connected to the first positive end of the main circuit as the positive electrode of the third battery branch; The negative electrode of the third battery pack is connected to the first end of the sixth relay, the second end of the sixth relay is connected to the positive electrode of the fourth battery pack, the negative electrode of the fourth battery pack is connected to the first end of the seventh relay, the second end of the seventh relay is connected to the first negative end of the main circuit as the negative electrode of the fourth battery branch, the positive electrode of the third battery pack is connected to the first end of the eighth relay, and the second end of the eighth relay is connected to the first positive end of the main circuit as the positive electrode of the fourth battery branch; The negative electrode of the fifth single-pack battery is connected to the positive electrode of the sixth single-pack battery, and the negative electrode of the sixth single-pack battery is connected to the first negative terminal of the main circuit as the negative electrode of the fifth battery branch. The positive electrode of the fifth single-pack battery is connected to the first terminal of the ninth relay, and the second terminal of the ninth relay is connected to the first positive terminal of the main circuit as the positive electrode of the fifth battery branch.

6. The power supply system for new energy vehicles according to claim 4 or 5, characterized in that: The main circuit relay group includes a tenth relay and an eleventh relay; The first end of the tenth relay serves as the first negative end of the main circuit, and the second end of the tenth relay serves as the second negative end of the main circuit; The first end of the eleventh relay serves as the first positive end of the main circuit, and the second end of the eleventh relay serves as the second positive end of the main circuit.

7. The power supply system for new energy vehicles according to claim 6, characterized in that: The main circuit relay group also includes a twelfth relay and a pre-charge module; The first end of the twelfth relay is connected to the first end of the eleventh relay and serves as the first positive end of the main circuit; The second end of the twelfth relay is connected to the first end of the pre-charging module; The second end of the pre-charging module is connected to the second end of the eleventh relay and serves as the second positive end of the main circuit.

8. The power supply system for new energy vehicles according to claim 6, characterized in that: The charging relay group includes thirteenth to sixteenth relays; The first ends of the thirteenth relay and the fourteenth relay are respectively connected to the second negative end of the main circuit, and the second ends of the thirteenth relay and the fourteenth relay are respectively connected to the negative electrodes of the two charging modules; The first ends of the fifteenth relay and the sixteenth relay are respectively connected to the second positive end of the main circuit, and the second ends of the fifteenth relay and the sixteenth relay are respectively connected to the positive poles of the two charging modules.

9. A charging method for a new energy vehicle, characterized in that: Used in a power supply system according to any one of claims 1 to 8, the method comprises: After determining that the new energy vehicle is connected to a charging pile, determining the current charging mode according to the highest charging voltage supported by the charging pile; If the charging mode is the supercharging mode, the first switching relay group is controlled to be closed, so that the battery pack is configured as two parallel battery branches connected to the main circuit, each battery branch includes three single-pack batteries; and the main circuit relay group and the charging relay group are controlled to be closed, so that the charging module charges the two battery branches through the main circuit; If the charging mode is the general charging mode, the second switching relay group is controlled to close so that the battery pack is configured as three parallel battery branches connected to the main circuit, and each battery branch includes two single-pack batteries; and the main circuit relay group and the charging relay group are controlled to close so that the charging module charges the three battery branches through the main circuit.

10. A new energy vehicle, characterized in that: The new energy vehicle comprises a power supply system for the new energy vehicle as described in any one of claims 1 to 8.

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