Battery self-heating system, battery self-heating system control method, and electric vehicle

Abstract

A battery self-heating system, a control method for the battery self-heating system, and an electric vehicle, the battery self-heating system including a three-phase motor, a battery pack, a three-phase inverter, and a switch module. The method for controlling the battery self-heating system includes: obtaining battery pack temperature information; when the battery pack temperature information determines that the battery pack requires self-heating, obtaining voltage information between a first end and a second end of a switch module; and controlling the switch module to achieve self-heating of the battery pack in accordance with the voltage information between the first end and the second end of the switch module; when the battery pack temperature information determines that the battery pack does not require self-heating, obtaining current information between the first end and the second end of the switch module; and controlling the switch module to prevent self-heating of the battery pack in accordance with the current information between the first end and the second end of the switch module.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of Chinese Patent Application No. 202211710967.X, entitled "BATTERY SELF-HEATING SYSTEM, CONTROL METHOD THEREFOR, AND ELECTRIC VEHICLE," filed on December 29, 2022, the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a battery self-heating system, a control method for a battery self-heating system, and an electric vehicle. [Background technology]

[0003] To ensure that electric or hybrid electric vehicles can run normally in low-temperature environments, the batteries of electric vehicles usually need to be heated to ensure that the batteries can be charged and discharged normally. However, if the battery's self-heating process is not accurately and effectively controlled, sintering of the switchgear may occur, resulting in the battery being unable to effectively control its self-heating, which will have a significant impact on the operation of the electric vehicle and the user experience. Summary of the Invention

[0004] The present disclosure is intended to solve at least one of the technical problems of the related art to some extent. In this regard, the purpose of the present disclosure is to provide a control method for a battery self-heating system, so that the battery can be accurately controlled to self-heat, so as to ensure that the battery can perform normal self-heating operation and improve the efficiency of charging and discharging the battery.

[0005] A second object of the present disclosure is to provide a battery self-heating system.

[0006] A third object of the present disclosure is to provide an electric vehicle.

[0007] To achieve the above object, one embodiment of a first aspect of the present disclosure provides a control method for a battery self-heating system, the control method including: acquiring temperature information of a battery pack, the battery pack including a first battery body and a second battery body, the first battery body and the second battery body being connected in series and having a first node; a three-phase inverter connected to the battery pack and a three-phase motor, respectively; a first end of a switch module connected to the first node; and a second end of the switch module connected to a neutral point of the three-phase motor; and acquiring voltage information between the first end and the second end of the switch module when it is determined from the temperature information of the battery pack that the battery pack requires self-heating. and controlling the switch module to be closed in response to voltage information between a first end and a second end of the switch module, and controlling the three-phase inverter to allow the first battery body and the second battery body to be alternately charged and discharged, thereby realizing self-heating of the battery pack; and when it is determined from the temperature information of the battery pack that the battery pack does not require self-heating, obtaining current information between the first end and the second end of the switch module; and controlling the switch module to be open in response to the current information between the first end and the second end of the switch module.

[0008] According to the control method of this embodiment, temperature information of the battery pack is first obtained, and then it is determined whether the battery pack needs self-heating based on the temperature information. If the battery pack needs self-heating, the switch module is controlled to be closed according to the voltage between the two ends of the switch module to allow the battery to self-heat. If the battery pack does not need self-heating, the switch module is controlled to be open according to the current between the two ends of the switch module to prevent the battery from self-heating. Therefore, the battery can be accurately controlled to self-heat so as to ensure that the battery can perform normal self-heating operation and improve the efficiency of charging and discharging the battery.

[0009] In some embodiments, the switch module includes a first switch tube, a second switch tube, a first freewheeling diode, a second freewheeling diode, and a first contactor. A first end of the first switch tube is connected to a first node, and a second end of the first switch tube is connected to a second end of the second switch tube. A first end of the second switch tube is connected to one end of the first contactor, and the other end of the first contactor is connected to a neutral point of the three-phase motor. An anode of the first freewheeling diode is connected to the second end of the first switch tube, and a cathode of the first freewheeling diode is connected to the first end of the first switch tube. An anode of the second freewheeling diode is connected to the second end of the second switch tube, and a cathode of the second freewheeling diode is connected to the first end of the second switch tube.

[0010] In some embodiments, the switch module includes a first switch tube, a second switch tube, and a first contactor, wherein a first end of the first switch tube is connected to a second end of the second switch tube and connected to a first node, a second end of the first switch tube is connected to the first end of the second switch tube and connected to one end of the first contactor, and the other end of the first contactor is connected to a neutral point of the three-phase motor.

[0011] In some embodiments, the switch module further includes a first freewheeling diode and a second freewheeling diode, the anode of the first freewheeling diode being connected to the second end of the second switch tube and the cathode of the first freewheeling diode being connected to the first end of the first switch tube, the anode of the second freewheeling diode being connected to the second end of the first switch tube and the cathode of the second freewheeling diode being connected to the first end of the second switch tube.

[0012] In some embodiments, the method further includes controlling the first contactor to be closed after the temperature information of the battery pack determines that the battery pack requires self-heating.

[0013] In some embodiments, the switch module is controlled in response to voltage information between the first end and the second end of the switch module by first controlling the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, then obtaining voltage information between the first end and the second end of the switch module and controlling the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, or When it is determined that the voltage between the first end and the second end of the switch module is equal to or greater than zero, first, the first switch tube is controlled to be closed, and then voltage information between the first end and the second end of the switch module is acquired, and when it is determined that the voltage between the first end and the second end of the switch module is equal to or greater than zero, the second switch tube is controlled to be closed; when it is determined that the first switch tube and the second switch tube are both in a closed state, a target temperature of the battery pack is acquired, and the three-phase inverter is controlled to adjust the amplitude and frequency of a self-heating current of the battery pack according to the target temperature of the battery pack, so that the battery pack is heated to the target temperature.

[0014] In some embodiments, the method further includes setting a target self-heating current for the battery pack to zero after the temperature information of the battery pack determines that the battery pack does not require self-heating.

[0015] In some embodiments, controlling the switch module according to current information between the first end and the second end of the switch module includes first controlling the second switch tube to open when the current information determines that the current between the first end and the second end of the switch module is greater than zero, then obtaining current information between the first end and the second end of the switch module, and controlling the first switch tube to open when the current between the first end and the second end of the switch module is less than a first preset current; When the current information determines that the current between the first end and the second end of the switch module is less than zero, first, the first switch tube is controlled to be open; then, current information between the first end and the second end of the switch module is obtained, and when the current between the first end and the second end of the switch module is determined to be greater than a second preset current, the first switch tube is controlled to be open; and when it is determined that both the first switch tube and the second switch tube are in an open state, the first contactor is controlled to be open.

[0016] In some embodiments, the switch module includes a first switch tube, a second switch tube, a first freewheeling diode, a second freewheeling diode, and a first contactor. A first end of the first switch tube is connected to a first node, and a second end of the first switch tube is connected to a second end of the second switch tube. The first end of the second switch tube is connected to a neutral point of a three-phase motor. An anode of the first freewheeling diode is connected to the second end of the first switch tube, and a cathode of the first freewheeling diode is connected to the first end of the first switch tube. An anode of the second freewheeling diode is connected to the second end of the second switch tube, and a cathode of the second freewheeling diode is connected to the first end of the second switch tube.

[0017] In some embodiments, the switch module includes a first switch tube and a second switch tube, a first end of the first switch tube connected to a second end of the second switch tube and connected to a first node, and a second end of the first switch tube connected to the first end of the second switch tube and connected to a neutral point of a three-phase motor.

[0018] In some embodiments, the switch module further includes a first freewheeling diode and a second freewheeling diode, the anode of the first freewheeling diode being connected to the second end of the second switch tube and the cathode of the first freewheeling diode being connected to the first end of the first switch tube, the anode of the second freewheeling diode being connected to the second end of the first switch tube and the cathode of the second freewheeling diode being connected to the first end of the second switch tube.

[0019] In some embodiments, the switch module is controlled in response to voltage information between the first end and the second end of the switch module by first controlling the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, then obtaining voltage information between the first end and the second end of the switch module and controlling the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, or When it is determined that the voltage between the first end and the second end of the switch module is equal to or greater than zero, first, the first switch tube is controlled to be closed, and then voltage information between the first end and the second end of the switch module is acquired, and when it is determined that the voltage between the first end and the second end of the switch module is equal to or greater than zero, the second switch tube is controlled to be closed; when it is determined that the first switch tube and the second switch tube are both in a closed state, a target temperature of the battery pack is acquired, and the three-phase inverter is controlled to adjust the amplitude and frequency of a self-heating current of the battery pack according to the target temperature of the battery pack, so that the battery pack is heated to the target temperature.

[0020] In some embodiments, the method further includes setting a target self-heating current for the battery pack to zero after the temperature information of the battery pack determines that the battery pack does not require self-heating.

[0021] In some embodiments, the switch module is controlled according to current information between the first end and the second end of the switch module, wherein when the current information determines that the current between the first end and the second end of the switch module is greater than zero, the second switch tube is first controlled to be opened; then, current information between the first end and the second end of the switch module is obtained; and when the current between the first end and the second end of the switch module is determined to be less than a third preset current, the first switch tube is controlled to be opened, thereby controlling the first switch tube and the and allowing both the first switch tube and the second switch tube to be in an open state; and when the current information determines that the current between the first end and the second end of the switch module is less than zero, first controlling the first switch tube to be open; then obtaining current information between the first end and the second end of the switch module, and when it determines that the current between the first end and the second end of the switch module exceeds a fourth preset current, controlling the second switch tube to be open, thereby allowing both the first switch tube and the second switch tube to be in an open state.

[0022] To achieve the above-mentioned object, one embodiment of a second aspect of the present disclosure provides a battery self-heating system. The battery self-heating system includes a three-phase motor, a battery pack, a three-phase inverter, a switch module, and a control component. The battery pack includes a first battery body and a second battery body. The first battery body and the second battery body are connected in series and have a first node. The three-phase inverter is connected to the battery pack and the three-phase motor, respectively. A first end of the switch module is connected to the first node, and a second end of the switch module is connected to a neutral point of the three-phase motor. The control component is connected to the three-phase motor, the battery pack, the three-phase inverter, and the switch module, respectively. The control component is configured to acquire temperature information of the battery pack, and, when the temperature information of the battery pack determines that the battery pack requires self-heating, acquire voltage information between a first end and a second end of the switch module and control the switch module according to the voltage information between the first end and the second end of the switch module to realize self-heating of the battery pack, and, when the temperature information of the battery pack determines that the battery pack does not require self-heating, acquire current information between the first end and the second end of the switch module and control the switch module according to the current information between the first end and the second end of the switch module to prevent self-heating of the battery pack.

[0023] In a battery self-heating system according to an embodiment of the present disclosure, a control component first obtains temperature information of a battery pack, and then determines whether the battery pack requires self-heating based on the temperature information. If the battery pack requires self-heating, the control component controls the switch module to close according to the voltage between the two ends of the switch module, thereby allowing the battery to self-heat. If the battery pack does not require self-heating, the control component controls the switch module to open according to the current between the two ends of the switch module, thereby preventing the battery from self-heating. Therefore, the battery can be accurately controlled to self-heat to ensure that the battery can perform normal self-heating operations and improve the efficiency of battery charging and discharging.

[0024] To achieve the above object, an embodiment of a third aspect of the present disclosure provides an electric vehicle, the electric vehicle including a battery self-heating system according to the above embodiment.

[0025] According to the electric vehicle of this embodiment of the present disclosure, through the self-heating system in the above-mentioned embodiment, the battery can be precisely controlled to self-heat, so as to ensure that the battery can perform normal self-heating operation and to improve the efficiency of charging and discharging the battery.

[0026] Additional aspects and advantages of the disclosure will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the disclosure. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a flowchart of a method for controlling a battery self-heating system according to one embodiment of the present disclosure. [Figure 2A] FIG. 1 is a structural block diagram of a battery self-heating system according to one embodiment of the present disclosure. [Figure 2B]FIG. 1 is a structural block diagram of a battery self-heating system according to one embodiment of the present disclosure. [Figure 3A] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 3B] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 4A] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 4B] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 5A] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 5B] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 6] 10 is a flowchart of a control method for a battery self-heating system according to another embodiment of the present disclosure. [Figure 7] FIG. 2 is a schematic diagram of a carrier period signal according to a specific embodiment of the present disclosure. [Figure 8] 10 is a flowchart of a control method for a battery self-heating system according to another embodiment of the present disclosure. [Figure 9] 10 is a flowchart of a control method for a battery self-heating system according to another embodiment of the present disclosure. [Figure 10] 1 is a flowchart of a method for controlling a battery self-heating system according to a specific embodiment of the present disclosure. [Figure 11] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 12] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 13] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 14] FIG. 10 is a structural block diagram of a battery self-heating system according to another embodiment of the present disclosure. [Figure 15] 10 is a flowchart of a control method for a battery self-heating system according to another embodiment of the present disclosure. [Figure 16] 10 is a flowchart of a control method for a battery self-heating system according to another embodiment of the present disclosure. [Figure 17] 10 is a flowchart of a control method for a battery self-heating system according to another embodiment of the present disclosure. [Figure 18] 10 is a flowchart of a control method for a battery self-heating system according to another specific embodiment of the present disclosure. [Figure 19] FIG. 10 is a structural block diagram of a battery self-heating system according to yet another embodiment of the present disclosure. [Figure 20] FIG. 1 is a structural block diagram of an electric vehicle according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0028]

[0023] The embodiments of the present disclosure are described in detail below. Examples of the embodiments are illustrated in the accompanying drawings, and the same or similar reference numerals in all the accompanying drawings indicate the same or similar components, or components having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present disclosure, and cannot be construed as limiting the present disclosure.

[0029] A battery self-heating system, a control method for a battery self-heating system, and an electric vehicle according to embodiments of the present disclosure will be described below with reference to the accompanying drawings.

[0030] FIG. 1 is a flowchart of a method for controlling a battery self-heating system according to one embodiment of the present disclosure.

[0031] The present disclosure provides a control method based on the above-mentioned battery self-heating system, as shown in Figure 1. The control method includes the following steps:

[0032] In S10, temperature information of a battery pack is acquired. The battery pack includes a first battery body and a second battery body. The first battery body and the second battery body are connected in series and have a first node. A three-phase inverter is connected to the battery pack and a three-phase motor, respectively. A first end of a switch module is connected to the first node, and a second end of the switch module is connected to a neutral point of the three-phase motor.

[0033] First, referring to FIG. 2A, it should be noted that the battery self-heating system 1 includes a three-phase motor 10, a battery pack 20, a three-phase inverter 30, and a switch module 40.

[0034] The input terminal of the three-phase inverter 30 is connected to the battery pack 20. The upper and lower bridge arm connection points of the three phase bridge arms of the three-phase inverter 30 are respectively connected to the three input terminals of the three-phase motor 10. The three-phase inverter 30 may invert the DC provided by the battery pack 20 and supply the AC obtained through the inversion to the motor 10 so that the motor 10 can operate normally. The battery self-heating system 1 further includes a DC charging / discharging port. The DC charging / discharging port may be connected to an external power source to charge the battery pack 20, or alternatively, may be connected to an external electrical appliance so that the battery pack 20 can supply power to the external electrical appliance. In this embodiment, the battery pack 20 includes a first battery body E1 and a second battery body E2. The first battery body E1 and the second battery body E2 are connected in series and have a first node P. The switch module 40 is disposed between the first node P and the neutral point N of the three-phase motor 10. The battery pack 20 can be controlled to perform self-heating by controlling the closed / open state of the switch module 40. Specifically, the switch module 40 includes a plurality of switch devices. By controlling the closed / open state of the switch devices in the switch module 40, the battery is precisely controlled to perform self-heating to ensure that the battery can perform normal self-heating operation and to improve the efficiency of charging and discharging the battery.

[0035] 2A, the battery self-heating system 1 further includes a contactor disposed between the battery pack 20 and the three-phase inverter 30. Therefore, whether the battery pack 20 is connected to the three-phase inverter 30 can be controlled by controlling the contactor. A contactor is also disposed between the neutral point N of the motor 10 and the DC charging / discharging port. It may be understood that the contactor may alternatively be configured to control the connection relationship between the modules. The battery self-heating system 1 further includes a first capacitor C1 and a second capacitor C2, which can filter the voltage. The three-phase inverter 30 may include three phase bridge arms. Each phase bridge arm includes an upper bridge arm and a lower bridge arm formed by a switch tube, and each switch tube of the three phase bridge arms further includes a freewheeling diode. Specifically, the first phase bridge arm includes an upper bridge arm VT1 and a lower bridge arm VT2. The second phase bridge arms include upper bridge arm VT3 and lower bridge arm VT4, and the third phase bridge arms include upper bridge arm VT5 and lower bridge arm VT6.A freewheeling diode is provided corresponding to each switch tube, i.e., a freewheeling diode VD1 is provided corresponding to the upper bridge arm VT1 of the first phase bridge arm, a freewheeling diode VD2 is provided corresponding to the lower bridge arm VT2 of the first phase bridge arm, a freewheeling diode VD3 is provided corresponding to the upper bridge arm VT3 of the second phase bridge arm, a freewheeling diode VD4 is provided corresponding to the lower bridge arm VT4 of the second phase bridge arm, a freewheeling diode VD5 is provided corresponding to the upper bridge arm VT5 of the third phase bridge arm, and a freewheeling diode VD6 is provided corresponding to the lower bridge arm VT6 of the third phase bridge arm.

[0036] In S20, if the temperature information of the battery pack determines that the battery pack requires self-heating, voltage information between the first end and the second end of the switch module is obtained.

[0037] In S30, the switch module is controlled to be closed according to the voltage information between the first end and the second end of the switch module, and the three-phase inverter is controlled to allow the first battery body and the second battery body to be alternately charged and discharged, thereby realizing self-heating of the battery pack.

[0038] In S40, if the temperature information of the battery pack determines that the battery pack does not require self-heating, current information between the first end and the second end of the switch module is obtained.

[0039] In S50, the switch module is controlled to open in response to the current information between the first end and the second end of the switch module.

[0040] Specifically, referring to FIGS. 1 and 2A , when the temperature of the environment in which the electric vehicle is located is relatively low, the operating temperature of the battery pack 20 may be affected, which may affect the efficiency of charging and discharging the battery pack 20. In this embodiment, when the temperature of the battery pack 20 is relatively low, the battery pack 20 may be self-heated to improve the efficiency of charging and discharging the battery pack 20. First, temperature information of the battery pack 20 may be obtained, and it may be determined whether the battery pack 20 requires heating based on the temperature information of the battery pack 20. Specifically, the temperature of the battery pack 20 may be determined according to the temperature information of the battery pack 20, and then the temperature of the battery pack 20 may be compared with a preset temperature. When the temperature of the battery pack 20 is lower than the preset temperature, it may be determined that the battery pack does not require heating. When the temperature of the battery pack 20 is higher than the preset temperature, it may be determined that the battery pack does not require heating. The preset temperature may be determined according to information such as specification parameters of the battery pack 20, or may be set at the time of shipment. For example, the preset temperature may be 3° C., 4° C., or 5° C. Of course, the preset temperature may alternatively be a temperature range, such as -3° C. to 3° C.

[0041] In this embodiment, temperature information of the battery pack 20 may be obtained through a device such as a temperature sensor. After the temperature information of the battery pack 20 is obtained, if it is determined that the battery pack 20 requires heating, voltage information between the first end and the second end of the switch module may be further obtained, and then the switch device of the switch module may be controlled to close according to the voltage information to prevent arcing in the closing process, which may cause problems such as sintering. However, if it is determined that the battery pack 20 does not require heating, current information between the first end and the second end of the switch module may be further obtained, and then the switch device of the switch module may be controlled to open according to the current information to prevent arcing in the switch device during the opening process, which may cause problems such as sintering.

[0042] In some embodiments, as shown in FIG. 2A , the switch module 40 includes a first switch tube VT7, a second switch tube VT8, and a first contactor K1. The first switch tube VT7 is associated with a first freewheeling diode VD7. The second switch tube VT8 is associated with a second freewheeling diode VD8. A first end of the first switch tube VT7 is connected to a first node P, and a second end of the first switch tube VT7 is connected to a second end of the second switch tube VT8. A first end of the second switch tube VT8 is connected to one end of the first contactor K1, and the other end of the first contactor K1 is connected to a neutral point N of the three-phase motor. The anode of the first freewheeling diode VD7 is connected to the second end of the first switch tube VT7, and the cathode of the first freewheeling diode VD7 is connected to the first end of the first switch tube VT7. The anode of the second freewheeling diode VD8 is connected to the second end of the second switch tube VT8, and the cathode of the second freewheeling diode VD8 is connected to the first end of the second switch tube VT8.

[0043] Specifically, in this embodiment, both the first switch tube VT7 and the second switch tube VT8 are provided with corresponding freewheeling diodes, so that current can flow forward through the switch module 40 and reversely through the switch module 40, thereby providing current to the first battery body E1 of the battery pack 20 for self-heating and providing current to the second battery body E2 of the battery pack 20 for self-heating, which can be seen by referring to FIG. 2A .

[0044] Optionally, in some embodiments, referring to FIG. 2B, a second contactor K2 may be added based on the original FIG. 2A, and one end of the second contactor K2 is connected to the first node P, and the other end of the second contactor K2 is connected to the first end of the first switch tube VT7.

[0045] 3A, the switch module 40 includes a first switch tube VT7, a second switch tube VT8, and a first contactor K1. A first end of the first switch tube VT7 is connected to a second end of the second switch tube VT8 and connected to a first node P, and a second end of the first switch tube VT7 is connected to a first end of the second switch tube VT8 and connected to one end of the first contactor K1, the other end of which is connected to a neutral point N of the three-phase motor.

[0046] Optionally, in some embodiments, referring to Figure 3B, a second contactor K2 may be added based on the original Figure 3A. One end of the second contactor K2 is connected to the first node P, and a first end of the first switch tube VT7 is connected to a second end of the second switch tube VT8 and to the other end of the second contactor K2.

[0047] Specifically, in this embodiment, the first switch tube VT7 and the second switch tube VT8 are connected in parallel in opposite directions to form a branch, and the parallel branch is connected in series to the first contactor K1. The first switch tube VT7 and the second switch tube VT8 are connected in parallel in opposite directions, so that current can flow forward through the switch module 40 to heat one battery body of the battery pack 20, and flow backward through the switch module 40 to heat the other battery body of the battery pack 20, thereby ensuring that the battery pack 20 can be normally self-heated.

[0048] 4A or 5A, the switch module 40 in this embodiment further includes a first freewheeling diode VD7 and a second freewheeling diode VD8. The anode of the first freewheeling diode VD7 is connected to the second end of the second switch tube VT8, and the cathode of the first freewheeling diode VD7 is connected to the first end of the first switch tube VT7. The anode of the second freewheeling diode VD8 is connected to the second end of the first switch tube VT7, and the cathode of the second freewheeling diode VD8 is connected to the first end of the second switch tube VT8.

[0049] 4A or 5A, it can be seen that the switch module 40 in this embodiment may further include a first freewheeling diode VT7 and a second freewheeling diode VT8. More specifically, the first freewheeling diode VD7 and the second freewheeling diode VD8 are respectively arranged in two switch tubes connected in parallel in opposite directions and arranged in reverse, so as to further restrict the current passing through the switch module 40 to flow in only one direction at a time but not in the other direction, thereby ensuring that the first battery body E1 and the second battery body E2 of the battery pack 20 can be alternately self-heated.

[0050] Optionally, in some embodiments, a second contactor may be added based on the original FIG. 4A or FIG. 5A with reference to FIG. 4B or FIG. 5B. As shown in FIG. 4B, one end of the second contactor K2 is connected to the first node P, and the other end of the second contactor K2 is connected to the first end of the first switch tube VT7. Furthermore, as shown in FIG. 5B, one end of the second contactor K2 is connected to the first node P, and the other end of the second contactor K2 is connected to the second end of the second switch tube VT8.

[0051] For the specific battery self-heating system 1 shown in FIG. 2A, 3A, 4A, or 5A, this embodiment provides a corresponding specific control method to control the open / close states of various devices in the switch module 40 to complete the self-heating control of the battery pack 20, thereby avoiding the problem of sintering caused by arcing during the closing or opening of various devices in the switch module 40. Specifically, when the temperature information of the battery pack 20 determines that the battery pack 20 requires self-heating, if there is a contactor connected in series in the switch device branch, the contactor is first closed, and then the switch device is closed, thereby preventing the contactor from sintering. The control method of the battery self-heating system 1 in this embodiment will be specifically described below. In this embodiment, the branch corresponding to the switch module includes a first contactor K1 connected in series.

[0052] In this embodiment, after it is determined from the temperature information of the battery pack 20 that the battery pack 20 requires self-heating, the first contactor K1 is controlled to be closed.

[0053] Specifically, the first contactor K1 in this embodiment is connected in series with the branch corresponding to the switch tube. When the battery pack 20 needs self-heating to prevent the contactor from sintering, the first contactor K1 may be controlled to be closed first, and then, if the switch device is not yet controlled to be closed, the switch device of the switch module 40 is controlled to be closed according to the voltage information between the first end and the second end of the switch module 40.

[0054] In some embodiments, as shown in FIG. 6, controlling the switch module in response to the voltage information between the first end and the second end of the switch module includes the following steps:

[0055] In S601, if the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, the second switch tube is first controlled to be closed; then voltage information between the first end and the second end of the switch module is obtained, and if the voltage between the first end and the second end of the switch module is determined to be less than or equal to zero, the first switch tube is controlled to be closed; or if the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, the first switch tube is first controlled to be closed; then voltage information between the first end and the second end of the switch module is obtained, and if the voltage between the first end and the second end of the switch module is determined to be greater than or equal to zero, the second switch tube is controlled to be closed.

[0056] In S602, when it is determined that both the first switch tube and the second switch tube are in a closed state, the target temperature of the battery pack is obtained.

[0057] In S603, the three-phase inverter is controlled to adjust the amplitude and frequency of the self-heating current of the battery pack according to the target temperature of the battery pack, so that the battery pack is heated to the target temperature.

[0058] Specifically, the description will be provided with reference to FIG. 2A, FIG. 3A, FIG. 4A, or FIG. 5A. After it is determined that the battery pack 20 requires heating and voltage information between the first and second ends of the switch module is obtained, the voltage between the first and second ends of the switch module may be determined according to the voltage information. If the voltage between the first and second ends of the switch module exceeds zero, this indicates that current in the switch module 40 can flow from the first end to the second end, for example, from the first node P to the neutral point of the three-phase motor 10. The second switch tube VT8, which flows in the opposite direction to the current, may be closed to prevent an arc from being generated. If the first switch tube VT7, which flows in the same direction as the current, is controlled to close at this time, an arc may be generated, potentially affecting the safety of the switch module 40. After the second switch tube VT8 is closed, the voltage information between the first and second ends of the switch module is continuously acquired. If the voltage between the first and second ends of the switch module is equal to or less than zero, the first switch tube VT7 can be controlled to close to avoid arc generation. As shown in FIG. 7, the first switch tube VT7 and the second switch tube VT8 in this embodiment can be closed within a control period (i.e., a carrier period), which can reduce electrical stress during closing to ensure that impulse voltages and currents are not generated during the closing process of the switch devices and that the switch module 40 is not damaged.

[0059] When the first switch tube VT7 and the second switch tube VT8 are both in a closed state, a specific self-heating control may be performed on the battery pack 20. First, a target temperature of the battery pack 20, i.e., the temperature at which the battery pack 20 needs to be heated, may be obtained, and then the switch tube of the three-phase inverter 30 is controlled to adjust the amplitude and frequency of the self-heating current of the battery pack 20 according to the target temperature, so that the battery pack 20 can be controlled to self-heat to the corresponding target temperature, thereby completing the self-heating of the battery pack 20.

[0060] In this embodiment, as shown in FIG. 8, the control method for the battery self-heating system further includes the following steps:

[0061] In S801, after it is determined that the battery pack does not require self-heating based on the temperature information of the battery pack, the target self-heating current of the battery pack is set to zero.

[0062] Specifically, when the battery pack has completed heating, i.e., after the temperature information of the battery pack has determined that the battery pack does not require self-heating, the target heating current of the battery pack may be set to zero, and the switch device and contactor of the switch module are opened. If the self-heating current is high and the switch tube is suddenly opened, an arc may be generated and damage the heating module. Therefore, in this embodiment, after the target self-heating current of the battery pack is set to zero, the first switch tube and the second switch tube of the switch module are controlled to open according to the current information between the first end and the second end of the switch module, thereby preventing the battery pack from self-heating.

[0063] Specifically, as shown in FIG. 9, the switch module being controlled according to the current information between the first end and the second end of the switch module includes the following steps:

[0064] In S901, if the current information determines that the current between the first end and the second end of the switch module is greater than zero, the second switch tube is controlled to be opened; then, the current information between the first end and the second end of the switch module is obtained, and if the current between the first end and the second end of the switch module is determined to be less than a first preset current, the first switch tube is controlled to be opened.

[0065] In S902, if the current information determines that the current between the first end and the second end of the switch module is less than zero, the first switch tube is controlled to be opened; then, current information between the first end and the second end of the switch module is obtained, and if the current between the first end and the second end of the switch module is determined to be greater than a second preset current, the first switch tube is controlled to be opened.

[0066] In S903, if it is determined that both the first switch tube and the second switch tube are in an open state, the second contactor is controlled to be opened.

[0067] Specifically, a description is provided with reference to FIG. 2A, FIG. 3A, FIG. 4A, or FIG. 5A. If it is determined that the current between the first end and the second end of the switch module exceeds zero, this indicates that the current of the switch module is currently flowing mainly through the first switch tube VT7, and therefore, the second switch tube VT8 may be controlled to open first. If the first switch tube VT7 is controlled to close first, an arc may be generated, possibly causing a sintering problem. After the second switch tube VT8 is opened, current information between the first end and the second end of the switch module continues to be acquired. If it is determined that the current between the first end and the second end of the switch module is less than a first preset current, the first switch tube VT7 is controlled to open. The first preset current may be specifically limited according to the specification parameters of the battery pack, for example, 5 amperes positive or negative. As long as the current between the first end and the second end of the switch module is determined to be close to zero, the first switch tube VT7 may be controlled to open to avoid the creation of an arc, ensuring that impulse voltages and currents cannot be generated and the switch module 40 cannot be damaged in the process of opening the switch device and contactor.

[0068] If the current between the first and second ends of the switch module is determined to be less than zero, this indicates that the current is currently flowing primarily through the second switch tube VT8, and therefore the first switch tube VT7 may be controlled to open first. If the second switch tube VT8 is controlled to close first, an arc may be generated, potentially causing a sintering problem. After the first switch tube VT7 is opened, current information between the first and second ends of the switch module is continuously acquired. If the current between the first and second ends of the switch module is determined to exceed the second preset current, the second switch tube VT8 is controlled to open. For a description of the second preset current, please refer to the above description of the first preset current. Details will not be described again in this specification. To the extent that the current between the first end and the second end of the switch module is determined to be close to zero, the second switch tube VT8 may be controlled to open to avoid the creation of an arc, ensuring that impulse voltages and currents cannot be generated during the opening of the switch device and contactor and that the switch module 40 cannot be damaged.

[0069] If it is determined that the first switch tube VT7 and the second switch tube VT8 are both in an open state, the first contactor K1 may be further controlled to be open to prevent the battery pack from self-heating.

[0070] In a specific example, as shown in FIG. 10 , after the electric vehicle enters the battery pack self-heating program, the temperature of the battery pack is first acquired to determine whether the battery pack requires self-heating. If it is determined that the battery pack requires self-heating, the first contactor K1 of the switch module is closed, and then it is determined whether the voltage between the first end and the second end of the switch module exceeds zero. If it is determined that the voltage between the first end and the second end of the switch module exceeds zero, the second switch tube VT8 is controlled to be closed. If it is determined that the voltage between the first end and the second end of the switch module does not exceed zero, the first switch tube VT7 is controlled to be closed, and it is determined whether the first switch tube VT7 and the second switch tube VT8 are both in a closed state. If it is determined that neither the first switch tube VT7 nor the second switch tube VT8 are in a closed state, the voltage between the first end and the second end of the switch module is acquired again. If it is determined that the first switch tube VT7 and the second switch tube VT8 are both in a closed state, the self-heating current value of the battery pack is adjusted according to the self-heating requirement of the battery pack to perform self-heating in the battery pack. Then, the temperature of the battery pack is acquired again and determined. If it is determined that the battery pack does not require self-heating, the self-heating target value of the battery pack is adjusted to zero, and then it is determined whether the current between the first end and the second end of the switch module exceeds zero. If it is determined that the current between the first end and the second end of the switch module exceeds zero, the second switch tube VT8 is controlled to be open. If it is determined that the current between the first end and the second end of the switch module does not exceed zero, the first switch tube VT7 is opened, and then it is determined whether the first switch tube VT7 and the second switch tube VT8 are both in an open state.If it is determined that neither the first switch tube VT7 nor the second switch tube VT8 is in an open state, the current between the first end and the second end of the switch module is again acquired. If it is determined that neither the first switch tube VT7 nor the second switch tube VT8 is in an open state, the first contactor K1 is controlled to open, and the battery self-heating program is then terminated.

[0071] 11, the switch module 40 includes a first switch tube VT7, a second switch tube VT8, a first freewheeling diode VD7, and a second freewheeling diode VD8. A first end of the first switch tube VT7 is connected to a first node P, and a second end of the first switch tube VT7 is connected to a second end of the second switch tube VT8. A first end of the second switch tube VT8 is connected to a neutral point N of the three-phase motor. An anode of the first freewheeling diode VD7 is connected to the second end of the first switch tube VT7, and a cathode of the first freewheeling diode VD7 is connected to the first end of the first switch tube VT7. The anode of the second freewheeling diode VD8 is connected to the second end of the second switch tube VT8, and the cathode of the second freewheeling diode VD8 is connected to the first end of the second switch tube VT8.

[0072] Specifically, in this embodiment, both the first switch tube VT7 and the second switch tube VT8 are provided with corresponding freewheeling diodes, so that current can flow forward through the switch module 40 and reversely through the switch module 40, thereby providing current to the first battery body E1 of the battery pack 20 for self-heating and providing current to the second battery body E2 of the battery pack 20 for self-heating, which can be seen by referring to FIG. 11 .

[0073] 12, the switch module 40 includes a first switch tube VT7 and a second switch tube VT8. A first end of the first switch tube VT7 is connected to a second end of the second switch tube VT8 and connected to a first node P, and a second end of the first switch tube VT7 is connected to a first end of the second switch tube VT8 and connected to a neutral point N of the three-phase motor.

[0074] Specifically, in this embodiment, the first switch tube VT7 and the second switch tube VT8 are connected in parallel in reverse direction, so that current can flow in a forward direction through the switch module 40 to heat one battery body of the battery pack 20, and flow in a reverse direction through the switch module 40 to heat the other battery body of the battery pack 20, thereby ensuring that the battery pack 20 can be normally self-heated.

[0075] 13 or 14, it can be seen that the switch module 40 in this embodiment further includes a first freewheeling diode VD7 and a second freewheeling diode VD8. The anode of the first freewheeling diode VD7 is connected to the second end of the second switch tube VD8, and the cathode of the first freewheeling diode VD7 is connected to the first end of the first switch tube VT7. The anode of the second freewheeling diode VD8 is connected to the second end of the first switch tube VT7, and the cathode of the second freewheeling diode VD8 is connected to the first end of the second switch tube VT8.

[0076] 13 or 14, it can be seen that the switch module 40 in this embodiment may further include a first freewheeling diode VT7 and a second freewheeling diode VT8. More specifically, the first freewheeling diode VD7 and the second freewheeling diode VD8 are respectively arranged in two switch tubes connected in parallel in opposite directions and arranged in reverse, so as to further restrict the current passing through the switch module 40 to flow in only one direction at a time but not in the other direction, thereby ensuring that the first battery body E1 and the second battery body E2 of the battery pack 20 can be alternately self-heated.

[0077] 11 to 14, this embodiment provides a corresponding specific control method to control the open / close states of various devices of the switch module 40 to complete the self-heating control of the battery pack 20, thereby avoiding the sintering problem caused by arcing during the closing or opening of various devices of the switch module 40. Specifically, the control method of the battery self-heating system 1 in this embodiment will be specifically described below.

[0078] In some embodiments, as shown in FIG. 15, controlling the switch module in response to the voltage information between the first end and the second end of the switch module includes the following steps:

[0079] In S1501, if the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, the second switch tube is first controlled to be closed; then voltage information between the first end and the second end of the switch module is obtained, and if the voltage between the first end and the second end of the switch module is determined to be less than zero, the first switch tube is controlled to be closed; or if the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, the first switch tube is first controlled to be closed; then voltage information between the first end and the second end of the switch module is obtained, and if the voltage between the first end and the second end of the switch module is determined to be greater than or equal to zero, the second switch tube is controlled to be closed.

[0080] In S1502, if it is determined that both the first switch tube and the second switch tube are in a closed state, the target temperature of the battery pack is obtained.

[0081] In S1503, the three-phase inverter is controlled to adjust the amplitude and frequency of the self-heating current of the battery pack according to the target temperature of the battery pack, and the battery pack is heated to the target temperature.

[0082] Specifically, a description will be provided with reference to FIGS. 11 to 14. After it is determined that the battery pack 20 requires heating and voltage information between the first and second ends of the switch module is obtained, the voltage between the first and second ends of the switch module may be determined according to the voltage information. If the voltage between the first and second ends of the switch module exceeds zero, this indicates that current in the switch module 40 flows from the first end to the second end, i.e., current flows from the first node P to the neutral point of the three-phase motor 10. The second switch tube VT8, which flows in the opposite direction to the current, may be controlled to close to prevent an arc from being generated. If the first switch tube VT7, which flows in the same direction as the current, is controlled to close at this time, an arc may be generated, potentially affecting the safety of the switch module 40. After the second switch tube VT8 is closed, the voltage information between the first and second ends of the switch module is continuously acquired, and if the voltage between the first and second ends of the switch module is equal to or less than zero, the first switch tube VT7 can be controlled to close to avoid arc generation. As shown in Figure 7, the first switch tube VT7 and the second switch tube VT8 in this embodiment can be closed within a control period (i.e., a carrier period), which can reduce electrical stress during closing to ensure that impulse voltages and currents are not generated during the closing process of the switch device and contactor, and that the switch module 40 cannot be damaged.

[0083] When the first switch tube VT7 and the second switch tube VT8 are both in a closed state, a specific self-heating control may be performed on the battery pack 20. First, a target temperature of the battery pack 20, i.e., the temperature at which the battery pack 20 needs to be heated, may be obtained, and then the switch tube of the three-phase inverter 30 is controlled to adjust the amplitude and frequency of the self-heating current of the battery pack 20 according to the target temperature, so that the battery pack 20 can be controlled to self-heat to the corresponding target temperature, thereby completing the self-heating of the battery pack 20.

[0084] In this embodiment, as shown in FIG. 16, the control method for the battery self-heating system further includes the following steps:

[0085] In S1601, after it is determined based on the temperature information of the battery pack that the battery pack does not require self-heating, the target self-heating current of the battery pack is set to zero.

[0086] Specifically, when the battery pack has completed heating, i.e., after the temperature information of the battery pack has determined that the battery pack does not require self-heating, the target heating current of the battery pack may be set to zero, and the switch tube of the switch module is opened. During the self-heating process of the battery pack, the first switch tube and the second switch tube are both in a closed state. However, if the first contactor is directly opened, an arc may be generated, causing sintering. Therefore, in this embodiment, after the target self-heating current of the battery pack is set to zero, the first switch tube and the second switch tube of the switch module can be controlled to open according to the current information between the first end and the second end of the switch module, thereby preventing sintering during the self-heating process of the battery pack.

[0087] Specifically, as shown in FIG. 17, the switch module being controlled according to the current information between the first end and the second end of the switch module includes the following steps:

[0088] In S1701, when the current information determines that the current between the first end and the second end of the switch module is greater than zero, the second switch tube is first controlled to be opened; then, the current information between the first end and the second end of the switch module is obtained; when the current between the first end and the second end of the switch module is determined to be less than a third preset current, the first switch tube is controlled to be opened, allowing both the first switch tube and the second switch tube to be in an open state.

[0089] In S1702, if the current information determines that the current between the first end and the second end of the switch module is less than zero, first, the first switch tube is controlled to be opened; then, current information between the first end and the second end of the switch module is obtained; if the current between the first end and the second end of the switch module is determined to be greater than a fourth preset current, the second switch tube is controlled to be opened, allowing both the first switch tube and the second switch tube to be in an open state.

[0090] Specifically, a description is provided with reference to FIGS. 11 to 14. If it is determined that the current between the first end and the second end of the switch module exceeds zero, this indicates that the current of the switch module is currently flowing primarily through the first switch tube VT7, and therefore, the second switch tube VT8 may be controlled to open first. If the first switch tube VT7 is controlled to close first, an arc may be generated, possibly causing a sintering problem. After the second switch tube VT8 is opened, current information between the first end and the second end of the switch module continues to be acquired. If it is determined that the current between the first end and the second end of the switch module is less than a third preset current, the first switch tube VT7 is controlled to open. The third preset current may be specifically limited according to the specification parameters of the battery pack, for example, 5 amperes positive or negative. As long as the current between the first end and the second end of the switch module is determined to be close to zero, the first switch tube VT7 may be controlled to open to avoid the creation of an arc, ensuring that impulse voltages and currents cannot be generated and the switch module 40 cannot be damaged in the process of opening the switch device and contactor.

[0091] If the current between the first and second ends of the switch module is determined to be less than zero, this indicates that the current is currently flowing primarily through the second switch tube VT8, and therefore the first switch tube VT7 may be controlled to open first. If the second switch tube VT8 is controlled to close first, an arc may be generated, potentially causing a sintering problem. After the first switch tube VT7 is opened, current information between the first and second ends of the switch module is continuously acquired. If the current between the first and second ends of the switch module is determined to exceed a fourth preset current, the second switch tube VT8 is controlled to open. For a description of the fourth preset current, please refer to the above description of the first preset current. Details will not be repeated herein. To the extent that the current between the first and second ends of the switch module is determined to be close to zero, the second switch tube VT8 may be controlled to open to avoid the creation of an arc, ensuring that impulse voltages and currents cannot be generated during the opening of the switch devices and contactors and that the switch module 40 cannot be damaged. If the first switch tube VT7 and the second switch tube VT8 are both determined to be in an open state, the battery pack may be prevented from self-heating.

[0092] In a specific example, as shown in FIG. 18, after the electric vehicle first enters the battery pack self-heating program, the temperature of the battery pack is obtained to determine whether the battery pack requires self-heating. If the battery pack requires self-heating, it is determined whether the voltage between the first end and the second end of the switch module exceeds zero. If it is determined that the voltage between the first end and the second end of the switch module exceeds zero, the second switch tube VT8 is controlled to be closed. If it is determined that the voltage between the first end and the second end of the switch module does not exceed zero, the first switch tube VT7 is controlled to be closed, and then it is determined whether the first switch tube VT7 and the second switch tube VT8 are both in a closed state. If it is determined that neither the first switch tube VT7 nor the second switch tube VT8 are in a closed state, the voltage between the first end and the second end of the switch module continues to be determined. If it is determined that the first switch tube VT7 and the second switch tube VT8 are both in a closed state, the self-heating current value of the battery pack is adjusted according to the self-heating requirement of the battery pack to perform self-heating in the battery pack. Then, the temperature of the battery pack is acquired again and determined. If it is determined that the battery pack does not require self-heating, the self-heating target value of the battery pack is adjusted to zero, and then it is determined whether the current between the first end and the second end of the switch module exceeds zero. If it is determined that the current between the first end and the second end of the switch module exceeds zero, the second switch tube VT8 is controlled to be open. If it is determined that the current between the first end and the second end of the switch module does not exceed zero, the first switch tube VT7 is opened, and then it is determined whether the first switch tube VT7 and the second switch tube VT8 are both in an open state. If it is determined that neither the first switch tube VT7 nor the second switch tube VT8 is in an open state, the current between the first end and the second end of the switch module continues to be determined.If it is determined that the first switch tube VT7 and the second switch tube VT8 are both in an open state, it indicates that the battery is prevented from self-heating, and therefore the battery self-heating program may be terminated.

[0093] It should be noted that in the above-mentioned embodiment, the contactor can complete the closing and opening operations in a manner that a magnetic field is generated by a current flowing through the coil to attract the core. In addition, in the above-mentioned embodiment, the switch tube may be a general thyristor, a turn-off thyristor, a bidirectional thyristor, a metal oxide semiconductor (CMOS) tube, an insulated gate bipolar transistor (IGBT) electric device, a silicon carbide (SiC) tube, etc. In this embodiment, the first end of the switch tube may represent the collector of the transistor, and the second end of the switch tube may represent the transmitter of the transistor.

[0094] In conclusion, in the embodiments of the present disclosure, the switch devices and contactors of the switch module are opened and closed quickly and do not generate impulse voltages and impulse currents, so as to reduce electrical stress when the switch module is closed or opened, achieve the best closing or opening effect, reduce the possibility of damage to the device, and maximize the service life of the electrical equipment.

[0095] FIG. 19 is a structural block diagram of a battery self-heating system according to yet another embodiment of the present disclosure.

[0096] Furthermore, as shown in FIG. 19, the present disclosure provides a battery self-heating system 1. The battery self-heating system 1 includes a three-phase motor 10, a battery pack 20, a three-phase inverter 30, a switch module 40, and a control component 50. Specifically, referring to FIG. 2A, the switch module 40 includes a plurality of switch tubes and a contactor. The contactor is connected in series to the plurality of switch tubes. The battery pack 20 includes a first battery body E1 and a second battery body E2. The first battery body E1 and the second battery body E2 are connected in series and have a first node P. The three-phase inverter 30 is connected to the battery pack 20 and the three-phase motor 10, respectively. A first end of the switch module 40 is connected to the first node P. A second end of the switch module 40 is connected to a neutral point N of the three-phase motor. The control component 50 is connected to the three-phase motor 10, the battery pack 20, the three-phase inverter 30, and the switch module 40. The control component 50 is configured to acquire temperature information of the battery pack 20, and, when the temperature information of the battery pack 20 determines that the battery pack 20 requires self-heating, acquire voltage information between a first end and a second end of the switch module 40 and control the switch module according to the voltage information between the first end and the second end of the switch module 40 to realize self-heating of the battery pack, and, when the temperature information of the battery pack determines that the battery pack does not require self-heating, acquire current information between the first end and the second end of the switch module and control the switch module according to the current information between the first end and the second end of the switch module to prevent self-heating of the battery pack.

[0097] In some embodiments, the switch module includes a first switch tube, a second switch tube, a first freewheeling diode, a second freewheeling diode, and a first contactor. A first end of the first switch tube is connected to a first node, and a second end of the first switch tube is connected to a second end of the second switch tube. A first end of the second switch tube is connected to one end of the first contactor, and the other end of the first contactor is connected to a neutral point of the three-phase motor. An anode of the first freewheeling diode is connected to the second end of the first switch tube, and a cathode of the first freewheeling diode is connected to the first end of the first switch tube. An anode of the second freewheeling diode is connected to the second end of the second switch tube, and a cathode of the second freewheeling diode is connected to the first end of the second switch tube.

[0098] In some embodiments, the switch module includes a first switch tube, a second switch tube, and a first contactor, wherein a first end of the first switch tube is connected to a second end of the second switch tube and connected to a first node, a second end of the first switch tube is connected to the first end of the second switch tube and connected to one end of the first contactor, and the other end of the first contactor is connected to a neutral point of the three-phase motor.

[0099] In some embodiments, the switch module further includes a first freewheeling diode and a second freewheeling diode, wherein the anode of the first freewheeling diode is connected to the second end of the second switch tube and the cathode of the first freewheeling diode is connected to the first end of the first switch tube, and the anode of the second freewheeling diode is connected to the second end of the first switch tube and the cathode of the second freewheeling diode is connected to the first end of the second switch tube.

[0100] In some embodiments, the control component is further configured to control the first contactor to be closed after the temperature information of the battery pack determines that the battery pack requires self-heating.

[0101] In some embodiments, the control component is configured to first control the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, and then obtain voltage information between the first end and the second end of the switch module and control the first switch tube to be closed when the voltage between the first end and the second end of the switch module is determined to be equal to or less than zero, or to first control the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, and then The control circuit is particularly configured to: acquire voltage information between the first end and the second end of the switch module; and, when it is determined that the voltage between the first end and the second end of the switch module is equal to or greater than zero, control the second switch tube to be closed; and, when it is determined that the first switch tube and the second switch tube are both in a closed state, acquire a target temperature of the battery pack; and, when it is determined that the first switch tube and the second switch tube are both in a closed state, control the three-phase inverter to adjust the amplitude and frequency of a self-heating current of the battery pack according to the target temperature of the battery pack, thereby heating the battery pack to the target temperature.

[0102] In some embodiments, the control component is further configured to set a target self-heating current of the battery pack to zero after the temperature information of the battery pack determines that the battery pack does not require self-heating.

[0103] In some embodiments, the control component is particularly configured to first control the second switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is greater than zero, then obtain current information between the first end and the second end of the switch module, and control the first switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is less than a first preset current; first control the first switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is less than zero, then obtain current information between the first end and the second end of the switch module, and control the first switch tube to be open when the current between the first end and the second end of the switch module is greater than a second preset current; and particularly configured to control the first contactor to be open when the first switch tube and the second switch tube are both determined to be in an open state.

[0104] In some embodiments, the switch module includes a first switch tube, a second switch tube, a first freewheeling diode, and a second freewheeling diode. A first end of the first switch tube is connected to a first node, and a second end of the first switch tube is connected to a second end of the second switch tube. The first end of the second switch tube is connected to a neutral point of a three-phase motor. An anode of the first freewheeling diode is connected to the second end of the first switch tube, and a cathode of the first freewheeling diode is connected to the first end of the first switch tube. An anode of the second freewheeling diode is connected to the second end of the second switch tube, and a cathode of the second freewheeling diode is connected to the first end of the second switch tube.

[0105] In some embodiments, the switch module includes a first switch tube and a second switch tube, a first end of the first switch tube connected to a second end of the second switch tube and connected to a first node, and a second end of the first switch tube connected to the first end of the second switch tube and connected to a neutral point of a three-phase motor.

[0106] In some embodiments, the switch module further includes a first freewheeling diode and a second freewheeling diode, the anode of the first freewheeling diode being connected to the second end of the second switch tube and the cathode of the first freewheeling diode being connected to the first end of the first switch tube, the anode of the second freewheeling diode being connected to the second end of the first switch tube and the cathode of the second freewheeling diode being connected to the first end of the second switch tube.

[0107] In some embodiments, the control component is configured to first control the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, and then obtain voltage information between the first end and the second end of the switch module and control the first switch tube to be closed when the voltage between the first end and the second end of the switch module is determined to be equal to or less than zero, or to first control the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, and then The control circuit is particularly configured to: acquire voltage information between the first end and the second end of the switch module; and, when it is determined that the voltage between the first end and the second end of the switch module is equal to or greater than zero, control the second switch tube to be closed; and, when it is determined that the first switch tube and the second switch tube are both in a closed state, acquire a target temperature of the battery pack; and, when it is determined that the first switch tube and the second switch tube are both in a closed state, control the three-phase inverter to adjust the amplitude and frequency of a self-heating current of the battery pack according to the target temperature of the battery pack, thereby heating the battery pack to the target temperature.

[0108] In some embodiments, the control component is further configured to set a target self-heating current of the battery pack to zero after the temperature information of the battery pack determines that the battery pack does not require self-heating.

[0109] In some embodiments, the control component is specifically configured to: first control the second switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is greater than zero; then obtain current information between the first end and the second end of the switch module; and control the first switch tube to be open when the current between the first end and the second end of the switch module is determined to be less than a third preset current, thereby allowing both the first switch tube and the second switch tube to be in an open state; and to: first control the first switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is less than zero; then obtain current information between the first end and the second end of the switch module; and control the second switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is greater than a fourth preset current, thereby allowing both the first switch tube and the second switch tube to be in an open state.

[0110] In conclusion, in the embodiments of the present disclosure, the switch devices and contactors of the switch module are opened and closed quickly and do not generate impulse voltages and impulse currents, so as to reduce electrical stress when the switch module is closed or opened, achieve the best closing or opening effect, reduce the possibility of damage to the device, and maximize the service life of the electrical equipment.

[0111] It should be noted that for the specific implementation of the battery self-heating system in this embodiment, please refer to the specific implementation of the control method for the battery self-heating system in the above-mentioned embodiment, and the details will not be described again in this specification.

[0112] FIG. 20 is a structural block diagram of an electric vehicle according to one embodiment of the present disclosure.

[0113] Furthermore, the present disclosure provides an electric vehicle 100. The electric vehicle 100 includes the battery self-heating system 1 in the above-described embodiment.

[0114] According to the electric vehicle in this embodiment of the present disclosure, through the self-heating system in the above-mentioned embodiment, the battery can be precisely controlled to self-heat, so as to ensure that the battery can perform normal self-heating operation and to improve the efficiency of charging and discharging the battery.

[0115] Additionally, other components and functions of the electric vehicle in this embodiment of the present disclosure are known to those skilled in the art and will not be described in detail herein to reduce redundancy.

Claims

1. 1. A method for controlling a battery self-heating system, comprising: acquiring temperature information of a battery pack, the battery pack comprising a first battery body and a second battery body, the first battery body and the second battery body being connected in series and having a first node, a three-phase inverter being connected to the battery pack and a three-phase motor, a first end of a switch module being connected to the first node, and a second end of the switch module being connected to a neutral point of the three-phase motor; When it is determined that the battery pack requires self-heating based on the temperature information of the battery pack, acquiring voltage information between a first end and a second end of the switch module, controlling the switch module to be closed according to the voltage information between the first end and the second end of the switch module, and controlling the three-phase inverter to enable the first battery body and the second battery body to be alternately charged and discharged, thereby realizing self-heating of the battery pack; A method for controlling a battery self-heating system, comprising: acquiring current information between the first end and the second end of the switch module when it is determined from the temperature information of the battery pack that the battery pack does not require self-heating; and controlling the switch module to open in accordance with the current information between the first end and the second end of the switch module.

2. The switch module comprises a first switch tube, a second switch tube, a first freewheeling diode, a second freewheeling diode, and a first contactor, a first end of the first switch tube connected to the first node, a second end of the first switch tube connected to a second end of the second switch tube, a first end of the second switch tube connected to one end of the first contactor, and a second end of the first contactor connected to the neutral point of the three-phase motor.

2. The control method of claim 1, wherein an anode of the first freewheeling diode is connected to the second end of the first switch tube, a cathode of the first freewheeling diode is connected to the first end of the first switch tube, an anode of the second freewheeling diode is connected to the second end of the second switch tube, and a cathode of the second freewheeling diode is connected to the first end of the second switch tube.

3. 3. The control method according to claim 1, wherein the switch module comprises a first switch tube, a second switch tube, and a first contactor, a first end of the first switch tube connected to a second end of the second switch tube and connected to the first node, a second end of the first switch tube connected to a first end of the second switch tube and connected to one end of the first contactor, and the other end of the first contactor connected to the neutral point of the three-phase motor.

4. 4. The control method of claim 3, wherein the switch module further comprises a first freewheeling diode and a second freewheeling diode, an anode of the first freewheeling diode connected to the second end of the second switch tube, a cathode of the first freewheeling diode connected to the first end of the first switch tube, an anode of the second freewheeling diode connected to the second end of the first switch tube, and a cathode of the second freewheeling diode connected to the first end of the second switch tube.

5. 5. The control method according to claim 2, further comprising controlling the first contactor to be closed after it is determined that the battery pack requires self-heating based on the temperature information of the battery pack.

6. controlling the switch module in response to the voltage information between the first end and the second end of the switch module; first controlling the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, then obtaining voltage information between the first end and the second end of the switch module, and controlling the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, or first controlling the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, then obtaining voltage information between the first end and the second end of the switch module, and controlling the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than or equal to zero; When it is determined that both the first switch conduit and the second switch conduit are in a closed state, obtaining a target temperature of the battery pack; 6. The control method of claim 5, further comprising: controlling the three-phase inverter to adjust an amplitude and a frequency of a self-heating current of the battery pack according to the target temperature of the battery pack, thereby heating the battery pack to the target temperature.

7. 7. The control method of claim 6, further comprising setting a target self-heating current of the battery pack to zero after the temperature information of the battery pack determines that the battery pack does not require self-heating.

8. controlling the switch module in response to the current information between the first end and the second end of the switch module; first controlling the second switch tube to be opened when the current information determines that the current between the first end and the second end of the switch module is greater than zero; then obtaining the current information between the first end and the second end of the switch module, and controlling the first switch tube to be opened when the current between the first end and the second end of the switch module is determined to be less than a first preset current; first controlling the first switch tube to be opened when the current information determines that the current between the first end and the second end of the switch module is less than zero; then obtaining the current information between the first end and the second end of the switch module, and controlling the first switch tube to be opened when the current between the first end and the second end of the switch module is determined to exceed a second preset current; 8. The control method of claim 7, further comprising: controlling the first contactor to be open when it is determined that the first switch tube and the second switch tube are both in an open state.

9. 9. The control method according to claim 1, wherein the switch module comprises a first switch tube, a second switch tube, a first freewheeling diode, and a second freewheeling diode, a first end of the first switch tube connected to the first node, a second end of the first switch tube connected to the second end of the second switch tube, a first end of the second switch tube connected to the neutral point of the three-phase motor, an anode of the first freewheeling diode connected to the second end of the first switch tube, a cathode of the first freewheeling diode connected to the first end of the first switch tube, an anode of the second freewheeling diode connected to the second end of the second switch tube, and a cathode of the second freewheeling diode connected to the first end of the second switch tube.

10. 10. The control method according to claim 1, wherein the switch module comprises a first switch tube and a second switch tube, a first end of the first switch tube is connected to a second end of the second switch tube and connected to the first node, and a second end of the first switch tube is connected to a first end of the second switch tube and connected to the neutral point of the three-phase motor.

11. 11. The control method of claim 10, wherein the switch module further comprises a first freewheeling diode and a second freewheeling diode, an anode of the first freewheeling diode connected to the second end of the second switch tube, a cathode of the first freewheeling diode connected to the first end of the first switch tube, an anode of the second freewheeling diode connected to the second end of the first switch tube, and a cathode of the second freewheeling diode connected to the first end of the second switch tube.

12. controlling the switch module in response to the voltage information between the first end and the second end of the switch module; first controlling the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than zero, then obtaining the voltage information between the first end and the second end of the switch module, and controlling the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, or first controlling the first switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is less than zero, then obtaining voltage information between the first end and the second end of the switch module, and controlling the second switch tube to be closed when the voltage information determines that the voltage between the first end and the second end of the switch module is greater than or equal to zero; When it is determined that both the first switch conduit and the second switch conduit are in a closed state, obtaining a target temperature of the battery pack; 12. The control method according to claim 9, further comprising: controlling the three-phase inverter to adjust an amplitude and a frequency of a self-heating current of the battery pack according to the target temperature of the battery pack, thereby heating the battery pack to the target temperature.

13. 13. The control method of claim 12, further comprising setting a target self-heating current of the battery pack to zero after the temperature information of the battery pack determines that the battery pack does not require self-heating.

14. controlling the switch module in response to the current information between the first end and the second end of the switch module; first controlling the second switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is greater than zero; then obtaining the current information between the first end and the second end of the switch module, and controlling the first switch tube to be open when the current between the first end and the second end of the switch module is determined to be less than a third preset current, allowing both the first switch tube and the second switch tube to be in an open state; 14. The control method of claim 13, comprising: first controlling the first switch tube to be open when the current information determines that the current between the first end and the second end of the switch module is less than zero; then obtaining the current information between the first end and the second end of the switch module; and controlling the second switch tube to be open when the current between the first end and the second end of the switch module is determined to exceed a fourth preset current, thereby allowing both the first switch tube and the second switch tube to be in an open state.

15. A battery self-heating system comprising a three-phase motor, a battery pack, a three-phase inverter, a switch module, and a control component, wherein the battery pack comprises a first battery body and a second battery body, the first battery body and the second battery body being connected in series and having a first node, the three-phase inverter being connected to the battery pack and the three-phase motor, a first end of the switch module being connected to the first node and a second end of the switch module being connected to a neutral point of the three-phase motor, the control component being connected to the three-phase motor, the battery pack, the three-phase inverter, and the switch module, and the control component comprising: a switch module configured to acquire voltage information between a first end and a second end of the switch module when the temperature information of the battery pack determines that the battery pack requires self-heating; and a switch module configured to control the switch module in accordance with the voltage information between the first end and the second end of the switch module to realize self-heating of the battery pack; and a switch module configured to acquire current information between the first end and the second end of the switch module when the temperature information of the battery pack determines that the battery pack does not require self-heating; and a switch module configured to control the switch module in accordance with the current information between the first end and the second end of the switch module to prevent the battery pack from self-heating.

16. An electric vehicle comprising the battery self-heating system of claim 15.

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