Battery control system and vehicle

Abstract

The present disclosure relates to a battery control system and a vehicle, the battery control system comprising a charge-discharge port, a power battery pack, an inverter and a multiphase motor, the power battery pack comprising a first battery group and a second battery group connected in series; the inverter comprising a first bridge arm group and a second bridge arm group connected in parallel; the multiphase motor comprising a first set of windings and a second set of windings, a first end of the first set of windings being connected to the first bridge arm group, a second end of the first set of windings being connected to a positive electrode of the charge-discharge port, a first end of the second set of windings being connected to the second bridge arm group, and a second end of the second set of windings being connected between the first battery group and the second battery group; the first bridge arm group and the first set of windings being capable of forming a boost charging loop with the power battery pack and the charge-discharge port; and the second bridge arm group and the second set of windings being capable of forming a self-heating loop with the power battery pack.

Description

Technical Field

[0001] This disclosure relates to the field of vehicle control technology, and more specifically, to a battery control system and a vehicle. Background Technology

[0002] Lithium-ion batteries are sensitive to low temperatures. At low temperatures, the internal resistance of lithium-ion batteries increases sharply, which greatly limits the discharge capacity and charge / discharge performance, resulting in insufficient power performance and a significantly shortened driving range for electric vehicles in low-temperature environments.

[0003] To address the charging, discharging, and self-heating requirements of vehicle power battery packs, related technologies typically employ the reuse of single-phase windings from the vehicle's motors to charge or self-heat the power batteries. However, as the number of motors on vehicles increases, so does the number of motor winding phases. These technologies have not considered how to more rationally utilize multi-winding motors to achieve coordinated charging and self-heating of the power batteries. Summary of the Invention

[0004] The purpose of this disclosure is to provide a battery control system and a vehicle. The power battery pack includes a first battery group and a second battery group connected in series. The inverter includes a first bridge arm group and a second bridge arm group. The multiphase motor includes a first set of windings and a second set of windings. The first bridge arm group and the first set of windings can form a boost charging circuit with the power battery pack and the charging / discharging port, so that the power battery pack can be boosted and charged by the electrical energy input through the charging / discharging port. The second bridge arm group and the second set of windings can form a self-heating circuit with the power battery pack, so that the first battery group and the second battery group can alternately charge and discharge to heat the power battery pack, thereby achieving the synergy of boost charging and self-heating of the power battery pack.

[0005] To achieve the above objectives, according to a first aspect of the present disclosure, a battery control system is provided, the system comprising: Charging / discharging port; A power battery pack, the power battery pack comprising a first battery pack and a second battery pack connected in series; An inverter, comprising a first bridge arm group and a second bridge arm group connected in parallel, wherein the first ends of the first bridge arm group and the second bridge arm group are connected together to form a first bus terminal, and the second ends of the first bridge arm group and the second bridge arm group are connected together to form a second bus terminal, wherein the first bus terminal is connected to the positive terminal of the first battery pack, and the second bus terminal is connected to the negative terminal of the second battery pack and the negative terminal of the charging and discharging port. A multiphase motor, comprising a first set of windings and a second set of windings, wherein a first end of the first set of windings is connected to the first bridge arm group, a second end of the first set of windings is connected to the positive terminal of the charging / discharging port, a first end of the second set of windings is connected to the second bridge arm group, and a second end of the second set of windings is connected between the first battery pack and the second battery pack. The first bridge arm assembly and the first set of windings can form a boost charging circuit with the power battery pack and the charging / discharging port; The second bridge arm assembly and the second set of windings can form a self-heating circuit with the power battery pack.

[0006] Optionally, the first bridge arm group includes a multi-phase first bridge arm, the first set of windings includes multiple first pole pairs, each first pole pair includes three first coil branches, the first ends of the coil branches of the same phase in the three first coil branches of the multiple first pole pairs are connected together and connected to the midpoint of the corresponding first bridge arm, the second ends of the three first coil branches of each first pole pair are connected together to form a neutral point, all neutral points of the first set of windings are connected together and a first N line is led out, the first N line is connected to the positive terminal of the charging and discharging port.

[0007] Optionally, the second bridge arm group includes a multi-phase second bridge arm, the second set of windings includes multiple second pole pairs, each second pole pair includes three second coil branches, the first ends of the coil branches of the same phase in the three second coil branches of the multiple second pole pairs are connected together and connected to the midpoint of the corresponding second bridge arm, the second ends of the three second coil branches of each second pole pair are connected together to form a neutral point, part of the neutral points of the second set of windings are connected together and a second N line is led out, the second N line is connected between the first battery pack and the second battery pack.

[0008] Optionally, the system further includes: A charging on / off switch unit, the charging on / off switch unit being configured to: enable or disconnect the boost charging circuit; The self-heating on / off switch unit is configured to enable or disable the self-heating circuit.

[0009] Optionally, the system further includes: The controller is connected to the first bridge arm group, the second bridge arm group, the charging on / off switch unit, and the self-heating on / off switch unit, respectively. The controller is configured to control the first bridge arm group, the second bridge arm group, the charging on / off switch unit, and the self-heating on / off switch unit, so that at least one of the charging / discharging function, the self-heating function, and the driving function is realized.

[0010] Optionally, the controller is configured to: when in the first state, control the second axle arm group and the self-heating on / off switch unit, so that the first battery pack and the second battery pack alternately charge and discharge to heat the power battery pack, and control the first axle arm group so that the electrical energy of the power battery pack is output to the first winding to drive the vehicle.

[0011] Optionally, the controller is configured to: when in the second state, control the first bridge arm group and the charging on / off switch unit so that the electrical energy input through the charging / discharging port is output to the power battery to charge the power battery; and control the second bridge arm group and the self-heating on / off switch unit so that the first battery pack and the second battery pack are alternately charged and discharged to heat the power battery pack.

[0012] Optionally, the controller is configured to: when in the third state, control the first bridge arm group and the charging on / off switch unit so that the electrical energy output by the power battery is output to the charging / discharging port to power the load; and control the second bridge arm group and the self-heating on / off switch unit so that the first battery pack and the second battery pack are charged and discharged alternately to heat the power battery pack.

[0013] Optionally, the controller is configured to: when in the fourth state, control the first bridge arm group and the charging on / off switch unit so that the electrical energy output by the power battery is output to the charging / discharging port to power the load, and control the second bridge arm group so that the electrical energy of the power battery pack is output to the second set of windings to drive the vehicle.

[0014] Optionally, the controller is configured to: when in the fifth state, control the first axle arm group and the charging on / off switch unit so that the electrical energy input through the charging / discharging port is output to the power battery to charge the power battery, and control the second axle arm group so that the electrical energy of the power battery pack is output to the second set of windings to drive the vehicle.

[0015] Optionally, the controller is configured to: when in the sixth state, control the first axle arm group and the charging on / off switch unit so that the electrical energy input through the charging / discharging port is output to the power battery to charge the power battery, and control the second axle arm group and the self-heating on / off switch unit so that the first battery pack and the second battery pack alternately charge and discharge to heat the power battery pack, and so that the electrical energy of the power battery pack is output to the second set of windings to drive the vehicle.

[0016] Optionally, the controller is configured to: control the phases of the first bridge arm group and the second bridge arm group to be the same, control the phases of any two phase bridge arms in the first bridge arm group to be staggered, and control the phases of any two phase bridge arms in the second bridge arm group to be staggered.

[0017] Optionally, the controller is configured to: control the phases of the first bridge arm group and the second bridge arm group to be staggered, control the phases of all bridge arms in the first bridge arm group to be the same, and control the phases of all bridge arms in the second bridge arm group to be the same.

[0018] Optionally, the controller is configured to: control the phases of the first bridge arm group and the second bridge arm group to be staggered, and control the phases of any two phase arms in the first bridge arm group to be staggered, and control the phases of any two phase arms in the second bridge arm group to be staggered.

[0019] According to a second aspect of the present disclosure, a vehicle is provided, including the battery control system provided in the first aspect of the present disclosure.

[0020] Through the above technical solution, the power battery pack includes a first battery group and a second battery group connected in series, the inverter includes a first bridge arm group and a second bridge arm group, and the multiphase motor includes a first set of windings and a second set of windings. The first bridge arm group and the first set of windings can form a boost charging circuit with the power battery pack and the charging / discharging port, so that the power battery pack can be boosted and charged by the electrical energy input through the charging / discharging port. The second bridge arm group and the second set of windings can form a self-heating circuit with the power battery pack and the charging / discharging port, so that the first battery group and the second battery group can alternately charge and discharge to heat the power battery pack. The boost charging and self-heating of the power battery pack can be achieved synergistically, thereby realizing the synergy of boost charging and self-heating of the power battery pack.

[0021] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0022] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram illustrating a battery control system according to an exemplary embodiment.

[0023] Figure 2 This is a schematic diagram illustrating another battery control system according to an exemplary embodiment.

[0024] Figure 3This is a schematic diagram illustrating yet another battery control system according to an exemplary embodiment.

[0025] Figure 4 This is a schematic diagram illustrating another battery control system according to an exemplary embodiment.

[0026] Figure 5 This is a schematic diagram illustrating the current flow direction in a first control stage according to an exemplary embodiment.

[0027] Figure 6 This is a schematic diagram illustrating the current flow direction in a second control stage according to an exemplary embodiment.

[0028] Figure 7 This is a schematic diagram illustrating the current flow direction in a third control stage according to an exemplary embodiment.

[0029] Figure 8 This is a schematic diagram illustrating the current flow direction in a fourth control stage according to an exemplary embodiment.

[0030] Explanation of reference numerals in the attached figures 1. Charging / discharging port; 2. Power battery pack; 21. First battery pack; 22. Second battery pack; 3. Inverter; 31. First bridge arm group; 32. Second bridge arm group; 4. Multiphase motor; 41. First winding; 42. Second winding. Detailed Implementation

[0031] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0032] As vehicles accumulate more and more motors, the number of winding phases in these motors also increases. To meet the charging, discharging, and self-heating requirements of vehicle power battery packs, related technologies typically reuse single-phase windings of the vehicle's motors to charge or self-heat the power battery. This approach fails to make reasonable use of motors with multiple windings and cannot achieve coordinated boost charging and self-heating of the power battery pack.

[0033] To address the aforementioned technical issues, in this embodiment of the disclosure, the power battery pack includes a first battery group and a second battery group connected in series, the inverter includes a first bridge arm group and a second bridge arm group, and the multiphase motor includes a first set of windings and a second set of windings. The first bridge arm group and the first set of windings can form a boost charging circuit with the power battery pack and the charging / discharging port, enabling the power battery pack to be boost-charged by the electrical energy input through the charging / discharging port. The second bridge arm group and the second set of windings can form a self-heating circuit with the power battery pack and the charging / discharging port, allowing the first battery group and the second battery group to alternately charge and discharge to heat the power battery pack, thereby achieving the synergy of boost charging and self-heating of the power battery pack.

[0034] Figure 1 This is a schematic diagram illustrating a battery control system according to an exemplary embodiment, such as... Figure 1 As shown, the battery control system includes: The charging / discharging port 1 is used to output or input electrical energy. For example, the charging / discharging port 1 can be connected to a discharge gun or other load to supply power to other loads. The charging / discharging port 1 can also be connected to a charging gun or charging device to receive electrical energy to charge the power battery pack 2. The charging device can be a wireless charging device or a photovoltaic charging device.

[0035] The power battery pack 2 includes a first battery group 21 and a second battery group 22 connected in series. Each battery group may consist of multiple battery cells (or battery nodes) connected in series. The first battery group 21 and the second battery group 22 may contain the same number of battery cells. The total number of battery cells in the power battery pack 2 may be even.

[0036] Inverter 3 includes a first bridge arm group 31 and a second bridge arm group 32 connected in parallel. The first ends of the first bridge arm group 31 and the second bridge arm group 32 are connected together to form a first bus terminal, and the second ends of the first bridge arm group 31 and the second bridge arm group 32 are connected together to form a second bus terminal. The first bus terminal is connected to the positive terminal of the first battery pack 21, and the second bus terminal is connected to the negative terminal of the second battery pack 22 and the negative terminal of the charging / discharging port 1, respectively.

[0037] The multiphase motor 4 includes a first set of windings 41 and a second set of windings 42. The first end of the first set of windings 41 is connected to the first bridge arm group 31, and the second end of the first set of windings 41 is connected to the positive terminal of the charging and discharging port 1. The first end of the second set of windings 42 is connected to the second bridge arm group 32, and the second end of the second set of windings 42 is connected between the first battery pack 21 and the second battery pack 22.

[0038] Based on the connection structure of the battery control system described above, the first bridge arm group 31 and the first set of windings 41 can form a boost charging circuit with the power battery pack 2 and the charging / discharging port 1, enabling the power battery pack 2 to be boost-charged by the electrical energy input through the charging / discharging port 1. The second bridge arm group 32 and the second set of windings 42 can form a self-heating circuit with the power battery pack 2 and the charging / discharging port 1, allowing the first battery group 21 and the second battery group 22 to alternately charge and discharge, thereby heating the power battery pack 2. This achieves the synergy of boost charging and self-heating of the power battery pack 2.

[0039] Figure 2 This is a schematic diagram illustrating another battery control system according to an exemplary embodiment, such as... Figure 2 As shown, the first bridge arm group 31 includes a multi-phase first bridge arm, such as... Figure 2 As shown, the first bridge arm group 31 can be an ABC bridge arm, and the first winding 41 includes multiple first pole pairs, each first pole pair including three first coil branches, such as... Figure 2 As shown, the first winding 41 may include two first pole pairs, for example, the two first pole pairs may be A1B1C1 pole pairs and A2B2C2 pole pairs. The first ends of the coil branches of the same phase in the three first coil branches of the multiple first pole pairs are connected together and connected to the midpoint of the corresponding first bridge arm. For example, A1 and A2 are connected together and connected to the A bridge arm. The second ends of the three first coil branches of each first pole pair are connected together to form a neutral point, such as... Figure 2 In the first winding 41, all neutral points of n1 and n2 are connected together and the first N line is led out, as shown in the example. Figure 2 In this embodiment, the first N-line of the first set of windings 41 is connected to the positive terminal of the charging / discharging port 1. The first ends of the multiple first pairs of poles of the first set of windings 41 are connected to the first bridge arm group 31. All neutral points of the multiple pairs of poles are connected to the positive terminal of the charging / discharging port 1 via first N-lines. This allows a boost charging circuit to be formed using all the pairs of poles in the first set of windings 41, the first bridge arm group 31, the power battery pack 2, and the charging / discharging port 1. This enables the electrical energy input through the charging / discharging port 1 to be used to boost-charge the power battery pack 2 through all the first pairs of poles in the first set of windings 41 and the first bridge arm group 31. The power energy of the power battery pack 2 can also be output to the charging / discharging port 1 through this boost charging circuit to supply power to the load.

[0040] In one possible implementation, depending on actual needs, a portion of the neutral points of multiple pairs of electrodes can be led out and connected to the positive terminal of the charging / discharging port 1 via a first N line. This allows a boost charging circuit to be formed using a portion of the pairs of electrodes in the first set of windings 41, the first bridge arm group 31, the power battery pack 2, and the charging / discharging port 1. This enables the electrical energy input through the charging / discharging port 1 to boost the power battery pack 2 via a portion of the first pairs of electrodes in the first set of windings 41 and the first bridge arm group 31.

[0041] In one possible implementation, the second arm group 32 includes a multi-phase second arm, such as... Figure 2 As shown, the second bridge arm group 32 can be a UVW bridge arm, and the second winding 42 includes multiple second pole pairs, such as... Figure 2 As shown, the second set of windings 42 may include two second pole pairs, for example, the two second pole pairs may be U1V1W1 pole pairs and U2V2W2 pole pairs. Each second pole pair includes three second coil branches. The first ends of the coil branches of the same phase in the three second coil branches of multiple second pole pairs are connected together and connected to the midpoint of the corresponding second bridge arm. For example, U1 and U2 are connected together and connected to the U bridge arm. The second ends of the three second coil branches of each second pole pair are connected together to form a neutral point, such as... Figure 2 In the second set of windings 42, n3 and n4 are connected together at part of the neutral point and the second N line is led out, as shown in the example. Figure 2 In this embodiment, the first end of the plurality of second pairs of electrodes of the second winding 42 is connected to the second bridge arm group 32, and the neutral point of a portion of the plurality of pairs of electrodes leads out the second N line and connects to the positive terminal of the charging / discharging port 1, so that a self-heating circuit can be formed by using a portion of the pairs of electrodes in the second winding 42, the second bridge arm group 32 and the power battery, so that the first battery pack 21 and the second battery pack 22 are alternately charged and discharged to heat the power battery pack 2.

[0042] In one possible implementation, depending on actual needs, all neutral points of multiple pairs of electrodes can be led out to the second N line and connected to the positive terminal of the charging / discharging port 1, so that a self-heating circuit can be formed using some pairs of electrodes in the second set of windings 42, the second bridge arm group 32, and the power battery, so that the first battery pack 21 and the second battery pack 22 can be charged and discharged alternately to heat the power battery pack 2.

[0043] Figure 3 This is a schematic diagram illustrating yet another battery control system according to an exemplary embodiment. Figure 4 This is a schematic diagram illustrating another battery control system according to an exemplary embodiment, such as... Figure 3 and Figure 4 As shown, for example, such as Figure 3 All neutral points of the first winding 41 can be connected together. Figure 3 Connect n1 and n2 in the first N line, and connect all the neutral points of the second set of windings 42 together. Figure 3 n3 and n4 in the middle, and draw out the second N line; such as Figure 4 As shown, one neutral point of the first winding 41 can be... Figure 4 n2 in the middle leads to the first N line, which connects to a neutral point of the second winding 42. Figure 4 The second N-line is drawn from n3 in the diagram. This allows for selection of the connection method based on the actual needs of charging / discharging and self-heating.

[0044] In one possible implementation, the battery control system further includes a charging on / off switch unit and a self-heating on / off switch unit. The charging on / off switch unit is configured to either turn the boost charging circuit on or off. When the boost charging circuit is on, the power battery pack 2 can be boost-charged or de-charged to supply power to the load. The self-heating on / off switch unit is configured to either turn the self-heating circuit on or off. When the self-heating circuit is on, alternating charging and discharging between the first battery pack 21 and the second battery pack 22 can be achieved through the self-heating circuit to heat the power battery pack 2.

[0045] In one possible implementation, the battery control system further includes a switching assembly, which may include a charging on / off switch unit and a self-heating on / off switch unit. Specifically, the switching assembly may include a first switch, a second switch, a third switch, a fourth switch, and a fifth switch. The first switch is located on the connection line between the positive terminal of the first battery pack 21 and the first busbar; the second switch is located on the connection line between the negative terminal of the second battery pack 22 and the second busbar; the third switch is located on the connection line between the second end of the first winding and the positive terminal of the charging / discharging port 1; the fourth switch is located on the connection line between the second busbar and the negative terminal of the charging / discharging port 1; and the fifth switch is located on the connection line between the second end of the second winding and the first battery pack 21 and the second battery pack 22. Figure 2 As shown, the first switch can be K1, the second switch can be K2, the third switch can be K3, the fourth switch can be K4, and the fifth switch can be K5.

[0046] The charging on / off switch unit may include a first switch, a second switch, a third switch, and a fourth switch, while the self-heating on / off switch unit may include a first switch, a second switch, and a fifth switch.

[0047] In one possible implementation, the battery control system further includes a controller, which may be a Microcontroller Unit (MCU). This controller is connected to the first bridge arm group 31, the second bridge arm group 32, the charging on / off switch unit, and the self-heating on / off switch unit, respectively. The controller is configured to control the first bridge arm group 31, the second bridge arm group 32, the charging on / off switch unit, and the self-heating on / off switch unit, enabling at least one of the following functions: charging / discharging, self-heating, and driving. That is, by controlling the first bridge arm group 31, the second bridge arm group 32, the charging on / off switch unit, and the self-heating on / off switch unit, the following can be achieved: coordination between self-heating and driving functions; coordination between self-heating and charging functions; coordination between self-heating and discharging functions; coordination between discharging and driving functions; coordination between charging and driving functions; and coordination between charging, driving, and self-heating functions.

[0048] In one possible implementation, for the coordination of the self-heating function and the driving function, the controller is configured to: when in a first state, control the second axle arm assembly 32 and the self-heating on / off switch unit, causing the first battery pack 21 and the second battery pack 22 to alternately charge and discharge to heat the power battery pack 2, and control the first axle arm assembly 31 so that the electrical energy of the power battery pack 2 is output to the first winding 41 to drive the vehicle. The first state can be a coordinated mode of the self-heating function and the driving function.

[0049] For example, the first set of windings 41 can be controlled to achieve the driving function and the second set of windings 42 can be controlled to achieve the self-heating function. The control method can be: the first control stage, the second control stage, the third control stage and the fourth control stage are executed in sequence to achieve the coordination of the self-heating function and the driving function.

[0050] The first control stage can be to close the first, second, and fifth switches, open the other switches in the switch assembly, connect the upper bridge arm in the second bridge arm group 32, disconnect the lower bridge arm of the second bridge arm group 32, so that the first battery pack 21 can charge the second winding 42, and control the first bridge arm group 31 so that the power battery pack 2 can output electrical energy to the first winding 41 to drive the vehicle.

[0051] The second control phase involves closing the first, second, and fifth switches, opening the other switches in the switch assembly, opening the upper arm of the second axle arm group 32, opening the lower arm of the second axle arm group 32, connecting the second winding 42 to charge the second battery pack 22, and controlling the first axle arm group 31 to output the electrical energy of the power battery pack 2 to the first winding 41 to drive the vehicle.

[0052] The third control stage involves closing the second and fifth switches, opening the other switches in the switch assembly, opening the upper bridge arm in the second bridge arm group 32, and connecting the lower bridge arm of the second bridge arm group 32, so that the second battery pack 22 can charge the second winding 42.

[0053] The fourth control stage involves closing the first and fifth switches, opening the other switches in the switch assembly, connecting the upper bridge arm in the second bridge arm group 32, and disconnecting the lower bridge arm in the second bridge arm group 32, so that the second winding 42 charges the first battery pack 21.

[0054] For example, in another possible control method, the second set of windings 42 can be controlled to simultaneously realize the self-heating function and the driving function. The control method can be: sequentially executing the first control stage, the second control stage, the third control stage and the fourth control stage to realize the synergy of the self-heating function and the driving function. The first control stage can be to close the first switch, the second switch, and the fifth switch, open the other switches in the switch assembly, connect the upper bridge arm in the second bridge arm group 32, and disconnect the lower bridge arm of the second bridge arm group 32, so that the first battery pack 21 can charge the second winding 42, and the electrical energy of the first battery pack 21 can be output to the second winding 42 to drive the vehicle.

[0055] The second control stage involves closing the first, second, and fifth switches, opening the other switches in the switch assembly, opening the upper bridge arm in the second bridge arm group 32, and connecting the lower bridge arm of the second bridge arm group 32, so that the second winding 42 charges the second battery pack 22.

[0056] The third control stage involves closing the second and fifth switches, opening the other switches in the control switch assembly, opening the upper bridge arm in the second bridge arm group 32, opening the lower bridge arm of the second bridge arm group 32, and connecting the second battery pack 22 to charge the second winding 42, and outputting the electrical energy of the second battery pack 22 to the second winding 42 to drive the vehicle.

[0057] The fourth control stage involves closing the first and fifth switches, opening the other switches in the switch assembly, connecting the upper bridge arm in the second bridge arm group 32, and disconnecting the lower bridge arm in the second bridge arm group 32, so that the second winding 42 charges the first battery pack 21.

[0058] In this embodiment, the first winding 41 can be controlled to perform the driving function and the second winding 42 can be controlled to perform the self-heating function. Alternatively, the second winding 42 can be controlled to perform both the self-heating and driving functions simultaneously, achieving synergy between the self-heating and driving functions. This allows the power battery pack 2 to continuously self-heat while the vehicle is in motion, thereby improving its discharge performance. The self-heating of the power battery pack 2 can heat itself, or provide heating to the passenger compartment, the steering wheel, or the seats through the vehicle's heat exchange system, significantly enhancing the performance of the power battery pack 2.

[0059] In one possible implementation, for the coordination of the self-heating function and the charging function, the controller is configured to: when in the second state, control the first bridge arm group 31 and the charging on / off switch unit so that the electrical energy input through the charging / discharging port 1 is output to the power battery to charge the power battery; and control the second bridge arm group 32 and the self-heating on / off switch unit so that the first battery pack 21 and the second battery pack 22 are alternately charged and discharged to heat the power battery pack 2. The second state can be a coordinated mode of the self-heating function and the charging function.

[0060] For example, the boost charging function can be realized through the first set of windings 41, and the self-heating function can be realized through the second set of windings 42. The control method can be: sequentially executing the first control stage, the second control stage, the third control stage and the fourth control stage, so that the charging and discharging port boosts the power battery pack 2 and the power battery pack 2 self-heats. Figure 5 This is a schematic diagram illustrating the current flow direction in a first control stage according to an exemplary embodiment. Figure 6 This is a schematic diagram illustrating the current flow direction in a second control stage according to an exemplary embodiment. Figure 7 This is a schematic diagram illustrating the current flow direction in a third control stage according to an exemplary embodiment. Figure 8 This is a schematic diagram illustrating the current flow in a fourth control stage according to an exemplary embodiment. In the figure, the current flow for the boost charging function is represented by [insert current flow here], and the current flow for the self-heating function is represented by [insert current flow here].

[0061] like Figure 5 As shown, the first control stage involves closing the first, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower bridge arm of the first bridge arm group 31, and opening the upper bridge arm of the first bridge arm group 31, so that the electrical energy input from the charging / discharging port 1 charges the first winding 41. It also involves connecting the upper bridge arm of the second bridge arm group 32 and opening the lower bridge arm of the second bridge arm group 32, so that the first battery pack 21 charges the second winding 42.

[0062] like Figure 6 As shown, the second control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first bridge arm group 31, and opening the lower arm of the first bridge arm group 31, so that the charging / discharging port 1 and the second set of windings 42 simultaneously charge the power battery pack 2 to achieve boost charging. It also involves connecting the lower arm of the second bridge arm group 32 and opening the upper arm of the second bridge arm group 32, so that the second set of windings 42 charges the second battery pack 22.

[0063] like Figure 7 As shown, the third control stage involves closing the second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower bridge arm of the first bridge arm group 31, and opening the upper bridge arm of the first bridge arm group 31, so that the electrical energy input from the charging / discharging port 1 charges the first winding 41. It also involves connecting the lower bridge arm of the second bridge arm group 32 and opening the upper bridge arm of the second bridge arm group 32, so that the second battery pack 22 charges the second winding 42.

[0064] like Figure 8 As shown, the fourth control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first bridge arm group 31, and opening the lower arm of the first bridge arm group 31, so that the charging / discharging port 1 and the second set of windings 42 simultaneously charge the power battery pack 2 to achieve boost charging. It also involves connecting the upper arm of the second bridge arm group 32 and opening the lower arm of the second bridge arm group 32, so that the second set of windings 42 charges the first battery pack 21.

[0065] In this embodiment, boost charging is achieved through the first set of windings 41, and self-heating is achieved through the second set of windings 42, thus enabling the synergy of boost charging and self-heating. When the external charging voltage is less than or equal to the voltage of the power battery pack 2, boost charging can be achieved through the first set of windings 41, and self-heating of the power battery pack 2 can be achieved through the second set of windings 42 during charging, raising the temperature of the power battery pack 2 for better charging. The charging process itself also accelerates battery heat generation; the combined heat generation from charging and self-heating can be used to heat both the power battery pack 2 and the passenger compartment. This allows for rapid heating of the power battery pack 2, improving its charging performance and shortening charging time in low-temperature environments.

[0066] In one possible implementation, for the coordination of the self-heating and discharging functions, the controller is configured to: when in the third state, control the first bridge arm group 31 and the charging on / off switch unit, so that the electrical energy output by the power battery is output to the charging / discharging port 1 to power the load; and control the second bridge arm group 32 and the self-heating on / off switch unit, so that the first battery pack 21 and the second battery pack 22 are alternately charged and discharged to heat the power battery pack 2. The third state can be a coordinated mode of the self-heating and discharging functions.

[0067] For example, the first set of windings 41 can be controlled to perform the discharge function and the second set of windings 42 can be controlled to perform the self-heating function. The control method can be: sequentially executing the first control stage, the second control stage, the third control stage and the fourth control stage, so that the charging and discharging port performs voltage reduction discharge on the power battery pack 2 and the power battery pack 2 performs self-heating. The first control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first bridge arm group 31, and disconnecting the lower arm of the first bridge arm group 31. This allows the power battery pack 2 to charge the first winding 41 while simultaneously outputting electrical energy to the charging / discharging port 1. It also involves connecting the upper arm of the second bridge arm group 32 and disconnecting the lower arm of the second bridge arm group 32, allowing the first battery pack 21 to charge the second winding 42.

[0068] The second control stage involves closing the second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower bridge arm of the first bridge arm group 31, opening the upper bridge arm of the first bridge arm group 31, allowing the second winding 42 to output electrical energy to the charging / discharging port 1, connecting the lower bridge arm of the second bridge arm group 32, and opening the upper bridge arm of the second bridge arm group 32, allowing the second winding 42 to charge the second battery pack 22.

[0069] The third control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first bridge arm group 31, and disconnecting the lower arm of the first bridge arm group 31. This allows the power battery pack 2 to charge the first winding 41 while simultaneously outputting electrical energy to the charging / discharging port 1. It also involves connecting the lower arm of the second bridge arm group 32 and disconnecting the upper arm of the second bridge arm group 32, allowing the second battery pack 22 to charge the second winding 42.

[0070] The fourth control stage involves closing the first, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower bridge arm of the first bridge arm group 31, opening the upper bridge arm of the first bridge arm group 31, allowing the second winding 42 to output electrical energy to the charging / discharging port 1, connecting the upper bridge arm of the second bridge arm group 32, and opening the lower bridge arm of the second bridge arm group 32, allowing the second winding 42 to charge the first battery pack 21.

[0071] In this embodiment, the first winding 41 can be controlled to achieve the discharge function, and the second winding 42 can be controlled to achieve the self-heating function, so as to achieve the synergy of voltage reduction discharge and self-heating. An external load can be connected through the charging / discharging port 1. The external load can be a computer, mobile phone, tablet, rice cooker, or other electrical tools. When the voltage of the power battery pack 2 is greater than the operating voltage of the external load, voltage reduction charging can be achieved through the first winding 41, and self-heating of the power battery pack 2 can be achieved through the second winding 42 during the discharge process, thereby increasing the temperature of the power battery pack 2 and improving the discharge performance of the power battery pack 2.

[0072] In one possible implementation, for the coordination of the discharge and drive functions, the controller is configured to: when in the fourth state, control the first axle arm group 31 and the charging on / off switch unit, so that the electrical energy output from the power battery is output to the charging / discharging port 1 to power the load, and control the second axle arm group 32, so that the electrical energy of the power battery pack 2 is output to the second winding 42 to drive the vehicle. The fourth state can be a coordinated mode of the discharge and drive functions.

[0073] For example, the first set of windings 41 can be controlled to perform the discharge function and the second set of windings 42 can be controlled to perform the driving function. The control method can be: the first control stage and the second control stage are executed in sequence to achieve the coordination of the discharge function and the driving function.

[0074] The first control stage can be to control the first switch, the second switch, the third switch and the fourth switch to close, control the other switches in the switch assembly to open, control the upper bridge arm of the first bridge arm group 31 to connect, control the lower bridge arm of the first bridge arm group 31 to disconnect, so that the power battery pack 2 charges the first set of windings 41 and outputs electrical energy to the charging and discharging port 1, and controls the second bridge arm group 32 so that the electrical energy of the power battery pack 2 is output to the second set of windings 42 to drive the vehicle.

[0075] The second control stage can be to control the first switch, the second switch, the third switch and the fourth switch to close, control the other switches in the switch assembly to open, control the lower bridge arm of the first bridge arm group 31 to connect, control the upper bridge arm of the first bridge arm group 31 to disconnect, so that the first set of windings 41 outputs electrical energy to the charging and discharging port 1, and control the second bridge arm group 32 so that the electrical energy of the power battery pack 2 is output to the second set of windings 42 to drive the vehicle.

[0076] In this embodiment, the first winding 41 can be controlled to perform a discharge function, and the second winding 42 can be controlled to perform a driving function, so as to achieve the coordination of the discharge function and the driving function. This is to meet the power needs of users in the vehicle when the vehicle is in motion. For example, to supply power to the laptops, tablets, or mobile phones of users in the vehicle.

[0077] In one possible implementation, for the coordination of charging and driving functions, the controller is configured to: when in the fifth state, control the first axle arm group 31 and the charging on / off switch unit, so that the electrical energy input through the charging / discharging port 1 is output to the power battery to charge the power battery, and control the second axle arm group 32, so that the electrical energy of the power battery pack 2 is output to the second winding 42 to drive the vehicle. The fifth state can be a coordinated mode of charging and driving functions.

[0078] For example, the first set of windings 41 can be controlled to realize the charging function and the second set of windings 42 can be controlled to realize the driving function. The control method can be: the first control stage and the second control stage are executed in sequence to realize the coordination of the charging function and the driving function.

[0079] The first control stage can be to control the first switch, the second switch, the third switch and the fourth switch to close, control the other switches in the switch assembly to open, control the lower bridge arm of the first bridge arm group 31 to connect, control the upper bridge arm of the first bridge arm group 31 to disconnect, so that the electrical energy input from the charging and discharging port 1 charges the first winding 41, and control the second bridge arm group 32 so that the electrical energy of the power battery pack 2 is output to the second winding 42 to drive the vehicle.

[0080] The second control stage can be to control the first switch, the second switch, the third switch, and the fourth switch to close, and control the other switches in the switch assembly to open, and control the upper bridge arm of the first bridge arm group 31 to connect, and control the lower bridge arm of the first bridge arm group 31 to disconnect, so that the charging and discharging port 1 and the second set of windings 42 simultaneously charge the power battery pack 2 to achieve boost charging, and control the second bridge arm group 32 so that the electrical energy of the power battery pack 2 is output to the second set of windings 42 to drive the vehicle.

[0081] In this embodiment, the first set of windings 41 can be controlled to perform the charging function, and the second set of windings 42 can be controlled to perform the driving function, so as to achieve the synergy between the charging and driving functions. The charging function can be wireless charging or photovoltaic charging. For example, for wireless charging, wireless coil charging equipment can be laid on the road, and the vehicle can be wirelessly charged while driving. It is also possible for two moving vehicles to wirelessly charge and discharge each other for vehicle rescue. For photovoltaic charging, a photovoltaic power generation device can be installed on the vehicle, and the power generated by the power generation device can be used to boost the voltage of the power battery pack 2 through the first set of windings 41 to improve the vehicle's driving range.

[0082] In one possible implementation, the controller is configured to coordinate the charging, driving, and self-heating functions. When in the sixth state, it controls the first axle arm assembly 31 and the charging on / off switch unit, causing electrical energy input through the charging / discharging port 1 to be output to the power battery for charging. Simultaneously, it controls the second axle arm assembly 32 and the self-heating on / off switch unit, causing the first battery pack 21 and the second battery pack 22 to alternately charge and discharge to heat the power battery pack 2, and causing electrical energy from the power battery pack 2 to be output to the second winding 42 to drive the vehicle. The sixth state can be a coordinated mode of charging, driving, and self-heating functions.

[0083] For example, the charging function can be realized through the first set of windings 41, and the self-heating and driving functions can be realized through the second set of windings 42. The control method can be: the first control stage, the second control stage, the third control stage and the fourth control stage are executed in sequence to realize the coordination of the charging function, the driving function and the self-heating function. The first control stage involves closing the first, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower arm of the first axle arm group 31, and disconnecting the upper arm of the first axle arm group 31, so that the electrical energy input from the charging / discharging port 1 charges the first winding 41. It also involves connecting the upper arm of the second axle arm group 32, disconnecting the lower arm of the second axle arm group 32, so that the first battery pack 21 charges the second winding 42, and outputting the electrical energy from the first battery pack 21 to the second winding 42 to drive the vehicle.

[0084] The second control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first bridge arm group 31, and disconnecting the lower arm of the first bridge arm group 31, so that the charging / discharging port 1 and the second set of windings 42 simultaneously charge the power battery pack 2 to achieve boost charging. It also involves connecting the lower arm of the second bridge arm group 32 and disconnecting the upper arm of the second bridge arm group 32, so that the second set of windings 42 charges the second battery pack 22.

[0085] The third control stage involves closing the second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower arm of the first axle arm group 31, and disconnecting the upper arm of the first axle arm group 31, so that the electrical energy input from the charging / discharging port 1 charges the first winding 41. It also involves connecting the lower arm of the second axle arm group 32, disconnecting the upper arm of the second axle arm group 32, so that the second battery pack 22 charges the second winding 42, and outputting electrical energy from the second battery pack 22 to the second winding 42 to drive the vehicle.

[0086] The fourth control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first bridge arm group 31, and disconnecting the lower arm of the first bridge arm group 31, so that the charging / discharging port 1 and the second set of windings 42 simultaneously charge the power battery pack 2 to achieve boost charging. It also involves connecting the upper arm of the second bridge arm group 32 and disconnecting the lower arm of the second bridge arm group 32, so that the second set of windings 42 charges the first battery pack 21.

[0087] In this embodiment, the charging function is achieved through the first set of windings 41, and the self-heating and driving functions are achieved through the second set of windings 42, so as to realize the synergy of the charging function, driving function and self-heating function. This enables wireless charging / photovoltaic charging of the power battery pack 2 and self-heating of the power battery pack 2 while driving, so as to improve the charging performance of the power battery pack 2 and increase the vehicle's driving range by raising the temperature of the power battery pack 2 through self-heating.

[0088] In one possible implementation, the discharge function, drive function, and self-heating function can also be coordinated. The controller is configured to: when in the seventh state, control the first bridge arm group 31 and the charging on / off switch unit, so that the electrical energy output by the power battery is output to the charging / discharging port 1 to power the load; and control the second bridge arm group 32 and the self-heating on / off switch unit, so that the first battery pack 21 and the second battery pack 22 are alternately charged and discharged to heat the power battery pack 2, and so that the electrical energy of the power battery pack 2 is output to the second winding 42 to drive the vehicle. The seventh state can be a coordinated mode of the discharge function, drive function, and self-heating function.

[0089] For example, the discharge function can be realized through the first set of windings 41, and the self-heating and driving functions can be realized through the second set of windings 42. The control method can be: the first control stage, the second control stage, the third control stage and the fourth control stage are executed in sequence to realize the coordination of the discharge function, the driving function and the self-heating function. The first control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first axle arm group 31, and disconnecting the lower arm of the first axle arm group 31. This allows the power battery pack 2 to charge the first winding 41 while simultaneously outputting electrical energy to the charging / discharging port 1. It also involves connecting the upper arm of the second axle arm group 32 and disconnecting the lower arm of the second axle arm group 32. This allows the first battery pack 21 to charge the second winding 42 and output electrical energy from the first battery pack 21 to the second winding 42 to drive the vehicle. The second control stage involves closing the second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower bridge arm of the first bridge arm group 31, opening the upper bridge arm of the first bridge arm group 31, allowing the second winding 42 to output electrical energy to the charging / discharging port 1, connecting the lower bridge arm of the second bridge arm group 32, opening the upper bridge arm of the second bridge arm group 32, and charging the second battery pack 22 with the second winding 42. The third control stage involves closing the first, second, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the upper arm of the first axle arm group 31, and disconnecting the lower arm of the first axle arm group 31. This allows the power battery pack 2 to charge the first winding 41 while simultaneously outputting electrical energy to the charging / discharging port 1. It also involves connecting the lower arm of the second axle arm group 32, disconnecting the upper arm of the second axle arm group 32, allowing the second battery pack 22 to charge the second winding 42, and outputting electrical energy from the second battery pack 22 to the second winding 42 to drive the vehicle. The fourth control stage involves closing the first, third, fourth, and fifth switches, opening the other switches in the switch assembly, connecting the lower bridge arm of the first bridge arm group 31, opening the upper bridge arm of the first bridge arm group 31, allowing the second winding 42 to output electrical energy to the charging / discharging port 1, connecting the upper bridge arm of the second bridge arm group 32, and opening the lower bridge arm of the second bridge arm group 32, allowing the second winding 42 to charge the first battery pack 21.

[0090] In this embodiment, the discharge function is achieved through the first set of windings 41, and the self-heating and driving functions are achieved through the second set of windings 42, so as to realize the synergy of the discharge function, driving function and self-heating function. Thus, when the vehicle is in motion, it can provide electrical energy to the load of the user in the vehicle and self-heat the power battery pack 2, so as to improve the temperature of the power battery pack 2 through self-heating, thereby improving the discharge performance of the power battery pack 2.

[0091] In one possible implementation, the first bus terminal can also be connected to the positive terminal of the charging / discharging port 1, and a sixth switch can be provided on this connection line. There can also be an eighth state, which can be a direct charging mode. This eighth state allows the electrical energy input from the charging / discharging port 1 to directly charge the power battery pack 2 by controlling the first, second, fourth, and sixth switches. For example, when the voltage of the charging gun or charging device connected to the charging / discharging port 1 is higher than the voltage of the power battery pack 2, direct charging can be performed. When the voltage of the charging gun or charging device connected to the charging / discharging port 1 is equal to or lower than the voltage of the power battery pack 2, boost charging can be performed.

[0092] The first bridge arm group 31 and the second bridge arm group 32 can also be asynchronously controlled to reduce ripple.

[0093] In one possible implementation, the controller can be configured to: control the phases of the first bridge arm group 31 and the second bridge arm group 32 to be the same, and control the phases of any two phase arms in the first bridge arm group 31 to be staggered, and control the phases of any two phase arms in the second bridge arm group 32 to be staggered. This achieves synchronous control between the first bridge arm group 31 and the second bridge arm group 32, and asynchronous control within the bridge arm group. Synchronous control means that the phases of the controlled objects are the same, and asynchronous control means that the phases of the controlled objects are staggered.

[0094] In one possible implementation, the controller can be configured to: control the phases of the first bridge arm group 31 and the second bridge arm group 32 to be staggered, and control the phases of all bridge arms in the first bridge arm group 31 to be the same, and control the phases of all bridge arms in the second bridge arm group 32 to be the same. This achieves asynchronous control between the first bridge arm group 31 and the second bridge arm group 32, and synchronous control within the bridge arm groups.

[0095] In one possible implementation, the controller can be configured to: control the phases of the first bridge arm group 31 and the second bridge arm group 32 to be staggered, and control the phases of any two phase arms in the first bridge arm group 31 to be staggered, and control the phases of any two phase arms in the second bridge arm group 32 to be staggered. This achieves asynchronous control between the first bridge arm group 31 and the second bridge arm group 32, and asynchronous control within the bridge arm group.

[0096] For example, each phase of the ABC bridge arms can be staggered by a certain phase the1, and each phase of the UVW bridge arms can also be staggered by a certain phase the2, and the ABC bridge arms and UVW bridge arms can be uniformly staggered by a certain angle the3 (the1, the2, the3 ∈ (0, 360)). For example, the1 = 120 electrical degrees, the2 = 120 electrical degrees, and the3 = 60 electrical degrees. If the first bridge arm group 31 is phase p1 and the second bridge arm group 32 is phase p2, then preferably the1 = 360 / p1 electrical degrees, the2 = 360 / p2 electrical degrees, and the3 = 360 / (p1+p2) electrical degrees.

[0097] In one possible implementation, the controller can control the first bridge arm group 31, the second bridge arm group 32, the charging on / off switch unit, and the self-heating on / off switch unit through control commands, so that at least one of the charging / discharging function, the self-heating function, and the driving function can be realized.

[0098] The control commands may include switch control commands and bridge arm control commands. Switch control commands control the charging on / off switch unit and the self-heating on / off switch unit. Bridge arm control commands control the first bridge arm group 31 and the second bridge arm group 32. The bridge arm control commands may include the duty cycle of each phase bridge arm. Whether it's self-heating, boost charging, or buck discharging, the corresponding function is achieved through common-mode voltage control. The drive function is controlled by the differential-mode voltage of the bridge arm. The common-mode voltage and differential-mode voltage are added together to obtain the control voltage for each phase bridge arm. By modulating the duty cycle of the bridge arm output, each function can be independently controlled to achieve its corresponding function.

[0099] Among them, capacitor C1 is connected in parallel across the two ends of the power battery pack, and capacitor C2 is connected in parallel across the two ends of the charging and discharging port. During the entire control process, boost charging and discharging commands*, battery self-heating current amplitude commands*, self-heating current frequency commands*, and self-heating battery balancing current commands* can be obtained. ① Self-heating function of the power battery pack: The battery self-heating current amplitude command*, self-heating current frequency command*, and self-heating battery active balancing current command* are given a self-heating current amplitude of ipk_x, a current frequency of f_x, and a self-heating battery active balancing current of indc_x. The resulting line current on line N_x is in_x* = indc_x + ipk_x *sin(2pi*f_x*t) or in_x* = indc_x + ipk_x *cos(2pi*f_x*t). The required current value in_x* and the actual current value in_x (in_1 = -ia-ib-ic or in_2 = -iu-iv-iw) are used by PI or PR closed-loop control to obtain the required duty cycle Dn_x. The common-mode duty cycle of the upper bridge arm is Dp_x = 1 - Dn_x. Here, p refers to the number of motor phases in each dq coordinate system, x refers to the x-th system, x=1 refers to the first dq coordinate system, x=2 refers to the second dq coordinate system. A second set of dq coordinate system can be used for self-heating, x=2, each set of windings has three phases, and here each set of system has p=1, 2, 3.

[0100] ②Charging and discharging function of the power battery pack: Charge / discharge command*: The charge / discharge command* determines whether to perform direct charging or boost charging based on the voltage level of the charging station and battery pack.

[0101] When the voltage of the charging pile is higher than the voltage of the power battery pack, direct charging and discharging is selected, i.e., closed circuit. Figure 2 The bridge arms corresponding to the K1, K2, K3, K6, ABC three-phase windings are not controlled.

[0102] When the voltage of the charging pile is lower than the voltage of the power battery pack, boost charging and discharging are selected, and the circuit is closed. Figure 2 K1, K2, K3, and K4.

[0103] When the external power supply connected to the external charging / discharging port circuit is in constant current charging / discharging mode, the electric drive system adopts voltage and current dual closed-loop control. The required voltage value Un1* and the actual Un1 (Un1 is obtained by sampling the voltage on capacitor C2) are controlled in a closed loop to obtain the required current command In*. The required current value in1* and the actual current value in1 (obtained from the sampled currents ia, ib, and ic, in1 = -ia - ib - ic) are added together and controlled in a PID closed-loop to obtain the required control voltage Un_1 (common-mode voltage value). The control voltage value of each phase bridge arm is equal to the common-mode voltage Un_1. By modulating the control voltage value of each phase bridge arm with the bus voltage and the carrier wave, the PWM duty cycle of each phase bridge arm is obtained. Through the modulation effect of the bridge arm, the required motor current value for each phase is obtained.

[0104] When the external power supply connected to the external charging / discharging port circuit is in constant current charging / discharging mode, the electric drive system can also adopt single-voltage closed-loop control: In the voltage closed-loop stage, the required charging port voltage command Unx* is obtained according to the command calculation module. The required voltage value Unx* and the actual Unx (Un1 is obtained by sampling the voltage on capacitor C2, and Un2 is obtained by sampling the voltage on capacitor C2) are used to derive the required control voltage Un_x (common-mode voltage value) through closed-loop control. The control voltage value of each phase bridge arm is equal to the common-mode voltage Un_x. By modulating the control voltage value of each phase bridge arm with the bus voltage and the carrier wave, the PWM common-mode duty cycle Dp_x of each phase bridge arm in the x-th dq coordinate system is obtained. Through the modulation effect of the bridge arm, the required motor current value for each phase is obtained. The first dq coordinate system can be used for boost charging, x=1.

[0105] The actual current on the N line is calculated using in1=-ia-ib-ic, and the current in1 on the N line is used for current monitoring and protection.

[0106] When the external power supply connected to the external charging / discharging port circuit is in constant voltage charging / discharging mode, the motor controller adopts single current upper closed-loop control: the current command In* is directly given by the command calculation module, without a voltage closed-loop component.

[0107] ③ Torque control of drive function: Each dq coordinate system obtains the target torque for control. Based on the target torque command*, motor speed value, and battery bus voltage, the target id_x* and iq_x* that satisfy the torque command are found through the MTPA & MTPV curves (the MTPA & MTPV curves can be pre-calculated and bench-calibrated, and the target current command id_x* and iq_x* can be obtained from voltage, torque, and speed using a lookup table or linear fitting method). After the calculation process, the target id_x* and iq_x* are obtained, and the current vector on the dq axis is controlled in a closed loop according to the motor's vector control method. The sampled phase current values ​​i1_x, i2_x, ..., ip_x are transformed to the αβ coordinate system iα_x, iβ_x through Clark coordinate transformation, and then transformed to the dq coordinate system through Park coordinate transformation to obtain the direct-axis current id_x and quadrature-axis current iq_x. The difference between the current target values ​​id_x* and id_x is used to output the target value Ud_x through PID control. The difference between the current target values ​​iq_x* and iq_x is used to output the target value Uq_x through PID control. Ud_x and Uq_x are transformed into Uα_x and Uβ_x through inverse Park transformation. Uα_x and Uβ_x are transformed into U1_x, U2_x, ..., Up_x through inverse Clark transformation. The control voltage values ​​of each phase bridge arm are modulated with the bus voltage and carrier wave to obtain the PWM differential duty cycle DD1_x, DD2_x, ..., DDp_x of each phase bridge arm in phase p_x. In DDp_x, p refers to the number of motor phases in each dq coordinate system, x=1 refers to the first dq coordinate system, x=2 refers to the second dq coordinate system, and so on. Figure 2 A six-phase motor with two sets of windings, each set of windings having three phases. Here, the p=1, 2, 3 of each system are: A phase differential duty cycle DD1_1, B phase differential duty cycle DD2_1, C phase differential duty cycle DD3_1, U phase differential duty cycle DD1_2, V phase differential duty cycle DD2_2, and W phase differential duty cycle DD3_2.

[0108] In another exemplary embodiment, a vehicle is also provided, including the battery charging system provided in the embodiments of this disclosure.

[0109] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0110] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0111] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A battery control system, characterized in that, The system includes: Charging / discharging port (1); The power battery pack (2) includes a first battery pack (21) and a second battery pack (22) connected in series. Inverter (3), the inverter (3) includes a first bridge arm group (31) and a second bridge arm group (32) connected in parallel. The first ends of the first bridge arm group (31) and the second bridge arm group (32) are connected together to form a first bus terminal. The second ends of the first bridge arm group (31) and the second bridge arm group (32) are connected together to form a second bus terminal. The first bus terminal is connected to the positive terminal of the first battery pack (21). The second bus terminal is connected to the negative terminal of the second battery pack (22) and the negative terminal of the charging and discharging port (1). A multiphase motor (4) includes a first set of windings (41) and a second set of windings (42). The first end of the first set of windings (41) is connected to the first bridge arm group (31), and the second end of the first set of windings (41) is connected to the positive terminal of the charging and discharging port (1). The first end of the second set of windings (42) is connected to the second bridge arm group (32), and the second end of the second set of windings (42) is connected between the first battery pack (21) and the second battery pack (22). The first bridge arm assembly (31) and the first set of windings (41) can form a boost charging circuit with the power battery pack (2) and the charging and discharging port (1); The second bridge arm assembly (32) and the second set of windings (42) can form a self-heating circuit with the power battery pack (2).

2. The battery control system according to claim 1, characterized in that, The first bridge arm group (31) includes a multi-phase first bridge arm, and the first set of windings (41) includes multiple first pole pairs. Each first pole pair includes three first coil branches. The first ends of the coil branches of the same phase in the three first coil branches of the multiple first pole pairs are connected together and connected to the midpoint of the corresponding first bridge arm. The second ends of the three first coil branches of each first pole pair are connected together to form a neutral point. All neutral points of the first set of windings (41) are connected together and a first N line is led out. The first N line is connected to the positive terminal of the charging and discharging port (1).

3. The battery control system according to claim 1, characterized in that, The second bridge arm group (32) includes a multi-phase second bridge arm, and the second set of windings (42) includes multiple second pole pairs. Each second pole pair includes three second coil branches. The first ends of the coil branches of the same phase in the three second coil branches of the multiple second pole pairs are connected together and connected to the midpoint of the corresponding second bridge arm. The second ends of the three second coil branches of each second pole pair are connected together to form a neutral point. Part of the neutral points of the second set of windings (42) are connected together and a second N line is led out. The second N line is connected between the first battery pack (21) and the second battery pack (22).

4. The battery control system according to claim 1, characterized in that, The system also includes: A charging on / off switch unit, the charging on / off switch unit being configured to: enable or disconnect the boost charging circuit; The self-heating on / off switch unit is configured to enable or disable the self-heating circuit.

5. The battery control system according to claim 4, characterized in that, The system also includes: The controller is connected to the first bridge arm group (31), the second bridge arm group (32), the charging on / off switch unit and the self-heating on / off switch unit respectively; The controller is configured to control the first bridge arm group (31), the second bridge arm group (32), the charging on / off switch unit and the self-heating on / off switch unit, so that at least one of the charging / discharging function, the self-heating function and the driving function is realized.

6. The battery control system according to claim 5, characterized in that, The controller is configured to: when in the first state, control the second axle arm group (32) and the self-heating on / off switch unit so that the first battery pack (21) and the second battery pack (22) alternately charge and discharge to heat the power battery pack (2), and control the first axle arm group (31) so that the electrical energy of the power battery pack (2) is output to the first winding (41) and / or output to the second winding (42) to drive the vehicle.

7. The battery control system according to claim 5, characterized in that, The controller is configured to: when in the second state, control the first bridge arm group (31) and the charging on / off switch unit so that the electrical energy input through the charging / discharging port (1) is output to the power battery to charge the power battery pack (2); and control the second bridge arm group (32) and the self-heating on / off switch unit so that the first battery pack (21) and the second battery pack (22) are charged and discharged alternately to heat the power battery pack (2).

8. The battery control system according to claim 5, characterized in that, The controller is configured to: when in the third state, control the first bridge arm group (31) and the charging on / off switch unit so that the electrical energy output by the power battery is output to the charging / discharging port (1) to power the load; and control the second bridge arm group (32) and the self-heating on / off switch unit so that the first battery pack (21) and the second battery pack (22) are charged and discharged alternately to heat the power battery pack (2).

9. The battery control system according to claim 5, characterized in that, The controller is configured to: when in the fourth state, control the first bridge arm group (31) and the charging on / off switch unit so that the electrical energy output by the power battery is output to the charging / discharging port (1) to power the load, and control the second bridge arm group (32) so that the electrical energy of the power battery pack (2) is output to the second winding (42) and / or output to the first winding (41) to drive the vehicle.

10. The battery control system according to claim 5, characterized in that, The controller is configured to: when in the fifth state, control the first axle arm group (31) and the charging on / off switch unit so that the electrical energy input through the charging / discharging port (1) is output to the power battery to charge the power battery pack (2), and control the second axle arm group (32) so that the electrical energy of the power battery pack (2) is output to the second winding (42) and / or output to the first winding (41) to drive the vehicle.

11. The battery control system according to claim 5, characterized in that, The controller is configured to: when in the sixth state, control the first axle arm group (31) and the charging on / off switch unit so that the electrical energy input through the charging / discharging port (1) is output to the power battery to charge the power battery pack (2), and control the second axle arm group (32) and the self-heating on / off switch unit so that the first battery pack (21) and the second battery pack (22) are alternately charged and discharged to heat the power battery pack (2), and so that the electrical energy of the power battery pack (2) is output to the second winding (42) and / or output to the first winding (41) to drive the vehicle.

12. The battery control system according to claim 5, characterized in that, The controller is configured to: control the phases of the first bridge arm group (31) and the second bridge arm group (32) to be the same, and control the phases of any two phase arms in the first bridge arm group (31) to be staggered, and control the phases of any two phase arms in the second bridge arm group (32) to be staggered.

13. The battery control system according to claim 5, characterized in that, The controller is configured to: control the phases of the first bridge arm group (31) and the second bridge arm group (32) to be staggered, and control the phases of all bridge arms in the first bridge arm group (31) to be the same, and control the phases of all bridge arms in the second bridge arm group (32) to be the same.

14. The battery control system according to claim 5, characterized in that, The controller is configured to: control the phases between the first bridge arm group (31) and the second bridge arm group (32) to be staggered, and control the phases of any two phase arms in the first bridge arm group (31) to be staggered, and control the phases of any two phase arms in the second bridge arm group (32) to be staggered. The controller is configured to: control the phase between the first bridge arm group (31) and the second bridge arm group (32) to be the same, and control the phase of all bridge arms in the first bridge arm group (31) to be the same, and control the phase of all bridge arms in the first bridge arm group (32) to be the same.

15. A vehicle, characterized in that, The battery control system includes any one of claims 1-14 above.

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