Battery pack control system and method for electric vehicle, and electric vehicle

Abstract

A battery pack control system and method for an electric vehicle, and an electric vehicle. The electric vehicle comprises a first electric-motor control circuit, a second electric-motor control circuit and a third electric-motor control circuit. The control system comprises a switch module. The switch module is suitable for connecting to a battery pack, the first electric-motor control circuit, the second electric-motor control circuit, the third electric-motor control circuit and an external power supply device, respectively, and is suitable for controlling the connections between the battery pack, the first electric-motor control circuit, the second electric-motor control circuit, the third electric-motor control circuit and the external power supply device, such that the battery pack operates in one or two operating modes among a self-heating mode, a direct charging mode and a buck charging mode.

Description

Battery pack control system and method of electric vehicle, electric vehicle

[0001] The present application claims priority to the Chinese patent application No. 202411098297.X, filed on August 12, 2024, the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure relates to the technical field of battery control, and in particular to a battery pack control system and method of electric vehicle, and electric vehicle. BACKGROUND

[0003] New energy vehicles are becoming more and more popular in the field of automobiles, however, the charging and discharging performance of the batteries widely used in the field of new energy vehicles is easily affected by the external temperature. SUMMARY

[0004] The present disclosure aims to at least partially solve one of the technical problems in the related art. To this end, the present disclosure proposes a battery pack control system of electric vehicle, which can improve the environmental adaptability of the electric vehicle, reduce the design cost of the electric vehicle, and also ensure the charging efficiency of the battery pack by providing multiple charging modes to the battery pack through the combined use of motor control circuits.

[0005] The present disclosure also proposes an electric vehicle.

[0006] The present disclosure further proposes a battery pack control method of electric vehicle.

[0007] In a first aspect, a battery pack control system of electric vehicle is provided. The electric vehicle includes a first motor control circuit, a second motor control circuit and a third motor control circuit. The control system includes a switch module. The switch module is adapted to be connected between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and an external power supply device, and is adapted to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and the external power supply device, so that the battery pack works in one or two working modes of self-heating mode, direct charging mode and step-down charging mode.

[0008] In the battery pack control system of electric vehicle of some embodiments of the present disclosure, the control system can multiplex the first motor control circuit, the second motor control circuit and the third motor control circuit through the switch module, thereby completing the control of the self-heating, direct charging and step-down charging modes of the battery pack, improving the environmental adaptability of the electric vehicle, reducing the design cost of the electric vehicle, and also ensuring the charging efficiency of the battery pack through the step-down control of the motor control circuit.

[0009] In a second aspect, an electric vehicle is provided. The electric vehicle comprises a controller and the battery pack control system of the electric vehicle. The controller is connected with the switch module, and is configured to configure the switch state of the switch module, the first motor control circuit, the second motor control circuit and the third motor control circuit, so as to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and the external power supply device, so that the battery pack works in one or two working modes of the self-heating mode, the direct charging mode and the step-down charging mode.

[0010] The electric vehicle of some embodiments of the present disclosure can improve the environmental adaptability of the electric vehicle, reduce the design cost of the electric vehicle, and also ensure the charging efficiency of the battery pack through the battery pack control system of the electric vehicle in the above embodiments.

[0011] In a third aspect, a battery pack control method of an electric vehicle is provided. The control method is applied to the electric vehicle of the above embodiments. The control method comprises the following steps: responding to a battery pack control instruction; configuring the switch state of the switch module, the first motor control circuit, the second motor control circuit and the third motor control circuit according to the control instruction, so as to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and the external power supply device, so that the battery pack works in one or two working modes of the self-heating mode, the direct charging mode and the step-down charging mode.

[0012] In the battery pack control method of the electric vehicle of some embodiments of the present disclosure, the battery pack control instruction is first responded to, and then the switch state of the switch module, the first motor control circuit, the second motor control circuit and the third motor control circuit are configured according to the control instruction, so that the first motor control circuit, the second motor control circuit and the third motor control circuit can be multiplexed through the switch module, the control of the self-heating mode, the direct charging mode and the step-down charging mode of the battery pack is completed, the environmental adaptability of the electric vehicle is improved, the design cost of the electric vehicle is reduced, and the charging efficiency of the battery pack is also ensured through the step-down control of the motor control circuit.

[0013] Additional aspects and advantages of the present disclosure will be made apparent from the following description, which is given by way of example only, and with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0014] FIG. 1 is a circuit schematic diagram of a battery pack control system of an electric vehicle according to some embodiments;

[0015] FIG. 2 is another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0016] FIG. 3 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0017] FIG. 4 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0018] FIG. 5 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0019] FIG. 6 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0020] FIG. 7 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0021] FIG. 8 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0022] FIG. 9 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0023] FIG. 10 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0024] FIG. 11 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0025] FIG. 12 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0026] FIG. 13 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0027] FIG. 14 is yet another circuit schematic of a battery pack control system for an electric vehicle, according to some embodiments;

[0028] FIG. 15 is a block diagram of an electric vehicle, according to some embodiments;

[0029] FIG. 16 is a flowchart of a battery pack control method for an electric vehicle, according to some embodiments. DETAILED DESCRIPTION

[0030] Embodiments of the present disclosure are described below in detail with reference to the accompanying drawings, examples of which are shown in the drawings, wherein the same or similar notations represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present disclosure, and cannot be understood as a limitation of the present disclosure.

[0031] To solve the technical problem that the ion activity in the battery pack is very low in a low-temperature environment, so that the battery pack cannot normally provide energy for the vehicle, the technical solution adopted in the related art is to set up an auxiliary heating device to heat the battery pack. However, the related art needs to additionally increase the device, which increases the design cost of the vehicle, and even needs to rewire, and cannot guarantee the charging efficiency of the battery pack.

[0032] To this end, some embodiments of the present disclosure provide a battery pack control system and method of an electric vehicle, and an electric vehicle.

[0033] The battery pack control system and method of an electric vehicle, and the electric vehicle of the embodiments of the present disclosure are described below with reference to the accompanying drawings.

[0034] The electric vehicle generally includes multiple motors, and each motor includes a corresponding control circuit. The motor control circuits corresponding to the three motors in the electric vehicle are multiplexed in the present disclosure to control the battery pack.

[0035] For example, as shown in FIG. 1, the battery pack control system of the electric vehicle in some embodiments of the present disclosure multiplexes the first motor control circuit 11, the second motor control circuit 12, and the third motor control circuit 13. The control system includes a switch module connected between the battery pack, the first motor control circuit 11, the second motor control circuit 12, the third motor control circuit 13, and an external power supply device, and the switch module is composed of multiple switches. Since the switches are distributed at different positions in the system, the switch module is not marked in the figure, but each switch is marked. The switch module is adapted to adjust the energy transmission direction between the battery pack, the first motor control circuit 11, the second motor control circuit 12, the third motor control circuit 13, and the external power supply device, so that the battery pack can work in a self-heating mode, a direct charging mode, or a step-down charging mode, thereby being able to heat the battery pack, charge the battery pack using the external power supply device, and then make the battery pack normally used in a low-temperature environment, and improve the adaptability of the electric vehicle to the environment.

[0036] The motor control circuit is described in detail with reference to FIG. 1. The first motor control circuit 11, the second motor control circuit 12, and the third motor control circuit 13 each include at least one phase sub-circuit. The motor control circuit in some embodiments of the present disclosure can be described using a three-phase sub-circuit. Of course, the motor control circuit can also be extended to a single-phase, five-phase, six-phase circuit, etc. Each phase sub-circuit includes an upper bridge switch tube, a lower bridge switch tube, and a phase inductor. The upper bridge switch tube and the lower bridge switch tube are connected in series between the positive terminal and the negative terminal of the DC bus. The node between the upper bridge switch tube and the lower bridge switch tube is connected to one end of the phase inductor. In the first motor control circuit 11, the other end of the phase inductor in each phase sub-circuit is connected and has a first node P1. In the second motor control circuit 12, the other end of the phase inductor in each phase sub-circuit is connected and has a second node P2. In the third motor control circuit 13, the other end of the phase inductor in each phase sub-circuit is connected and has a third node P3.

[0037] Each phase sub-circuit in the three-phase sub-circuit in the first motor control circuit 11 includes an upper bridge switch tube, a lower bridge switch tube, and a phase inductor. For example, in this three-phase sub-circuit, the first phase sub-circuit includes a first switch tube VT1, a second switch tube VT2, and a first phase inductor L11 connected to the connection node of the first switch tube VT1 and the second switch tube VT2. The second phase sub-circuit includes a third switch tube VT3, a fourth switch tube VT4, and a second phase inductor L12 connected to the connection node of the third switch tube VT3 and the fourth switch tube VT4. The third phase sub-circuit includes a fifth switch tube VT5, a sixth switch tube VT6, and a third phase inductor L13 connected to the connection node of the fifth switch tube VT5 and the sixth switch tube VT6.

[0038] Each phase sub-circuit in the three-phase sub-circuit in the second motor control circuit 12 also includes an upper bridge switch tube, a lower bridge switch tube, and a phase inductor. For example, in this three-phase sub-circuit, the first phase sub-circuit includes a seventh switch tube VT7, an eighth switch tube VT8, and a fourth phase inductor L21 connected to the connection node of the seventh switch tube VT7 and the eighth switch tube VT8. The second phase sub-circuit includes a ninth switch tube VT9, a tenth switch tube VT10, and a fifth phase inductor L22 connected to the connection node of the ninth switch tube VT9 and the tenth switch tube VT10. The third phase sub-circuit includes an eleventh switch tube VT11, a twelfth switch tube VT12, and a sixth phase inductor L23 connected to the connection node of the eleventh switch tube VT11 and the twelfth switch tube VT12.

[0039] Each phase sub-circuit in the three-phase sub-circuit in the third motor control circuit 13 includes an upper bridge switch tube, a lower bridge switch tube, and a phase inductor. For example, in the three-phase sub-circuit, the first phase sub-circuit includes the thirteenth switch tube VT13, the fourteenth switch tube VT14, and the seventh phase inductor L31 connected to the connection node of the thirteenth switch tube VT13 and the fourteenth switch tube VT14; the second phase sub-circuit includes the fifteenth switch tube VT15, the sixteenth switch tube VT16, and the eighth phase inductor L32 connected to the connection node of the fifteenth switch tube VT15 and the sixteenth switch tube VT16; and the third phase sub-circuit includes the seventeenth switch tube VT17, the eighteenth switch tube VT18, and the ninth phase inductor L33 connected to the connection node of the seventeenth switch tube VT17 and the eighteenth switch tube VT18.

[0040] In each of the above-mentioned three-phase sub-circuits, the odd-numbered switch tube can be an upper bridge switch tube, and the even-numbered switch tube can be a lower bridge switch tube. Of course, the limitation of the present embodiment is only for the convenience of describing the scheme, and is not a limitation on the protection scope of the scheme.

[0041] The battery pack includes the first battery module B1 and the second battery module B2, and the external power supply device can also include the first power supply device and the second power supply device. It should be noted that the voltage models of the first power supply device and the second power supply device can be different to adapt to different power supply devices, such as charging piles of different voltage models. Moreover, in some embodiments, the first power supply device and the second power supply device can also be external electric vehicles to realize vehicle-to-vehicle charging and discharging.

[0042] In some embodiments, as shown in FIG. 1, the switch module includes a plurality of switch combinations, each of which can include a plurality of switches in the first switch K1, the second switch K2, the third switch K3, the fourth switch K4, the fifth switch K5, the sixth switch K6, the seventh switch K7, the eighth switch K8, and the ninth switch K9. Different switch combinations correspond to different working modes of the battery pack, and the different switch combinations and the working modes corresponding to the switch combinations are described in detail below.

[0043] One end of the first switch K1 is connected to the positive terminal of the first battery module B1, and the other end of the first switch K1 is connected to the positive terminal of the DC bus. One end of the second switch K2 is connected to the negative terminal of the second battery module B2, and the other end of the second switch K2 is connected to the negative terminal of the DC bus. The negative terminal of the first battery module B1 is connected to the positive terminal of the second battery module B2, and has a fourth node P4. The third switch K3 is connected between the first node P1 and the positive terminal of the first battery module B1. The fourth switch K4 is connected between the third node P3 and the positive terminal of the first battery module B1. The fifth switch K5 is connected between the second node P2 and the fourth node P4. The first power supply device is connected to the DC bus through the sixth switch K6 and the seventh switch K7. The second power supply device is connected to the DC bus through the eighth switch K8 and the ninth switch K9.

[0044] For example, as shown in FIG. 1, the switch module includes nine switches, and the nine switches can form a plurality of different switch combinations, and each switch combination includes a plurality of switches. In addition, the third switch K3 and the fourth switch K4 are connected in series and connected between the first node P1 and the third node P3. The first switch K1 and the second switch K2 are connected at both ends of the battery pack, so that the battery pack is connected to both ends of the DC bus through the first switch K1 and the second switch K2. The first battery module B1 and the second battery module B2 forming the battery pack have a fourth node, and the fourth node is connected to the second node P2 through the fifth switch K5. The first power supply device is connected to the sixth switch K6 and the seventh switch K7 at both ends, one of the sixth switch K6 and the seventh switch K7 is connected to one of the positive terminal and the negative terminal of the DC bus, and the other of the sixth switch K6 and the seventh switch K7 is connected to the other of the positive terminal and the negative terminal of the DC bus. The second power supply device is connected to the eighth switch K8 and the ninth switch K9 at both ends, one of the eighth switch K8 and the ninth switch K9 is connected to one of the positive terminal and the negative terminal of the DC bus, and the other of the eighth switch K8 and the ninth switch K9 is connected to the other of the positive terminal and the negative terminal of the DC bus.

[0045] Some embodiments of the present disclosure can control the battery pack to self-heat by controlling different switch combinations formed by the above-mentioned nine switches, and can also use the first power supply device or the second power supply device to charge. In addition, some embodiments of the present disclosure can also participate in the battery pack charging by using the phase inductance in the motor control circuit, so as to realize the step-down charging of the battery pack.

[0046] In some embodiments, as shown in FIG. 1, the control system further comprises a pre-charge module, which comprises a pre-charge switch K, a pre-charge resistor R and at least one pre-charge capacitor. The at least one pre-charge capacitor is connected between the positive and negative terminals of the DC bus, one end of the pre-charge switch K is connected to the positive terminal of the DC bus, the other end of the pre-charge switch K is connected to one end of the pre-charge resistor R, and the other end of the pre-charge resistor R is connected to the positive terminal of the first battery module B1.

[0047] For example, the at least one pre-charge capacitor can include three pre-charge capacitors, namely a first pre-charge capacitor C1, a second pre-charge capacitor C2 and a third pre-charge capacitor C3, and each pre-charge capacitor can be arranged between the positive and negative terminals of the DC bus. Through the cooperation of the pre-charge resistor R, the pre-charge switch K, the battery pack and the switch mode, the pre-charge capacitor can be charged by the battery pack before the battery pack works in the direct charging mode or the step-down charging mode.

[0048] For another example, before the battery pack works in one mode or two modes among the self-heating mode, the direct charging mode and the step-down charging mode, the pre-charge switch K and the second switch K2 are configured to be in a closed state to charge the at least one pre-charge capacitor by the battery pack.

[0049] As shown in FIG. 2, the pre-charge switch K and the second switch K2 are in a closed state, and the other switches in the switch module are in an open state. In this case, the current in the battery pack is branched after passing through the pre-charge resistor R and the pre-charge switch K, the first current passes through the first pre-charge capacitor C1 and the second switch K2 and then returns to the battery pack, the second current passes through the second pre-charge capacitor C2 and the second switch K2 and then returns to the battery pack, and the third current passes through the third pre-charge capacitor C3 and the second switch K2 and then returns to the battery pack, thereby completing the charging of the first pre-charge capacitor C1, the second pre-charge capacitor C2 and the third pre-charge capacitor C3, i.e., completing the pre-charge of the battery pack. In this way, it can be ensured that the external power supply device will not cause a circuit failure due to instantaneous discharge when pre-charging the battery pack, avoiding damage to the circuit device and improving the service life and use reliability of the battery pack and the electric vehicle.

[0050] It should be noted that the current flow direction during the charging of the pre-charge capacitor by the battery pack can be seen from the arrows in FIG. 2. In addition, in order to ensure stable operation of the circuit, the pre-charge capacitor also needs to be pre-charged before the battery pack works in the self-heating mode.

[0051] In some embodiments, as shown in FIG. 3, the switch combination includes the first switch K1, the second switch K2, the sixth switch K6, and the seventh switch K7. When the first switch K1, the second switch K2, the sixth switch K6, and the seventh switch K7 are configured in a closed state, and the third switch K3, the fourth switch K4, the fifth switch K5, the eighth switch K8, and the ninth switch K9 are configured in an open state, the battery pack is directly charged by the first power supply device, so that the battery pack works in a direct charging mode.

[0052] For example, taking the first power supply device as a charging pile as an example. When the charging gun of the charging pile is connected to the vehicle to charge the battery pack, the sixth switch K6 and the seventh switch K7 are in a closed state, the first switch K1 and the second switch K2 are also in a closed state, and the other switches are configured in an open state. In this case, the first power supply device can directly charge the battery pack, so that the battery pack works in a direct charging mode. In this mode, the current flow between the first power supply device and the battery pack can be seen from the arrows in FIG. 3.

[0053] In some embodiments, as shown in FIG. 4, the switch combination includes the first switch K1, the second switch K2, the eighth switch K8, and the ninth switch K9. When the first switch K1, the second switch K2, the eighth switch K8, and the ninth switch K9 are configured in a closed state, the battery pack is directly charged by the second power supply device, so that the battery pack works in a direct charging mode. In this case, the third switch K3, the fourth switch K4, the fifth switch K5, the sixth switch K6, and the seventh switch K7 are configured in an open state.

[0054] For example, taking the second power supply device as a charging pile as an example. When the charging gun of the charging pile is connected to the vehicle to charge the battery pack, the eighth switch K8 and the ninth switch K9 are in a closed state, the first switch K1 and the second switch K2 are also in a closed state, and the other switches are configured in an open state. In this case, the second power supply device can directly charge the battery pack, so that the battery pack works in a direct charging mode. In this mode, the current flow between the second power supply device and the battery pack can be seen from the arrows in FIG. 4.

[0055] In some embodiments, the switch combination includes the first switch K1, the second switch K2, and the fifth switch K5. When the at least one upper bridge switch tube of the three-phase sub-circuit in the first switch K1, the fifth switch K5, and the second motor control circuit 12 is configured to be in a closed state, and the second switch K2 is configured to be in an open state, the phase inductor corresponding to the at least one upper bridge switch tube is charged by the battery pack, and when the switching states of the first switch K1 and the second switch K2 are replaced, and the switching states of the at least one upper bridge switch tube and the corresponding lower bridge switch tube are replaced, the battery pack is charged by the phase inductor, so that the battery pack works in a self-heating mode. It should be noted that the at least one upper bridge switch tube and the at least one lower bridge switch tube in the embodiment correspond in number and position, and the number of the two can be selected according to actual application.

[0056] In addition, in some embodiments of the disclosure, the other switches in the switch module except the switch combination can be in a default open state. For example, in the above-mentioned embodiment, when the switches included in the switch combination are the first switch K1, the second switch K2, and the fifth switch K5, the third switch K3, the fourth switch K4, the sixth switch K6, the seventh switch K7, the eighth switch K8, and the ninth switch K9 except the switch combination are in a default open state, or the states of the third switch K3, the fourth switch K4, the sixth switch K6, the seventh switch K7, the eighth switch K8, and the ninth switch K9 are not limited, but the positions of the third switch K3, the fourth switch K4, the sixth switch K6, the seventh switch K7, the eighth switch K8, and the ninth switch K9 are set to be open.

[0057] For example, the self-heating has two time sequences, the first time sequence is controlled by the switches to charge the phase inductor by the battery pack, and the second time sequence is controlled by the switches to discharge the energy in the phase inductor to the battery pack. As shown in FIGS. 5 and 6, the first battery module B1 is taken as an example to charge the phase inductor first, and then the phase inductor charges the second battery module B2.

[0058] In some examples, in FIG. 5, the first switch K1, the fifth switch K5, and any upper bridge switch of the three-phase sub-circuit in the second motor control circuit 12 are configured to be in the closed state, and the other switches are configured to be in the open state. In this case, the first battery module B1 forms a current loop with the first switch K1, the upper bridge switch, the phase inductor, and the fifth switch K5, which can charge the phase inductor. When the phase inductor is fully charged or has been charged for a preset time, the second timing can be switched. As shown in FIG. 6, in the second timing, the switching states of the first switch K1 and the second switch K2 are swapped, and the switching states of the upper bridge switch and the corresponding lower bridge switch are swapped, that is, the first switch K1 is configured to be in the open state, the second switch K2 is configured to be in the closed state, and the upper bridge switch is configured to be in the open state, and the corresponding lower bridge switch is configured to be in the closed state.

[0059] In the embodiment shown in FIGS. 5 and 6, the first phase sub-circuit and the corresponding fourth phase inductor L21 in the second motor control circuit 12 can be applied to the self-heating mode of the battery pack. For example, in the first timing, the first switch K1, the seventh switch VT7, and the fifth switch K5 are configured to be in the closed state, so that the first battery module B1 can charge the fourth phase inductor L21. In the second timing, the first switch K1 and the seventh switch VT7 are configured to be in the open state, and the second switch K2 and the eighth switch VT8 are configured to be in the closed state, so that the electrical energy in the fourth phase inductor L21 can be charged into the second battery module B2. Through the charging and discharging operation of the first battery module B1 and the second battery module B2 in the battery pack of this embodiment, the heating effect can be achieved, and this heating method can achieve heating without additional auxiliary heating devices.

[0060] Of course, the functions of the first battery module B1 and the second battery module B2 in the self-heating mode can also be exchanged in this embodiment, that is, the second battery module B2 is used to charge the phase inductor, and the charged phase inductor is used to charge the first battery module B1. For example, when the second switch K2, the fifth switch K5, and at least one lower bridge switch of the three-phase sub-circuit in the second motor control circuit 12 are configured to be in the closed state, and the first switch K1 is configured to be in the open state, the phase inductor corresponding to any lower bridge switch is charged by the battery pack, and when the switching states of the first switch K1 and the second switch K2 are swapped, and the switching states of at least one upper bridge switch and the corresponding lower bridge switch are swapped, the battery pack is charged by the phase inductor, so that the battery pack works in the self-heating mode.

[0061] In some examples, referring to FIG. 7, the second switch K2, the fifth switch K5 and any one of the lower bridge switches of the three-phase sub-circuit in the second motor control circuit 12 are configured to be in the closed state, while the other switches are configured to be in the open state. In this case, the second battery module B2 forms a current loop with the second switch K2, the lower bridge switch, the phase inductor and the fifth switch K5, which can charge the phase inductor. When the phase inductor is fully charged or has been charged for a preset period of time, the second timing sequence can be switched to. As shown in FIG. 8, in the second timing sequence, the switching states of the first switch K1 and the second switch K2 are swapped, and the switching states of the upper bridge switch and the corresponding lower bridge switch are swapped, that is, the second switch K2 is configured to be in the open state, the first switch K1 is configured to be in the closed state, and the lower bridge switch is configured to be in the open state, and the corresponding upper bridge switch is configured to be in the closed state.

[0062] In the embodiment shown in FIGS. 7 and 8, the first phase sub-circuit and the corresponding fourth phase inductor L21 in the second motor control circuit 12 can be applied to the self-heating mode of the battery pack. For example, in the first timing sequence, the second switch K2, the eighth switch VT8 and the fifth switch K5 are configured to be in the closed state, so that the second battery module B2 can charge the fourth phase inductor L21. In the second timing sequence, the second switch K2 and the eighth switch VT8 are configured to be in the open state, while the first switch K1 and the seventh switch VT7 are configured to be in the closed state, so that the electrical energy in the fourth phase inductor L21 can be charged into the first battery module B1. Through the charging and discharging operation of the first battery module B1 and the second battery module B2 in the battery pack of this embodiment, the heating effect can be achieved, and this heating method can achieve heating without additional auxiliary heating devices.

[0063] It should be noted that the application of the switch and the phase inductor shown in FIGS. 5 to 8 is only an example, and in other embodiments, the second phase sub-circuit or the third phase sub-circuit and the corresponding phase inductor can also be used, or even multiple phase sub-circuits can be used at the same time. That is, multiple phase inductors are charged at the same time, and multiple phase inductors can also charge the battery at the same time.

[0064] In some embodiments, the switch combination includes the first switch K1, the second switch K2, the fifth switch K5, the sixth switch K6, and the seventh switch K7. When the at least one upper bridge switch or the at least one lower bridge switch of the three-phase sub-circuit in the second motor control circuit 12 and the first switch K1, the second switch K2, the fifth switch K5, the sixth switch K6, and the seventh switch K7 are configured to be in a closed state, the battery pack is charged by the first power supply device, and the phase inductor corresponding to the at least one upper bridge switch or the phase inductor corresponding to the at least one lower bridge switch is charged by the battery pack. Here, the third switch K3, the fourth switch K4, the eighth switch K8, and the ninth switch K9 are configured to be in an open state, and when the switching state of the at least one upper bridge switch and the corresponding lower bridge switch is replaced, or the switching state of the at least one lower bridge switch and the corresponding upper bridge switch is replaced, the battery pack is charged by the phase inductor to work in the self-heating mode and the direct charging mode.

[0065] For example, as shown in FIG. 3, the first power supply device directly charges the battery pack through the sixth switch K6, the seventh switch K7, the first switch K1, and the second switch K2. During the process of continuously charging the battery pack by the first power supply device, the self-heating of the battery pack is also realized by controlling the related switches and the fifth switch K5 in the second motor control circuit 12. The control in the self-heating process can be referred to the related description of the embodiments corresponding to FIGS. 5 to 8. To avoid redundancy, the description is not repeated here.

[0066] In some embodiments, the switch combination includes the first switch K1, the second switch K2, the fifth switch K5, the eighth switch K8, and the ninth switch K9. When the at least one upper bridge switch or the at least one lower bridge switch of the three-phase sub-circuit in the second motor control circuit 12 and the first switch K1, the second switch K2, the fifth switch K5, the eighth switch K8, and the ninth switch K9 are configured to be in a closed state, the battery pack is charged by the second power supply device, and the phase inductor corresponding to the at least one upper bridge switch or the phase inductor corresponding to the at least one lower bridge switch is charged by the battery pack. Here, the third switch K3, the fourth switch K4, the sixth switch K6, and the seventh switch K7 are configured to be in an open state, and when the switching state of the at least one upper bridge switch and the corresponding lower bridge switch is replaced, or the switching state of the at least one lower bridge switch and the corresponding upper bridge switch is replaced, the battery pack is charged by the phase inductor to work in the self-heating mode and the direct charging mode.

[0067] For example, as shown in FIG. 4, the second power supply device charges the battery pack directly through the eighth switch K8, the ninth switch K9, the first switch K1 and the second switch K2. And in the process of the first power supply device continuously charging the battery pack, the self-heating of the battery pack is also realized through the control of the relevant switch tubes in the second motor control circuit 12 and the fifth switch K5. The control in the self-heating process can refer to the related description of the above-mentioned embodiments corresponding to FIGS. 5 to 8. To avoid redundancy, this will not be described here.

[0068] In some embodiments, the switch combination includes the second switch K2, the third switch K3, the sixth switch K6 and the seventh switch K7. When at least one upper bridge switch tube in the second switch K2, the third switch K3, the sixth switch K6, the seventh switch K7 and the first motor control circuit 11 three-phase sub-circuit is configured to be in a closed state, the first power supply device charges at least one upper bridge switch tube corresponding to the phase inductor and the battery pack, and when the sixth switch K6, the seventh switch K7 and at least one upper bridge switch tube are reconfigured to be in an open state, and the lower bridge switch tube corresponding to at least one upper bridge switch tube is configured to be in a closed state, the battery pack is charged through the phase inductor to work in a step-down charging mode.

[0069] In some examples, the first power supply device also charges the phase inductor corresponding to a phase sub-circuit in the first motor control circuit 11 during the charging of the battery pack, so as to reduce the charging voltage of the battery pack. And when the first power supply device stops charging the battery pack, the charged phase inductor can also continue to charge the battery pack, so that the battery pack can work in a step-down charging mode. The step-down charging mode can be divided into two time sequences according to whether the first power supply device is connected or not.

[0070] For example, as shown in FIGS. 9 and 10, taking the first phase sub-circuit in the first motor control circuit 11 as an example. In the first time sequence, referring to FIG. 9, the second switch K2, the third switch K3, the sixth switch K6, the seventh switch K7 and the first switch tube VT1 are configured to be in a closed state, and the other switches are configured to be in an open state. The current in the first power supply device flows to the sixth switch K6, the first switch tube VT1, the first phase inductor L11, the third switch K3, the battery pack, the second switch K2 and the seventh switch K7 in turn, and then flows back to the first power supply device to form a loop, in which the first phase inductor L11 and the battery pack can be charged.

[0071] When the battery pack is about to complete charging (e.g., 90% complete), or the first phase inductor L11 completes charging, or the continuous charging lasts for a preset time length (e.g., one hour), the second timing is entered. Referring to FIG. 10, in the state of each switch corresponding to the first timing, the sixth switch K6, the seventh switch K7, and the first switch tube VT1 are configured in the open state, and the second switch tube VT2 is configured in the closed state. The current in the first phase inductor L11 after charging flows to the third switch K3, the battery pack, the second switch K2, and the second switch tube VT2 in turn, and then flows back to the first phase inductor L11 to form a loop. In this loop, the stored energy of the first phase inductor L11 can be used to continuously charge the battery pack.

[0072] It should be noted that the application of the switch tube and the phase inductor shown in FIGS. 9-10 is only an example. In other embodiments, the second phase sub-circuit or the third phase sub-circuit in the first motor control circuit 11 and the corresponding phase inductor can also be used to participate in the step-down charging of the battery pack, or even multiple phase sub-circuits can be used simultaneously. That is, multiple phase inductors are charged simultaneously, and multiple phase inductors can also charge the battery simultaneously.

[0073] In some embodiments, the switch combination includes the second switch K2, the third switch K3, the eighth switch K8, and the ninth switch K9. When at least one upper bridge switch tube of the second switch K2, the third switch K3, the eighth switch K8, the ninth switch K9, and the at least one upper bridge switch tube of the three-phase sub-circuit in the first motor control circuit 11 is configured in the closed state, and the first switch K1, the fourth switch K4, the fifth switch K5, the sixth switch K6, and the seventh switch K7 are configured in the open state, the at least one upper bridge switch tube corresponding phase inductor and the battery pack are charged by the second power supply device, and when the eighth switch K8, the ninth switch K9, and the at least one upper bridge switch tube are reconfigured in the open state, and the lower bridge switch tube corresponding to the at least one upper bridge switch tube is configured in the closed state, the battery pack is charged by the phase inductor, so that the battery pack works in the step-down charging mode.

[0074] In some examples, the second power supply device also charges the phase inductor corresponding to a phase sub-circuit in the first motor control circuit 11 during the charging of the battery pack, so as to reduce the charging voltage of the battery pack. And when the second power supply device stops charging the battery pack, the charged phase inductor can also continue to charge the battery pack, so that the battery pack can work in the step-down charging mode.

[0075] The buck charging mode can be divided into two time sequences according to whether the second power supply device is connected. For example, as shown in FIG. 11 and FIG. 10, taking the first phase sub-circuit in the first motor control circuit 11 as an example. In the first time sequence, referring to FIG. 11, the second switch K2, the third switch K3, the eighth switch K8, the ninth switch K9 and the first switch tube VT1 are configured in a closed state, and the other switches are configured in an open state. The current in the second power supply device flows to the eighth switch K8, the first switch tube VT1, the first phase inductor L11, the third switch K3, the battery pack, the second switch K2 and the ninth switch K9 in turn, and then flows back to the second power supply device to form a loop. In the loop, the first phase inductor L11 and the battery pack can be charged.

[0076] When the battery pack is about to complete charging (for example, 90% is completed), or the first phase inductor L11 completes charging, or the continuous charging lasts for a preset time (for example, one hour), the second time sequence is entered. Referring to FIG. 10, in the state of each switch corresponding to the first time sequence, the eighth switch K8, the ninth switch K9 and the first switch tube VT1 are configured in an open state, and the second switch tube VT2 is configured in a closed state. The current in the first phase inductor L11 after charging flows to the third switch K3, the battery pack, the second switch K2 and the second switch tube VT2 in turn, and then flows back to the first phase inductor L11 to form a loop. In the loop, the battery pack can be continuously charged using the energy stored in the first phase inductor L11.

[0077] It should be noted that the application of the switch tube and the phase inductor shown in FIG. 11 and FIG. 10 is only an example. In other embodiments, the second phase sub-circuit or the third phase sub-circuit in the first motor control circuit 11 and the corresponding phase inductor can also be used to participate in the buck charging of the battery pack, and even multiple phase sub-circuits can be used at the same time. That is, multiple phase inductors are charged at the same time, and multiple phase inductors can also simultaneously perform buck charging on the battery.

[0078] In some embodiments, the switch combination includes the second switch K2, the fourth switch K4, the eighth switch K8 and the ninth switch K9. When at least one upper bridge switch tube in the second switch K2, the fourth switch K4, the eighth switch K8, the ninth switch K9 and the three-phase sub-circuit in the third motor control circuit 13 is configured in a closed state, and the first switch K1, the third switch K3, the fifth switch K5, the sixth switch K6 and the seventh switch K7 are configured in an open state, the at least one upper bridge switch tube corresponds to a phase inductor and a battery pack, and the at least one upper bridge switch tube is reconfigured in an open state, and the at least one upper bridge switch tube corresponds to a lower bridge switch tube which is configured in a closed state, the battery pack is charged by the phase inductor, so that the battery pack works in the buck charging mode.

[0079] In some examples, the second power supply device also charges the phase inductor corresponding to the phase sub-circuit in the third motor control circuit 13 during charging of the battery pack, so as to reduce the charging voltage of the battery pack. When the second power supply device stops charging the battery pack, the charged phase inductor can continue to charge the battery pack, so that the battery pack can work in the step-down charging mode.

[0080] The step-down charging mode can be divided into two time sequences according to whether the second power supply device is connected or not. For example, as shown in FIG. 12 and FIG. 13, the first phase sub-circuit in the third motor control circuit 13 is taken as an example for description. In the first time sequence, as shown in FIG. 12, the second switch K2, the fourth switch K4, the eighth switch K8, the ninth switch K9 and the thirteenth switch VT13 are configured in a closed state, and other switches are configured in an open state. The current in the second power supply device flows to the eighth switch K8, the thirteenth switch VT13, the seventh phase inductor L31, the fourth switch K4, the battery pack, the second switch K2 and the ninth switch K9 in turn, and then flows back to the second power supply device to form a loop. In the loop, the seventh phase inductor L31 and the battery pack can be charged.

[0081] When the battery pack is about to complete charging (for example, 90% is completed), or the seventh phase inductor L31 completes charging, or the continuous charging lasts for a preset time length (for example, one hour), the second time sequence is entered. As shown in FIG. 13, in the state of the switches corresponding to the first time sequence, the eighth switch K8, the ninth switch K9 and the thirteenth switch VT13 are configured in an open state, and the fourteenth switch VT14 is configured in a closed state. The current in the charged seventh phase inductor L31 flows to the fourth switch K4, the battery pack, the second switch K2 and the fourteenth switch VT14 in turn, and then flows back to the seventh phase inductor L31 to form a loop. In the loop, the seventh phase inductor L31 can be used to continuously charge the battery pack by using the stored electrical energy.

[0082] It should be noted that the application of the switch and the phase inductor shown in FIG. 12 and FIG. 13 is only an example. In other embodiments, the second phase sub-circuit or the third phase sub-circuit in the third motor control circuit 13 and the corresponding phase inductor can also be used to participate in the step-down charging of the battery pack, and even multiple phase sub-circuits can be used at the same time. That is, multiple phase inductors are charged at the same time, and the multiple phase inductors can also charge the battery at the same time.

[0083] In some embodiments, the switch combination includes the second switch K2, the fourth switch K4, the sixth switch K6, and the seventh switch K7. When at least one upper bridge switch in a three-phase sub-circuit of the second switch K2, the fourth switch K4, the sixth switch K6, the seventh switch K7, and the third motor control circuit 13 is configured to be in a closed state, and the first switch K1, the third switch K3, the fifth switch K5, the eighth switch K8, and the ninth switch K9 are configured to be in an open state, the corresponding phase inductor and the battery pack of the at least one upper bridge switch are charged by the first power supply, and when the sixth switch K6, the seventh switch K7, and the at least one upper bridge switch are reconfigured to be in an open state, and the corresponding lower bridge switch of the at least one upper bridge switch is configured to be in a closed state, the battery pack is charged by the phase inductor to work in a step-down charging mode.

[0084] In some examples, the first power supply also charges the phase inductor corresponding to a one-phase sub-circuit of the third motor control circuit 13 during the charging of the battery pack, so as to reduce the charging voltage of the battery pack. When the first power supply stops charging the battery pack, the charged phase inductor can also continue to charge the battery pack, so that the battery pack can work in the step-down charging mode.

[0085] The step-down charging mode can be divided into two time sequences according to whether the first power supply is connected or not. For example, as shown in FIG. 14 and FIG. 13, the first phase sub-circuit of the third motor control circuit 13 is taken as an example for illustration. In the first time sequence, referring to FIG. 14, the second switch K2, the fourth switch K4, the sixth switch K6, the seventh switch K7, and the thirteenth switch VT13 are configured to be in a closed state, and other switches are configured to be in an open state. The current in the first power supply flows to the sixth switch K6, the thirteenth switch VT13, the seventh phase inductor L31, the fourth switch K4, the battery pack, the second switch K2, and the seventh switch K7 in turn, and then flows back to the first power supply to form a loop. In the loop, the seventh phase inductor L31 and the battery pack can be charged.

[0086] When the battery pack is about to complete charging (for example, 90% is completed), or the seventh phase inductor L31 completes charging, or the continuous charging lasts for a preset time (for example, one hour), the second time sequence is entered. Referring to FIG. 13, in the state of the switches corresponding to the first time sequence, the sixth switch K6, the seventh switch K7, and the thirteenth switch VT13 are configured to be in an open state, and the fourteenth switch VT14 is configured to be in a closed state. The current in the charged seventh phase inductor L31 flows to the fourth switch K4, the battery pack, the second switch K2, and the fourteenth switch VT14 in turn, and then flows back to the seventh phase inductor L31 to form a loop. In the loop, the seventh phase inductor L31 can be used to continuously charge the battery pack.

[0087] It should be noted that the application of the switch tubes and phase inductors shown in FIG. 14 and FIG. 13 is only an example. In other embodiments, the second phase sub-circuit or the third phase sub-circuit in the third motor control circuit 13 and the corresponding phase inductor can also participate in the voltage reduction charging of the battery pack, and even multiple phase sub-circuits can be used at the same time. That is, multiple phase inductors are charged at the same time, and the multiple phase inductors can also charge the battery at the same time.

[0088] In some embodiments, the switch combination includes the second switch K2, the third switch K3, the fifth switch K5, the sixth switch K6, and the seventh switch K7. When the second switch K2, the third switch K3, the fifth switch K5, the sixth switch K6, the seventh switch K7, at least one upper bridge switch tube of the three-phase sub-circuit in the first motor control circuit 11 and at least one lower bridge switch tube of the three-phase sub-circuit in the second motor control circuit 12 are configured to be in a closed state, and the first switch K1, the fourth switch K4, the eighth switch K8, and the ninth switch K9 are configured to be in an open state, the battery pack and the phase inductor corresponding to at least one upper bridge switch tube of the first motor control circuit 11 are charged by the first power supply device, and the phase inductor corresponding to at least one lower bridge switch tube of the second motor control circuit 12 is charged by the battery pack. When the sixth switch K6 and the seventh switch K7 are reconfigured to be in an open state, the first switch K1 is reconfigured to be in a closed state, and the switching states of at least one upper bridge switch tube and the corresponding lower bridge switch tube of the first motor control circuit 11 are swapped, and the switching states of at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit 12 are swapped, the battery pack is charged by the charged phase inductor of the first motor control circuit 11 and the phase inductor of the second motor control circuit 12, so that the battery pack works in the self-heating mode and the voltage reduction charging mode.

[0089] For example, referring to FIG. 9 and FIG. 10, the first power supply device, the first motor control circuit 11, the second switch K2, the third switch K3, the sixth switch K6, and the seventh switch K7 can be used to achieve voltage reduction charging of the battery pack. When the battery pack is in the voltage reduction charging mode, the battery pack can also be self-heated by cooperating the second motor control circuit 12, the fifth switch K5, the first switch K1, and the second switch K2. The self-heating can be described in the corresponding embodiments of FIG. 7 and FIG. 8. To avoid redundancy, it will not be described here.

[0090] In some embodiments, the switch combination includes the second switch K2, the third switch K3, the fifth switch K5, the eighth switch K8 and the ninth switch K9. When the second switch K2, the third switch K3, the fifth switch K5, the eighth switch K8, the ninth switch K9, at least one upper bridge switch tube of the three-phase sub-circuit in the first motor control circuit 11 and at least one lower bridge switch tube of the three-phase sub-circuit in the second motor control circuit 12 are configured to be in the closed state, and the first switch K1, the fourth switch K4, the sixth switch K6 and the seventh switch K7 are configured to be in the open state, the battery pack and the phase inductor corresponding to at least one upper bridge switch tube of the first motor control circuit 11 are charged by the second power supply device, and the phase inductor corresponding to at least one lower bridge switch tube of the second motor control circuit 12 is charged by the battery pack. When the eighth switch K8 and the ninth switch K9 are reconfigured to be in the open state, the first switch K1 is reconfigured to be in the closed state, and the switching states of at least one upper bridge switch tube and the corresponding lower bridge switch tube of the first motor control circuit 11 are swapped, and the switching states of at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit 12 are swapped, the battery pack is charged by the charged phase inductor of the first motor control circuit 11 and the phase inductor of the second motor control circuit 12, so that the battery pack works in the self-heating mode and the step-down charging mode.

[0091] For example, referring to FIGS. 10 and 11, the second power supply device, the first motor control circuit 11, the second switch K2, the third switch K3, the eighth switch K8 and the ninth switch K9 can be used to realize step-down charging of the battery pack. When the battery pack is in the step-down charging mode, the battery pack can also be self-heated by cooperating the second motor control circuit 12, the fifth switch K5, the first switch K1 and the second switch K2. The self-heating can be described in the embodiments corresponding to FIGS. 7 and 8. To avoid redundancy, the description is not repeated here.

[0092] In some embodiments, the switch combination includes the second switch K2, the fourth switch K4, the fifth switch K5, the eighth switch K8 and the ninth switch K9. When the second switch K2, the fourth switch K4, the fifth switch K5, the eighth switch K8, the ninth switch K9, at least one upper bridge switch tube of the three-phase sub-circuit in the third motor control circuit 13 and at least one lower bridge switch tube of the three-phase sub-circuit in the second motor control circuit 12 are configured to be in the closed state, and the first switch K1, the third switch K3, the sixth switch K6 and the seventh switch K7 are configured to be in the open state, the battery pack and the phase inductor corresponding to at least one upper bridge switch tube of the third motor control circuit 13 are charged by the second power supply device, and the phase inductor corresponding to at least one lower bridge switch tube of the second motor control circuit 12 is charged by the battery pack. When the eighth switch K8 and the ninth switch K9 are reconfigured to be in the open state, the first switch K1 is reconfigured to be in the closed state, and the switching states of at least one upper bridge switch tube and the corresponding lower bridge switch tube of the third motor control circuit 13 are swapped, and the switching states of at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit 12 are swapped, the battery pack is charged by the charged phase inductor of the third motor control circuit 13 and the phase inductor of the second motor control circuit 12, so that the battery pack works in the self-heating mode and the step-down charging mode.

[0093] For example, referring to FIGS. 12 and 13, the second power supply device, the third motor control circuit 13, the second switch K2, the fourth switch K4, the eighth switch K8 and the ninth switch K9 can be used to realize step-down charging of the battery pack. When the battery pack is in the step-down charging mode, the battery pack can also be self-heated by cooperating the second motor control circuit 12, the fifth switch K5, the first switch K1 and the second switch K2. The self-heating can be described in the embodiments corresponding to FIGS. 7 and 8. To avoid redundancy, the description is not repeated here.

[0094] In some embodiments, the switch combination includes the second switch K2, the fourth switch K4, the fifth switch K5, the sixth switch K6, and the seventh switch K7. When the second switch K2, the fourth switch K4, the fifth switch K5, the sixth switch K6, the seventh switch K7, at least one upper bridge switch tube of the three-phase sub-circuit in the third motor control circuit 13, and at least one lower bridge switch tube of the three-phase sub-circuit in the second motor control circuit 12 are configured to be in a closed state, and the first switch K1, the third switch K3, the eighth switch K8, and the ninth switch K9 are configured to be in an open state, the first power supply device charges the phase inductor corresponding to at least one upper bridge switch tube of the third motor control circuit 13 and the battery pack, and the battery pack charges the phase inductor corresponding to at least one lower bridge switch tube of the second motor control circuit 12. When the sixth switch K6 and the seventh switch K7 are reconfigured to be in an open state, the first switch K1 is reconfigured to be in a closed state, and the switching states of at least one upper bridge switch tube and the corresponding lower bridge switch tube of the third motor control circuit 13 are swapped, and the switching states of at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit 12 are swapped, the battery pack is charged by the charged phase inductor of the third motor control circuit 13 and the phase inductor of the second motor control circuit 12, so that the battery pack works in the self-heating mode and the step-down charging mode.

[0095] For example, referring to FIG. 13 and FIG. 14, the first power supply device, the third motor control circuit 13, the second switch K2, the fourth switch K4, the sixth switch K6, and the seventh switch K7 can be used to realize step-down charging of the battery pack. When the battery pack is in the step-down charging mode, the battery pack can also be self-heated by cooperating the second motor control circuit 12, the fifth switch K5, the first switch K1, and the second switch K2. The self-heating can be described in the embodiments corresponding to FIG. 7 and FIG. 8, and is not repeated here to avoid redundancy.

[0096] In summary, some embodiments of the present disclosure provide multiple charging modes for the battery pack by using the motor control circuit, which can improve the environmental adaptability of the electric vehicle, reduce the design cost of the electric vehicle, and also ensure the charging efficiency of the battery pack.

[0097] FIG. 15 is a block diagram of an electric vehicle according to some embodiments.

[0098] As shown in FIG. 15, the electric vehicle 100 according to some embodiments of the present disclosure is also provided. The electric vehicle 100 comprises the controller 20 and the battery pack control system 10 of the electric vehicle according to the above embodiments. The controller is connected with the switch module, and is configured to configure the switch state of the switch module, the first motor control circuit, the second motor control circuit and the third motor control circuit, so as to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and the external power supply device, so that the battery pack works in one working mode or two working modes of the self-heating mode, the direct charging mode and the step-down charging mode.

[0099] The electric vehicle according to some embodiments of the present disclosure can improve the environmental adaptability of the electric vehicle, reduce the design cost of the electric vehicle, and ensure the charging efficiency of the battery pack by using the battery pack control system of the electric vehicle according to the above embodiments.

[0100] FIG. 16 is a flowchart of a battery pack control method of an electric vehicle according to some embodiments.

[0101] As shown in FIG. 16, the battery pack control method of an electric vehicle according to some embodiments of the present disclosure is provided. The control method is applied to the electric vehicle according to the above embodiments, and comprises the following steps:

[0102] In step S10, the battery pack control instruction is responded to.

[0103] In step S20, the switch state of the switch module, the first motor control circuit, the second motor control circuit and the third motor control circuit are configured according to the control instruction, so as to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and the external power supply device, so that the battery pack works in one working mode or two working modes of the self-heating mode, the direct charging mode and the step-down charging mode.

[0104] It should be noted that the specific implementation of the battery pack control method of the electric vehicle can refer to the specific implementation of the battery pack control system of the electric vehicle according to the above embodiments, and will not be described here to avoid redundancy.

[0105] In summary, the battery pack control method of the electric vehicle according to some embodiments of the present disclosure can improve the environmental adaptability of the electric vehicle, reduce the design cost of the electric vehicle, and ensure the charging efficiency of the battery pack by providing multiple charging modes to the battery pack by using the motor control circuit.

[0106] It is to be appreciated that at least one of the above described logic or steps, represented in a flow chart or otherwise described herein, for example, can be embodied in executable instructions stored in a computer readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer based system, processor containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions, or a combination thereof. For the purpose of this specification, a "computer readable medium" can be any apparatus that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. The computer readable medium can be, for example but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer readable medium include the following: an electrical connection having one or more wires, a portable computer diskette, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM) or flash memory, an optical fiber, and a portable compact disc read-only memory (CDROM). In addition, the computer readable medium can even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, for example via an optical scanner, then compiled, interpreted, or otherwise processed, and stored in a computer memory in order to be executed.

[0107] It is to be understood that portions of the present disclosure can be implemented with hardware, software, firmware, or a combination thereof. In the above embodiments, a number of steps or methods can be implemented in software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any of the following technologies, known in the art, or a combination thereof, can be used: discrete logic circuitry having logic gates for implementing logic functions upon data signals, application specific integrated circuits having appropriate combinational logic gates, programmable gate arrays (PGA), field programmable gate arrays (FPGA), and the like.

[0108] In the description of the present disclosure, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the present description, the illustrative description of the above terms does not necessarily mean the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0109] In addition, the terms "first", "second", and the like used in the embodiments of the present disclosure are only for the purpose of description and can not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated in the embodiments. Therefore, the features defined with the terms "first", "second" and the like in the embodiments of the present disclosure can explicitly or implicitly indicate that the embodiments include at least one of the features. In the description of the present disclosure, the meaning of the word "a plurality of" is at least two or two or more, for example, two, three, four, and the like, unless otherwise specifically limited in the embodiments.

[0110] In the present disclosure, unless otherwise specifically defined or limited in the embodiments, the terms "mounting", "connecting", "connecting" and "fixing" and the like appearing in the embodiments should be understood in a broad sense, for example, the connection can be a fixed connection, or a detachable connection, or integrated, which can be understood, or can be mechanical connection, electrical connection, etc. Of course, it can also be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements, or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present disclosure can be understood according to the specific implementation situation.

[0111] Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present disclosure, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A battery pack control system of an electric vehicle, wherein, The electric vehicle comprises a first motor control circuit, a second motor control circuit and a third motor control circuit, and the control system comprises: a switch module adapted to be connected between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and an external power supply device, and adapted to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and the external power supply device, so that the battery pack works in one or two working modes of a self-heating mode, a direct charging mode and a step-down charging mode.

2. The battery pack control system of claim 1, wherein, The first motor control circuit, the second motor control circuit and the third motor control circuit each comprise at least one phase sub-circuit, each phase sub-circuit comprising an upper bridge switch tube, a lower bridge switch tube and a phase inductor, the upper bridge switch tube and the lower bridge switch tube being connected in series between the positive and negative terminals of a DC bus, and a node between the upper bridge switch tube and the lower bridge switch tube being connected to one end of the phase inductor, the other end of the phase inductor in each phase sub-circuit of the first motor control circuit being connected and having a first node, the other end of the phase inductor in each phase sub-circuit of the second motor control circuit being connected and having a second node, and the other end of the phase inductor in each phase sub-circuit of the third motor control circuit being connected and having a third node.

3. The battery pack control system of claim 2, wherein, The switch module comprises a plurality of switch combinations, each switch combination comprising a plurality of switches among a first switch, a second switch, a third switch, a fourth switch, a fifth switch, a sixth switch, a seventh switch, an eighth switch and a ninth switch, different switch combinations of the plurality of switch combinations corresponding to different working modes of the battery pack, wherein one end of the first switch is connected to the positive terminal of a first battery module of the battery pack, the other end of the first switch is connected to the positive terminal of the DC bus, one end of the second switch is connected to the negative terminal of a second battery module of the battery pack, the other end of the second switch is connected to the negative terminal of the DC bus, the negative terminal of the first battery module is connected to the positive terminal of the second battery module and has a fourth node, the third switch is connected between the first node and the positive terminal of the first battery module, the fourth switch is connected between the third node and the positive terminal of the first battery module, the fifth switch is connected between the second node and the fourth node, the DC bus is adapted to be connected to a first power supply device of the external power supply device through the sixth switch and the seventh switch, and the DC bus is further adapted to be connected to a second power supply device of the external power supply device through the eighth switch and the ninth switch.

4. The battery pack control system of claim 3, wherein, The electric vehicle further comprises a pre-charging switch, a pre-charging resistor and at least one pre-charging capacitor, the at least one pre-charging capacitor is connected between the positive terminal and the negative terminal of the DC bus, one end of the pre-charging switch is connected with the positive terminal of the DC bus, the other end of the pre-charging switch is connected with one end of the pre-charging resistor, and the other end of the pre-charging resistor is connected with the positive terminal of the first battery module.

5. The battery pack control system of claim 4, wherein, The pre-charging switch and the second switch are configured to be in a closed state before the battery pack works in one or two working modes of the self-heating mode, the direct charging mode and the step-down charging mode, so as to charge the at least one pre-charging capacitor by the battery pack.

6. The battery pack control system of any one of claims 3-5, wherein, At least one of the plurality of switch combinations comprises the first switch, the second switch, the sixth switch and the seventh switch, when the first switch, the second switch, the sixth switch and the seventh switch are configured to be in a closed state, the battery pack is directly charged by the first power supply device, so that the battery pack works in the direct charging mode.

7. The battery pack control system of any one of claims 3-5, wherein, At least one of the plurality of switch combinations comprises the first switch, the second switch, the eighth switch and the ninth switch, when the first switch, the second switch, the eighth switch and the ninth switch are configured to be in a closed state, the battery pack is directly charged by the second power supply device, so that the battery pack works in the direct charging mode.

8. The battery pack control system of any one of claims 3-5, wherein, At least one of the plurality of switch combinations comprises the first switch, the second switch and the fifth switch, when the first switch, the fifth switch and at least one upper bridge switch tube of at least one phase sub-circuit in the second motor control circuit are configured to be in a closed state, and the second switch is configured to be in an open state, the phase inductor corresponding to the at least one upper bridge switch tube is charged by the battery pack, and when the switching states of the first switch and the second switch are replaced, and the switching states of the at least one upper bridge switch tube and the corresponding lower bridge switch tube are replaced, the battery pack is charged by the phase inductor, so that the battery pack works in the self-heating mode.

9. The battery pack control system of any one of claims 3-5, wherein, At least one of the plurality of switch combinations comprises the first switch, the second switch and the fifth switch, when the second switch, the fifth switch and at least one lower bridge switch tube of at least one phase sub-circuit in the second motor control circuit are configured to be in a closed state, and the first switch is configured to be in an open state, the phase inductor corresponding to the at least one lower bridge switch tube is charged by the battery pack, and when the switching states of the first switch and the second switch are replaced, and the switching states of the at least one upper bridge switch tube and the corresponding lower bridge switch tube are replaced, the battery pack is charged by the phase inductor, so that the battery pack works in the self-heating mode.

10. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the first switch, the second switch, the fifth switch, the sixth switch and the seventh switch, when at least one upper bridge switch tube or at least one lower bridge switch tube of at least one phase sub-circuit in the second motor control circuit and the first switch, the second switch, the fifth switch, the sixth switch and the seventh switch are configured to be in a closed state, the battery pack is charged by the first power supply device, and the at least one upper bridge switch tube or the at least one lower bridge switch tube is charged by the battery pack, and when the switching state of the at least one upper bridge switch tube and the corresponding lower bridge switch tube is replaced, or the switching state of the at least one lower bridge switch tube and the corresponding upper bridge switch tube is replaced, the battery pack is charged by the phase inductor, so that the battery pack works in the self-heating mode and the direct charging mode.

11. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the first switch, the second switch, the fifth switch, the eighth switch and the ninth switch, when at least one upper bridge switch tube or at least one lower bridge switch tube of at least one phase sub-circuit in the second motor control circuit and the first switch, the second switch, the fifth switch, the eighth switch and the ninth switch are configured to be in a closed state, the battery pack is charged by the second power supply device, and the at least one upper bridge switch tube or the at least one lower bridge switch tube is charged by the battery pack, and when the switching state of the at least one upper bridge switch tube and the corresponding lower bridge switch tube is replaced, or the switching state of the at least one lower bridge switch tube and the corresponding upper bridge switch tube is replaced, the battery pack is charged by the phase inductor, so that the battery pack works in the self-heating mode and the direct charging mode.

12. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the third switch, the sixth switch and the seventh switch, when the second switch, the third switch, the sixth switch, the seventh switch and at least one upper bridge switch tube of at least one phase sub-circuit in the first motor control circuit are configured to be in a closed state, the at least one upper bridge switch tube and the battery pack are charged by the first power supply device, and when the sixth switch, the seventh switch and the at least one upper bridge switch tube are reconfigured to be in an open state, and the corresponding lower bridge switch tube of the at least one upper bridge switch tube is configured to be in a closed state, the battery pack is charged by the phase inductor, so that the battery pack works in the step-down charging mode.

13. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the third switch, the eighth switch, and the ninth switch, when at least one upper bridge switch corresponding to at least one phase sub-circuit of the second switch, the third switch, the eighth switch, the ninth switch, and the first motor control circuit is configured to be in a closed state, the second power supply device charges the phase inductor corresponding to the at least one upper bridge switch and the battery pack, and when the eighth switch, the ninth switch, and the at least one upper bridge switch are reconfigured to be in an open state, and a lower bridge switch corresponding to the at least one upper bridge switch is configured to be in a closed state, the phase inductor charges the battery pack, so that the battery pack works in the step-down charging mode.

14. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the fourth switch, the eighth switch, and the ninth switch, when at least one upper bridge switch corresponding to at least one phase sub-circuit of the second switch, the fourth switch, the eighth switch, the ninth switch, and the third motor control circuit is configured to be in a closed state, the second power supply device charges the phase inductor corresponding to the at least one upper bridge switch and the battery pack, and when the eighth switch, the ninth switch, and the at least one upper bridge switch are reconfigured to be in an open state, and a lower bridge switch corresponding to the at least one upper bridge switch is configured to be in a closed state, the phase inductor charges the battery pack, so that the battery pack works in the step-down charging mode.

15. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the fourth switch, the sixth switch, and the seventh switch, when at least one upper bridge switch corresponding to at least one phase sub-circuit of the second switch, the fourth switch, the sixth switch, the seventh switch, and the third motor control circuit is configured to be in a closed state, the first power supply device charges the phase inductor corresponding to the at least one upper bridge switch and the battery pack, and when the sixth switch, the seventh switch, and the at least one upper bridge switch are reconfigured to be in an open state, and a lower bridge switch corresponding to the at least one upper bridge switch is configured to be in a closed state, the phase inductor charges the battery pack, so that the battery pack works in the step-down charging mode.

16. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the third switch, the fifth switch, the sixth switch, and the seventh switch, when at least one upper bridge switch tube of at least one phase sub-circuit in the first motor control circuit and at least one lower bridge switch tube of at least one phase sub-circuit in the second motor control circuit are configured to be in a closed state, the first power supply device charges the phase inductor corresponding to the at least one upper bridge switch tube of the first motor control circuit and the battery pack, and the battery pack charges the phase inductor corresponding to the at least one lower bridge switch tube of the second motor control circuit, and when the sixth switch and the seventh switch are reconfigured to be in an open state, the first switch is reconfigured to be in a closed state, and the switching states of the at least one upper bridge switch tube and the corresponding lower bridge switch tube of the first motor control circuit are swapped, and the switching states of the at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit are swapped, the battery pack is charged by the charged phase inductor of the first motor control circuit and the phase inductor of the second motor control circuit, so that the battery pack works in the self-heating mode and the step-down charging mode.

17. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the third switch, the fifth switch, the eighth switch, and the ninth switch, when at least one upper bridge switch tube of at least one phase sub-circuit in the first motor control circuit and at least one lower bridge switch tube of at least one phase sub-circuit in the second motor control circuit are configured to be in a closed state, the second power supply device charges the phase inductor corresponding to the at least one upper bridge switch tube of the first motor control circuit and the battery pack, and the battery pack charges the phase inductor corresponding to the at least one lower bridge switch tube of the second motor control circuit, and when the eighth switch and the ninth switch are reconfigured to be in an open state, the first switch is reconfigured to be in a closed state, and the switching states of the at least one upper bridge switch tube and the corresponding lower bridge switch tube of the first motor control circuit are swapped, and the switching states of the at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit are swapped, the battery pack is charged by the charged phase inductor of the first motor control circuit and the phase inductor of the second motor control circuit, so that the battery pack works in the self-heating mode and the step-down charging mode.

18. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the fourth switch, the fifth switch, the eighth switch, and the ninth switch, when at least one upper bridge switch tube of at least one phase sub-circuit in the third motor control circuit and at least one lower bridge switch tube of at least one phase sub-circuit in the second motor control circuit are configured to be in a closed state, the second power supply device charges the phase inductor corresponding to the at least one upper bridge switch tube of the third motor control circuit and the battery pack, and the battery pack charges the phase inductor corresponding to the at least one lower bridge switch tube of the second motor control circuit, and when the eighth switch and the ninth switch are reconfigured to be in an open state, the first switch is reconfigured to be in a closed state, and the switching states of the at least one upper bridge switch tube and the corresponding lower bridge switch tube of the third motor control circuit are swapped, and the switching states of the at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit are swapped, the battery pack is charged by the charged phase inductor of the third motor control circuit and the phase inductor of the second motor control circuit, so that the battery pack works in the self-heating mode and the step-down charging mode.

19. The battery pack control system of any one of claims 3-5, wherein, At least one of the switch combinations includes the second switch, the fourth switch, the fifth switch, the sixth switch, and the seventh switch, when at least one upper bridge switch tube of at least one phase sub-circuit in the third motor control circuit and at least one lower bridge switch tube of at least one phase sub-circuit in the second motor control circuit are configured to be in a closed state, the first power supply device charges the phase inductor corresponding to the at least one upper bridge switch tube of the third motor control circuit and the battery pack, and the battery pack charges the phase inductor corresponding to the at least one lower bridge switch tube of the second motor control circuit, and when the sixth switch and the seventh switch are reconfigured to be in an open state, the first switch is reconfigured to be in a closed state, and the switching states of the at least one upper bridge switch tube and the corresponding lower bridge switch tube of the third motor control circuit are swapped, and the switching states of the at least one lower bridge switch tube and the corresponding upper bridge switch tube of the second motor control circuit are swapped, the battery pack is charged by the charged phase inductor of the third motor control circuit and the phase inductor of the second motor control circuit, so that the battery pack works in the self-heating mode and the step-down charging mode.

20. An electric vehicle comprising a controller and the battery pack control system of any one of claims 1 to 19, the controller being connected with the switch module for configuring the switch states of the switch module, the first motor control circuit, the second motor control circuit and the third motor control circuit to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and the external power supply device so that the battery pack operates in one or two of the self-heating mode, the direct charging mode and the step-down charging mode.

21. A battery pack control method for an electric vehicle, comprising: responding to a battery pack control instruction; and configuring the switch states of a switch module, a first motor control circuit, a second motor control circuit and a third motor control circuit according to the control instruction to control the connection between the battery pack, the first motor control circuit, the second motor control circuit, the third motor control circuit and an external power supply device so that the battery pack operates in one or two of the self-heating mode, the direct charging mode and the step-down charging mode; wherein the control method is applied to the electric vehicle of claim 20. ​

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