Active discharge circuit, charging and discharging system, and transportation vehicle

Abstract

An active discharge circuit, a charging and discharging system, and a transportation vehicle. The active discharge circuit comprises a first capacitor, an excitation control circuit, and an excitation winding. A first end of the first capacitor is configured to be electrically connected to a first electrode of a battery, and a second end of the first capacitor is configured to be electrically connected to a second electrode of the battery. A first end and a second end of the excitation control circuit are respectively electrically connected to the first end and the second end of the first capacitor. A first end and a second end of the excitation winding are respectively electrically connected to a third end and a fourth end of the excitation control circuit. The excitation control circuit is configured to, by controlling a conduction direction of the excitation control circuit, enable the first capacitor, the excitation control circuit, and the excitation winding to form a discharge loop.

Description

Active bleed circuit, charge and discharge system, vehicle

[0001] This application claims priority to the Chinese patent application No. 202411098030.0, filed on August 9, 2024, the entire content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure relates to the technical field of electric vehicles, in particular to an active bleed circuit, a charge and discharge system, and a vehicle. BACKGROUND

[0003] The high-voltage system of a vehicle generally refers to the high-voltage electrical system in the vehicle, mainly including lithium-ion battery packs, motor controllers, high-voltage cables, and other components. These components collectively constitute the power source of the vehicle, providing high-voltage and high-energy-density electrical power supply. With the development of vehicles, the automotive industry has entered a new stage of large-scale development, and the high-voltage safety of vehicles has gradually become a concern for people purchasing vehicles. SUMMARY

[0004] The present disclosure provides an active bleed circuit, a charge and discharge system, and a vehicle, aiming to simplify the structure of the vehicle bleed system and reduce the cost of the bleed circuit.

[0005] In a first aspect, an active bleed circuit is provided. The active bleed circuit comprises a first capacitor, an excitation control circuit, and an excitation winding. A first end of the first capacitor is configured to be electrically connected to a first pole of a battery, and a second end of the first capacitor is configured to be electrically connected to a second pole of the battery. A first end and a second end of the excitation control circuit are correspondingly electrically connected to the first end and the second end of the first capacitor, respectively. A first end and a second end of the excitation winding are correspondingly electrically connected to a third end and a fourth end of the excitation control circuit, respectively. The excitation control circuit is configured to form a bleed circuit by the first capacitor, the excitation control circuit, and the excitation winding by controlling the conduction direction of the excitation control circuit.

[0006] In a second aspect, a charge and discharge system is provided. The charge and discharge system comprises a battery, a controller, and the active bleed circuit provided in the first aspect. The first capacitor of the active bleed circuit is connected in parallel across the battery. The controller is electrically connected to the excitation control circuit of the active bleed circuit. The controller is configured to control the excitation control circuit to form a bleed circuit by the active bleed circuit, and to bleed the electrical energy stored in the first capacitor.

[0007] In a third aspect, a vehicle is provided, comprising the charge and discharge system provided in the second aspect. BRIEF DESCRIPTION OF DRAWINGS

[0008] FIG. 1 is a circuit structure topology diagram of an active bleed circuit according to some embodiments;

[0009] Figure 2 is a current flow diagram for the active bleed circuit of Figure 1 when forming a first bleed loop;

[0010] Figure 3 is a current flow diagram for the active bleed circuit of Figure 1 when forming a second bleed loop;

[0011] Figure 4 is another current flow diagram for the active bleed circuit of Figure 1 when forming a second bleed loop;

[0012] Figure 5 is a current flow diagram for the active bleed circuit of Figure 1 when forming a first bleed loop and a third bleed loop;

[0013] Figure 6 is a current flow diagram for the active bleed circuit of Figure 1 when forming a first bleed loop and a fourth bleed loop;

[0014] Figure 7 is a circuit configuration topology diagram for an active bleed circuit according to further embodiments;

[0015] Figure 8 is a current flow diagram for the active bleed circuit of Figure 7 when forming a first bleed loop and a fifth bleed loop;

[0016] Figure 9 is a current flow diagram for the active bleed circuit of Figure 7 when forming a second bleed loop;

[0017] Figure 10 is another current flow diagram for the active bleed circuit of Figure 7 when forming a second bleed loop;

[0018] Figure 11 is a current flow diagram for the active bleed circuit of Figure 7 when forming a first bleed loop and a third bleed loop;

[0019] Figure 12 is a current flow diagram for the active bleed circuit of Figure 7 when forming a first bleed loop and a fourth bleed loop;

[0020] Figure 13 is a circuit configuration topology diagram for an active bleed circuit according to yet further embodiments;

[0021] Figure 14 is a block diagram of a vehicle according to some embodiments;

[0022] Figure 15 is a block diagram of a charge and discharge system according to some embodiments. DETAILED DESCRIPTION

[0023] The technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments of the present disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present disclosure.

[0024] In the description of the disclosure, it needs to be understood that the terms "upper", "lower", "left", "right", "front", "back", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or relative position relationship shown in the drawings, and are only for the convenience of describing the disclosure and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the disclosure. Unless otherwise specified, the above orientation description can be flexibly arranged in the actual application process under the condition of meeting the relative position relationship shown in the drawings.

[0025] The terms "first", "second", "third", etc. are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the disclosure, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0026] In the description of the disclosure, it needs to be noted that, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "communicating" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrally connected. It can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those skilled in the art, the meaning of the above terms in the disclosure can be understood according to the situation.

[0027] In the embodiments of the disclosure, the terms "comprising", "containing" or any other variants thereof are intended to cover non-exclusive containing, so that the process, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, article or device. Without more limitation, the element defined by the sentence "including a…" does not exclude the existence of other identical elements in the process, article or device including the element.

[0028] In the embodiments of the disclosure, the words "exemplary" or "for example" are used to mean serving as an example, instance, or illustration. Any embodiment or design presented as "exemplary" or "for example" in the embodiments of the disclosure should not be construed as being more preferred or advantageous than other embodiments or design solutions. Rather, the use of "exemplary" or "for example" is intended to present concepts in a concrete manner. It is to be understood that one or more embodiments or design solutions described as "exemplary" or "for example" can include other embodiments or design solutions not specifically presented or described as such.

[0029] In the description of the specification, the features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0030] Automobile safety problems occur frequently, and high-voltage safety of the automobile gradually becomes a concern for people when purchasing the automobile. In the related technology, a special discharge circuit is usually designed to realize active discharge of the direct-current high-voltage loop, which not only increases the complexity of the circuit structure, but also greatly increases the cost of the vehicle.

[0031] Based on this, some embodiments of the present disclosure provide a vehicle, as shown in FIG. 14, which includes a charge-discharge system 100.

[0032] The vehicle 1000 described in some embodiments of the present disclosure includes but is not limited to a vehicle, an airplane, or a ship, and the like, and has a charge-discharge system in the vehicle. The following describes some embodiments of the present disclosure by taking the vehicle as an example.

[0033] In some embodiments, as shown in FIG. 15, the charge-discharge system 100 includes an active discharge circuit 110, a battery 120, and a controller 130. The active discharge circuit 110 includes a first capacitor C1, an excitation control circuit, and an excitation winding.

[0034] For example, the first capacitor C1 of the active discharge circuit is connected in parallel across the battery. A first end of the first capacitor C1 is configured to be electrically connected to a first pole of the battery, and a second end of the first capacitor C1 is configured to be electrically connected to a second pole of the battery.

[0035] For example, the first end of the first capacitor C1 is electrically connected to the first pole of the battery, and the second end of the first capacitor C1 is electrically connected to the second pole of the battery.

[0036] For example, as shown in FIG. 1, the charge-discharge system further includes at least one of a third switch module K3 or a fourth switch module K4. The third switch module K3 is electrically connected between the first pole of the battery and the first end of the first capacitor C1. The fourth switch module K4 is electrically connected between the second pole of the battery and the second end of the first capacitor C1.

[0037] The first end and the second end of the excitation control circuit are electrically connected to the two ends of the first capacitor C1. In the case where the charge-discharge system further includes the third switch module K3, the second end of the excitation control circuit is electrically connected to the common connection end of the third switch module K3 and the first capacitor C1; in the case where the charge-discharge system further includes the fourth switch module K4, the first end of the excitation control circuit is electrically connected to the common connection end of the fourth switch module K4 and the first capacitor C1.

[0038] By controlling at least one of the third switch module K3 or the fourth switch module K4 to be closed or opened, the on-off between the first capacitor C1 and the battery can be controlled.

[0039] In this way, when the first capacitor C1 is discharged, at least one of the third switch module K3 or the fourth switch module K4 is turned off, so that the battery is disconnected from the first capacitor C1, thereby avoiding discharging the battery during the discharge of the first capacitor C1.

[0040] In some embodiments, in the active discharge circuit, the first end and the second end of the excitation control circuit are respectively electrically connected to the first end and the second end of the first capacitor C1. For example, the first end of the first capacitor C1 is electrically connected to the first end of the excitation control circuit, and the second end of the first capacitor C1 is electrically connected to the second end of the excitation control circuit.

[0041] In some embodiments, in the active discharge circuit, the first end and the second end of the excitation winding are respectively electrically connected to the third end and the fourth end of the excitation control circuit. For example, the first end of the excitation winding is electrically connected to the third end of the excitation control circuit, and the second end of the excitation winding is electrically connected to the fourth end of the excitation control circuit.

[0042] In some embodiments, the controller of the charge and discharge system is electrically connected to the excitation control circuit of the active discharge circuit. The controller is configured to control the excitation control circuit to form a discharge loop with the active discharge circuit to discharge the electrical energy stored in the first capacitor C1.

[0043] The battery is configured to provide electrical energy for the load. The load can be an electric motor in a vehicle. The electric motor can be a direct current motor or an alternating current motor.

[0044] For example, the vehicle can be configured with at least one of different types of electric motors such as permanent magnet synchronous motors, asynchronous motors, and excitation motors. Each electric motor can be correspondingly configured with an electric motor control circuit, and the corresponding electric motor is controlled by controlling the electric motor control circuit. The electric motor control circuit can be an inverter.

[0045] In some embodiments, the vehicle includes at least one first motor and at least one first inverter corresponding to the first electrode. The first motor can be a permanent magnet synchronous motor, an asynchronous motor, an excitation motor, or other types of electrodes. The first motor includes a first winding coil, and the first inverter can be an electric motor control circuit corresponding to the first motor.

[0046] In some embodiments, as shown in FIG. 1, the first pole of the first inverter is electrically connected to the first pole of the battery, the second pole of the first inverter is electrically connected to the second pole of the battery, and the third pole of the first inverter is electrically connected to the first end of the first electrode.

[0047] When the vehicle starts, the third switch module K3 and the fourth switch module K4 are closed when the battery supplies power to the first motor through the first inverter, and the battery charges the first capacitor C1 while supplying power to the first motor.

[0048] When it is needed to discharge the first capacitor C1, for example, when the vehicle needs to be powered off after parking, the first capacitor C1 can be discharged by the field winding.

[0049] Based on this, in some embodiments, as shown in FIGS. 2 to 4, the field control circuit is configured to form a discharge loop by the first capacitor C1, the field control circuit and the field winding by controlling the conduction direction of the field control circuit.

[0050] The field motor includes a field winding, and in the active discharge circuit provided by some embodiments of the present disclosure, the field winding can be the field winding of the field motor carried by the vehicle. In this way, the discharge of the bus capacitor in the vehicle can be realized by the field winding of the field motor owned by the vehicle, without the need to add a structure for discharging the bus capacitor in the vehicle, thereby simplifying the vehicle structure and reducing the cost of the vehicle.

[0051] The motor in some embodiments of the present disclosure can be neutral line leading or phase line leading. For example, as shown in FIG. 1, the motor (for example, the first electrode shown in FIG. 1) is three-phase four-wire, and the motor is connected to the second switch module K2 through the neutral line N (the first neutral point N1 shown in FIG. 1 is a node on the neutral line N of the first motor).

[0052] Alternatively, the motor (for example, the first electrode shown in FIG. 1) is phase line leading, and the motor is three-phase three-wire, and the second switch module K2 in FIG. 1 is connected to any one of the first winding coils L1-L3 of the first motor.

[0053] In some embodiments, as shown in FIG. 2, the field control circuit is configured to form a first discharge loop by the first end and the third end of the field control circuit being conducted, and the second end and the fourth end of the field control circuit being conducted, so that the current flows from the first end of the first capacitor C1, through the first end to the third end of the field control circuit, the field winding, the fourth end to the second end of the field control circuit, and the second end of the first capacitor C1 in sequence.

[0054] In some application scenarios, for example, in the process of powering off the vehicle, the first capacitor C1 needs to be discharged, as shown in FIG. 2, the first capacitor C1 is disconnected from the battery. The electrical energy stored in the first capacitor C1 is released to the field winding, thereby realizing the discharge of the first capacitor C1. The discharge process is simple and stable, and the discharge of the first capacitor C1 can be realized safely and quickly.

[0055] In the related art, the first capacitor C1 is discharged by setting a discharge resistor. The additional discharge circuit and the corresponding connection harness will bring additional cost, and the circuit structure will be more complex. In some embodiments of the present disclosure, the discharge of the first capacitor C1 is realized by the self-owned field winding, without the need to additionally increase the discharge resistor, which can reduce the cost of the active discharge circuit and simplify the structure of the discharge circuit.

[0056] In the related art, the bus capacitor is discharged by the first winding coil of the first motor. The control mode of id≠0 and Iq=0 (id and iq are the currents of the first winding coil of the first motor in the d-q axis coordinate system) is adopted. Referring to FIG. 1, the first capacitor C1 can be discharged by controlling the current flowing through the first winding coil and the first inverter. In this case, when the motor zero position has a deviation, the motor will have torque fluctuation, and even cause gear abnormal sound and other noises.

[0057] In some embodiments of the present disclosure, the active discharge is realized by the field winding. Even if the motor zero position is inaccurate or the zero position is unknown, it will not cause the motor torque fluctuation to appear gear noise.

[0058] In some embodiments, as shown in FIG. 3, the field control circuit is further configured to: turn on the first end and the third end of the field control circuit, and turn on the first end and the fourth end of the field control circuit, so that the current flows from the second end of the field winding, sequentially through the fourth end to the first end of the field control circuit, the third end to the first end of the field control circuit, to form a second discharge loop.

[0059] In some embodiments, as shown in FIG. 4, the field control circuit is further configured to: turn on the second end and the third end of the field control circuit, and turn on the second end and the fourth end of the field control circuit, so that the current flows from the second end of the field winding, sequentially through the fourth end of the field control circuit, the second end of the field control circuit, the third end of the field control circuit, to the first end of the field winding, to form a second discharge loop.

[0060] In some embodiments, as shown in FIGS. 2, 3 and 4, during the process of discharging the first capacitor C1, the active discharge circuit includes switching between the first stage and the second stage. The field control circuit is configured to form part of the first discharge loop in the first stage, and form part of the second discharge loop in the second stage.

[0061] In some embodiments of the present disclosure, when the first capacitor C1 needs to be discharged, the current flowing through the field winding can be controlled by controlling the conduction direction of the field control circuit to discharge the first capacitor C1. The discharge process is simple and stable, and the bus capacitor can be safely and quickly discharged.

[0062] The excitation winding can be an excitation winding of any motor with electric excitation in the vehicle, so that the discharge of the bus capacitor can be achieved by using the self-structure of the vehicle, without the need to additionally set a discharge resistor or the like structure, thereby reducing the cost of the vehicle.

[0063] In some embodiments, as shown in FIG. 1, the third pole of the first inverter is electrically connected to the first end of the first winding coil. When charging the battery, or discharging the battery, the third switch module K3 and the fifth switch module K5 are closed, the second pole of the first inverter is also electrically connected to the second pole of the charge-discharge port, and the second pole of the battery is also electrically connected to the second pole of the charge-discharge port.

[0064] In the case of charging the battery, or discharging the battery to the outside, the charge-discharge port can be connected to an external power source or an energy storage device. For example, a charging pile or an energy storage power source (such as a mobile charging vehicle, an energy storage device, and a battery in another vehicle, etc.).

[0065] Based on this, in some embodiments, as shown in FIG. 5, the active discharge circuit further includes a second capacitor C2, and the charge-discharge system further includes a charge-discharge port. The second capacitor C2 of the active discharge circuit is connected in parallel between the two ends of the charge-discharge port. For example, the first end of the second capacitor C2 is electrically connected to the first end of the charge-discharge port, and the second end of the second capacitor C2 is electrically connected to the second end of the charge-discharge port.

[0066] In some embodiments, as shown in FIG. 5, the charge-discharge system further includes a fifth switch module K5, which is electrically connected between the second end of the second capacitor C2 and the second pole of the charge-discharge port.

[0067] By controlling the closing or opening of the fifth switch module K5, the on-off of the second capacitor C2 and the charge-discharge port can be controlled.

[0068] In some embodiments, as shown in FIG. 5, the active discharge circuit further includes a first inverter and a first motor. The first end of the first motor is electrically connected to the third pole of the first inverter.

[0069] The first pole and the second pole of the first inverter are electrically connected to the first end and the second end of the first capacitor C1, respectively. For example, the first pole of the first inverter is electrically connected to the first end of the first capacitor C1, and the second pole of the first inverter is electrically connected to the second end of the second capacitor C2.

[0070] For example, the second end of the second capacitor C2 is also electrically connected to the second end of the first capacitor C1. The second capacitor C2 is configured to be connected in parallel between the two ends of the charge-discharge port when the battery is electrically connected to the charge-discharge port.

[0071] In the case of charging the battery or discharging the battery, the first end and the second end of the second capacitor C2 are respectively electrically connected with the first pole and the second pole of the charging and discharging port. For example, in the case of charging the battery or discharging the battery, the first end of the second capacitor C2 is electrically connected with the first pole of the charging and discharging port, and the second end of the second capacitor C2 is electrically connected with the second pole of the charging and discharging port.

[0072] In some embodiments, as shown in FIG. 5, the active bleeding circuit further includes a first switch module K1 and a second switch module K2. The first end of the first capacitor C1 is electrically connected with the first end of the second capacitor C2 through the first switch module K1. The second end of the first motor is electrically connected with the first end of the second capacitor C2 through the second switch module K2.

[0073] In the case of charging the battery, for example, the external power supply is connected to the charging and discharging port to charge the battery. During the process of charging the battery, the voltage provided by the charging and discharging port also charges the first capacitor C1 and the second capacitor C2. After the charging is completed, the first capacitor C1 and the second capacitor C2 need to be discharged.

[0074] In some embodiments, as shown in FIG. 5, in the case that the voltage of the second capacitor C2 is greater than zero, and the absolute value of the voltage difference between the second capacitor C2 and the first capacitor C1 is less than a set threshold, the first switch module K1 is configured to be closed, and the second switch module K2 is configured to be opened, so that the current forms a third bleeding loop from the first end of the second capacitor C2, through the first end to the third end of the excitation control circuit, the excitation winding, the fourth end to the second end of the excitation control circuit, and the second end of the second capacitor C2.

[0075] In the case of discharging the battery, for example, the external power supply is connected to the charging and discharging port to discharge the battery. During the process of discharging the battery, the voltage provided by the charging and discharging port also discharges the first capacitor C1 and the second capacitor C2. After the discharging is completed, the first capacitor C1 and the second capacitor C2 need to be charged.

[0076] In this case, as shown in FIG. 5, the third switch module K3, the fourth switch module K4 and the fifth switch module K5 are opened, and the first switch module K1 is closed. In the first stage, the first bleeding loop and the third bleeding loop can be formed at the same time.

[0077] In this application scenario, the second bleeding loop formed in the second stage is described in the foregoing description of FIG. 3 and FIG. 4, which will not be repeated here.

[0078] In some embodiments, as shown in FIG. 6, when the voltage of the second capacitor C2 is greater than zero and less than the voltage of the first capacitor C1, and the voltage difference between the first capacitor C1 and the second capacitor C2 is greater than or equal to a set threshold, the first switch module K1 is configured to be open, and the second switch module K2 is configured to be closed, so that the current forms a fourth discharge loop from the first end of the second capacitor C2, through the first motor, the first inverter, the first end to the third end of the excitation control circuit, the excitation winding, the fourth end to the second end of the excitation control circuit, and the second end of the second capacitor C2.

[0079] In the case where the first capacitor C1 and the second capacitor C2 need to be discharged, for example, in the case where the external power source boosts the battery to charge, after charging, the voltage of the first capacitor C1 is greater than the voltage of the second capacitor C2, and the difference between the first capacitor C1 and the second capacitor C2 is large. In this case, closing the first switch module K1 will easily cause current impact when connecting the second capacitor C2 and the first capacitor C1 in parallel, resulting in problems such as contact burning or even sintering of the fifth switch module K5.

[0080] In this case, the first switch module K1 is open, and the second switch module K2 is turned on, so that the excitation control circuit forms part of the fourth discharge loop. In this way, the first capacitor C1 and the second capacitor C2 with a large voltage difference are not directly connected in parallel, avoiding the problem of directly connecting the first capacitor C1 and the second capacitor C2 under a large voltage difference, which can easily cause current impact when the first switch module K1 is turned on, resulting in problems such as contact burning or even sintering of the first switch module K1.

[0081] In some embodiments, as shown in FIG. 4, FIG. 5 and FIG. 6, during the discharge of the second capacitor C2, the active discharge circuit includes switching between the first stage and the second stage. The excitation control circuit is configured to form part of the third discharge loop or part of the fourth discharge loop in the first stage, and form part of the second discharge loop in the second stage.

[0082] The second capacitor C2 can be discharged at the same time as the first capacitor C1, in which case at least part of the third discharge loop or the fourth discharge loop formed in the first stage is the same as the first discharge loop; in the second discharge loop formed in the second stage, both the electrical energy provided by the first capacitor C1 and the electrical energy provided by the second capacitor C2 are included.

[0083] The second discharge loop formed in the second stage is described above with reference to FIG. 3 and FIG. 4, and will not be described again here.

[0084] The following describes the first stage of the discharge of the second capacitor C2 to form the third discharge loop or the fourth discharge loop.

[0085] Based on the above, in some embodiments of the present disclosure, in this case, as shown in FIG. 6, when the voltage difference between the first capacitor C1 and the second capacitor C2 is large, the first switch module K1, the third switch module K3, the fourth switch module K4 and the fifth switch module K5 are controlled to be open, and the second switch module K2 is controlled to be closed. The first end of the second capacitor C2 is electrically connected to the first end of the first capacitor C1 through the first winding coil and the first inverter. In this way, the current between the first capacitor C1 and the second capacitor C2 is reduced through the first winding coil of the first motor, so that the second switch module K2 is not affected by a large current.

[0086] For example, as shown in FIG. 1, the first winding coil can include a first coil L1, a second coil L2 and a third coil L3. Of course, the first winding coil can also include more or fewer coils.

[0087] In this application scenario, the second discharge loop formed in the second stage is described above with reference to FIGS. 3 and 4, and will not be described again here.

[0088] In some embodiments of the present disclosure, the second capacitor C2 is actively discharged through the field winding, without the need to additionally increase the discharge resistance, which can reduce the cost of the active discharge circuit and simplify the structure of the discharge circuit. Moreover, the first capacitor C1 and the second capacitor C2 can be discharged through the field winding at the same time, which simplifies the discharge circuit structure and improves the discharge efficiency.

[0089] Based on this, in some embodiments, the charge and discharge system further includes a fifth switch module K5 electrically connected between the second end of the second capacitor C2 and the negative electrode of the external power supply.

[0090] By controlling the fifth switch module K5 to be closed or open, the connection between the second capacitor C2 and the external power supply can be controlled. In this way, in the case of charging the battery or discharging the battery to the outside, the fifth switch module K5 can be opened first in the electrical connection matching stage before the external power supply and the battery are electrically connected for power transmission, and the fifth switch module K5 is closed after the matching of the external power supply and the battery is completed, so as to realize the electrical connection between the external power supply and the battery. Thus, the problem of current shock caused by directly connecting the external power supply and the battery under the condition of voltage mismatch or other abnormal conditions can be avoided.

[0091] In some embodiments, as shown in FIG. 6, the first inverter includes a plurality of first bridge arms. The two ends of each first bridge arm are electrically connected to the first pole and the second pole of the first inverter, respectively. Each first bridge arm includes a first switch element and a second switch element, and the common connection end of the first switch element and the second switch element serves as a third pole of the first inverter.

[0092] The first switch element includes a first transistor VT1 / VT3 / VT5 and a first diode VD1 / VD3 / VD5, and the second switch element includes a second transistor VT2 / VT4 / VT6 and a second diode VD2 / VD4 / VD6. The first transistor VT1 / VT3 / VT5 and the first diode VD1 / VD3 / VD5 are connected in parallel between a third pole of the first inverter and a third pole of the first inverter, and the second transistor VT2 / VT4 / VT6 and the second diode VD2 / VD4 / VD6 are connected in parallel between a third pole of the first inverter and a third pole of the first inverter.

[0093] The first motor includes a plurality of groups of first winding coils, and a first end of each group of first winding coils is electrically connected to a third pole of the first inverter. In the case of charging the battery or discharging the battery, a second end of each group of first winding coils is electrically connected to a first pole of the charge-discharge port.

[0094] In some embodiments, as shown in FIG. 6, each group of first winding coils L is electrically connected between a third pole of the first inverter and the second switch module K2.

[0095] By controlling the on-off of the switch elements (transistors and diodes in at least one of the first switch element or the second switch element) of the excitation control circuit, the discharge of the second capacitor C2 is achieved by controlling the current flowing through the excitation winding.

[0096] In some embodiments, as shown in FIG. 6, in the case of forming a fourth discharge loop, the first transistor VT1 / VT3 / VT5 and the second transistor VT2 / VT4 / VT6 of at least one phase bridge arm of the first inverter are configured to be turned off, the first diode VD1 / VD3 / VD5 is turned on, and the second diode VD2 / VD4 / VD6 is turned off.

[0097] For example, as shown in FIG. 6, the first transistor VT1 and the first diode VD1 constitute the first switch element of a phase bridge arm of the first inverter, and the second transistor VT2 and the second diode VD2 constitute the second switch element of a phase bridge arm of the first inverter.

[0098] As shown in FIG. 6, the first transistor VT3 and the first diode VD3 constitute the first switch element of a phase bridge arm of the first inverter, and the second transistor VT4 and the second diode VD4 constitute the second switch element of a phase bridge arm of the first inverter.

[0099] As shown in FIG. 6, the first transistor VT5 and the first diode VD5 constitute the first switch element of a phase bridge arm of the first inverter, and the second transistor VT6 and the second diode VD6 constitute the second switch element of a phase bridge arm of the first inverter.

[0100] In the case of forming the fourth discharge loop, the first end of the second capacitor C2 and the first end of the first capacitor C1 can be electrically connected through the first diode of the first switching element of at least one phase bridge arm of the first inverter.

[0101] For example, as shown in FIG. 6, in the case where the first inverter includes three phase bridge arms, the first end of the second capacitor C2 and the first end of the first capacitor C1 can be electrically connected through one or more (two or more) of the first diode VD1, the first diode VD3 and the first diode VD5.

[0102] Based on the above, in the case where the vehicle is configured with multiple (two or more) motors, at least one winding coil of a motor and the motor control circuit corresponding thereto (for example, the first winding coil and the first inverter shown in FIG. 7) can participate in the charging and discharging process between the battery and the external power supply, and at least one motor and the motor control circuit corresponding thereto (for example, the second winding coil and the second inverter shown in FIG. 7) do not participate in the charging and discharging process between the battery and the external power supply.

[0103] In some embodiments, as shown in FIG. 7, the active discharge circuit further includes a third bus capacitor C3, a second inverter and a second motor. The first end and the second end of the third bus capacitor C3 are respectively electrically connected to the first pole and the second pole of the battery. The first pole and the second pole of the second inverter are respectively electrically connected to the two ends of the second capacitor C2. The first end and the second end of the third bus capacitor C3 are respectively electrically connected to the first end and the second end of the excitation control circuit.

[0104] For example, the second inverter includes multiple phase second bridge arms, and the two ends of each phase second bridge arm are respectively electrically connected to the first pole and the second pole of the second inverter. Each phase second bridge arm includes a third switching element and a fourth switching element, and the common connection end of the third switching element and the fourth switching element serves as a third pole of the second inverter.

[0105] The third switching element includes a fifth transistor VT21 / VT23 / VT25 and a seventh diode VD21 / VD23 / VD25, and the fourth switching element includes a sixth transistor VT22 / VT24 / VT26 and an eighth diode VD22 / VD24 / VD26. The fifth transistor VT21 / VT23 / VT25 and the seventh diode VD21 / VD23 / VD25 are connected in parallel between the first pole and a third pole of the second inverter, and the sixth transistor VT22 / VT24 / VT26 and the eighth diode VD22 / VD24 / VD26 are connected in parallel between the second pole and a third pole of the second inverter.

[0106] The second motor includes multiple groups of second winding coils, and the first end of each group of second winding coils is electrically connected to a third pole of the second inverter.

[0107] In some embodiments, the battery comprises: a first sub-battery E1 and a second sub-battery E2 connected in series, the first sub-battery E1 and the second sub-battery E2 being electrically connected between the first pole and the second pole of the battery. The first end of the second motor is electrically connected to the third pole of the second inverter, and the second end of the second motor is electrically connected to the common connection end of the first sub-battery E1 and the second sub-battery E2.

[0108] For example, the charge and discharge system further comprises: a sixth switch module K6, one end of the sixth switch module K6 being electrically connected to the common connection end of the first sub-battery E1 and the second sub-battery E2, and the other end of the sixth switch module K6 being electrically connected to the second end of the second winding coil.

[0109] In some embodiments, as shown in FIG. 6, each group of second winding coils is electrically connected between one third pole of the second inverter and the sixth switch module K6.

[0110] In some embodiments, as shown in FIG. 8, the excitation control circuit is configured to: by turning on the first end and the third end of the excitation control circuit, and turning on the second end and the fourth end of the excitation control circuit, the current flows from the first end of the third bus capacitor C3, through the first end of the excitation control circuit, the third end of the excitation control circuit, the excitation winding, the fourth end of the excitation control circuit, the second end of the excitation control circuit, to the second end of the third bus capacitor C3, to form a fifth discharge loop.

[0111] By controlling the conduction direction of the excitation control circuit, the excitation winding flows through the current to discharge the third bus capacitor C3, the discharge process is simple, the discharge process is stable, and the discharge of the bus capacitor can be safely and quickly realized.

[0112] As shown in FIGS. 8, 9 and 10, during the process of discharging the third bus capacitor C3, the active discharge circuit includes switching between the first stage and the second stage. The excitation control circuit is configured to form part of the fifth discharge loop in the first stage of discharging the third bus capacitor C3, and form part of the second discharge loop in the second stage of discharging the third bus capacitor C3.

[0113] The third bus capacitor C3 can be discharged at the same time as the first capacitor C1, in which case at least part of the fifth discharge loop formed in the first stage is the same as the first discharge loop; in the second discharge loop formed in the second stage, both the electrical energy provided by the first capacitor C1 and the electrical energy provided by the third bus capacitor C3 are included.

[0114] And, the third bus capacitor C3, the second capacitor C2 and the first capacitor C1 can be discharged at the same time, on this basis, referring to FIG. 11 and FIG. 12, in the first stage, the first discharge loop, the fifth discharge loop and the third discharge loop or the fourth discharge loop can be formed at the same time; in the second stage, the second discharge loop formed includes the electric energy provided by the first capacitor C1 and the electric energy provided by the second capacitor C2 and the third bus capacitor C3.

[0115] The second discharge loop formed in the second stage is described with reference to FIG. 9 and FIG. 10, and the description of FIG. 3 and FIG. 4 above, which will not be repeated here.

[0116] Based on this, in some embodiments, referring to FIG. 12, the charge and discharge system further includes at least one of the third switch module K3 or the fourth switch module K4, the third switch module K3 is electrically connected between the second pole of the battery and the second end of the third bus capacitor C3, and the fourth switch module K4 is electrically connected between the first pole of the battery and the first end of the third bus capacitor C3.

[0117] The first end and the second end of the excitation control circuit are electrically connected to the two ends of the third bus capacitor C3. In the case that the charge and discharge system further includes the third switch module K3, the second end of the excitation control circuit is electrically connected to the common connection end of the third switch module K3 and the third bus capacitor C3; in the case that the charge and discharge system further includes the fourth switch module K4, the first end of the excitation control circuit is electrically connected to the common connection end of the fourth switch module K4 and the third bus capacitor C3.

[0118] By controlling at least one of the third switch module K3 or the fourth switch module K4 to be closed or opened, the connection and disconnection between the third bus capacitor C3 and the battery can be controlled. In this way, when discharging the third bus capacitor C3, at least one of the third switch module K3 or the fourth switch module K4 is opened, so that the battery is disconnected from the third bus capacitor C3, thereby avoiding discharging the battery during discharging the third bus capacitor C3.

[0119] In some embodiments, as shown in FIG. 12, the active discharge circuit further includes an inductor L, the first end of the inductor L is electrically connected to the first end of the first capacitor C1, and the second end of the inductor L is electrically connected to the first pole of the second inverter.

[0120] By setting the inductor L, the electric energy provided by the battery to the second electric drive assembly can be stored, and the inductor L can also transmit the electric energy stored by itself to the battery, so as to realize the heating of the battery through the discharge and charge cycle of the battery.

[0121] In some embodiments, as shown in FIG. 8, the excitation control circuit comprises a third transistor VT7, a fourth transistor VT10, a third diode VD7, a fourth diode VD10, a fifth diode VD8 and a sixth diode VD9. The third transistor VT7 and the third diode VD7 are connected in parallel between the first end and the third end of the excitation control circuit. The fourth transistor VT10 and the fourth diode VD10 are connected in parallel between the second end and the fourth end of the excitation control circuit. The fifth diode VD8 is electrically connected between the second end and the third end of the excitation control circuit. The sixth diode VD9 is electrically connected between the first end and the fourth end of the excitation control circuit.

[0122] By controlling the conduction direction of each transistor and diode in the excitation control circuit, thereby controlling the direction of current flow through the excitation control circuit, the control method is simpler.

[0123] For example, as shown in FIG. 8, the first end and the third end of the excitation control circuit are turned on, the second end and the fourth end of the excitation control circuit are turned on, which includes: the third transistor VT7 and the fourth transistor VT10 are turned on, and the third diode VD7, the fourth diode VD10, the fifth diode VD8 and the sixth diode VD9 are turned off.

[0124] For example, as shown in FIG. 9, the first end and the third end of the excitation control circuit are turned on, and the first end and the fourth end of the excitation control circuit are turned on, which includes: the third transistor VT7 is turned on, the fourth transistor VT10 is turned off, and the third diode VD7, the fourth diode VD10 and the fifth diode VD8 are turned off, and the sixth diode VD9 is turned on.

[0125] For example, as shown in FIG. 10, the second end and the third end of the excitation control circuit are turned on, and the second end and the fourth end of the excitation control circuit are turned on, which includes: the third transistor VT7 is turned off, the fourth transistor VT10 is turned on, and the third diode VD7, the fourth diode VD10 and the sixth diode VD9 are turned off, and the fifth diode VD8 is turned on.

[0126] In some embodiments, as shown in FIG. 13, the active bleeding circuit comprises a plurality of first capacitors C1, a plurality of second capacitors C2, a plurality of first inverters, a plurality of first motors, a plurality of first switch modules K1 and a plurality of second switch modules K2.

[0127] The first end and the second end of the excitation control circuit are respectively electrically connected to the two ends of each first capacitor C1.

[0128] The first end of each second capacitor C2 is electrically connected to the first end of one first capacitor C1 through one first switch module K1, and the second end of each second capacitor C2 is electrically connected to the second end of one first capacitor C1.

[0129] The first pole and the second pole of each first inverter are electrically connected to two ends of a first capacitor C1 respectively.

[0130] The first end of each first motor is electrically connected to a third pole of a first inverter, and the second end of each first motor is electrically connected to a first end of a second capacitor C2 through a second switch module K2.

[0131] Based on the above, in the active bleeding circuit including a plurality of excitation control circuits and a plurality of excitation windings, one excitation control circuit is correspondingly arranged with one excitation winding. The corresponding one excitation control circuit and excitation winding are referred to as one set of excitation components. In the case that the active bleeding circuit includes a plurality of sets of excitation components, the first end and the second end of the excitation control circuit of at least one set of excitation components are electrically connected to two ends of the bus capacitor (at least one of the first capacitor C1, the second capacitor C2 or the third bus capacitor C3). The bus capacitor is bled by the excitation components electrically connected to the two ends of the bus capacitor. The bleeding process is stable and reliable. On the one hand, no additional bleeding components such as bleeding resistors need to be arranged, saving the cost of the circuit. On the other hand, the motor will not produce abnormal sound and other problems during the bleeding process, improving the use experience.

[0132] The electrical connection mode of the excitation components and the bus capacitor (the first capacitor C1, the second capacitor C2 or the third bus capacitor C3) is shown in FIG. 13, and the electrical connection relationship of the excitation control circuit and the excitation winding is described above, which will not be described here.

[0133] Based on the above, the active bleeding circuit provided by some embodiments of the present disclosure can select the functional modules without faults and with temperatures within a safe range to actively bleed the bus capacitor when it is necessary to bleed the bus capacitor in the vehicle, thereby ensuring the safety of the vehicle.

[0134] For example, as shown in FIG. 13, in the case that at least one of the first capacitor C1, the second capacitor C2 and the third bus capacitor C3 needs to be bled, the first bleeding mode can be selected, that is, a corresponding set of first inverters and first winding coils electrically connected to the bus capacitor to be bled can be selected to bleed the bus capacitor. The bus capacitor (at least one of the first capacitor C1, the second capacitor C2 and the third bus capacitor C3), the first inverter and the first winding coil form a bleeding loop by controlling the on-off of the switching elements in the first inverter, and the bus capacitor is bled.

[0135] In the case of a fault or temperature overheat of the switching element in the first inverter, or temperature overheat of the first winding coil, a second discharge mode can be selected, which can be to select the excitation control circuit electrically connected across the bus capacitor, and the corresponding excitation winding to discharge the bus capacitor.

[0136] In the case of a fault or temperature overheat of the switching element in the first inverter, or temperature overheat of the first winding coil, a second discharge mode can be selected, which can be to select the excitation control circuit electrically connected across the bus capacitor, and the corresponding excitation winding to discharge the bus capacitor.

[0137] In the case of a fault or temperature overheat of the switching element in the first inverter, or temperature overheat of the first winding coil, a second discharge mode can be selected, which can be to select the excitation control circuit electrically connected across the bus capacitor, and the corresponding excitation winding to discharge the bus capacitor.

[0138] In the case of a fault or temperature overheat of the switching element in the first inverter, or temperature overheat of the first winding coil, a second discharge mode can be selected, which can be to select the excitation control circuit electrically connected across the bus capacitor, and the corresponding excitation winding to discharge the bus capacitor. The above merely provides specific embodiments of the present disclosure, but the protection scope of the present disclosure is not limited thereto, and any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present disclosure, which shall be covered within the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.

Claims

1. An active bleed circuit (110), comprising: at least one first capacitor (C1), a first end of the first capacitor (C1) configured to be electrically connected with a first pole of a battery, a second end of the first capacitor (C1) configured to be electrically connected with a second pole of the battery; a field control circuit, a first end and a second end of the field control circuit electrically connected with the first end and the second end of the first capacitor (C1) respectively; and a field winding, a first end and a second end of the field winding electrically connected with a third end and a fourth end of the field control circuit respectively; wherein the field control circuit is configured to form a bleed loop with the first capacitor (C1), the field control circuit and the field winding by controlling a conduction direction of the field control circuit.

2. The active bleeder circuit (110) of claim 1, wherein, The field control circuit is configured to form a first bleed loop by making the first end and the third end of the field control circuit conductive, and the second end and the fourth end of the field control circuit conductive, so that a current flows from the first end of the first capacitor (C1), through the first end to the third end of the field control circuit, the field winding, the fourth end to the second end of the field control circuit, and to the second end of the first capacitor (C1) in sequence.

3. The active bleeder circuit (110) of claim 2, wherein, The field control circuit is further configured to form a second bleed loop by making the first end and the third end of the field control circuit conductive, and the first end and the fourth end of the field control circuit conductive, so that a current flows from the second end of the field winding, through the fourth end to the first end of the field control circuit, the third end to the first end of the field control circuit in sequence.

4. The active bleeder circuit (110) of claim 2, wherein, The field control circuit is further configured to form a second bleed loop by making the second end and the third end of the field control circuit conductive, and the second end and the fourth end of the field control circuit conductive, so that a current flows from the second end of the field winding, through the fourth end of the field control circuit, the second end of the field control circuit, the third end of the field control circuit, to the first end of the field winding in sequence.

5. The active bleeding circuit (110) according to claim 3 or 4, wherein The active bleed circuit (110) is capable of switching between a first phase and a second phase during the bleeding of the first capacitor (C1); The field control circuit is configured to form part of the first bleed loop in the first phase, and to form part of the second bleed loop in the second phase.

6. The active bleed circuit (110) according to any one of claims 1-5, further comprising: at least one second capacitor (C2), a second end of the second capacitor (C2) electrically connected with the second end of the first capacitor (C1); in the case of charging the battery, or discharging the battery to the outside, a first end and a second end of the second capacitor (C2) electrically connected with a first pole and a second pole of a charge-discharge port respectively; at least one first inverter, a first pole and a second pole of the first inverter electrically connected with the first end and the second end of the first capacitor (C1) respectively; and at least one first motor, a first end of the first motor electrically connected with a third pole of the first inverter.

7. The active bleeder circuit (110) according to claim 6, wherein In a case where the voltage of the second capacitor (C2) is greater than zero and the absolute value of the voltage difference between the second capacitor (C2) and the first capacitor (C1) is less than a set threshold, a third discharge loop is formed by making the current pass from the first end of the second capacitor (C2), through the first end to the third end of the excitation control circuit, the excitation winding, the fourth end to the second end of the excitation control circuit, and the second end of the second capacitor (C2) in sequence.

8. The active bleeder circuit (110) of claim 6, wherein, In a case where the voltage of the second capacitor (C2) is greater than zero and less than the voltage of the first capacitor (C1), and the voltage difference between the first capacitor (C1) and the second capacitor (C2) is greater than or equal to a set threshold, a fourth discharge loop is formed by making the current pass from the first end of the second capacitor (C2), through the first motor, the first inverter, the first end to the third end of the excitation control circuit, the excitation winding, the fourth end to the second end of the excitation control circuit, and the second end of the second capacitor (C2) in sequence.

9. The active bleeding circuit (110) according to any one of claims 6-8, wherein, During the discharging of the second capacitor (C2), the active discharge circuit (110) can be switched between a first stage and a second stage; The excitation control circuit is configured to form part of the third discharge loop or part of the fourth discharge loop in the first stage, and form part of the second discharge loop in the second stage.

10. The active bleeding circuit (110) according to any one of claims 6-9, wherein, The active discharge circuit (110) further comprises: at least one first switch module (K1), the first end of the first capacitor (C1) being electrically connected to the first end of the second capacitor (C2) through the first switch module (K1); and at least one second switch module (K2), the second end of the first motor being electrically connected to the first end of the second capacitor (C2) through the second switch module (K2).

11. The active bleeder circuit (110) according to claim 10, wherein In a case where the voltage of the second capacitor (C2) is greater than zero and the absolute value of the voltage difference between the second capacitor (C2) and the first capacitor (C1) is less than a set threshold, the first switch module (K1) is closed, and the second switch module (K2) is opened.

12. The active bleeder circuit (110) of claim 10, wherein, In a case where the voltage of the second capacitor (C2) is greater than zero and less than the voltage of the first capacitor (C1), and the voltage difference between the first capacitor (C1) and the second capacitor (C2) is greater than or equal to a set threshold, the first switch module (K1) is opened, and the second switch module (K2) is closed.

13. The active bleeder circuit (110) according to claim 9 or 10, wherein The first inverter comprises: a multi-phase first bridge arm; the two ends of each phase first bridge arm in the multi-phase first bridge arm are electrically connected to the first pole and the second pole of the first inverter, respectively; Each phase first bridge arm comprises: a first switching element and a second switching element, the common connection end of the first switching element and the second switching element serving as a third pole of the first inverter; The first switch element includes a first transistor and a first diode, and the second switch element includes a second transistor and a second diode; the first transistor and the first diode are connected in parallel between a first pole of the first inverter and a third pole; the second transistor and the second diode are connected in parallel between a second pole of the first inverter and a third pole; The first motor includes: a plurality of groups of first winding coils; a first end of each group of the first winding coils is electrically connected to a third pole of the first inverter; in the case of charging the battery or discharging the battery, a second end of each group of the first winding coils is electrically connected to a first pole of the charging and discharging port.

14. The active bleeder circuit (110) of claim 13, wherein, In the case of forming the fourth discharge loop, the first transistor and the second transistor of at least one phase bridge arm in the multi-phase first bridge arm are turned off, the first diode is turned on, and the second diode is turned off.

15. The active bleeding circuit (110) according to any one of claims 10-14, wherein, The at least one first capacitor (C1) includes a plurality of first capacitors (C1), the at least one second capacitor includes a plurality of second capacitors (C2), the at least one first inverter includes a plurality of first inverters, the at least one first motor includes a plurality of first motors, the at least one first switch module (K1) includes a plurality of first switch modules (K1), and the at least one second switch module (K2) includes a plurality of second switch modules (K2); The first end and the second end of the excitation control circuit are respectively electrically connected to two ends of each first capacitor (C1) in the plurality of first capacitors (C1); A first end of each second capacitor (C2) in the plurality of second capacitors (C2) is electrically connected to a first end of a first capacitor (C1) through a corresponding first switch module (K1), and a second end of the each second capacitor (C2) is electrically connected to a second end of the first capacitor (C1); A first pole and a second pole of each first inverter in the plurality of first inverters are respectively electrically connected to two ends of a first capacitor (C1); A first end of each first motor in the plurality of first motors is electrically connected to a third pole of a first inverter, and a second end of the each first motor is electrically connected to a first end of a second capacitor (C2) through a second switch module (K2).

16. The active bleeding circuit (110) according to any one of claims 6-15, wherein, The battery includes: a first sub-battery (E1) and a second sub-battery (E2) connected in series; the first sub-battery (E1) and the second sub-battery (E2) connected in series are electrically connected between a first pole and a second pole of the battery; The active discharge circuit (110) further includes: A third bus capacitor, a first end and a second end of the third bus capacitor are respectively electrically connected to the first pole and the second pole of the battery, and the first end and the second end of the third bus capacitor are respectively electrically connected to the first end and the second end of the excitation control circuit; A second inverter, a first pole and a second pole of the second inverter are respectively electrically connected to two ends of the second capacitor (C2); and A third bus capacitor, a first end and a second end of the third bus capacitor are respectively electrically connected to the first pole and the second pole of the battery, and the first end and the second end of the third bus capacitor are respectively electrically connected to the first end and the second end of the excitation control circuit; A second inverter, a first pole and a second pole of the second inverter are respectively electrically connected to two ends of the second capacitor (C2); and A second motor, a first end of the second motor is electrically connected with the third pole of the second inverter, and a second end of the second motor is electrically connected to the common connection end of the first sub-battery (E1) and the second sub-battery (E2).

17. The active bleeder circuit (110) of claim 16, wherein, The excitation control circuit is configured to: by making the first end and the third end of the excitation control circuit conductive, and the second end and the fourth end of the excitation control circuit conductive, a fifth discharge loop is formed by the current from the first end of the third bus capacitor, through the first end of the excitation control circuit, the third end of the excitation control circuit, the excitation winding, the fourth end of the excitation control circuit, the second end of the excitation control circuit, to the second end of the third bus capacitor.

18. The active bleeding circuit (110) according to any one of claims 1-17, wherein, The excitation control circuit comprises: a third transistor (VT7), a fourth transistor (VT10), a third diode (VD7), a fourth diode (VD10), a fifth diode (VD8) and a sixth diode (VD9); The third transistor (VT7) and the third diode (VD7) are connected in parallel between the first end and the third end of the excitation control circuit; The fourth transistor (VT10) and the fourth diode (VD10) are connected in parallel between the second end and the fourth end of the excitation control circuit; The fifth diode (VD8) is electrically connected between the second end and the third end of the excitation control circuit; The sixth diode (VD9) is electrically connected between the first end and the fourth end of the excitation control circuit.

19. The active bleeder circuit (110) of claim 18, wherein, The first end and the third end of the excitation control circuit are conductive, and the second end and the fourth end of the excitation control circuit are conductive, including: the third transistor (VT7) and the fourth transistor (VT10) are conductive, and the third diode (VD7), the fourth diode (VD10), the fifth diode (VD8) and the sixth diode (VD9) are cut off.

20. The active bleeder circuit (110) of claim 18, wherein, The first end and the third end of the excitation control circuit are conductive, and the first end and the fourth end of the excitation control circuit are conductive, including: the third transistor (VT7) is conductive, the fourth transistor (VT10) is cut off, and the third diode (VD7), the fourth diode (VD10) and the fifth diode (VD8) are cut off, and the sixth diode (VD9) is conductive.

21. The active bleeder circuit (110) of claim 18, wherein, The second end and the third end of the excitation control circuit are conductive, and the second end and the fourth end of the excitation control circuit are conductive, including: the third transistor (VT7) is cut off, the fourth transistor (VT10) is conductive, and the third diode (VD7), the fourth diode (VD10) and the sixth diode (VD9) are cut off, and the fifth diode (VD8) is conductive.

22. A charging and discharging system (100), comprising: The active discharge circuit (110) according to any one of claims 1-21; A battery (120), the first capacitor (C1) of the active discharge circuit (110) is connected in parallel between the two ends of the battery (120); and The active discharge circuit (110) according to any one of claims 1-21; A controller (130) is electrically connected with the excitation control circuit of the active bleeding circuit (110); the controller (130) is configured to: control the excitation control circuit to make the active bleeding circuit (110) form a bleeding loop and bleed the electric energy stored by the first capacitor (C1).

23. A vehicle (1000) comprising the charging and discharging system (100) according to claim 22.

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