WO2022206192A1

WO2022206192A1 - Power supply circuit, power supply system and vehicle

Info

Publication number: WO2022206192A1
Application number: PCT/CN2022/076214
Authority: WO
Inventors: 张志国
Original assignee: 珠海冠宇动力电池有限公司
Priority date: 2021-03-30
Filing date: 2022-02-14
Publication date: 2022-10-06
Also published as: CN112928747A

Abstract

Provided in the embodiments of the present application are a power supply circuit, a power supply system and a vehicle. The power supply circuit comprises: a first battery pack, a second battery pack, a first switch circuit, a second switch circuit, an energy storage circuit and a control circuit, wherein the first battery pack and the second battery pack are connected in series; and the control circuit is used for controlling the first switch circuit and the second switch circuit when the difference between electric quantities of the first battery pack and the second battery pack is greater than a preset threshold value, so as to control power transfer between the first battery pack and the second battery pack. In this way, by means of connecting the first battery pack and the second battery pack in series, power is supplied to a load with relatively high power by means of both the first battery pack and the second battery pack, and the power transfer is controlled to be performed between the first battery pack and the second battery pack only when the difference between the electric quantities of the first battery pack and the second battery pack is relatively great, such that the number of power transfers can be effectively reduced, and the power loss caused by power transfer is decreased, thereby effectively improving the efficiency of power transfer.

Description

Power supply circuit, power supply system and vehicle

This application claims the priority of the Chinese patent application with the application number 202110342309.9 and the application name "Power Supply Circuit, Power Supply System and Vehicle" filed with the China Patent Office on March 30, 2021, the entire contents of which are incorporated into this application by reference .

technical field

The present application relates to various fields of new energy vehicle technology, and in particular, to a power supply circuit, a power supply system and a vehicle.

Background technique

Mild Hybrid Electric Vehicle (MHEV) needs to be equipped with a 12V starter battery for starting the internal combustion engine and a 48V start-stop battery for the hybrid system. Among them, the 48V battery is mainly used to power equipment with high power such as air conditioners and electric turbochargers. In order to keep both batteries able to continuously supply power to the equipment, so that the vehicle can work normally, power transfer between the two batteries may be required.

In the prior art, the 12V battery and the 48V battery in the light hybrid vehicle are connected in parallel, so that the batteries can be charged respectively. During the operation of the battery, in order to balance the electric energy in the two batteries, an independent DC is required. The /DC converter transfers power from a 12V battery to a 48V battery, or from a 48V battery to a 12V battery.

However, when the power transfer between the two batteries is carried out through an independent DC/DC converter, the power transfer can only be completed through components such as inductance and capacitor in the DC/DC converter. Therefore, part of the power may be lost. Thus, the efficiency of power conversion is reduced.

SUMMARY OF THE INVENTION

Embodiments of the present application provide a power supply circuit, a power supply system, and a vehicle. By connecting two battery packs in series, the power conversion efficiency between the two battery packs is improved.

In a first aspect, an embodiment of the present application provides a power supply circuit, the power supply circuit includes: a first battery pack, a second battery pack, a first switch circuit, a second switch circuit, an energy storage circuit, and a control circuit.

Wherein, the first battery pack and the second battery pack are connected in series, and the connection point is connected to the first end of the energy storage circuit; the second end of the energy storage circuit is respectively connected to the first end of the first switch circuit. The first end is connected to the first end of the second switch circuit; the second end of the first switch circuit is connected to the first battery pack; the second end of the second switch circuit is connected to the second The battery pack is connected; the first switch circuit and the second switch circuit are both connected to the control circuit.

The control circuit is configured to control the first switch circuit and the second switch circuit when the electric quantity difference between the first battery pack and the second battery pack is greater than a preset threshold, so as to switch the The electricity in the first battery pack is transferred to the second battery pack through the energy storage circuit; or, the electricity in the second battery pack is transferred to the first battery pack through the energy storage circuit middle.

In a possible implementation manner, the control circuit is configured to control the first switch circuit to be turned on and the second switch circuit to be turned off, so as to transfer the power in the first battery pack to the In the energy storage circuit; and then control the first switch circuit to be turned off and the second switch circuit to be turned on, so as to transfer the electricity in the energy storage circuit to the second battery pack.

Or, the control circuit is configured to control the first switch circuit to be turned off and the second switch circuit to be turned on, so as to transfer the power in the second battery pack to the energy storage circuit; and then control the The first switch circuit is turned on and the second switch circuit is turned off, so as to transfer the power in the energy storage circuit to the first battery pack.

In a possible implementation, the circuit further includes an inverting circuit.

Wherein, one of the first switch circuit and the second switch circuit is respectively connected to the first end of the control circuit and the enable end of the controller through the inverting circuit; the first The switch circuit and the other switch circuit in the second switch circuit are respectively connected to the first end of the control circuit and the enable end of the control circuit through a non-inverting circuit.

In a possible implementation manner, the first switch circuit includes a first driver and a first transistor, and the second switch circuit includes a second driver and a second transistor.

Wherein, the first end of the first driver is connected with the first end of the first transistor; the second end of the first transistor is connected with the energy storage circuit; the third end of the first transistor is connected with The first battery pack is connected.

The first end of the second driver is connected to the first end of the second transistor; the second end of the second transistor is connected to the energy storage circuit; the third end of the second transistor is connected to the The second battery pack is connected; one of the first driver and the second driver is connected to the first end of the control circuit through the inverter circuit; the other of the first driver and the second driver A driver is connected to the first end of the control circuit.

In a possible implementation manner, the first transistor includes a first MOS transistor and a first diode, and the second transistor includes a second MOS transistor and a second diode.

Wherein, the first end of the first MOS transistor is connected to the first end of the first driver; the second end of the first MOS transistor is respectively connected to the energy storage circuit and the first diode. The first end is connected; the third end of the first MOS transistor and the second end of the first diode are both connected to the first battery pack.

The first end of the second MOS transistor is connected to the first end of the second driver; the second end of the second MOS transistor is respectively connected to the first end of the energy storage circuit and the second diode The third end of the second MOS transistor and the second end of the second diode are both connected to the second battery pack.

In a possible implementation manner, the first battery pack and the second battery pack each include at least one battery cell, and the voltages of each battery cell are equal.

In a possible implementation, the tank circuit includes an inductor.

In a possible implementation manner, the inverting circuit includes an inverter; the non-inverting circuit includes an inverting device.

In a second aspect, an embodiment of the present application provides a power supply system method, where the power supply system includes the power supply circuit and the load described in any possible implementation manner of the foregoing first aspect.

In a third aspect, an embodiment of the present application provides a vehicle, where the vehicle includes the power supply circuit provided by any possible implementation manner of the above-mentioned first aspect.

It can be seen that the embodiments of the present application provide a power supply circuit, a power supply system, and a vehicle, and the power supply circuit includes a first battery pack, a second battery pack, a first switch circuit, a second switch circuit, an energy storage circuit, and a control circuit; The first battery pack and the second battery pack are connected in series, and the connection point is connected to the first end of the energy storage circuit; the second end of the energy storage circuit is respectively connected to the first end of the first switch circuit and the first end of the second switch circuit. one end is connected; the second end of the first switch circuit is connected to the first battery pack; the second end of the second switch circuit is connected to the second battery pack; the first switch circuit and the second switch circuit are both connected to the control circuit; a circuit for controlling the first switch circuit and the second switch circuit, so as to transfer the electricity in the first battery group to the second battery group through the energy storage circuit; or, to transfer the electricity in the second battery group through the energy storage circuit The circuit is transferred to the first battery pack. In this way, by connecting the first battery pack and the second battery pack in series, the first battery pack and the second battery pack can jointly supply power to the load with higher power, and only when the power difference between the first battery pack and the second battery pack is When the value is larger, the power transfer between the first battery pack and the second battery pack will be controlled, which can effectively reduce the number of power transfers, reduce the power loss caused by the power transfer, and effectively improve the power transfer efficiency. efficiency.

Description of drawings

1 is a schematic structural diagram of a power supply circuit provided by an embodiment of the present application;

FIG. 2 is a schematic structural diagram of another power supply circuit provided by an embodiment of the present application;

3 is a schematic structural diagram of a first switch circuit and a second switch circuit according to an embodiment of the present application;

4 is a schematic diagram of a circuit structure of a first transistor and a second transistor provided by an embodiment of the present application;

FIG. 5 is a schematic structural diagram of still another power supply circuit according to an embodiment of the present application.

The above-mentioned drawings have shown clear embodiments of the present disclosure, and will be described in more detail hereinafter. These drawings and written descriptions are not intended to limit the scope of the disclosed concepts in any way, but rather to illustrate the disclosed concepts to those skilled in the art by referring to specific embodiments.

Detailed ways

Exemplary embodiments will be described in detail herein, examples of which are illustrated in the accompanying drawings. Where the following description refers to the drawings, the same numerals in different drawings refer to the same or similar elements unless otherwise indicated. The implementations described in the illustrative examples below are not intended to represent all implementations consistent with this disclosure. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present disclosure as recited in the appended claims.

In the embodiments of the present application, "at least one" refers to one or more, and "a plurality" refers to two or more. "And/or", which describes the association relationship of the associated objects, means that there can be three kinds of relationships, for example, A and/or B, which can mean that A exists alone, A and B exist at the same time, and B exists alone, where A and B can be singular or plural. In the text description of this application, the character "/" generally indicates that the contextual object is an "or" relationship.

The technical solutions provided in the embodiments of the present application can be applied to the scenario of vehicle battery power conversion. Light hybrid vehicles use generators and batteries to drive with electric energy at the stage of idling or parking when the gasoline consumption is large, and switch to gasoline engine driving after reaching a certain speed, without plug-in charging, through the generator and kinetic energy The recycling unit charges the battery. Mild hybrid vehicles require a 12V starter battery for internal combustion engine starting and a 48V start-stop battery for hybrid systems. Among them, the 48V battery is mainly used to power equipment with high power such as air conditioners, electric turbochargers, steering systems, and engine cooling systems. In order to keep both batteries capable of continuously supplying power to the device, so that the vehicle can work normally, power transfer between the two batteries may be required.

However, when the power transfer between the two batteries is carried out through an independent DC/DC converter, the power transfer can only be completed through components such as the inductor and capacitor in the DC/DC converter, which may cause a part of the power loss, thereby reducing the power consumption. the power conversion efficiency.

In order to solve the problem of low conversion efficiency due to the loss of electric energy when the electric energy is transferred between the two batteries through an independent DC/DC converter. The first battery pack and the second battery pack can be connected in series, so that the first battery pack and the second battery pack can be charged at the same time through one interface, in addition, the two battery packs can simultaneously supply power to a higher power load, only in the first battery pack. The power transfer is performed only when the power difference between the first battery pack and the second battery pack is relatively large, which can reduce the power loss caused by the power transfer, thereby improving the efficiency of the power transfer.

Based on the above technical concept, an embodiment of the present application provides a power supply circuit, the power supply circuit includes a first battery pack, a second battery pack, a first switch circuit, a second switch circuit, an energy storage circuit, and a control circuit; A battery pack and a second battery pack are connected in series, and the connection point is connected to the first end of the energy storage circuit; the second end of the energy storage circuit is respectively connected to the first end of the first switch circuit and the first end of the second switch circuit The second end of the first switch circuit is connected to the first battery pack; the second end of the second switch circuit is connected to the second battery pack; the first switch circuit and the second switch circuit are both connected to the control circuit; the control circuit, using To control the first switch circuit and the second switch circuit to transfer the electricity in the first battery pack to the second battery pack through the energy storage circuit; or, to transfer the electricity in the second battery pack to the second battery pack through the energy storage circuit in the first battery pack.

It can be seen that, in the power supply circuit provided by the embodiment of the present application, by connecting the first battery pack and the second battery pack in series, the first battery pack and the second battery pack can be charged at the same time through one interface, and the first battery pack can be charged at the same time. During the use of the battery pack and the second battery pack, the first battery pack and the second battery pack can jointly supply power to the load with higher power. Only when the power difference between the first battery pack and the second battery pack is large, The power transfer is performed only before the power transfer, which can effectively reduce the number of power transfers, reduce the power consumption, and thus improve the efficiency of the power transfer.

Hereinafter, the power supply circuit provided by the embodiments of the present application will be described in detail through specific embodiments. It can be understood that the following specific embodiments may be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

FIG. 1 is a schematic structural diagram of a power supply circuit provided by a novel embodiment of the present application. As shown in FIG. 1 , the power supply circuit provided by the embodiment of the present application includes: a first battery pack 11 , a second battery pack 12 , a first switch circuit 13 , a second switch circuit 14 , an energy storage circuit 15 , and a control circuit 16 .

The first battery pack 11 and the second battery pack 12 are connected in series, and the connection point is connected to the first end of the energy storage circuit 15; the second end of the energy storage circuit 15 is respectively connected to the first end and the second end of the first switch circuit 13 The first ends of the two switch circuits 14 are connected; the second ends of the first switch circuits 13 are connected to the first battery pack 11 ; the second ends of the second switch circuits 11 are connected to the second battery pack 12 ; the first switch circuits 13 and The second switch circuits 14 are all connected to the control circuit;

The control circuit 16 is used to control the first switch circuit 13 and the second switch circuit 14 when the difference between the power of the first battery pack and the second battery pack is greater than a preset threshold, so as to pass the power in the first battery pack 11 through The energy storage circuit 15 is transferred to the second battery pack 12 ; or, the power in the second battery pack 12 is transferred to the first battery pack 11 through the energy storage circuit 15 . Wherein, the control circuit 16 may be a power supply controller, or may be other devices for controlling the first switch circuit 13 and the second switch circuit 14, which are not limited in this embodiment of the present application.

The tank circuit 15 includes an inductor.

In the embodiment of the present application, the energy storage circuit 15 includes an inductance. Since the first battery pack 11 and the second battery pack 12 are connected in series, the line length of the power supply circuit is shortened, and the use of an inductance for filtering is avoided, so that the first battery pack 11 can pass through the first battery pack. The group 11 and the second battery group 12 can realize the function of filtering the circuit and reduce the equipment cost of the power supply circuit.

Exemplarily, when the control circuit 16 controls the first battery pack 11 and the second battery pack 12 to perform power transfer, the control circuit 16 is used to control the first switch circuit 13 to be turned on and the second switch circuit 14 to be turned off, so that the The power in a battery pack 11 is transferred to the energy storage circuit 15 ; then the first switch circuit 13 is turned off and the second switch circuit 14 is turned on, so as to transfer the power in the storage circuit 15 to the second battery pack 12 ; Or; the control circuit 16 is used to control the first switch circuit 13 to be turned off and the second switch circuit 14 to be turned on, so as to transfer the power in the second battery pack 12 to the energy storage circuit 15; and then control the first switch circuit 13 is turned on, and the second switch circuit 14 is turned off, so as to transfer the power in the energy storage circuit 15 to the first battery pack 11 .

Before the control circuit 16 controls the first battery pack 11 and the second battery pack 12 to perform power transfer, the control circuit 16 can first detect the power of the first battery pack 11 and the second battery pack 12 and calculate the power of the first battery pack 11 If the difference from the power of the second battery pack 12 exceeds a preset threshold, the control circuit 16 controls the circuit to perform power transfer. Wherein, if the power of the first battery pack 11 is greater than the power of the second battery pack 12, the control will transfer the power in the first battery pack 11 to the second battery pack 12 through the energy storage circuit 15; if the second battery pack 12 The power of the battery pack 12 is greater than that of the first battery pack 11 , and the control transfers the power in the second battery pack 12 to the first battery pack 11 through the energy storage circuit 15 .

As an example, assuming that the power in the first battery pack 11 is controlled to be transferred to the second battery pack 12 through the energy storage circuit 15, the control circuit 16 controls the first switch circuit 13 to be turned on and the second switch circuit 14 to be turned off, that is, The first battery pack 11 , the first switch 13 and the energy storage circuit 15 form a loop, so that the current flows from the positive pole of the first battery pack 11 through the first switch circuit 13 and the energy storage circuit 15 , and returns to the negative pole of the first battery pack 11 , so that the power in the first battery pack 11 is transferred to the energy storage circuit 15 . Since the current in the circuit is gradually increased during this process, the control circuit 16 monitors the current in the circuit during this process, and when the current in the circuit reaches the current threshold, it means the amount of electricity stored in the energy storage circuit 15 to its maximum capacity. The current threshold is related to the capacity of the energy storage circuit in the circuit to store electricity, which is not limited in the embodiment of the present application.

It can be understood that, if the power in the second battery pack 12 is transferred to the first battery pack 11 , the process of the power transfer is similar to the above, which is not repeated in this embodiment of the present application.

Further, when the current in the circuit reaches the preset threshold, the control circuit 16 controls the first switch circuit 13 to be turned off and the second switch circuit 14 to be turned on, so that the polarity of the energy storage circuit is reversed, and the current direction remains unchanged. That is, the second battery pack 12 , the tank circuit 15 and the second switch circuit 14 form a loop, and the current flows from the positive pole of the second battery pack 12 through the tank circuit 15 and the second switch circuit 14 , and returns to the second battery pack 12 the negative pole of the battery, so as to transfer the power in the energy storage circuit 15 to the second battery pack 12 .

It can be understood that, when the power in the first battery pack 11 is transferred to the second battery pack 12 through the energy storage circuit 15, since the power stored in the energy storage circuit is limited, the power of the first battery pack 11 and The power of the second battery pack 12 is transferred multiple times, and the embodiment of the present application does not make any limitation on the number of times of power transfer.

In the embodiment of the present application, the first switch circuit 13 and the second switch circuit 14 are controlled to be turned on and off by the control circuit 16, so as to transfer the electricity in one of the battery packs to the energy storage circuit 15, and store the energy in the energy storage circuit 15. The power stored in the energy circuit 15 is transferred to another battery pack, so as to control the transfer of power between the two battery packs, so that the power in the first battery pack 11 and the second battery pack 12 is balanced, thereby ensuring that the battery packs are Both the 11 and the second battery pack 12 can supply power to the load to ensure the normal operation of the vehicle.

Further, the power supply circuit provided in this embodiment of the present application may further include an inverting circuit 17 and a non-inverting circuit 18 . One of the first switch circuit 13 and the second switch circuit 14 is connected to the first end of the control circuit 16 and the enable end of the controller 16 respectively through the inverting circuit 17; the first switch circuit 13 and the second switch circuit 14 The other switch circuit is connected to the first terminal of the control circuit 16 and the enabling terminal of the controller 16 respectively through the non-inverting circuit 18 . Wherein, the inverting circuit 17 includes an inverter, and the non-inverting circuit 18 includes an inverting device.

Wherein, one switch circuit of the first switch circuit 13 and the second switch circuit 14 is connected to the first end of the control circuit 16 through the inverter circuit 17; the other switch circuit of the first switch circuit 13 and the second switch circuit 14 is connected through The non-inverting circuit 18 is connected to the first end of the control circuit 16 . The inverter and the inverter can control the signals received by the first switch circuit 13 and the second switch circuit 14 to be opposite, that is, to control the first switch circuit 13 and the second switch circuit 14 to be on and off respectively. state.

It can be understood that by connecting one switch circuit of the first switch circuit 13 and the second switch circuit 14 to the enable terminal of the controller 16 through the inverter circuit 17; A switch circuit is connected to the enable terminal of the controller 16 through the non-inverting circuit 18 . When the first battery pack 11 and the second battery pack 12 do not need to perform power conversion, the enable terminal of the control circuit 16 can control the first switch circuit 13 and the second switch circuit 14 to be in an off state. Wherein, when the enable terminal of the control circuit 16 is valid, the first switch circuit 13 and the second switch circuit 14 are both turned off; when the enable terminal of the control circuit 16 is invalid, the first switch circuit 13 and the second switch Circuit 14 is in two opposite states.

In the embodiment of the present application, the first switch circuit 13 is respectively connected to the first terminal of the control circuit 16 and the enable terminal of the control circuit 17 through the inverting circuit 17 , and the second switch circuit 14 is respectively connected to the second terminal of the controller 16 through the non-inverting circuit 18 . The connection between one end and the enabling end of the control circuit 16 is taken as an example for description, but it does not mean that the embodiment of the present application is limited to this. Referring to FIG. 2 , FIG. 2 is a schematic structural diagram of another power supply circuit provided by an embodiment of the present application.

As shown in FIG. 2 , the control circuit 16 controls the conduction states of the first switch circuit 13 and the second switch circuit 14 to transfer the power in the first battery pack 11 to the second battery pack 12 , or transfer the second battery pack 12 . When the power in the battery pack 12 is transferred to the first battery pack 11, the control circuit 16 needs to be able to control the conduction state of the first switch circuit 13 and the second switch circuit 14 through the inverting circuit 17 and the non-inverting circuit 18, so that the first The conduction states of the switch circuit 13 and the second switch circuit 14 are opposite. For example, the second switch circuit 14 may be controlled to be turned off while the first switch circuit 13 is controlled to be turned on.

In the embodiment of the present application, the first switch circuit 13 and the second switch circuit 14 can be in different states through only one signal of the control circuit 16 through the inverting circuit 17 and the non-inverting circuit 18 . In addition, the first switch circuit 13 and the second switch circuit 14 are controlled by the enable terminal of the control circuit 16 to be in an off state, so that the first battery pack 11 and the second battery pack 12 cannot transfer power. It avoids the need to control the first switch circuit 13 and the second switch circuit 14 through different control circuits 17 respectively, and saves the use of equipment for controlling the circuit 17 .

FIG. 3 is a schematic structural diagram of a first switch circuit and a second switch circuit according to an embodiment of the present application.

As shown in FIG. 3 , the first switch circuit 13 includes a first transistor 131 and a first driver 132 , and the second switch circuit 14 includes a second transistor 141 and a second driver 142 ; wherein the first end of the first driver 132 is connected to the first end of the first driver 132 . The first end of the first transistor 131 is connected to the energy storage circuit; the third end of the first transistor 131 is connected to the first battery pack 11 . The first end of the second driver 142 is connected to the first end of the second transistor 141; the second end of the second transistor 141 is connected to the tank circuit; the third end of the second transistor 141 is connected to the second battery pack 12; One of the first driver 132 and the second driver 142 is connected to the first terminal of the control circuit 16 through the inverter circuit 17 ; the other driver of the first driver 132 and the second driver 142 is connected to the first terminal of the control circuit 16 . The embodiments of the present application are described by taking the first driver 132 being connected to the first end of the control circuit 17 through the inverter circuit 16, and the second driver 142 being connected to the first end of the control circuit 17 as an example, but it does not represent the present application. Embodiments are limited to this.

For example, when the control circuit 16 controls the conduction states of the first switch circuit 13 and the second switch circuit 14 , the voltage output by the control circuit 16 is adjusted by the first driver 132 and the second driver 142 . For example, the voltage output by the first driver 132 makes the first transistor 131 in an on state, while the voltage output by the second driver 142 makes the second transistor 141 in an off state. The first transistor 131 and the second transistor 141 may be body diodes, and the embodiments of the present application are only described as examples, but do not mean that the embodiments of the present application are limited thereto.

In the embodiment of the present application, the conduction states of the first transistor 131 and the second transistor 141 are controlled by the first driver 132 and the second driver 131 respectively, so that the conduction states of the first transistor 131 and the second transistor 141 are more accurate, Thus, the efficiency of power conversion between the first battery pack 11 and the second battery pack 12 is improved.

FIG. 4 is a schematic diagram of a circuit structure of a first transistor and a second transistor according to an embodiment of the present application.

As shown in FIG. 4 , the first transistor 131 includes a first diode D1 and a first MOS transistor M1, and the second transistor 141 includes a second diode D2 and a second MOS transistor M2. Wherein, the first end of the first MOS transistor M1 is connected to the first end of the first driver 132; the second end of the first MOS transistor M1 is respectively connected to the energy storage circuit 15 and the first end of the first diode D1; The third end of the first MOS transistor M1 and the second end of the first diode D1 are both connected to the first battery pack 11 . The first end of the second MOS transistor M2 is connected to the first end of the second driver 142; the second end of the second MOS transistor M2 is connected to the tank circuit 15 and the first end of the second diode D2 respectively; The third end of the MOS transistor M2 and the second end of the second diode D2 are both connected to the second battery pack 12 .

The first diode D1 and the second diode D2 are the same, and the first MOS transistor M1 and the second MOS transistor M2 are the same. And the first ends of the first MOS transistor M1 and the second MOS transistor M2 are both the G end, the second end is the S end, and the third end is the D end. When there is a pressure difference between the G end and the S end, the MOS transistor is in the conducting state.

In the embodiment of the present application, the first transistor 131 includes a first diode D1 and a first MOS transistor M1, and the second transistor 141 includes a second diode D2 and a second MOS transistor M2, so that the control circuit 16 can control the The conduction state of the first transistor 131 and the second transistor 141, so as to perform power transfer.

Exemplarily, both the first battery pack 11 and the second battery pack 12 include at least one battery cell, and the voltages of the respective battery cells are equal. Wherein, the electric capacity of the first battery pack 11 and the second battery pack 12 are equal. For example, if the vehicle needs a battery with a voltage of 12V and a power of 30AH, and a battery with a voltage of 48V and a power of 60AH, the first battery pack 11 can be three batteries with a voltage of 12V and a power of 10AH. The second battery pack 12 can be a storage battery with a voltage of 12V and a power of 10AH. By connecting two battery packs in series, a battery with a voltage of 12V and a power of 30AH, and a battery with a voltage of 48V and a power of 60AH can be obtained. Compared with the prior art by connecting a battery with a voltage of 12V and a power of 30AH and a battery with a voltage of 48V and a power of 60AH in parallel, a battery with a voltage of 12V and a power of 30AH can be saved.

In the embodiment of the present application, the first battery pack 11 and the second battery pack 12 each include at least one battery unit, which can charge the first battery pack 11 and the second battery pack 12, so that the first battery pack 11 and the second battery pack 12 can be charged. Group 12 is capable of continuously supplying power to the loads in the vehicle.

It can be seen from this that the power supply circuit provided by the embodiments of the present application includes a first battery pack, a second battery pack, a first switch circuit, a second switch circuit, an energy storage circuit, and a control circuit; wherein, the first battery pack and the second battery pack The battery packs are connected in series, and the connection point is connected to the first end of the energy storage circuit; the second end of the energy storage circuit is respectively connected to the first end of the first switch circuit and the first end of the second switch circuit; The second end is connected to the first battery pack; the second end of the second switch circuit is connected to the second battery pack; the first switch circuit and the second switch circuit are both connected to the control circuit; the control circuit is used to control the first switch circuit and a second switch circuit to transfer the power in the first battery group to the second battery group through the energy storage circuit; or, to transfer the power in the second battery group to the first battery group through the energy storage circuit. By connecting the first battery pack and the second battery pack in series, the first battery pack and the second battery pack can simultaneously supply power to a load with larger power, and only when the power difference between the first battery pack and the second battery pack is greater In the case of controlling the power transfer, the number of power transfers is reduced, the power loss caused by the power transfer is reduced, and the efficiency of the power transfer is improved.

As shown in Figure 5, the first battery pack of the power supply circuit is composed of three 12V/10AH batteries, namely B1, B2, and B3, and the second battery pack is one 12V/30AH battery, namely B1. The first driver is respectively connected to the first terminal of the power supply controller and the enable terminal EN of the power supply controller through the inverter A1, and the second driver is respectively connected to the first terminal of the power supply controller and the power supply controller through the inverter A2. The enable terminal EN is connected. Of course, the first driver can also be connected to the first terminal of the power supply controller and the enabling terminal EN of the power supply controller respectively through the inverter A2, and the second driver can also be respectively connected to the first terminal of the power supply controller through the inverter A1. It is connected to the enable terminal EN of the power supply controller. The embodiment of the present application only takes the connection manner shown in FIG. 5 as an example for description, but it does not mean that the embodiment of the present application is limited to this.

When using the battery to supply power to the load, it is assumed that the power in each battery is the maximum value of its capacity. Since the first battery pack B2, B3, B4, and the second battery pack B1 can jointly supply power for loads with higher power, such as air conditioners, electric turbochargers, etc., and the second battery pack B1 also needs to be used for other loads separately Power supply, for example, to the system for starting the internal combustion engine. Therefore, in the process of using the first battery pack and the second battery pack, there may be a large difference in the power of the two battery packs, so that the load cannot be powered normally, and power transfer needs to be performed. That is, during the use of the first battery packs B2, B3, B4 and the second battery pack B1, the power supply controller is required to monitor them in real time, and calculate the power of the first battery packs B2, B3, B4 and the second battery pack. If the difference of the power of B1 is greater than the preset threshold, it is necessary to control the transfer of the power of the battery pack with the larger power to the battery pack with the smaller power, so that the power of the two battery packs is balanced. Among them, when the power of the first battery pack B2, B3, B4 and the power of the second battery pack B1 are transferred, it is necessary to control the enable terminal EN of the power supply controller to be valid, so that the signal sent by the power supply controller can control the battery pack. power transfer between.

When transferring the power of the first battery group B2, B3, B4 to the second battery group B1, the power supply controller outputs a control signal, which passes through the inverter A1 and the inverter A2, so that the first driver and the second driver respectively receive To the opposite control signal, through the first driver, the MOS tube M1 is controlled to be turned on, the MOS tube M2 is turned off, and the power of the first battery pack B2, B3, B4 is discharged to the inductor L through the MOS tube M1, and the power is stored in the inductor. L in. The power supply controller monitors the current in the circuit in real time. When the current in the circuit reaches the current threshold, the power supply controller outputs a control signal to control the MOS transistor M1 to be turned off and the MOS transistor M2 to be turned on. The polarity of the inductor L is reversed, the current direction remains unchanged, and the electricity stored in the inductor is transferred to the second battery pack B1 through the MOS transistor M2. At this time, the power supply controller continues to monitor the power in the first battery pack B2, B3, B4 and the second battery pack B1, and if the difference is still greater than the preset threshold, it continues to control the power in the first battery pack B2, B3, B4 The power is transferred into the second battery pack B1 until the power levels in the first battery packs B2, B3, B4 and the second battery pack B1 are balanced.

Exemplarily, when transferring the power of the second battery group B1 to the first battery groups B2, B3, and B4, the power supply controller outputs a control signal through the inverter A1 and the inverter A2, so that the first driver and the second The drivers respectively receive opposite control signals, and through the first driver, the MOS transistor M1 is controlled to be turned off and the MOS transistor M2 is turned on. middle. The power supply controller monitors the current in the circuit in real time. When the current in the circuit reaches the current threshold, the power supply controller outputs a control signal to control the MOS transistor M1 to be turned on and the MOS transistor M2 to be turned off. The polarity of the inductor L is reversed, the current direction remains unchanged, and the electricity stored in the inductor is transferred to the first battery packs B2, B3, and B4 through the MOS transistor M1. At this time, the power controller continues to monitor the power in the first battery pack B2, B3, B4 and the second battery pack B1, and if the difference is still greater than the preset threshold, it continues to control the transfer of the power in the first battery pack B1 to the second battery pack B1. In the two battery groups B2, B3, B4, until the first battery group B2, B3, B4 and the second battery group B1 are balanced.

It can be understood that when charging the first battery pack B2, B3, B4 and the second battery pack B1, you can directly charge 4 batteries by connecting the 48V pole, or you can connect the 48V pole and the 12V pole at the same time. Charge 4 batteries. Among them, when the 48V pole and the 12V pole are connected at the same time to charge the first battery pack B2, B3, B4 and the second battery pack B1, since the second battery pack B1 is connected with two poles at the same time for charging, it is possible It may happen that one of the first battery packs B2, B3, B4 and the second battery pack B1 is quickly fully charged, but the other battery pack cannot be charged, and power transfer is required. The process of the first battery pack B2, B3, B4 and the second battery pack B1 performing power transfer during the charging process and the above-mentioned method for performing power transfer during the use of the first battery pack B2, B3, B4 and the second battery pack B1 The same is not repeated in this embodiment of the present application.

For example, when power transfer is not required between the first battery pack B2, B3, B4 and the second battery pack B1, the enable terminal EN of the power supply controller can be controlled to be invalid, so that the control MOS transistor M1 and the MOS transistor M2 are both off state.

To sum up, in the power supply circuit provided by the embodiment of the present application, by connecting the first battery pack B2, B3, B4 and the second battery pack B1 in series, the two batteries can simultaneously supply power to a load with a relatively large power, which is different from the prior art. Compared with the method of connecting two batteries in parallel, the number of batteries can be saved. In addition, the power supply circuit connects the first battery pack and the second battery pack in series, which shortens the circuit line, so that noise and the like can be filtered through the filtering effect of the battery, avoiding the use of capacitors for filtering, and saving costs. During the power conversion process, the power transfer is performed only when the power difference between the first battery pack and the second battery pack is large, and a part of the power from the first battery pack can be directly transferred to the second battery pack, thereby improving the Efficiency of power transfer.

An embodiment of the present application further provides a power supply system, which includes the power supply circuit and the load in any of the above embodiments, and its implementation principle and beneficial effects are similar to those of the power supply circuit, and reference may be made to the realization of the power supply circuit The principle and beneficial effects will not be repeated here.

Embodiments of the present application also provide a vehicle, which includes the power supply circuit in any of the foregoing embodiments.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present application. scope.

Claims

A power supply circuit, comprising: a first battery pack, a second battery pack, a first switch circuit, a second switch circuit, an energy storage circuit and a control circuit;

Wherein, the first battery pack and the second battery pack are connected in series, and the connection point is connected to the first end of the energy storage circuit; the second end of the energy storage circuit is respectively connected to the first end of the first switch circuit. The first end is connected to the first end of the second switch circuit; the second end of the first switch circuit is connected to the first battery pack; the second end of the second switch circuit is connected to the second the battery pack is connected; the first switch circuit and the second switch circuit are both connected to the control circuit;

The control circuit is configured to control the first switch circuit and the second switch circuit when the electric quantity difference between the first battery pack and the second battery pack is greater than a preset threshold, so as to switch the The electricity in the first battery pack is transferred to the second battery pack through the energy storage circuit; or, the electricity in the second battery pack is transferred to the first battery pack through the energy storage circuit middle.
The circuit of claim 1, wherein:

The control circuit is used to control the first switch circuit to be turned on and the second switch circuit to be turned off, so as to transfer the power in the first battery pack to the energy storage circuit; and then control the The first switch circuit is turned off and the second switch circuit is turned on, so as to transfer the power in the energy storage circuit to the second battery pack;

or;

The control circuit is used to control the first switch circuit to be turned off and the second switch circuit to be turned on, so as to transfer the power in the second battery pack to the energy storage circuit; and then control the The first switch circuit is turned on and the second switch circuit is turned off, so as to transfer the power in the energy storage circuit to the first battery pack.
The circuit of claim 1, wherein the circuit further comprises an inverting circuit and a non-inverting circuit;

Wherein, one of the first switch circuit and the second switch circuit is respectively connected to the first end of the control circuit and the enable end of the controller through the inverting circuit; the first The switch circuit and the other switch circuit in the second switch circuit are respectively connected to the first end of the control circuit and the enable end of the control circuit through a non-inverting circuit.
The circuit of claim 3, wherein the first switch circuit includes a first driver and a first transistor, and the second switch circuit includes a second driver and a second transistor;

Wherein, the first end of the first driver is connected with the first end of the first transistor; the second end of the first transistor is connected with the energy storage circuit; the third end of the first transistor is connected with the first battery pack is connected;

The first end of the second driver is connected to the first end of the second transistor; the second end of the second transistor is connected to the energy storage circuit; the third end of the second transistor is connected to the The second battery pack is connected; one of the first driver and the second driver is connected to the first end of the control circuit through the inverter circuit; the other of the first driver and the second driver A driver is connected to the first end of the control circuit.
The circuit according to claim 4, wherein the first transistor comprises a first MOS transistor and a first diode, and the second transistor comprises a second MOS transistor and a second diode;

Wherein, the first end of the first MOS transistor is connected to the first end of the first driver; the second end of the first MOS transistor is respectively connected to the energy storage circuit and the first diode. the first end is connected; the third end of the first MOS transistor and the second end of the first diode are both connected to the first battery pack;

The first end of the second MOS transistor is connected to the first end of the second driver; the second end of the second MOS transistor is respectively connected to the first end of the energy storage circuit and the second diode The third end of the second MOS transistor and the second end of the second diode are both connected to the second battery pack.
The circuit according to any one of claims 1-5, characterized in that,

Both the first battery pack and the second battery pack include at least one battery cell, and the voltages of the respective battery cells are equal.
The circuit according to any one of claims 1-5, characterized in that,

The tank circuit includes an inductor.
The circuit of claim 3, wherein:

The inverting circuit includes an inverter; the non-inverting circuit includes an inverting device.
A power supply system, characterized in that it comprises the power supply circuit and the load according to any one of claims 1-8;

Wherein, the power supply circuit is used for supplying power to the load.
A vehicle, characterized by comprising the power supply circuit according to any one of the above claims 1-8.