CN220594838U

CN220594838U - Double-low-voltage power supply system for vehicle and vehicle

Info

Publication number: CN220594838U
Application number: CN202322341702.3U
Authority: CN
Inventors: 吕智勇
Original assignee: Shanghai Liqun Technology Co ltd
Current assignee: Shanghai Liqun Technology Co ltd
Priority date: 2023-08-30
Filing date: 2023-08-30
Publication date: 2024-03-15
Anticipated expiration: 2033-08-30

Abstract

The utility model discloses a double low-voltage power supply system for a vehicle and a vehicle, which comprise a first storage battery and a second storage battery, wherein the negative electrode of the first storage battery is grounded, the positive electrode of the first storage battery is connected with the negative electrode of the second storage battery to form a series battery pack, the positive electrode of the second storage battery leads out a second power supply positive electrode through a bidirectional conduction change-over switch S1, and the positive electrode of the first storage battery leads out a first power supply positive electrode; a common negative electrode is drawn at the negative electrode of the first battery. The utility model has the advantages that: the dual-low-voltage power supply system can provide dual-low-voltage power supply output, and can charge only one way of DCDC module, so that the cost of one DCDC module is saved compared with the prior art, only one high-voltage to low-voltage DCDC is needed, and the consistency of an automobile power supply framework and a traditional 12V framework is maintained; the circuit has simple and reliable structure, low cost and convenient popularization and implementation.

Description

Double-low-voltage power supply system for vehicle and vehicle

Technical Field

The utility model relates to the field of vehicle low-voltage power supply, in particular to a vehicle double-low-voltage power supply system and a vehicle.

Background

The traditional automobile only adopts a 12V storage battery to supply power for a low-voltage power supply, ignition and the like of the automobile, but with the development of the automobile, commercial automobiles and future high-power electric equipment are popular (such as electric power steering and electromechanical braking), and the automobile is powered by adopting two sets of voltages of 48V (24V) and 12V. An engine start control method for a 48V micro-hybrid system as claimed in patent application No. 201711347154.8 discloses an engine start method for a 48V micro-hybrid system, which introduces the functions of the 48, 12V micro-hybrid system in the background art: by adding 48V motor, battery and other parts on the original 12V automobile electrical system of the automobile, the functions of high-grade idle start-stop, engine working condition optimization, acceleration assistance, braking energy recovery and the like can be realized, the oil consumption of the whole automobile is reduced by 10-15%, and the drivability and NVH (noise and harshness) of the automobile are optimized.

Two sets of 48V and 12V power supply systems are adopted, generally, two batteries of 48V and 12V are adopted, and two DCDC modules are correspondingly adopted to convert electric energy generated by a power battery or a generator into electric energy of 48V and 12V for charging respectively. For the 48V and 12V double low-voltage storage battery system, two DCDC modules are needed to charge a 48V battery and a 12V battery respectively, so that the hardware cost caused by double DCDC is increased, and two DCDC modules are needed.

Disclosure of Invention

The utility model aims to overcome the defects of the prior art and provides a double low-voltage power supply system for a vehicle and the vehicle, wherein the double low-voltage power supply system can meet the requirement of 48V and 12V double low-voltage power supply and can charge the double low-voltage system by adopting one DCDC.

In order to achieve the above purpose, the technical scheme adopted by the utility model is as follows: the double low-voltage power supply system for the vehicle comprises a first storage battery and a second storage battery, wherein the negative electrode of the first storage battery is grounded, the positive electrode of the first storage battery is connected to the negative electrode of the second storage battery to form a series battery pack, the positive electrode of the second storage battery leads out a second power supply positive electrode through a bidirectional conduction change-over switch S1, and the positive electrode of the first storage battery leads out a first power supply positive electrode; a common negative electrode is drawn at the negative electrode of the first battery.

The first storage battery is a 12V storage battery.

The second storage battery is a 36V storage battery or a 12V storage battery.

And an outgoing terminal between the positive electrode of the first storage battery and the negative electrode of the second storage battery is connected to the second power supply positive electrode through a capacitor C1 and a bidirectional conduction change-over switch S2 which are connected in series in sequence.

And a resistor R1 is arranged in series between the positive electrode of the first storage battery and the negative electrode of the second storage battery.

And a lead-out terminal between the capacitor and the positive electrode of the first storage battery is grounded through an electronic switch S3 and a resistor R2.

The power supply system further comprises a control unit MCU, wherein the output end of the control unit MCU is connected to the bidirectional conduction change-over switch S1 and used for controlling the conduction direction of the bidirectional conduction change-over switch S1; the output end of the control unit MCU is connected to the bidirectional conduction change-over switch S2 and used for controlling the conduction direction of the bidirectional conduction change-over switch S2; the output end of the control unit MCU is connected to the control end of the electronic switch S3.

The control unit MCU leads out a CAN communication terminal through the CAN communication module, and the CAN communication terminal is used for being connected to a CAN network of the vehicle.

The first power supply positive electrode and the second power supply positive electrode are used for outputting corresponding low-voltage power supply and are used for being respectively connected with electric appliances with corresponding voltages; and during charging, the second power supply positive electrode and the negative electrode of the first storage battery are respectively connected to the positive electrode and the negative electrode of the output end of the vehicle-mounted charging DCDC module.

A vehicle adopts the double low-voltage power supply system for the vehicle to provide low-voltage power supply for the vehicle.

The utility model has the advantages that: the dual-low-voltage power supply system can provide dual-low-voltage power supply output, and can charge only one way of DCDC module, so that the cost of one DCDC module is saved compared with the prior art, only one high-voltage to low-voltage DCDC is needed, and the consistency of an automobile power supply framework and a traditional 12V framework is maintained; the circuit has simple and reliable structure, low cost and convenient popularization and implementation.

Drawings

The contents of the drawings and the marks in the drawings of the present specification are briefly described as follows:

FIG. 1 is a schematic diagram of a dual voltage power supply system of the present utility model;

fig. 2 is a schematic diagram of an embodiment of a bidirectional conduction switch according to the present utility model.

Detailed Description

The following detailed description of the utility model refers to the accompanying drawings, which illustrate preferred embodiments of the utility model in further detail.

The main purpose of the utility model is to improve the double low voltage system in the prior art to realize a new double low voltage system which can still meet the requirement of outputting double low voltage and does not need two DCDC to supply power. Conventional dual low voltage systems of 12V and 48V require a 12VDCDC and a 48VDCDC to charge the 12V battery and 48V battery, respectively. The present application is therefore directed to improvements in such dual low pressure systems, as follows:

the double low-voltage power supply system for the vehicle comprises a first storage battery and a second storage battery, wherein the negative electrode of the first storage battery is grounded, the positive electrode of the first storage battery is connected to the negative electrode of the second storage battery to form a series battery pack, the positive electrode of the second storage battery leads out a second power supply positive electrode through a bidirectional conduction change-over switch S1, and the positive electrode of the first storage battery leads out a first power supply positive electrode; a common negative electrode is drawn at the negative electrode of the first battery. Wherein the first storage battery is an aV storage battery, and the second storage battery is a bV storage battery; the first power supply positive electrode and the public negative electrode are used as a pair of power supplies for outputting power supply voltage a V outside the positive electrode and the negative electrode, and the first power supply positive electrode and the public negative electrode are connected to a vehicle-mounted low-voltage electric appliance requiring aV voltage; the second power supply positive electrode and the public negative electrode are used for being connected with the vehicle-mounted low-voltage electric appliance, the second power supply positive electrode and the public negative electrode of a power supply for providing (a+b) V voltage for the vehicle-mounted low-voltage electric appliance are connected to the vehicle-mounted low-voltage electric appliance needing (a+b) V voltage.

Because the double low-voltage system of this application is applied to the vehicle, consequently the vehicle can be provided with DCDC and charge for it, and when charging, the double low-voltage power supply system of this application, second power supply anodal, public negative pole are connected to the positive negative pole of on-vehicle DCDC module output that charges respectively, and this DCDC module is (a+b) V DCDC module for charge to whole double low-voltage power supply system. Because the circuit conduction directions of charging and discharging are different, the bidirectional conduction change-over switch is used in the application, when the DCDC module supplies power for the double-low-voltage power supply system, the conduction direction is controlled to be the direction from the second power supply positive electrode to the second storage battery through the S1 by the bidirectional conduction switch S1, namely, the current direction for controlling conduction is the direction from the DCDC module flowing out through the S1 and then flowing into the second storage battery positive electrode. Similarly, when the double low voltage system is discharged and a+bv voltage is required, the current direction is controlled to be the direction from the positive electrode of the second storage battery to the second power supply positive electrode through the S1 by controlling the S1, so that the a+bv voltage is provided for the vehicle. The output aV voltage is directly led out from the first power supply terminal and the common negative electrode without the control of S1, and of course, a switch may be provided, and the output of the first storage battery may be controlled by the switch.

In a preferred embodiment of the present application, the outgoing terminal between the first battery positive electrode and the second battery negative electrode is connected to the second power supply positive electrode sequentially via the capacitor C1 and the bidirectional conduction switch S2 connected in series. The capacitor C1 can be charged by controlling the conduction direction of the switch S2, and the capacitor C1 is discharged outwards to increase the instant discharging current of the double low-voltage system, so that the working conditions of some large current demands are met; if the 48V electrical appliance needs the instant heavy current, the turning-on directions of the S1 and the S2 are respectively controlled to be the direction from the positive electrode of the second storage battery to the second power supply positive electrode and the direction from the capacitor C1 to the second power supply positive electrode, so that the purpose of providing the instant heavy current for the electrical appliance can be realized; conversely, if the capacitor C1 is charged, the conduction of the switch S2 needs to be controlled with confidence to the flow direction from the second supply positive electrode to the capacitor C1. Of course, because the energy stored by the capacitor C1 is limited, in some cases, discharging is needed, for example, when the whole vehicle is powered down, so that the discharging of the capacitor C1 is needed at the moment, and therefore, the lead-out terminal is grounded between the capacitor and the positive electrode of the first storage battery through the electronic switch S3 and the resistor R2. Thus, the discharging of the capacitor C1 can be realized, and the discharging can be realized only by controlling the S3.

In a preferred embodiment, a protection resistor R1 is arranged in series between the positive electrode of the first battery and the negative electrode of the second battery for current limiting protection.

The on-off and the on-direction of the switches S1 and S2 are controlled by the control unit MCU, and the on-off of the switch S3 is controlled by the control unit MCU. The control unit MCU is a main control chip of a double-low-voltage control system, and is generally realized by adopting a battery management unit chip, and can also realize a control function by adopting a microcontroller such as a singlechip or the like, or can be realized by integrating the control unit MCU in a vehicle-mounted controller, and the MCU is worth noting that the MCU mainly realizes the control functions of the switches S1, S2 and S3. The connection relation is as follows: the output end of the control unit MCU is connected to the bidirectional conduction change-over switch S1 and used for controlling the conduction direction and disconnection of the bidirectional conduction change-over switch S1; the output end of the control unit MCU is connected to the bidirectional conduction change-over switch S2 and is used for controlling the conduction direction and the disconnection control of the bidirectional conduction change-over switch S2; the output end of the control unit MCU is connected to the control end of the electronic switch S3 and used for controlling whether the S3 is disconnected or not.

The MCU is used as a main control chip of the double-low-voltage control system, and CAN be controlled by the upper computer, and the upper computer is a vehicle-mounted controller on a vehicle because the MCU is applied to the vehicle, so that the MCU is added with a CAN communication function, and communication with the vehicle-mounted controller of the upper computer is realized. The control unit MCU leads out a CAN communication terminal through the CAN communication module, the CAN communication terminal is used for being connected to a CAN network of the vehicle, and communication with the vehicle-mounted controller CAN be realized through the CAN network, so that monitoring and control of the double-low-voltage power supply system are realized.

In a preferred embodiment the present application also provides a vehicle employing a dual low voltage power supply system for a vehicle of the present application to provide low voltage power to the vehicle.

The two storage batteries of the whole vehicle are 12V and 48V or 24V; the first storage battery is a 12V storage battery, and the second storage battery is a 36V storage battery or a 12V storage battery, so that a 12V and 48V dual low-voltage power supply system or a 12V and 24V dual low-voltage power supply system can be realized. Taking a 12V and 48V dual low voltage power supply system as an example, as shown in fig. 1, the positive electrode of the 12V storage battery is connected to the negative electrode of the 36V storage battery through a resistor R1, the positive electrode of the 36V storage battery is connected to a +48V power supply output terminal through a bidirectional conduction change-over switch S1, the terminal is used for outputting the positive electrode of the 48V power supply, meanwhile, the negative electrode of the 12V storage battery is grounded, and the negative electrode is also a public negative electrode and is used for being connected to the negative electrode of an electric appliance or the negative electrode of a charging DCDC. The +12v terminal is led out from the positive electrode of the 12V battery for connection to the positive electrode of a 12V electrical appliance, the negative electrode of which is grounded or connected to the negative electrode of the 12V battery. Thus, the +48 positive electrode and the common negative electrode realize the external output of a 48V power supply, and the +12V terminal and the common negative electrode form the external output of a 12V power supply. According to the method, only one 48VDCDC module is needed to charge, namely, a 48V DCDC module is integrated on a vehicle and connected to a +48V terminal and the negative electrode of a 12V storage battery, when the vehicle is charged, the conduction of the S1 is controlled, the charging of the 36V storage battery and the 12V storage battery is realized according to the conduction direction of current charging, and when the vehicle is discharged, the S1 is controlled to output 48V voltage. Because in some electrical apparatus instant heavy current service conditions, therefore this application power supply system still is provided with S2 and C1, and S2 is two-way switch-on, draws the terminal to be connected to +48V terminal after electric capacity C1, the S2 of establishing ties between resistance R1 and 36V battery negative pole, like this when charging C1 and the direction of switching on of control S2 when discharging. Further, under the premise of ensuring safety and the like, after electricity is supplied, the capacitor C1 needs to be discharged, so that a lead-out terminal between the negative electrode of the capacitor C1, namely the capacitors C1 and R1, is grounded through a switch S3 and a resistor R2 which are connected in series. The control unit MCU controls the on-off of the switch S3 to realize the release control.

In the application, the switch S3 adopts an electronic switch, and the MCU is used for controlling the switch to be turned on and off.

The bidirectional conduction switches S1 and S2 realize external discharging of the storage battery 36V or charging direction of the external DCDC to the storage battery 36V, and mainly control the conduction direction, namely the current direction, so that the purposes of charging and discharging are realized. The switches S1 and S2 are turned on in a bidirectional manner by adopting two MOS transistors connected in series, as shown in fig. 2, and the two MOS transistors MOS1 and MOS2 each have a parasitic diode. The grid electrodes of the MOS1 and the MOS2 are connected to the output end of the MCU, namely two output ends GPIO1 and FP IO2 of the MCO are adopted to respectively control the conduction of the two MOS tubes; the MOS1 and the MOS2 can adopt NMOS or PMOS, in fig. 2, the S electrode of the MOS1 and the S electrode of the MOS2 are connected together, the D electrode of the MOS1 and the D electrode of the MOS2 respectively lead out terminals to serve as two terminals of a bidirectional conduction change-over switch, the D electrode of the MOS1 serving as the S1 is connected to the D electrode of the +48V, MOS2 and is connected to the positive electrode of the 36V storage battery; the switch S2 connection is similar. Because the two MOS tubes are provided with the integrated diode, the purpose of bidirectional conduction switching control can be realized by controlling the conduction of the MOS1 and the MOS2 and combining the conduction effect of the parasitic diode.

In the scheme of the embodiment, the electric vehicle dual-voltage system only needs to be provided with one high-voltage 48VDCDC, and a 36V storage battery is additionally arranged, so that the consistency of an automobile power supply framework and a traditional 12V framework is maintained. The 36V module comprises a 36V5AH lithium battery, the capacitor C1 is a medium-sized capacitor, the controller switches S1 and S2 are serially connected MOS tubes, and the S3 is realized by adopting a single MOS tube, so that the realization is simple, convenient, low in cost, safe and reliable.

The utility model provides a can satisfy various power consumption demands on the vehicle is applied to two low voltage power supply system, consequently prestore the electric quantity in the C1, consequently can realize effects such as steady voltage or step down through control S1, S2 direction of switch on and time, and this application introduces as follows to the scene of its application: when the electric vehicle is powered outwards, charging or external power supply can be realized only by correspondingly connecting a corresponding 12V positive electrode or 48V positive electrode and a public negative electrode to a DCDC positive electrode or a DCDC positive electrode and a DCDC negative electrode, and meanwhile, when the electric vehicle is controlled, for example, when the 48V electric appliance is powered on after the vehicle is started, a large current is required instantaneously, a 36V module internal battery and an internal capacitor C1 and a 12V storage battery are provided together; when the 12V electric appliance requires instantaneous large current, the 12V storage battery supplies the current; the inside of the 36V module comprises an anti-reverse switch 1 and an anti-reverse switch 2, so that the reverse electromotive force is ensured not to influence the power supply, and the control of the conduction direction of the switches S1 and S2 is only needed; meanwhile, in the double low-voltage system, the closing of the switch S1 and the closing of the switch S2 are controlled, so that the voltage reduction function of 48V to 12V can be realized, and the closing time of the switch S2 is controlled as required by the closing of the switch S1, so that the voltage stabilization function of 48V to 12V can be realized; when the 36V battery power is high, the anti-reverse switch 1 is opened, and the anti-reverse switch 2 is closed; when the capacitance energy is high, the switch 3 is closed, and the capacitor is released through the shunt resistor; the anti-reverse switch 1, the anti-reverse switch 2 and the switch 3 are closed and opened by PWM control to realize opening and conducting control.

It is obvious that the specific implementation of the present utility model is not limited by the above-mentioned modes, and that it is within the scope of protection of the present utility model only to adopt various insubstantial modifications made by the method conception and technical scheme of the present utility model.

Claims

1. The utility model provides a two low voltage power supply system for automobile-used which characterized in that: the power supply device comprises a first storage battery and a second storage battery, wherein the negative electrode of the first storage battery is grounded, the positive electrode of the first storage battery is connected to the negative electrode of the second storage battery to form a series battery pack, the positive electrode of the second storage battery leads out a second power supply positive electrode through a bidirectional conduction change-over switch S1, and the positive electrode of the first storage battery leads out a first power supply positive electrode; a common negative electrode is drawn at the negative electrode of the first battery.

2. A dual low voltage power supply system for vehicles as claimed in claim 1, wherein: the first storage battery is a 12V storage battery.

3. A dual low voltage power supply system for vehicles as claimed in claim 1, wherein: the second storage battery is a 36V storage battery or a 12V storage battery.

4. A dual low voltage power supply system for vehicles as claimed in claim 1, wherein: and an outgoing terminal between the positive electrode of the first storage battery and the negative electrode of the second storage battery is connected to the second power supply positive electrode through a capacitor C1 and a bidirectional conduction change-over switch S2 which are connected in series in sequence.

5. A dual low voltage power supply system for vehicles as claimed in claim 1, wherein: and a resistor R1 is arranged in series between the positive electrode of the first storage battery and the negative electrode of the second storage battery.

6. A dual low voltage power supply system for vehicles as claimed in claim 4, wherein: and a lead-out terminal between the capacitor and the positive electrode of the first storage battery is grounded through an electronic switch S3 and a resistor R2.

7. A dual low voltage power supply system for vehicles according to any of claims 1-6, characterized in that: the power supply system further comprises a control unit MCU, wherein the output end of the control unit MCU is connected to the bidirectional conduction change-over switch S1 and used for controlling the conduction direction of the bidirectional conduction change-over switch S1; the output end of the control unit MCU is connected to the bidirectional conduction change-over switch S2 and used for controlling the conduction direction of the bidirectional conduction change-over switch S2; the output end of the control unit MCU is connected to the control end of the electronic switch S3.

8. A dual low voltage power supply system for vehicles as claimed in claim 7, wherein: the control unit MCU leads out a CAN communication terminal through the CAN communication module, and the CAN communication terminal is used for being connected to a CAN network of the vehicle.

9. A dual low voltage power supply system for vehicles according to any of claims 1-6, characterized in that: the first power supply positive electrode and the second power supply positive electrode are used for outputting corresponding low-voltage power supply and are used for being respectively connected with electric appliances with corresponding voltages; and during charging, the second power supply positive electrode and the negative electrode of the first storage battery are respectively connected to the positive electrode and the negative electrode of the output end of the vehicle-mounted charging DCDC module.

10. A vehicle, characterized in that: the vehicle employs a dual low voltage power supply system for a vehicle as claimed in any one of claims 1-9 to provide low voltage power to the vehicle.