Cooling control circuit in charging process of power battery

Abstract

The utility model discloses a cooling control circuit in the charging process of a power battery, which comprises the power battery, a cooling system, a high-voltage DC / DC (Direct Current / Direct Current), a low-voltage DC / DC and a vehicle control unit, one path of the power battery is connected with the high-voltage DC / DC, and the other path of the power battery is connected with the The output of the high-voltage DC / DC is connected with a compressor of the cooling system; the output of the low-voltage DC / DC is respectively connected with the cooling system, the whole vehicle low-voltage power supply output port and the vehicle-mounted low-voltage storage battery; the high-voltage DC / DC, the low-voltage DC / DC and the cooling system are all in communication connection with the whole vehicle controller through communication wire harnesses. The high-voltage DC / DC and the low-voltage DC / DC are adopted to convert the voltage of the power battery into corresponding high voltage and low voltage respectively, the high voltage is used for providing voltage for a compressor of a cooling system, the low voltage is used for power supply voltage required by the cooling system and other parts of the whole vehicle, and meanwhile, electricity is supplemented for a vehicle-mounted low-voltage storage battery; in the charging process, the cooling system is started, and the problem of circuit coupling caused by electrification or forced work of other parts is avoided.

Description

Technical Field

[0001] The utility model relates to the field of new energy vehicles, and particularly relates to a cooling control circuit for a power battery during the charging process. Background Art

[0002] 1. The charging of power batteries increasingly pursues fast charging, the charging current is getting larger and larger, and the cooling demand is getting higher and higher;

[0003] 2. During the charging process, the vehicle is generally in a powered-off state, resulting in the inability of the original cooling system of the vehicle to work, and the power battery is prone to overheating problems, which affect the charging efficiency and even damage the power battery;

[0004] 3. During the charging process, forcibly starting the cooling system will bring circuit coupling problems such as forced electrification or forced operation of other components. Content of the Utility Model

[0005] The technical problem to be solved by the utility model is the cooling problem caused by the excessive current and long duration during the charging process of the power battery, and at the same time solve the circuit coupling problem caused by forcibly starting the cooling system. To solve the above problems, a cooling control circuit for a power battery during the charging process is provided.

[0006] The purpose of the utility model is achieved in the following way:

[0007] A cooling control circuit for a power battery during the charging process includes a power battery and a cooling system. The circuit further includes a high-voltage DC / DC, a low-voltage DC / DC, and a vehicle controller; one output path of the power battery is connected to the high-voltage DC / DC, and the other output path is connected to the low-voltage DC / DC; the output of the high-voltage DC / DC is electrically connected to the high-voltage components of the cooling system, and the high-voltage DC / DC converts the high voltage of the power battery voltage into the high voltage of the power supply voltage required by the high-voltage components of the cooling system or other components; the output of the low-voltage DC / DC has at least two paths, one path is electrically connected to the low-voltage components of the cooling system, and the other path is used as the output of the vehicle low-voltage power supply and charges the vehicle-mounted low-voltage battery. The low-voltage DC / DC converts the high voltage of the power battery voltage into the 12V or 24V power supply voltage required by the low-voltage components of the cooling system and other components of the vehicle; the high-voltage DC / DC, the low-voltage DC / DC, and the controller of the low-voltage cooling system are all communicatively connected to the vehicle controller through a communication harness.

[0008] The high-voltage components of the cooling system include a compressor; the low-voltage components include the controller of the cooling system.

[0009] The power battery includes a battery pack and a battery management system; the real-time state information of each battery cell in the battery pack is sent to the vehicle controller through the battery management system.

[0010] The vehicle controller is communicatively connected to the on-vehicle terminal, and the on-vehicle terminal is communicatively connected to the monitoring background.

[0011] The low-voltage DC / DC includes two low-voltage output ports. The first output port is connected to the cooling system through a low-voltage harness to provide the required 12V or 24V power supply voltage for the cooling system. The second output port serves as the vehicle's low-voltage power output port and is electrically connected to the on-vehicle low-voltage battery.

[0012] The low-voltage DC / DC includes one low-voltage output port. The output of the low-voltage output port is connected to the cooling system. The low-voltage output port is also connected to the on-vehicle low-voltage battery and the vehicle's low-voltage power output port through a relay, and the relay is connected to the vehicle controller through a low-voltage harness.

[0013] The cooling system includes a compressor, a condenser connected to the compressor through a pipeline. One path of the outlet of the condenser is connected to the compressor through an evaporator expansion valve and an evaporator, and the other path is sequentially connected to the compressor through a heater expansion valve and a heat exchanger; the heat exchanger is used to cool the power battery.

[0014] The beneficial effects of the present utility model: Compared with the prior art, the present utility model uses a high-voltage DC / DC and a low-voltage DC / DC respectively to convert the voltage of the power battery into corresponding high voltage and low voltage. The high voltage is specifically used to provide voltage for the high-voltage components of the cooling system, and the low voltage is specifically used for the power supply voltage required by the cooling system and other components of the vehicle (usually 12V or 24V), and also charges the on-vehicle low-voltage battery; during the charging process, starting the cooling system will not cause problems of other components being electrified or forced to work in circuit coupling. Description of the Drawings

[0015] Figure 1 is the power battery cooling system and circuit of the present utility model.

[0016] Figure 2 is the schematic diagram of the low-voltage DC / DC and the circuit in the present utility model Figure 1 。

[0017] Figure 3 is the schematic diagram of the low-voltage DC / DC and the circuit in the present utility model Figure 2 。 Detailed Embodiments

[0018] The present utility model will be further described in detail below in conjunction with the drawings and specific embodiments.

[0019] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same technical meaning as commonly understood by those of ordinary skill in the technical field to which the present application belongs.

[0020] As Figure 1 shown, a cooling control circuit for a power battery during charging includes a power battery and a cooling system. The circuit further includes a high-voltage DC / DC, a low-voltage DC / DC, and a vehicle controller; one output of the power battery is connected to the high-voltage DC / DC, and the other output is connected to the low-voltage DC / DC; the output of the high-voltage DC / DC is electrically connected to the high-voltage components of the cooling system, and the high-voltage DC / DC converts the high voltage of the power battery voltage into the high voltage of the power supply voltage required by the high-voltage components of the cooling system or other components; the output of the low-voltage DC / DC has at least two paths, one path is electrically connected to the low-voltage components of the cooling system, and the other path is used as the output of the vehicle low-voltage power supply and to charge the vehicle-mounted low-voltage battery. The low-voltage DC / DC converts the high voltage of the power battery voltage into the 12V or 24V power supply voltage required by the low-voltage components of the cooling system and other components of the vehicle; the controllers of the high-voltage DC / DC, the low-voltage DC / DC, and the low-voltage cooling system are all communicatively connected to the vehicle controller through a communication harness.

[0021] The high-voltage components of the cooling system include a compressor; the low-voltage components include the controller of the cooling system.

[0022] The power battery includes a battery pack and a battery management system; the real-time state information of each battery cell in the battery pack is sent to the vehicle controller through the battery management system.

[0023] The vehicle controller is communicatively connected to an in-vehicle terminal, and the in-vehicle terminal is communicatively connected to a monitoring background.

[0024] The low-voltage DC / DC includes 2 low-voltage output ports. The first output port is connected to the cooling system through a low-voltage harness to provide the required 12V or 24V power supply voltage for the cooling system. The second output port is used as the output port of the vehicle low-voltage power supply and is electrically connected to the vehicle-mounted low-voltage battery. As Figure 2 shown, the low-voltage DC / DC has two output ports, namely output port ① and output port ② in the above figure; the vehicle controller controls the low-voltage DC / DC to output low-voltage power from output port ① and output port ② according to different working conditions through a communication harness;

[0025] The low-voltage DC / DC includes a low-voltage output port. The output of the low-voltage output port is connected to the cooling system, and the low-voltage output port is also connected to the vehicle-mounted low-voltage battery and the output port of the vehicle low-voltage power supply through a relay. The relay is connected to the vehicle controller through a low-voltage harness. As Figure 3As shown in the figure, the low-voltage DC / DC has only one output port. A relay is added to the circuit. The vehicle controller can control the relay to close with a low-voltage harness according to the working conditions, so as to output low-voltage power for the whole vehicle.

[0026] The cooling system includes a compressor and a condenser connected to the compressor through a pipeline. One outlet of the condenser is connected to the compressor through an evaporator expansion valve and an evaporator, and the other is connected to the compressor through a heater expansion valve and a heat exchanger in sequence; the heat exchanger is used to cool the power battery.

[0027] The working process of the present utility model is as follows:

[0028] 1. When the vehicle is working normally, after normal power-on, the vehicle controller identifies the temperature information of components such as the drive motor and the power battery (this is the prior art), controls the high-voltage DC / DC to work, and the high-voltage DC / DC drives high-voltage components such as the compressor of the cooling system to work to ensure the cooling of each system of the whole vehicle;

[0029] At the same time, the vehicle controller controls the low-voltage DC / DC to work, provides power from the Figure 2 output port ② in the figure to provide low-voltage power for the whole vehicle and also charge the on-vehicle low-voltage battery; provides power from the Figure 2 output port ① in the figure to provide power for each low-voltage component of the cooling system.

[0030] 2. When the vehicle is charging, there are mainly two working conditions. The driver turns on the on-vehicle low-voltage power supply to charge, such as listening to music in the car, etc.; or only charging without turning on any electrical equipment;

[0031] 2.1 If the driver turns on the on-vehicle low-voltage power supply to charge the power battery, after the vehicle controller identifies this state, it controls the low-voltage DC / DC to work, and both output ports ① and ② work normally to provide low-voltage power for the cooling system and other low-voltage components of the whole vehicle; then, the vehicle controller controls the high-voltage DC / DC to work according to the temperature situation during the battery charging process and the temperature situation of other components of the whole vehicle, and drives the cooling system to operate to realize the cooling of the battery system and other components during the power battery charging process.

[0032] The power battery charging information, the cooling system operation information, the driver operation information, and the status information of other components are all sent to the on-vehicle terminal by the vehicle controller, and then remotely sent to the monitoring background by the on-vehicle terminal to realize the vehicle monitoring during the charging state;

[0033] 2.2 If the power battery is charged when the low-voltage power supply is not turned on in the cab, after the vehicle control unit recognizes this state, it controls the low-voltage DC / DC to work. Only the output port ① works normally and only provides low-voltage power for the cooling system. Then, the vehicle control unit controls the high-voltage DC / DC to work according to the temperature during the battery charging process, drives the cooling system to operate, and realizes the cooling of the battery system during the power battery charging process.

[0034] The power battery charging information, the cooling system operation information, and the driver operation information are all sent to the in-vehicle terminal through the vehicle control unit, and then remotely sent to the monitoring background by the in-vehicle terminal to realize vehicle monitoring during the charging state.

[0035] 3. After identifying the highest cell temperature value inside the power battery (when charging and not charging), the highest temperature value is sent to the vehicle control unit, and the vehicle control unit controls the cooling system to work. During the cooling process, the highest cell temperature value emitted by the battery is still monitored in real time. When it is lower than the threshold, the cooling system operation is stopped. After stopping the cooling system operation, it is still monitored, and so on.

[0036] 4. During driving and charging, in addition to the above functions, the vehicle control unit can also interact with the cooling system controller. When a fault occurs in the cooling system, the information can be sent to the power battery, and the power battery restricts or prohibits vehicle charging to avoid overheating during vehicle charging. The fault information and the battery charging restriction information can be collected and sent to the in-vehicle terminal through the vehicle control unit, and reported to the monitoring background by the in-vehicle terminal.

[0037] The power battery of the present utility model includes a battery pack and a battery management system. The real-time status information of each battery cell (cell) in the battery pack can be sent out through the battery management system. The battery management system (BMS) can forward the information to the vehicle control unit, and the vehicle control unit can control the cooling system to work, realize battery cooling during the charging process, and ensure that high-power and high-current charging can continue.

[0038] The cooling system of the present utility model can be shared with the cooling systems or refrigeration systems of other vehicle components (such as the air-conditioning refrigeration system), or added separately. The high voltage required by the cooling system comes from the high-voltage DC / DC, and the low voltage required comes from the low-voltage DC / DC.

[0039] The high-voltage DC / DC of the present utility model can communicate with the outside and be controlled by the outside. The present utility model Figure 1 is exemplified by the control of the vehicle control unit. The high-voltage DC / DC can convert the power battery voltage (high voltage) into the power supply voltage (high voltage) required by the cooling system or other components.

[0040] The low-voltage DC / DC of the present utility model can communicate with the outside and be controlled by the outside. The present utility model Figure 1The example given is the control of the vehicle controller; the low-voltage DC / DC can convert the power battery voltage (high voltage) into the power supply voltage required by the cooling system and other vehicle components (usually 12V or 24V), and at the same time charge the on-vehicle low-voltage battery;

[0041] During the charging process of the power battery, regardless of whether the vehicle is powered on or not, it does not affect the operation of the cooling system; if the vehicle is powered off, this power battery can regularly wake up the low-voltage DCDC (this is the existing technology of the power battery) to ensure the operation of the charging cooling system, and at the same time ensure real-time monitoring and remote reporting of the charging process data. When the charging control circuit of the power battery wakes up the vehicle to be powered on, the present invention adopts a circuit isolation scheme to ensure that only necessary components (vehicle controller, BMS, high- and low-voltage DCDC, remote vehicle terminal, etc.) are powered on, and other vehicle components (headlights, instrument panel, radio, etc.) are not powered on;

[0042] The vehicle controller in the present invention can monitor the real-time status of all vehicle components in real time, and at the same time monitor the driver's operation requests. According to the real-time status of the components and the driver's operation request signals, it externally controls, identifies vehicle faults, summarizes the real-time status information and fault information of the components, and sends them to the vehicle terminal;

[0043] Compared with a normal pure electric vehicle, the present invention does not add components, uses the vehicle controller, high- and low-voltage DCDC, BMS, remote monitoring system and charging system for information verification, and uses the original vehicle air conditioning system and cooling system to cool the power battery during charging.

[0044] The vehicle terminal of the present invention can remotely send the real-time status information and fault information of the components sent by the vehicle controller to the monitoring background.

[0045] The above are only the preferred embodiments of the present invention. It should be noted that for those skilled in the art, without departing from the overall concept of the present invention, several changes and improvements can still be made, and these should also be regarded as the protection scope of the present invention.

Claims

1. A cooling control circuit for a power battery during charging, comprising a power battery and a cooling system, characterized in that: The circuit further includes a high-voltage DC / DC, a low-voltage DC / DC, and a vehicle controller; one output path of the power battery is connected to the high-voltage DC / DC, and the other output path is connected to the low-voltage DC / DC; the output of the high-voltage DC / DC is electrically connected to the high-voltage components of the cooling system, and the high-voltage DC / DC converts the high voltage of the power battery voltage into the high voltage of the power supply voltage required by the high-voltage components of the cooling system or other components; the output of the low-voltage DC / DC has at least two paths, one path is electrically connected to the low-voltage components of the cooling system, and the other path is used as the output of the vehicle low-voltage power supply and charges the vehicle-mounted low-voltage battery, and the low-voltage DC / DC converts the high voltage of the power battery voltage into the 12V or 24V power supply voltage required by the low-voltage components of the cooling system and other components of the vehicle; the high-voltage DC / DC, the low-voltage DC / DC, and the controller of the low-voltage cooling system are all communicatively connected to the vehicle controller through a communication harness.

2. The cooling control circuit for a power battery during charging according to claim 1, wherein: The high-voltage components of the cooling system include a compressor; the low-voltage components include the controller of the cooling system.

3. The cooling control circuit for a power battery during charging according to claim 1, wherein: The power battery includes a battery pack and a battery management system; the real-time state information of each battery cell in the battery pack is sent to the vehicle controller through the battery management system.

4. The cooling control circuit for a power battery during charging according to any one of claims 1 or 3, characterized in that: The vehicle controller is communicatively connected to the vehicle-mounted terminal, and the vehicle-mounted terminal is communicatively connected to the monitoring background.

5. The cooling control circuit for a power battery during charging according to claim 1, wherein: The low-voltage DC / DC includes 2 low-voltage output ports. The first output port is connected to the cooling system through a low-voltage harness to provide the required 12V or 24V power supply voltage for the cooling system, and the second output port is used as the output port of the vehicle low-voltage power supply and is electrically connected to the vehicle-mounted low-voltage battery.

6. The cooling control circuit for a power battery during charging according to claim 1, characterized in that: The low-voltage DC / DC includes a low-voltage output port. The output of the low-voltage output port is connected to the cooling system, and the low-voltage output port is also connected to the vehicle-mounted low-voltage battery and the output port of the vehicle low-voltage power supply through a relay. The relay is connected to the vehicle controller through a low-voltage harness.

7. The cooling control circuit for the power battery during the charging process according to claim 1, characterized in that: The cooling system includes a compressor, a condenser connected to the compressor through a pipeline. One outlet of the condenser is connected to the compressor through an evaporator expansion valve and an evaporator, and the other outlet is sequentially connected to the compressor through a heater expansion valve and a heat exchanger; the heat exchanger is used to cool the power battery.

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