A battery temperature control system, its operation method, and a battery system

Abstract

The present invention discloses a battery temperature control system, an operation method thereof, and a battery system. The system includes a high-voltage control circuit, a temperature control unit, a controller, a battery control system, and a low-voltage control circuit. One end of the high-voltage control circuit is connected to a power battery for transmitting the high voltage output by the power battery to the temperature control unit. The temperature control unit is used to control the temperature of the medium in the battery temperature control circulation pipeline to achieve the temperature regulation of the power battery. The battery control system is used to control the working state of the system. The low-voltage control circuit is respectively connected to the power battery, the battery control system, and the controller for converting the high voltage input by the power battery into a low voltage to supply the controller and the delivery pump of the battery temperature control circulation pipeline. The controller is used to control the working states of the high-voltage control circuit and the delivery pump. The present invention can ensure that the power battery always operates within a suitable temperature range and exert the maximum performance of the power battery.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy, and particularly to a battery temperature control system, an operation method thereof, and a battery system. Background Art

[0002] With the increasing shortage of traditional energy and the deteriorating environment, countries around the world are vigorously developing new energy vehicles. At present, the development directions of new energy vehicles in various countries (including China) mainly focus on hybrid vehicles and pure electric vehicles. And the power battery is the most important core power component of hybrid vehicles and pure electric vehicles.

[0003] Under normal temperature conditions, the temperature of the power battery will gradually increase after continuous long-term operation until it exceeds the appropriate operating temperature range. To ensure the safety of the battery system, the battery management system (BMS) will limit the vehicle power or even stop the vehicle. And under low temperature conditions, the charge and discharge capabilities of the power battery are also severely restricted. In extremely cold conditions, the power battery cannot even be used, which seriously affects the vehicle operation. Therefore, it is necessary to control the temperature of the battery system. Summary of the Invention

[0004] In view of this, the purpose of the embodiments of the present invention is to provide a battery temperature control system, an operation method thereof, and a battery system, which can ensure that the power battery always operates within the appropriate temperature range and maximize the performance of the power battery system.

[0005] Based on the above purpose, a battery temperature control system provided by the first aspect of the embodiments of the present invention includes a high-voltage control circuit, a temperature control unit, a controller, a battery control system, and a low-voltage control circuit, wherein:

[0006] One end of the high-voltage control circuit is connected to the power battery and is used to transmit the high voltage output by the power battery to the temperature control unit;

[0007] The temperature control unit is used to control the temperature of the medium in the battery temperature control circulation pipeline to realize the temperature regulation of the power battery;

[0008] The battery control system is used to realize the control of the system working state;

[0009] The low-voltage control circuit is respectively connected to the power battery, the battery control system, and the controller, and is used to convert the high voltage input by the power battery into a low voltage to supply the controller and the delivery pump of the battery temperature control circulation pipeline;

[0010] The controller is used to control the working states of the high-voltage control circuit and the delivery pump.

[0011] Optionally, the high-voltage control circuit includes a main relay disposed between the positive electrode of the power battery and the temperature control unit, and the main relay is disconnected or closed under the control of the controller.

[0012] Optionally, the high-voltage control circuit further includes a high-voltage pre-charging unit connected in parallel across the two ends of the main relay, and the high-voltage pre-charging unit includes a pre-charging relay and a pre-charging resistor connected in series.

[0013] Optionally, the high-voltage control circuit further includes a positive relay disposed between the positive electrode of the power battery and the main relay, and a fuse is also disposed between the positive relay and the main relay.

[0014] Optionally, the low-voltage control circuit includes a DC power converter, the DC power converter is connected to the positive electrode of the power battery through a converter positive relay, and the DC power converter is connected to the negative electrode of the power battery through a converter negative relay.

[0015] Optionally, the temperature control unit includes an inverter connected to the high-voltage control circuit and a compressor connected to the inverter; the delivery pump includes a first delivery pump disposed at one end of the battery temperature control circulation pipeline and a second delivery pump disposed at the other end of the battery temperature control circulation pipeline.

[0016] A second aspect of the embodiments of the present invention provides a battery system, including a power battery and the battery temperature control system as described in any one of the above.

[0017] A third aspect of the embodiments of the present invention provides a high-low voltage power-on method for a battery temperature control system, which is applied to the battery temperature control system as described in any one of the above, and includes:

[0018] The battery control system powers on and works at low voltage, generates a wake-up signal and sends it to the low-voltage control circuit;

[0019] The low-voltage control circuit receives the wake-up signal and starts to work, converts the high voltage input from the power battery into a low voltage and supplies it to the controller;

[0020] The controller powers on and works at low voltage, controls the high-voltage control circuit to work, and transmits the high voltage input from the power battery to the temperature control unit.

[0021] Optionally, the low-voltage control circuit includes a DC power converter, a converter positive relay disposed between the DC power converter and the positive electrode of the power battery, and a converter negative relay disposed between the DC power converter and the negative electrode of the power battery. The low-voltage control circuit receiving the wake-up signal and starting to work includes:

[0022] The battery control system determines whether the positive relay of the converter and the negative relay of the converter are in a fault state;

[0023] If not, close the positive relay of the converter and the negative relay of the converter, and the power battery provides high-voltage input for the DC power converter;

[0024] The DC power converter receives the wake-up signal and starts to work.

[0025] Optionally, the high-voltage control loop includes a main relay arranged between the positive electrode of the power battery and the temperature control unit, a high-voltage pre-charge unit connected in parallel at both ends of the main relay, and a positive relay arranged between the positive electrode of the power battery and the main relay. The high-voltage pre-charge unit includes a pre-charge relay and a pre-charge resistor connected in series; wherein, the controller powers on and works at a low voltage, controls the high-voltage control loop to work, and transmits the high voltage input from the power battery to the temperature control unit, including:

[0026] The battery control system determines whether the first high-voltage condition is met;

[0027] If so, close the positive relay and send the state of the positive relay to the controller, and at the same time send a high-voltage request to the controller;

[0028] The controller determines whether the second high-voltage condition is met;

[0029] If so, close the pre-charge relay to perform high-voltage pre-charge until the pre-charge is completed;

[0030] Close the main relay and disconnect the pre-charge relay, and transmit the high voltage input from the power battery to the temperature control unit.

[0031] The fourth aspect of the embodiments of the present invention proposes an operation mode control method for a battery temperature control system, which is applied to the battery temperature control system as described in any one of the above, including:

[0032] Judge the current charge and discharge state of the power battery;

[0033] If in the discharge state, judge whether refrigeration or heating is required according to the situation of the power battery;

[0034] If so, generate a refrigeration instruction or a heating instruction and send it to the temperature control unit, so that the temperature control unit cools or heats the medium in the battery temperature control circulation pipeline;

[0035] Generate a working instruction for the delivery pump and send it to the delivery pump, so that the delivery pump works and enters the self-circulation mode.

[0036] Optionally, the high-voltage control circuit includes a main relay disposed between the positive electrode of the power battery and the temperature control unit, and a positive relay disposed between the positive electrode of the power battery and the main relay; wherein, before determining the current charge and discharge state of the power battery, it further includes:

[0037] After the high and low voltage power-on is completed, the system enters the shutdown operation mode;

[0038] Determine whether the main relay and the positive relay are in the closed state;

[0039] If so, determine the current charge and discharge state of the power battery; otherwise, re-enter the shutdown operation mode.

[0040] Optionally, it further includes:

[0041] During the self-circulation mode, continue to determine whether cooling or heating is required. If so, the temperature control unit cools or heats again;

[0042] After the self-circulation mode ends or a system fault is detected, re-enter the shutdown operation mode.

[0043] The fifth aspect of the embodiments of the present invention proposes a high and low voltage power-off method for a battery temperature control system, which is applied to the battery temperature control system as described in any one of the above, and includes:

[0044] The battery control system determines whether the power-off condition is satisfied;

[0045] If so, generate a high-voltage power-off request and send it to the controller;

[0046] The controller receives the high-voltage power-off request, turns off the temperature control unit and disconnects the high-voltage control circuit;

[0047] The battery control system disconnects the connection between the low-voltage control circuit and the power battery.

[0048] Optionally, the power-off condition includes a system serious fault or a power-off request is received.

[0049] Optionally, the high-voltage control circuit includes a main relay disposed between the positive electrode of the power battery and the temperature control unit, and a positive relay disposed between the positive electrode of the power battery and the main relay; wherein disconnecting the high-voltage control circuit includes:

[0050] The controller disconnects the main relay;

[0051] The battery control system determines whether the main relay has been disconnected, or determines whether the high-voltage power-off request has been sent for a preset first time;

[0052] If so, the battery control system disconnects the positive relay.

[0053] Optionally, after disconnecting the high-voltage control circuit, the method further includes: the battery control system stops sending a wake-up signal to the low-voltage control circuit.

[0054] Optionally, the low-voltage control circuit includes a DC power converter. The DC power converter is connected to the positive electrode of the power battery through a converter positive relay, and the DC power converter is connected to the negative electrode of the power battery through a converter negative relay. Wherein, the battery control system disconnecting the connection between the low-voltage control circuit and the power battery includes: the battery control system disconnecting the converter positive relay and the converter negative relay.

[0055] As can be seen from the above, the battery temperature control system, its operation method, and the battery system provided by the embodiments of the present invention control the conduction and disconnection of the high-voltage control circuit through a controller; when the high-voltage control circuit is conducting, the power battery directly supplies the high voltage required by the temperature control unit; the high voltage input by the power battery is converted into the low voltage required by the controller, the delivery pump, etc. through the low-voltage control circuit, and the battery control system controls the working state of the entire system, such as signal wake-up, power-on and power-off requests, etc. The battery temperature control system described in the embodiments of the present invention can adjust the temperature of the power battery, ensure that the power battery always operates within a suitable temperature range, and maximize the performance of the power battery. Description of the Drawings

[0056] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0057] Figure 1 is a structural block diagram of the battery temperature control system described in the embodiments of the present invention;

[0058] Figure 2 is a structural schematic diagram of the battery temperature control system described in the embodiments of the present invention;

[0059] Figure 3 is a structural block diagram of the battery system described in the embodiments of the present invention;

[0060] Figure 4 is a flowchart of the high-voltage and low-voltage power-on method of the battery temperature control system described in the embodiments of the present invention;

[0061] Figure 5Flowchart of the operation mode control method for the battery temperature control system according to the embodiments of the present invention;

[0062] Figure 6 Flowchart of the high and low voltage power - off method for the battery temperature control system according to the embodiments of the present invention. Detailed implementation manners

[0063] To make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below with reference to specific embodiments and the accompanying drawings.

[0064] It should be noted that all the expressions using "first" and "second" in the embodiments of the present invention are used to distinguish two entities or parameters with the same name but different, so "first" and "second" are only for the convenience of expression and should not be construed as a limitation on the embodiments of the present invention. This will not be elaborated one by one in the subsequent embodiments.

[0065] In recent years, the power battery industry has developed rapidly. The increase in energy density, the reduction in volume, the increase in continuous charge - discharge rate, and the improvement in instantaneous charge - discharge capacity have all greatly improved the performance of the power battery system. At normal temperature, when the battery system works continuously for a long time, especially when it works with high power charge - discharge for a long time, the temperature rise of the battery system gradually increases until it exceeds the appropriate working temperature range. To ensure the safety of the battery system, the battery management system (hereinafter referred to as BMS) will limit the vehicle use power or even stop the vehicle. At low temperature, the charge - discharge capacity of the battery system is also severely restricted. In extremely cold conditions, the battery system cannot even be used, which seriously affects the vehicle operation. Therefore, to ensure the normal operation of the battery system and always give full play to its maximum working performance, it is the development trend of the industry to configure a water - cooling unit system (hereinafter referred to as TMS) for the battery system. TMS meets the functional requirements of heating and cooling the battery system, and can ensure that the battery system always works within the appropriate temperature range and continuously meets the vehicle use requirements. The application, design and control of TMS are the core and key points of the research.

[0066] The first aspect of the embodiments of the present invention proposes a battery temperature control system, as Figure 1 shown, which includes a high - voltage control circuit 1, a temperature control unit 2, a controller 3, a battery control system 4 and a low - voltage control circuit 5, where:

[0067] One end of the high-voltage control loop 1 is connected to the power battery 6, and is used to transmit the high voltage output by the power battery 6 to the temperature control unit 2. The temperature control unit 2 is used to control the temperature of the medium in the battery temperature control circulation pipeline to achieve temperature regulation of the power battery 6. The battery control system 4 is used to achieve control of the system working state. The low-voltage control circuit 5 is respectively connected to the power battery 6, the battery control system 4 and the controller 3, and is used to convert the high voltage input by the power battery 6 into a low voltage to supply the controller 3 and the delivery pump 7 of the battery temperature control circulation pipeline; the controller 3 is used to control the working state of the high-voltage control loop 1 and the delivery pump 7.

[0068] In this embodiment, the power battery 6 can provide a high voltage input for the battery temperature control system, provide power for the operation of the entire battery temperature control system, and also provide power for the operation of the vehicle. When the high-voltage control circuit 1 is turned on, the power battery 6 can provide the temperature control unit 2 with the high voltage input required for its operation. After the temperature control unit 2 is working, it can cool or heat the medium in the battery temperature control circulation pipeline surrounding the power battery 6. The cooled or heated medium circulates in the battery temperature control circulation pipeline under the delivery of the delivery pump 7, so that the low-temperature medium takes away the heat generated by the power battery 6 to avoid the battery temperature being too high, or the high-temperature medium brings appropriate heat to the power battery 6 in a low-temperature state to ensure the normal use of the power battery 6. The battery control system 4 can manage and maintain each power battery 6, and at the same time can realize the control of the working state of the battery temperature control system described in the embodiment of the present invention, such as switching of each operating state of the system, management of the working state of each component in the system, etc. The low-voltage control circuit 5 converts the high voltage input by the power battery 6 into the working voltage required by the controller 3, the delivery pump 7, etc.

[0069] The battery temperature control system described in the embodiment of the present invention controls the conduction and disconnection of the high-voltage control circuit 1 through the controller 3; when the high-voltage control circuit 1 is turned on, the power battery 6 directly supplies the required high voltage to the temperature control unit 2; the high voltage input by the power battery 6 is converted into the low voltage required by the controller 3, the delivery pump 7, etc. through the low-voltage control circuit 5, and the working state of the entire system is controlled by the battery control system 4, such as signal wake-up, power on and off request, etc. The battery temperature control system described in the embodiment of the present invention can adjust the temperature of the power battery 6, ensure that the power battery 6 always works within a suitable temperature range, and give full play to the maximum performance of the power battery 6. Optionally, the medium in the battery temperature control circulation pipeline can be set as a liquid medium or a gas medium as needed, and the delivery pump 7 is also correspondingly designed as a pump adapted to the medium. In a specific embodiment, the medium is water, and the delivery pump 7 can be a water pump.

[0070] In some alternative embodiments, referring to Figure 2 as shown, the high-voltage control circuit 1 includes a main relay K2 disposed between the positive electrode of the power battery 6 and the temperature control unit 2. The main relay K2 is disconnected or closed under the control of the controller 3. The negative electrode of the power battery 6 is directly connected to the temperature control unit 2. After the main relay K2 is closed, a high-voltage circuit is formed between the power battery 6 and the temperature control unit 2, and the power battery 6 can supply power to the temperature control unit 2. Optionally, the main relay K2 can also be a contactor.

[0071] Optionally, the high-voltage control circuit 1 further includes a high-voltage pre-charge unit connected in parallel across the two ends of the main relay K2. The high-voltage pre-charge unit includes a pre-charge relay K1 and a pre-charge resistor R connected in series with each other. When the high-voltage control circuit 1 is turned on, the pre-charge relay K1 is first closed for high-voltage pre-charging. After the pre-charging is completed, the main relay K2 is closed and the pre-charge relay K1 is disconnected to turn on the entire high-voltage control circuit 1, and the power battery 6 supplies power to the temperature control unit 2. In an alternative embodiment, the pre-charge resistor R is a resistor of about 150 Ω.

[0072] Optionally, the high-voltage control circuit 1 further includes a positive relay K0 disposed between the positive electrode of the power battery 6 and the main relay K2. The closing and opening of the positive relay K0 are controlled by the battery control system 4. When the positive relay K0 is closed, the high-voltage circuit on the battery side is turned on. Then the pre-charge relay K1 is closed for high-voltage pre-charging. After the pre-charging is completed, the main relay K2 is closed and the pre-charge relay K1 is disconnected to supply power to the temperature control unit 2. A fuse FUSE is also disposed between the positive relay K0 and the main relay K2 to ensure the safety of the high-voltage circuit.

[0073] In some alternative embodiments, referring to Figure 2 as shown, the low-voltage control circuit 5 includes a DC-DC converter 51 (i.e., DCDC). The DC-DC converter 51 is connected to the positive electrode of the power battery 6 through a converter positive relay K3, and the DC-DC converter 51 is connected to the negative electrode of the power battery 6 through a converter negative relay K4. When both the converter positive relay K3 and the converter negative relay K4 are closed, the power battery 6 can input a high voltage to the DC-DC converter 51, and the DC-DC converter 51 converts the input high voltage into a 24V low voltage required for the operation of the controller 3 and the delivery pump 7.

[0074] In some alternative embodiments, the power battery 6, the positive relay K0, the converter positive relay K3, and the converter negative relay K4 are encapsulated in a high-voltage battery box.

[0075] Optionally, the temperature control unit 2 includes a frequency converter 21 connected to the high-voltage control circuit 1, and a compressor 22 connected to the frequency converter 21. Optionally, the delivery pump 7 includes a first delivery pump 71 provided at one end of the battery temperature control circulation pipeline and a second delivery pump 72 provided at the other end of the battery temperature control circulation pipeline. To avoid insufficient power of one pump, a pump can be provided at each of two places in the battery temperature control circulation pipeline. In an alternative embodiment, when the battery temperature control system according to the embodiment of the present invention realizes battery temperature control by using a water-cooled unit system, the controller 3 selects a TMS controller, the first delivery pump 71 is a TMS water pump, and the second delivery pump 72 is a vehicle water pump.

[0076] Optionally, a first switch F1 is provided between the positive output of the DC power converter 51 and the first delivery pump 71, and a second switch F2 is provided between the negative output of the DC power converter 51 and the second delivery pump 72. When the first switch F1 and the second switch F2 are closed, the low voltage output by the DC power converter 51 can supply power to the first delivery pump 71 and the second delivery pump 72. If it is not necessary for the first delivery pump 71 and the second delivery pump 72 to work or only one of the pumps needs to work, the corresponding switch can be disconnected accordingly, thereby further ensuring the safety and stability of the entire system.

[0077] The second aspect of the embodiment of the present invention proposes a battery system, as Figure 3 shown, including a power battery 6 and a battery temperature control system 99 as described in any one of the above embodiments.

[0078] The battery system described in this embodiment includes a battery temperature control system as described in any one of the above embodiments, and has the same beneficial effects as the battery temperature control system described in any one of the above embodiments, which will not be elaborated here.

[0079] The third aspect of the embodiment of the present invention proposes a high-low voltage power-on method for a battery temperature control system, which is applied to the battery temperature control system as described in any one of the above embodiments, as Figure 4 shown, the method includes:

[0080] Step 101, the battery control system powers on and works at low voltage, generates a wake-up signal and sends it to the low-voltage control circuit.

[0081] In this embodiment, after the battery management system (BMS) of the battery control system powers on and works at low voltage, a wake-up signal TMS_Power+ is given after a preset time delay, such as 100 ms.

[0082] Step 102, the low-voltage control circuit receives the wake-up signal TMS_Power+ and starts to work, converts the high voltage input from the power battery into a low voltage and supplies it to the controller.

[0083] In step 103, the controller powers on and operates at low voltage, controls the high-voltage control circuit to operate, and transmits the high voltage input from the power battery to the temperature control unit.

[0084] In this embodiment, the controller receives the low voltage provided by the low-voltage control circuit and starts to operate. Then, it controls the conduction of the high-voltage control circuit, enabling the power battery to supply power to the temperature control unit. The temperature control unit controls the temperature of the medium in the battery temperature control circulation pipeline to adjust the temperature of the power battery.

[0085] Optionally, the low-voltage control circuit 5 includes a DC power converter 51, a converter positive relay K3 disposed between the DC power converter 51 and the positive electrode of the power battery 6, and a converter negative relay K4 disposed between the DC power converter 51 and the negative electrode of the power battery 6. Among them, the low-voltage control circuit receiving the wake-up signal and starting to operate in step 102 includes:

[0086] In step 201, the battery control system determines whether the converter positive relay and the converter negative relay are in a fault state.

[0087] In step 202, if not, close the converter positive relay and the converter negative relay, and the power battery provides high-voltage input to the DC power converter.

[0088] In step 203, the DC power converter receives the wake-up signal and starts to operate.

[0089] In this embodiment, the battery management system (BMS) of the battery control system needs to perform relay fault detection to determine whether the converter positive relay K3 and the converter negative relay K4 are faulty. If the relay is faulty, a fault is reported. If the relay is fault-free, the converter positive relay K3 and the converter negative relay K4 are closed, enabling the DC power converter 51 to be connected to the power battery 6. After the DC power converter 51 is awakened, it completes power-on at high and low voltages and starts to operate, converting the high voltage input from the power battery 6 into 24V low voltage to supply the controller 3 and the transfer pump 7.

[0090] Optionally, the high-voltage control circuit 1 includes a main relay K2 disposed between the positive electrode of the power battery 6 and the temperature control unit 2, a high-voltage pre-charge unit connected in parallel across the main relay K2, and a positive relay K0 disposed between the positive electrode of the power battery 6 and the main relay K2. The high-voltage pre-charge unit includes a series-connected pre-charge relay K1 and a pre-charge resistor R. Among them, the controller powers on and operates at low voltage in step 103, controls the high-voltage control circuit to operate, and transmits the high voltage input from the power battery to the temperature control unit, including:

[0091] Step 301, the battery control system determines whether the first high-voltage condition is met.

[0092] In this embodiment, the first high-voltage condition means that there are no serious faults in each component such as the battery management system (BMS) and the TMS controller of the battery control system. If there is no fault, step 302 is performed. If there is a fault, a fault report is made.

[0093] Optionally, before performing step 301, it further includes: determining whether the positive relay K0 is faulty. If it is faulty, a fault report is made. If there is no fault, the determination in step 301 is performed. Optionally, the fault determination of the positive relay K0 can also be executed simultaneously with step 301, or between step 301 and step 302.

[0094] Step 302, if so, close the positive relay K0 and send the status of the positive relay K0 to the controller, and at the same time send a high-voltage request to the controller. Otherwise, re-determine whether the first high-voltage condition is met.

[0095] Step 303, the controller determines whether the second high-voltage condition is met.

[0096] In this embodiment, the second high-voltage condition includes whether the positive relay K0 is closed, whether the controller receives a high-voltage request sent by the battery management system (BMS), and whether the entire system has no serious faults. If all the above three conditions are met, that is, the positive relay K0 is closed, the controller receives the high-voltage request and the system has no faults, step 304 is performed. Otherwise, re-determine step 303.

[0097] Step 304, if so, close the pre-charge relay K1 to perform high-voltage pre-charging until the pre-charging is completed. If the pre-charging is unsuccessful, a fault report is made.

[0098] Step 305, after the pre-charging is completed, close the main relay K2 and disconnect the pre-charge relay K1, and transmit the high voltage input from the power battery to the temperature control unit. At this time, the high and low voltage power-on is completed, and the system can start to work.

[0099] The fourth aspect of the embodiments of the present invention proposes a method for controlling the operation mode of a battery temperature control system, which is applied to the battery temperature control system as described in any of the above embodiments. In this embodiment, the operation modes of the battery temperature control system include shutdown operation mode, cooling mode, heating mode and self-circulation mode. The shutdown operation mode is an operation mode in which the high-voltage control circuit 1 and the low-voltage control circuit 5 are both turned on after the high and low voltages are powered on, but the temperature control unit 2 and the delivery pump 7 are not working; the cooling mode is an operation mode in which the temperature control unit 2 cools the medium in the battery temperature control circulation pipeline; the heating mode is an operation mode in which the temperature control unit 2 heats the medium in the battery temperature control circulation pipeline; the self-circulation mode is a mode in which the delivery pump 7 starts to work and the medium flows in the battery temperature control circulation pipeline.

[0100] like Figure 5 As shown, the operation mode control method of the battery temperature control system includes:

[0101] Step 401, determining the current charge and discharge status of the power battery.

[0102] Step 402: If the power battery is in a discharging state, determine whether cooling or heating is required according to the condition of the power battery.

[0103] In this embodiment, the battery control system 4 can monitor the working state of the power battery 6, determine whether the power battery 6 needs to be cooled or heated, and determine whether cooling or heating is currently required according to the working environment and other conditions of the power battery 6. If yes, step 404 is executed, otherwise, whether the cooling or heating conditions are met is re-determined.

[0104] Step 403: If yes, generate a cooling instruction or a heating instruction and send it to the temperature control unit, so that the temperature control unit cools or heats the medium in the battery temperature control circulation pipeline.

[0105] In this embodiment, after determining that cooling or heating is required, a cooling instruction or a heating instruction is generated and sent to the temperature control unit, wherein the cooling instruction or the heating instruction includes information on the temperature and time of cooling or heating. The temperature control unit starts working according to the corresponding cooling instruction or the heating instruction to cool or heat the medium in the battery temperature control circulation pipeline.

[0106] Step 404, generating a delivery pump working instruction and sending it to the delivery pump, so that the delivery pump works and enters a self-circulation mode.

[0107] In this embodiment, the delivery pump can start working after the temperature control unit finishes refrigerating or heating, or can start working after a preset time of refrigerating or heating, or even start working synchronously when refrigerating or heating starts, so as to make the medium in the battery temperature control circulation pipeline flow, and dissipate heat or keep warm for the power battery 6.

[0108] Optionally, the high-voltage control loop includes a main relay K2 arranged between the positive electrode of the power battery 6 and the temperature control unit 2, and a positive relay K0 arranged between the positive electrode of the power battery 6 and the main relay K2; wherein, before judging the current charge and discharge state of the power battery, it further includes:

[0109] Step 501, after the high and low voltages are powered on, the system enters the shutdown operation mode.

[0110] Step 502, judge whether the main relay and the positive relay are both in the closed state.

[0111] Step 503, if so, judge the current charge and discharge state of the power battery; otherwise, re-enter the shutdown operation mode.

[0112] Optionally, it further includes:

[0113] During the self-circulation mode, continue to judge whether refrigeration or heating is still required. If so, the temperature control unit refrigerates or heats again; otherwise, only the self-circulation mode is executed. After the self-circulation mode ends or when a system fault is detected, such as a serious fault of the power battery 6 itself, a fault that the TMS controller determines requires a high-voltage drop, or the battery management system BMS powers off, regardless of the current operating mode, it will re-enter the shutdown operation mode, that is, send an instruction of the shutdown operation mode to the TMS controller.

[0114] The fifth aspect of the embodiment of the present invention proposes a method for powering off the high and low voltages of a battery temperature control system, which is applied to the battery temperature control system described in any of the above embodiments. As Figure 6 shown, the method includes:

[0115] Step 601, the battery control system judges whether the power-off condition is met.

[0116] In this embodiment, when the battery temperature control system is operating normally, it will judge whether the power-off condition is met. Among them, the power-off condition includes: the battery control system BMS receives a power-off request or detects a serious system fault, etc. Among them, the battery control system BMS detecting a system fault includes a serious fault feedback by the TMS controller, a serious fault of the power battery 6 itself, etc.

[0117] Step 602, if so, generate a lower high-voltage request and send it to the controller. Otherwise, the battery management system (BMS) remains in normal operation, and the controller also operates according to the operating mode given by the BMS.

[0118] Step 603, the controller receives the lower high-voltage request, shuts down the temperature control unit, and disconnects the high-voltage control circuit. Optionally, when the controller receives the lower high-voltage request sent by the BMS or determines that communication is lost, it shuts down the temperature control unit and disconnects the high-voltage control circuit.

[0119] Step 604, the BMS disconnects the connection between the low-voltage control circuit and the power battery.

[0120] Optionally, the high-voltage control circuit 1 includes a main relay K2 arranged between the positive electrode of the power battery 6 and the temperature control unit 2, and a positive relay K0 arranged between the positive electrode of the power battery 6 and the main relay K2; where disconnecting the high-voltage control circuit includes:

[0121] Step 701, the controller disconnects the main relay K2.

[0122] Step 702, the BMS determines whether the main relay K2 has been disconnected, or determines whether the lower high-voltage request has been issued for a preset first time.

[0123] In this embodiment, since the pre-charge relay K1 is generally in the off state during normal system operation, for safety reasons, it can be further determined whether the pre-charge relay K1 is in the off state. That is: both the main relay K2 and the pre-charge relay K1 are disconnected, or the first time preset by the system has elapsed since the high-voltage request was sent. At this time, step 703 can be executed; otherwise, the lower high-voltage request is resent. Optionally, the first time is 7s.

[0124] Step 703, if so, the BMS disconnects the positive relay K0.

[0125] Optionally, after disconnecting the high-voltage control circuit in step 603, that is, after disconnecting the positive relay K0, it further includes: the BMS stops sending the wake-up signal TMS_Power+ to the low-voltage control circuit.

[0126] Optionally, the low-voltage control circuit 5 includes a DC power converter 51. The DC power converter 51 is connected to the positive electrode of the power battery 6 through a converter positive relay K3, and the DC power converter 51 is connected to the negative electrode of the power battery through a converter negative relay K4. Among them, the battery control system disconnecting the connection between the low-voltage control circuit and the power battery in step 604 includes: the battery management system BMS disconnecting the converter positive relay K3 and the converter negative relay K4. Optionally, after disconnecting the wake-up signal TMS_Power+, delay for 200 ms and then disconnect the converter positive relay K3 and the converter negative relay K4. At this time, the high-voltage and low-voltage power-off is completed.

[0127] The battery temperature control system, its high-voltage and low-voltage power-on method, operation mode control method, high-voltage and low-voltage power-off method, and battery system according to the embodiments of the present invention can judge whether the power battery needs to be heated or cooled according to the charge and discharge state and temperature state of the power battery, ensuring that the power battery always works within a suitable temperature range and maximizing the performance of the power battery system; the high-voltage and low-voltage power-on and off processes are completed by the cooperation of the BMS and the TMS, and the relay control is reasonably carried out under the requirements of engineering applications; after the heating and cooling modes are ended, the self-circulation mode is executed, and then the shutdown operation mode is entered, and when a serious fault occurs, a control instruction for the shutdown operation mode is directly sent to the TMS; in the high-voltage and low-voltage power-on and off and operation mode control methods, processing measures in case of serious faults are designed, meeting the vehicle use requirements while ensuring the safety of the whole vehicle.

[0128] Those of ordinary skill in the art should understand that: the discussion of any embodiment above is only exemplary, and is not intended to imply that the scope of the present disclosure (including the claims) is limited to these examples; under the idea of the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above, which are not provided in detail for the sake of brevity.

[0129] Additionally, for simplicity of explanation and discussion, and so as not to render the present invention difficult to understand, well-known power / ground connections to integrated circuit (IC) chips and other components may or may not be shown in the provided drawings. Further, the devices may be shown in block diagram form in order to avoid rendering the present invention difficult to understand, and this also takes into account the fact that details of the implementation of such block diagram devices are highly dependent on the platform on which the present invention is to be implemented (i.e., such details should be fully within the understanding of those of ordinary skill in the art). In instances in which specific details (e.g., circuits) are set forth to describe exemplary embodiments of the present invention, it will be apparent to those of ordinary skill in the art that the present invention may be practiced without such specific details or with variations of such specific details. Accordingly, these descriptions are to be regarded as illustrative rather than restrictive.

[0130] Although the present invention has been described in connection with specific embodiments thereof, many alternatives, modifications, and variations will be apparent to those of ordinary skill in the art based on the foregoing description. For example, other memory architectures (e.g., dynamic RAM (DRAM)) may be used with the embodiments discussed.

[0131] Embodiments of the present invention are intended to cover all such alternatives, modifications, and variations that fall within the broad scope of the appended claims. Accordingly, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. A battery temperature control system, characterized in that, It includes a high-voltage control circuit, a temperature control unit, a controller, a battery control system, and a low-voltage control circuit, where: One end of the high-voltage control circuit is connected to the power battery, and is used to transmit the high voltage output by the power battery to the temperature control unit; The temperature control unit is used to control the temperature of the medium in the battery temperature control circulation pipeline to achieve the temperature regulation of the power battery; The battery control system is used to control the working state of the system; The low-voltage control circuit is respectively connected to the power battery, the battery control system, and the controller, and is used to convert the high voltage input by the power battery into a low voltage to supply the controller and the delivery pump of the battery temperature control circulation pipeline; The controller is used to control the working states of the high-voltage control circuit and the delivery pump; The battery control system powers on and works at low voltage, generates a wake-up signal and sends it to the low-voltage control circuit; The low-voltage control circuit receives the wake-up signal and starts to work, converts the high voltage input by the power battery into a low voltage and supplies it to the controller; The controller powers on and works at low voltage, controls the high-voltage control circuit to work, and transmits the high voltage input by the power battery to the temperature control unit.

2. The system according to claim 1, wherein The high-voltage control circuit includes a main relay arranged between the positive electrode of the power battery and the temperature control unit, and the main relay is disconnected or closed under the control of the controller.

3. The system according to claim 2, wherein The high-voltage control circuit further includes a high-voltage pre-charge unit connected in parallel at both ends of the main relay, and the high-voltage pre-charge unit includes a pre-charge relay and a pre-charge resistor connected in series.

4. The system according to claim 2 or 3, characterized in that, The high-voltage control circuit further includes a positive relay arranged between the positive electrode of the power battery and the main relay, and a fuse is also arranged between the positive relay and the main relay.

5. The system according to claim 1, characterized in that The low-voltage control circuit includes a DC power converter, the DC power converter is connected to the positive electrode of the power battery through a converter positive relay, and the DC power converter is connected to the negative electrode of the power battery through a converter negative relay.

6. The system according to claim 1, wherein The temperature control unit includes an inverter connected to the high-voltage control circuit, and a compressor connected to the inverter; the delivery pump includes a first delivery pump arranged at one end of the battery temperature control circulation pipeline and a second delivery pump arranged at the other end of the battery temperature control circulation pipeline.

7. A battery system, characterized in that, It includes a power battery and the battery temperature control system according to any one of claims 1-6.

8. A method for powering on a battery temperature control system at high and low voltages, characterized in that, Applied to the battery temperature control system according to any one of claims 1-6, it includes: The battery control system powers on and works at low voltage, generates a wake-up signal and sends it to the low-voltage control circuit; The low-voltage control circuit receives the wake-up signal and starts to work, converts the high voltage input by the power battery into a low voltage and supplies it to the controller; The controller powers on and works at low voltage, controls the high-voltage control circuit to work, and transmits the high voltage input by the power battery to the temperature control unit; The low-voltage control circuit includes a DC power converter, a converter positive relay disposed between the DC power converter and the positive electrode of the power battery, and a converter negative relay disposed between the DC power converter and the negative electrode of the power battery. The low-voltage control circuit receiving the wake-up signal and starting to work includes: The battery control system determines whether the converter positive relay and the converter negative relay are in a fault state; If not, close the converter positive relay and the converter negative relay, and the power battery provides high-voltage input for the DC power converter; The DC power converter receives the wake-up signal and starts to work.

9. The method according to claim 8, wherein The high-voltage control circuit includes a main relay disposed between the positive electrode of the power battery and the temperature control unit, a high-voltage precharge unit connected in parallel across the main relay, and a positive relay disposed between the positive electrode of the power battery and the main relay. The high-voltage precharge unit includes a precharge relay and a precharge resistor connected in series; wherein, when the controller powers on and works at a low voltage, it controls the high-voltage control circuit to work and transmits the high voltage input from the power battery to the temperature control unit, including: The battery control system determines whether the first high-voltage application condition is met; If so, close the positive relay and send the status of the positive relay to the controller, and at the same time send a high-voltage application request to the controller; The controller determines whether the second high-voltage application condition is met; If so, close the precharge relay to perform high-voltage precharge until the precharge is completed; Close the main relay and open the precharge relay, and transmit the high voltage input from the power battery to the temperature control unit.

10. A control method for the operation mode of a battery temperature control system, characterized in that, Applied to the battery temperature control system according to any one of claims 1-6, including: Judge the current charge and discharge state of the power battery; If in a discharge state, judge whether cooling or heating is required according to the situation of the power battery; If so, generate a cooling instruction or a heating instruction and send it to the temperature control unit, so that the temperature control unit cools or heats the medium in the battery temperature control circulation pipeline; Generate a working instruction for the delivery pump and send it to the delivery pump, so that the delivery pump works and enters the self-circulation mode.

11. The method according to claim 10, wherein The high-voltage control circuit includes a main relay disposed between the positive electrode of the power battery and the temperature control unit, and a positive relay disposed between the positive electrode of the power battery and the main relay; wherein, before judging the current charge and discharge state of the power battery, it further includes: After the high and low voltage power-on is completed, the system enters the shutdown operation mode; Judge whether the main relay and the positive relay are in a closed state; If so, judge the current charge and discharge state of the power battery; otherwise, re-enter the shutdown operation mode.

12. The method according to claim 11, wherein It further includes: During the self-circulation mode, continue to judge whether cooling or heating is required. If so, the temperature control unit cools or heats again; After the self-circulation mode ends or a system fault is detected, re-enter the shutdown operation mode.

13. A method for power-off under high and low voltages of a battery temperature control system, characterized in that, Applied to the battery temperature control system according to any one of claims 1-6, including: The battery control system determines whether the power-off condition is met; If so, generate a lower high-voltage request and send it to the controller; The controller receives the lower high-voltage request, shuts down the temperature control unit and disconnects the high-voltage control circuit; The battery control system disconnects the low-voltage control circuit from the power battery.

14. The method according to claim 13, wherein The power-down condition includes a serious system fault or receiving a power-down request.

15. The method according to claim 13, wherein The high-voltage control circuit includes a main relay arranged between the positive electrode of the power battery and the temperature control unit, and a positive relay arranged between the positive electrode of the power battery and the main relay; wherein the disconnecting of the high-voltage control circuit includes: The controller disconnects the main relay; The battery control system determines whether the main relay has been disconnected, or determines whether the lower high-voltage request has been issued for a preset first time; If so, the battery control system disconnects the positive relay.

16. The method according to claim 13, characterized in that After disconnecting the high-voltage control circuit, it further includes: the battery control system stops sending a wake-up signal to the low-voltage control circuit.

17. The method according to claim 13, wherein The low-voltage control circuit includes a DC power converter, the DC power converter is connected to the positive electrode of the power battery through a converter positive relay, and the DC power converter is connected to the negative electrode of the power battery through a converter negative relay. Wherein, the battery control system disconnecting the low-voltage control circuit from the power battery includes: the battery control system disconnecting the converter positive relay and the converter negative relay.

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