A battery management system and a low-power wake-up device and method thereof

Abstract

The application relates to a battery management system and a low-power consumption awakening device and method thereof, and belongs to the technical field of power battery electric vehicles. The application specifically comprises the following steps: 1) after the vehicle stops running, the number of collection units that last detected faults is determined according to historical fault information detected by each collection unit, and the number is referred to as the fault number; 2) the fault awakening level is determined according to the determined fault number; if the fault number is greater than 0 and less than a set number, the corresponding fault awakening level is the second-level awakening; 3) according to the determined fault awakening level, the battery management system is controlled to awaken in the corresponding awakening mode; if the awakening level is the second-level awakening, the awakening mode is that only the collection unit that detects the fault is controlled to be continuously powered on to awaken, and the rest of the collection units are controlled to be powered on to awaken at a fixed time. The application realizes hierarchical and regional management, prevents the situation of excessive consumption of power battery power, and simultaneously awakens other collection units at a fixed time to realize effective monitoring of various states of all batteries.

Description

Technical Field

[0001] This invention relates to a battery management system and its low-power wake-up device and method, belonging to the field of power battery vehicle technology. Background Technology

[0002] The power battery is the primary power source for pure electric vehicles. To ensure the reliable operation of the power battery, a Battery Management System (BMS) is typically used to monitor its safety status. The BMS includes a master control unit and multiple acquisition units. These acquisition units consist of a high-voltage unit and multiple slave control units. Each slave control unit connects to several batteries and collects status information such as voltage and temperature. The high-voltage unit collects information related to the battery's high voltage (e.g., insulation status). By collecting various status information from the batteries through the BMS, the safety status of the power battery is monitored.

[0003] Even after the vehicle is powered off, the BMS still needs to monitor the battery status for an extended period to prevent malfunctions. The monitoring method involves waking up all data acquisition units after the vehicle is powered off. All these units remain in a continuously powered-on wake-up state, and since they all draw power from the battery, this process undoubtedly consumes a significant amount of battery power, leading to excessive battery drain, high power consumption for the entire battery management system, and unnecessary resource waste. Summary of the Invention

[0004] The purpose of this invention is to provide a battery management system and its low-power wake-up device and method to solve the problem of high power consumption caused by all acquisition units in the battery management system being in a continuous power-on wake-up state when monitoring the battery status while the vehicle is powered off.

[0005] To achieve the above objectives, the present invention includes:

[0006] The present invention provides a low-power wake-up method for a battery management system, comprising the following steps:

[0007] 1) After the vehicle stops running, the number of data collection units that detected the fault in the last time is determined based on the historical fault information detected by each data collection unit. This number is called the number of faults.

[0008] 2) Determine the fault wake-up level based on the number of faults determined in step 1); where, if the number of faults is greater than 0 and less than the set number, the corresponding fault wake-up level is level 2 wake-up.

[0009] 3) Based on the fault wake-up level determined in step 2), control the battery management system to wake up according to the corresponding wake-up method; where, if the wake-up level is level 2 wake-up, the corresponding wake-up method is: control only the acquisition unit that detects the fault to be in continuous power-on wake-up state, and the other acquisition units to be in timed power-on wake-up state.

[0010] This invention provides a low-power wake-up method for a battery management system. After the vehicle stops operating, the number of data acquisition units that detected faults (i.e., the number of faults) is determined based on historical fault information collected by each data acquisition unit. The wake-up level is then determined based on the number of faults. When the number of data acquisition units is small, the wake-up level is level two, meaning only the few data acquisition units that detected faults need to be woken up, and these units remain continuously powered on. The remaining data acquisition units are in a timed power-on wake-up state, meaning they are powered on and woken up according to a set period.

[0011] When only a few acquisition units detect a fault, the method of this invention only continuously wakes up the corresponding acquisition units instead of waking up all the acquisition units. This reduces the power consumption of the power battery while achieving hierarchical and regional management, preventing excessive power consumption of the power battery. At the same time, it periodically wakes up other acquisition units to achieve effective monitoring of the various states of all batteries.

[0012] Furthermore, the fault wake-up level also includes three-level wake-up, with zero faults corresponding to the three-level wake-up. The wake-up method for the three-level wake-up is that both the control acquisition unit and the main control unit are in a timed power-on wake-up state.

[0013] Furthermore, the fault wake-up level also includes Level 1 wake-up, where the number of faults corresponding to Level 1 wake-up is greater than or equal to a set number, and the wake-up method of Level 1 wake-up is: both the control acquisition unit and the main control unit are in a continuous power-on wake-up state.

[0014] After the battery management system was last woken up, the number of data acquisition units corresponding to the historical fault information collected by each data acquisition unit may exceed the set number or no fault may have been detected. Based on these two situations, the wake-up level is further divided into Level 1 wake-up and Level 3 wake-up.

[0015] When the number of data acquisition units identified by historical fault information exceeds the set number, the battery management system will wake up all data acquisition units and main control units, keeping all data acquisition units and main control units continuously powered on. All data acquisition units and main control units will perform fault detection on each battery under their control to further ensure system safety and vehicle safety.

[0016] When the number of data collection units identified by historical fault information is 0, it is only necessary to periodically wake up each data collection unit and the main control unit to ensure continuous monitoring of each battery after the car is powered off, while saving resources as much as possible.

[0017] Furthermore, when the battery management system is at the corresponding wake-up level, if the number of faults detected by the fault acquisition unit changes, the number of faults is re-determined, the corresponding fault level is determined based on the re-determined number of faults, and the battery management system is controlled to wake up according to the re-determined fault level.

[0018] Furthermore, when the battery management system is in the third-level wake-up state, if no fault information is detected by any of the acquisition units within a set number of consecutive timing cycles, the timing cycle time is increased, and the acquisition units and the main control unit are controlled to perform timed power-on wake-up using the increased timing cycle.

[0019] If no fault information is detected after the battery management system performs three-level wake-up a certain number of times, it indicates that the batteries are relatively safe after the car is powered off. In this case, extending the wake-up time for each acquisition unit and the main control unit further reduces the power consumption of the system.

[0020] Furthermore, the wake-up method corresponding to each acquisition unit in the timed power-on wake-up state is as follows: control each acquisition unit to power on and wake up in sequence, and when one acquisition unit is in the power-on wake-up state, the other acquisition units are in the power-off state.

[0021] Furthermore, the wake-up signals for waking up the main control unit and each acquisition unit are electrical signals.

[0022] Furthermore, the set number is 3.

[0023] The present invention also provides a low-power wake-up device for a battery management system, the device including a memory and a processor, the processor executing instructions stored in the memory to implement the low-power wake-up method for a battery management system described above, and to achieve the same beneficial effects as the method.

[0024] The present invention also provides a battery management system, including a main control unit and multiple acquisition units, the multiple acquisition units including a high-voltage unit and multiple slave control units, and also including a memory and a processor. The processor executes instructions stored in the memory to implement the low-power wake-up method of the battery management system described above, and achieves the same beneficial effects as the method. Attached Figure Description

[0025] Figure 1 This is a system component composition diagram of the present invention;

[0026] Figure 2 This is a flowchart of the BMS during the vehicle power-on and operation phase;

[0027] Figure 3 This is a flowchart of the BMS of the present invention during the vehicle power-off phase;

[0028] Figure 4 This is a diagram of the BMS low-power wake-up process of the present invention;

[0029] Figure 5 This is the three-level wake-up transition state diagram of the present invention;

[0030] Figure 6 This is a schematic diagram of the battery management system wake-up device of the present invention. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0032] Battery Management System Example:

[0033] This invention provides a battery management system, such as... Figure 1 As shown, the system consists of a main control unit, slave control units, a high-voltage unit, and a DC-DC power supply. Each slave control unit and high-voltage unit forms a data acquisition unit, and the main control unit is connected to each acquisition unit. The main control unit is used to determine and control the battery's operating status; each slave control unit connects to several batteries and collects status information such as voltage and temperature from these connected batteries; the high-voltage unit collects and detects information related to the battery's high voltage; and the DC-DC power supply provides power conversion for the entire battery management system. During normal vehicle operation, each acquisition unit directly transmits the collected information to the main control unit, which then performs overall monitoring of the battery status.

[0034] Based on the above structure, the present invention adds a state management unit. The state management unit is connected to the main control unit and each slave control unit. It is used to acquire and control the operating status of the entire battery management system according to the information transmitted by the main control unit and all acquisition units after the vehicle stops running.

[0035] During the vehicle's power-on operation phase, after the signal receiving module in the status management unit receives the vehicle signal, such as... Figure 2 As shown, the system detects whether the received vehicle signal is valid. If the vehicle signal is valid, it sequentially wakes up the status management unit, DC-DC power supply, each slave control unit, high-voltage unit, and master control unit, and ensures that the power supply to each component is normal, so that the battery management system can operate normally. The wake-up order of each slave control unit, high-voltage unit, and master control unit can be interchanged, as long as each slave control unit, high-voltage unit, and master control unit has been woken up in sequence.

[0036] After the car stops running, the state management unit detects that the vehicle signal has been powered down and, depending on the scenario, puts various components into low-power sleep mode. For example... Figure 3 As shown, after the vehicle signal is powered off, if the battery management system is operating normally and there are no historical faults, each acquisition unit and the main control unit are in a timed power-on wake-up state. If one or two acquisition units detect a battery fault, the status management unit controls the faulty one or two acquisition units to be in a continuous power-on wake-up state, while the remaining acquisition units and the main control unit are in a timed power-on wake-up state.

[0037] Specifically, such as Figure 4 As shown, after the entire system enters low-power mode, the state management unit first wakes up the DC-DC power supply, which then powers on other acquisition units and the main control unit. This invention divides the wake-up of acquisition units and the main control unit into three levels: Level 1 wake-up, Level 2 wake-up, and Level 3 wake-up. Each acquisition unit controls several connected batteries. If the number of acquisition units involved in the faulty batteries exceeds two, the wake-up level is Level 1. In Level 1 wake-up, all acquisition units and the main control unit need to be woken up to detect all batteries controlled by each acquisition unit. If the number of acquisition units involved in the faulty batteries is 1-2, the wake-up level is Level 2. In Level 2 wake-up, only the acquisition unit that detected the fault needs to be woken up, keeping it continuously powered on. The remaining acquisition units are periodically powered on, i.e., periodically woken up. If the battery is not faulty, the wake-up level is Level 3. In Level 3 wake-up, all acquisition units and the main control unit are periodically woken up.

[0038] The status management unit sequentially wakes up the DC-DC power supply, each acquisition unit, and the main control unit. The DC-DC power supply is woken up using either a physical voltage signal or a CAN signal. The acquisition units and main control unit are woken up using physical voltage signals for power-on. In the first-level wake-up, all BMS units are woken up and powered on, enabling the entire system to detect and diagnose faults. The second-level wake-up wakes up a single acquisition unit, enabling only the corresponding acquisition unit's detection and diagnosis; other acquisition units are woken up periodically according to T1. The third-level wake-up provides power to each unit in different periods (T1, T2), where T1 < T2. If, after multiple consecutive third-level wake-ups according to the T1 period, no faults are found in any unit, the T1 period is adjusted to T2, and wake-up is performed according to the T2 period.

[0039] The following method is used when waking up a low-power wake-up system of battery management, namely, a low-power wake-up method for a battery management system according to the present invention:

[0040] 1) Determine the wake-up level based on historical fault information.

[0041] After the vehicle stops operating, the wake-up level is determined based on the number of data acquisition units involved in the faulty battery detected during the last battery management system wake-up. In addition to the number of data acquisition units involved in the faulty battery detected during the last battery management system wake-up, the wake-up level can also be determined based on historical fault information stored in the battery management system.

[0042] 2) Wake up according to the wake-up level.

[0043] After determining the wake-up level, the battery management system performs the corresponding wake-up. The three wake-up levels can also be interchanged. For example... Figure 5 As shown, for example, if the wake-up level is determined to be level two based on historical fault information, only the 1-2 acquisition units that detected the fault in the previous operation will be woken up, keeping these 1-2 units in a continuous power-on wake-up state, while the remaining acquisition units will be in a timed power-on wake-up state. If only one acquisition unit detected the fault in the previous operation, and another acquisition unit in the timed power-on wake-up state detects a battery fault, the level two wake-up state will remain unchanged. Only when three or more acquisition units detect a battery fault in the level two wake-up state will the level two wake-up state be converted to level one wake-up, waking up all acquisition units and slave control units. If, during the level two wake-up process, the acquisition unit that detected the fault in the previous operation does not detect a fault in this wake-up, and the remaining acquisition units also do not detect a fault, the level two wake-up state becomes level three wake-up, performing timed power-on wake-up on all acquisition units and the master control unit.

[0044] If the current wake-up is determined to be a Level 3 wake-up based on historical fault information, all acquisition units and main control units will be in a timed power-on wake-up state. However, during the detection process, if 1-2 acquisition units detect a battery fault, the Level 3 wake-up will change to a Level 2 wake-up; if 3 or more acquisition units detect a battery fault, the Level 3 wake-up will change to a Level 1 wake-up.

[0045] If the current wake-up is determined to be a Level 1 wake-up based on historical fault information, all acquisition units and main control units will be in a continuous power-on wake-up state. However, if only 1-2 acquisition units detect a battery fault during the detection process, the Level 1 wake-up will become a Level 2 wake-up. If none of the acquisition units and main control units detect a battery fault, the Level 1 wake-up will become a Level 3 wake-up.

[0046] This invention provides a battery management system that monitors the battery after the vehicle is powered off, preventing safety issues caused by battery malfunctions. The system categorizes battery faults based on whether the data acquisition units detect them, with each fault corresponding to a different wake-up level. This allows for tiered and region-based wake-up during battery status monitoring. This avoids the waste of battery power and resources caused by waking up all data acquisition units and the main control unit when only a few units malfunction.

[0047] Example of wake-up method:

[0048] The present invention also provides a low-power wake-up method for a battery management system, which is consistent with the low-power wake-up method for a battery management system described in the system embodiment. Since this method has been clearly described in the battery management system embodiment, it will not be repeated here.

[0049] Example of a wake-up device:

[0050] The present invention also provides a low-power wake-up device for a battery management system, such as... Figure 6 As shown, the device includes an internal bus, a memory, and a processor. The memories communicate and exchange data with each other via the internal bus. The processor can be a microprocessor (MCU), a programmable logic device (FPGA), or other processing devices. The memory can be various types of memory that store information using electrical energy, such as RAM and ROM; it can also be various types of memory that store information using magnetic energy, such as hard disks, floppy disks, magnetic tapes, magnetic core memory, bubble memory, and USB flash drives; it can also be various types of memory that store information using optical methods, such as CDs and DVDs; and of course, it can also be other types of memory, such as quantum memories and graphene memories. The processor executes instructions stored in the memory to implement a low-power wake-up method for a battery management system according to this invention. This method has been clearly described in the battery management system embodiments and will not be repeated here.

Claims

1. A low-power wake-up method for a battery management system, characterized in that, Includes the following steps: 1) After the vehicle stops running, the number of data collection units that detected the fault in the last time is determined based on the historical fault information detected by each data collection unit. This number is called the number of faults. 2) Determine the fault wake-up level based on the number of faults determined in step 1); if the number of faults is greater than or equal to the set number, the fault wake-up level is level 1 wake-up; if the number of faults is greater than 0 and less than the set number, the fault wake-up level is level 2 wake-up; otherwise, the fault wake-up level is level 3 wake-up. 3) Based on the fault wake-up level determined in step 2), control the battery management system to wake up according to the corresponding wake-up method; wherein, the wake-up method corresponding to the first level wake-up is: control the acquisition unit and the main control unit to be in a continuous power-on wake-up state; the wake-up method corresponding to the second level wake-up is: control only the acquisition unit that detected the fault to be in a continuous power-on wake-up state, and the other acquisition units to be in a timed power-on wake-up state; the wake-up method corresponding to the third level wake-up is: control the acquisition unit and the main control unit to be in a timed power-on wake-up state.

2. The low-power wake-up method for a battery management system according to claim 1, characterized in that, When the battery management system is in the corresponding wake-up level, if the number of faults detected by the fault acquisition unit changes, the number of faults is re-determined, the corresponding fault level is determined based on the re-determined number of faults, and the battery management system is controlled to wake up according to the re-determined fault level.

3. The low-power wake-up method for a battery management system according to claim 1 or 2, characterized in that, When the battery management system is in the third-level wake-up state, if no fault information is detected by any of the acquisition units within a set number of consecutive time intervals, the time interval is increased, and the acquisition units and the main control unit are controlled to perform timed power-on wake-up based on the increased time interval.

4. The low-power wake-up method for a battery management system according to claim 1 or 2, characterized in that, The wake-up method for each acquisition unit in the timed power-on wake-up state is as follows: control each acquisition unit to power on and wake up in sequence, and when one acquisition unit is in the power-on wake-up state, the other acquisition units are in the power-off state.

5. The low-power wake-up method for a battery management system according to claim 1, characterized in that, The wake-up signals for the main control unit and each acquisition unit are electrical signals.

6. The low-power wake-up method for a battery management system according to claim 1, characterized in that, The acquisition unit and the main control unit are powered by a DC-DC power supply.

7. The low-power wake-up method for a battery management system according to claim 6, characterized in that, The signal to wake up the DC-DC power supply is either a physical voltage signal or a CAN signal.

8. The low-power wake-up method for a battery management system according to claim 1, characterized in that, The set number is 3.

9. A low-power wake-up device for a battery management system, characterized in that, It includes a memory and a processor, the processor executing instructions stored in the memory to implement the low-power wake-up method of the battery management system according to any one of claims 1-8.

10. A battery management system, comprising a main control unit and multiple acquisition units, wherein the multiple acquisition units include a high-voltage unit and multiple slave control units, characterized in that, It also includes a memory and a processor, the processor executing instructions stored in the memory to implement the low-power wake-up method for the battery management system as described in any one of claims 1-8.

Images