A protection device, method and vehicle for preventing overcharge and overdischarge of a power battery

Abstract

The application relates to a power battery overcharge and overdischarge protection device, a method and a vehicle; according to collected real-time data, the allowable charging and discharging power of the power battery is calculated by using an intelligent algorithm, when it is detected that the required power of the driver exceeds the allowable charging / discharging power, the target execution torque required to be executed by the motor controller is constrained by a control algorithm; on one hand, the actual power is calculated through the current and voltage values fed back by the battery management system in real time, the required power is adjusted through the difference between the actual power and the required power, and the difference between the target value and the actual value is continuously reduced; on the other hand, the overcharge or overdischarge failure caused by the unexpected load or the motor efficiency deviation is prevented by increasing the open-loop protection threshold; the application can prevent the occurrence of overcharge and overdischarge, improve the safety of the power battery, prevent the occurrence of thermal runaway and improve the service life of the power battery.

Description

Technical Field

[0001] This invention belongs to the field of new energy vehicle technology and relates to a protection device, method and vehicle for preventing overcharging and over-discharging of power batteries. Background Technology

[0002] With the rapid development of the new energy vehicle industry, the safety issues of power batteries in pure electric vehicles and hybrid electric vehicles are particularly prominent. Among these, overcharging / over-discharging is a key factor affecting battery life, performance, and safety. Normally, overcharging / over-discharging is prevented by controlling the motor's output / recovery power during charging / discharging. However, the electrical load on high-voltage components is constantly changing, and the motor itself has inherent precision deviations, leading to frequent overcharging / over-discharging. Therefore, designing an effective overcharge / over-discharge protection method is crucial for the protection of power batteries.

[0003] Patent document CN102104245B provides a method and system for protecting a power battery. The method includes: using an integrated circuit (IC) to detect the voltage of each cell in the power battery, and outputting an alarm protection signal through a pin when the voltage is greater than a predetermined overvoltage threshold or less than a predetermined undervoltage threshold; and using a hardware protection enable circuit to disconnect the charging switch and / or discharging switch of the power battery according to the alarm protection signal, thereby protecting the power battery. The method and system provided by this invention can achieve pure hardware protection against overvoltage and undervoltage in a power battery system with multiple cells connected in series, which is low-cost and highly reliable.

[0004] The aforementioned patent documents are mainly based on hardware circuits, while this invention is mainly based on the vehicle control unit (VCU) control strategy for software protection.

[0005] Patent document CN103594753A discloses a multi-point temperature control protection method for lithium-ion power batteries. The lithium-ion power battery is equipped with multiple thermistors for detecting and measuring the temperature at various points. Each thermistor is connected to a fixed resistor. The protection method includes the following steps: acquiring the values ​​of the thermistors at each measuring point; obtaining the temperature value of each measuring point based on the thermistor values; comparing the temperature values ​​of each measuring point; and taking corresponding processing measures based on the comparison results. An apparatus for implementing the above protection method is also disclosed. The multi-point temperature control protection method and apparatus for lithium-ion power batteries of this invention have the following beneficial effects: timely protection of the battery, extended battery life, slowed battery capacity decay, and timely display of the actual battery temperature.

[0006] The aforementioned patent documents mainly propose a multi-point temperature control protection method for lithium-ion power batteries, focusing on the control of the battery itself; while the present invention is mainly based on the vehicle controller (VCU) control strategy for software protection.

[0007] Patent document CN103825253B discloses a safety control device and method for electric vehicle batteries. The single-cell voltage detection chip of this invention is used to detect the voltage value of each individual battery cell when a fault occurs in the power battery protection circuit. The power battery pack of this invention has a dual protection mechanism of power battery protection circuit and voltage detection chip, and the GSM module can send alarm SMS messages to the user, allowing the user to intervene manually in a timely manner, thereby ensuring the safety of the power battery pack. This invention features good power battery pack safety; users can promptly receive information about power battery pack faults, facilitating timely elimination of safety hazards; simple structure, good stability; and good anti-theft performance.

[0008] The aforementioned patent documents disclose a safety control device and method for electric vehicle batteries, mainly focusing on hardware protection of the battery itself. This invention, however, primarily relies on software protection based on the vehicle control unit (VCU) control strategy. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to overcome the problems existing in the prior art and to provide a protection device, method, vehicle and storage medium for preventing overcharging and over-discharging of power batteries.

[0010] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0011] To solve the above-mentioned technical problems, the present invention is implemented using the following technical solution:

[0012] A protection device for preventing overcharging and over-discharging of a power battery, comprising:

[0013] The closed-loop adjustment module adjusts the demand power in a closed loop by using the difference between the actual power and the demand power, continuously reducing the difference between the target value and the actual value.

[0014] The open-loop control module is used to limit the allowable discharge power and allowable recovery power of the system to prevent overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations.

[0015] A power-torque conversion module is used to convert allowable discharge power and allowable recovery power into allowable discharge torque and allowable recovery torque;

[0016] The driver demand torque calculation module is used to analyze the driver's acceleration demand and convert the accelerator pedal opening and vehicle speed signals into the driver's demand torque.

[0017] The motor torque demand calculation module converts the driver's required torque and motor efficiency into the motor's target execution torque under the current operating conditions.

[0018] The torque arbitration module is used to convert the target execution torque into the execution torque;

[0019] The vehicle status determination module is used to determine the driving status of the vehicle.

[0020] A method for preventing overcharging and over-discharging of a power battery includes the following steps:

[0021] Step 1: Calculate the closed-loop adjustment factor by using the execution deviation between the actual power and the demand power, continuously reduce or even eliminate the difference between the demand power and the actual power, thereby preventing overcharging or over-discharging faults caused by system calculation deviations and inherent deviations of components.

[0022] Step 2: Combining the calculation results from Step 1 with the maximum allowable discharge power and maximum allowable recovery power issued by the battery management system, further limit the allowable discharge power and allowable recovery power available to the current system by setting an open-loop protection threshold to prevent overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations.

[0023] Step 3: Convert the allowable discharge power and allowable recovery power into allowable discharge torque and allowable recovery torque through the power-torque conversion module;

[0024] Step 4: The accelerator pedal opening and vehicle speed signals are converted into the driver's required torque through the driver's required torque calculation module;

[0025] Step 5: Convert the driver's required torque and motor efficiency into the target execution torque using the motor demand torque calculation module;

[0026] Step 6: Convert the target execution torque into the execution torque through the torque arbitration module; when the target execution torque is detected to exceed the allowable discharge torque or the allowable recovery torque, restrict the execution torque sent by the vehicle controller to the motor controller;

[0027] Step 7: Determine the vehicle's driving status through the vehicle status determination module.

[0028] Furthermore, in step one, the difference between the actual power and the required power is adjusted by a PID closed-loop adjustment module. The closed-loop adjustment factor is calculated to constrain the allowable discharge power and allowable recovery power, and to correct the execution torque, thereby reducing or even eliminating the difference between the required power and the actual power, and thus preventing overcharging or over-discharging faults caused by system calculation and component deviations.

[0029] Furthermore, in step two, an open-loop regulation module is used to set a calibrable open-loop protection threshold during the calculation of allowable discharge power and allowable recovery power, thereby further limiting the allowable discharge power and allowable recovery power of the system and preventing overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations.

[0030] Furthermore, the power-torque conversion module described in step three converts the calculated allowable discharge power and allowable recovery power into allowable discharge torque and allowable recovery torque at the current speed.

[0031] Furthermore, the driver demand torque module described in step four converts the accelerator pedal signal at the current vehicle speed into the driver demand torque, which is used to analyze the driver's acceleration demand.

[0032] Furthermore, the motor torque demand calculation module described in step five converts the driver's required torque into the target execution torque under the current operating conditions.

[0033] Furthermore, the torque arbitration module described in step six arbitrates the allowable discharge torque and allowable recovery torque with the target execution torque and various torque requirements, and finally outputs the required torque and recovery torque.

[0034] The vehicle status determination module described in step seven determines the vehicle's driving status by using the brake switch signal, accelerator pedal opening, and vehicle forward direction information.

[0035] A vehicle includes a power battery, a drive motor, a battery management system, a vehicle controller, a motor controller, and a memory for storing one or more programs;

[0036] When the one or more programs are executed by the one or more processors, the one or more vehicle controllers implement the overcharge and over-discharge protection method for the power battery as described above.

[0037] A computer-readable storage medium having a computer program stored thereon that, when executed by a processor, implements the method for preventing overcharging and over-discharging of a power battery as described above.

[0038] Compared with the prior art, the beneficial effects of the present invention are:

[0039] If the power battery experiences overcharging or over-discharging, the system will limit the battery's discharge and charging power if it detects the overcharging or over-discharging. Limiting the charging power will lead to increased vehicle energy consumption; limiting the discharge power will lead to power loss and safety risks such as stalling. If the system does not detect the fault, it may cause safety risks such as decreased battery performance and thermal runaway. This invention can effectively prevent overcharging and over-discharging of the power battery, effectively prevent increased vehicle energy consumption, stalling, thermal runaway and other safety risks, and improve the lifespan of the power battery. Attached Figure Description

[0040] The invention will now be further described with reference to the accompanying drawings:

[0041] Figure 1 This is a flowchart of a method for preventing overcharging and over-discharging of a power battery according to the present invention.

[0042] Figure 2 This is a structural block diagram of a power battery overcharge and over-discharge protection device provided in an embodiment of the present invention;

[0043] Figure 3 This is a schematic diagram of the hardware structure of a vehicle provided in an embodiment of the present invention. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The described embodiments are some, but not all, embodiments of this invention. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this invention, and should not be construed as limiting the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. The embodiments of this invention will be described in detail below with reference to the accompanying drawings.

[0045] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0046] The present invention will now be described in detail with reference to the accompanying drawings:

[0047] This invention provides a protection device to prevent overcharging and over-discharging of a power battery. (See attached document.) Figure 2 ,include

[0048] Modules include closed-loop adjustment, open-loop control, power-torque conversion, torque arbitration, driver torque demand calculation, motor torque demand calculation, and vehicle status determination.

[0049] The closed-loop adjustment module uses the difference between actual power and demand power for PID closed-loop adjustment to calculate the closed-loop adjustment factor; it also uses the difference between actual power and demand power for demand power closed-loop adjustment to continuously reduce the difference between the target value and the actual value, thereby improving the controllability of the actual value.

[0050] An open-loop control module is used to eliminate or prevent overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations. By setting open-loop protection thresholds during the calculation of allowable discharge power and allowable regenerative power, the execution torque sent by the vehicle controller (VCU) to the motor controller (MCU) is further constrained to prevent overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations.

[0051] The power-torque conversion module is used to convert the calculated power into torque at the current speed; and to convert the calculated allowable discharge power and allowable recovery power into allowable discharge torque and allowable recovery torque.

[0052] The torque arbitration module is used to constrain the magnitude of the demand torque and the regenerative torque. It compares the target execution torque calculated by the driver's demand torque module with the allowable discharge torque and allowable regenerative torque converted by the power torque conversion module. When the target execution torque is greater than or equal to the allowable discharge torque or allowable regenerative torque, the demand torque equals the allowable discharge torque, and the regenerative torque equals the allowable regenerative torque. When the target execution torque is less than the allowable discharge torque or allowable regenerative torque, both the demand torque and the execution torque are equal to the target execution torque.

[0053] The driver demand torque module is used to analyze the driver's acceleration demand. It converts the accelerator pedal signal into the driver's demand torque; and obtains the driver's demand torque under the current operating conditions by looking up the accelerator pedal opening and vehicle speed collected by the vehicle control unit (VCU).

[0054] The motor torque demand calculation module converts the driver's required torque into the target execution torque.

[0055] The vehicle status determination module is used to determine the driving status of the vehicle.

[0056] This invention provides a method for overcharge and over-discharge protection of new energy vehicle batteries, the method comprising the following:

[0057] The Battery Management System (BMS) monitors and collects key parameters such as voltage, current, temperature, and SOC (State of Charge) of each individual cell in the battery pack in real time. After internal calculations, it sends the maximum permissible discharge power, maximum permissible regenerative power, current voltage, and current to the vehicle network. Simultaneously, the Vehicle Control Unit (VCU) monitors in real time the maximum permissible discharge power, maximum permissible regenerative power, current voltage, current current, the current speed signal from the Motor Controller Unit (MCU), and signals from within the VCU such as driver-demanded torque, regenerative torque, and accessory power.

[0058] Based on the collected real-time data, the allowable charging power and allowable discharging power of the power battery are calculated using intelligent algorithms. When it is detected that the driver's power demand exceeds the allowable charging power and allowable discharging power, the execution torque sent by the vehicle controller (VCU) to the motor controller (MCU) is constrained by the control algorithm to achieve the purpose of controlling the overcharging or over-discharging of the power battery.

[0059] like Figure 2 As shown, based on the collected real-time data, on the one hand, the allowable discharge power and allowable recovery power are calculated in a timely manner using closed-loop and open-loop adjustment modules, and then converted into allowable discharge torque and allowable recovery torque through the power torque conversion module; on the other hand, the driver's required torque is calculated through the driver's required torque calculation module, and then converted into the target execution torque through the motor required torque calculation module; then, the torque arbitration module arbitrates the allowable discharge torque, allowable recovery torque, target execution torque, and various torque requirements, and limits the execution torque sent by the vehicle controller (VCU) to the motor controller (MCU), effectively avoiding overcharging or over-discharging faults of the power battery.

[0060] like Figure 1 The flowchart shown below illustrates the method for preventing overcharging and over-discharging of a power battery according to the present invention. The specific execution process is as follows:

[0061] The difference between actual power and demand power is adjusted using a closed-loop PID control module. A closed-loop adjustment factor is calculated to reduce the discrepancy between demand and actual power, thereby constraining allowable discharge power and allowable recovery power. The specific implementation method is as follows:

[0062] The actual power (P_out) is calculated by integration based on the current voltage (U_BMS) and current current (I_BMS) fed back in real time by the battery management system (BMS), as shown in formula (1).

[0063] P_out=∫ (U_BMS×I_BMS)×dt Formula (1)

[0064] The required power for the cycle corresponding to the actual power is calculated by using the execution torque (P_opt) issued in the previous few cycles (which can be calibrated according to the actual situation) and the current speed (N_old) of the motor controller, as shown in formula (2).

[0065] P_opt=T_opt×N_old / 9550 Formula (2)

[0066] By adjusting the PID closed-loop control based on the execution deviation between actual power and demand power, the closed-loop adjustment factor is calculated, the magnitude of the execution torque is corrected, and the difference between demand power and actual power is continuously reduced.

[0067] By using an open-loop control module, an open-loop protection threshold is set during the calculation of allowable discharge power and allowable recovery power to further constrain the allowable discharge power and allowable recovery power, preventing overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations. The specific implementation method is as follows:

[0068] By using the open-loop regulation module, an open-loop protection threshold is set during the calculation of allowable discharge power and allowable recovery power (which can be calibrated according to the actual situation of the vehicle) to further prevent overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations.

[0069] The calculated allowable discharge power (P_max_out) and allowable recovery power (P_max_in) are converted into allowable discharge torque (T_max_out) and allowable recovery torque (T_max_in) at the current speed (N_c) by the power-torque conversion module, as shown in formula (3).

[0070] P_max=T_max×N_c / 9550 Formula (3)

[0071] The vehicle control unit (VCU) converts the accelerator pedal signal at the current vehicle speed into the required torque for the driver, using the driver's acceleration needs to analyze the torque demand. The specific implementation method is as follows:

[0072] The vehicle control unit (VCU) obtains the driver's required torque at the current vehicle speed by collecting accelerator pedal opening and vehicle speed signals and using a two-dimensional lookup table (as shown in Table 1, where the horizontal axis represents vehicle speed and the vertical axis represents accelerator pedal opening).

[0073] Table 1

[0074] 0 3.12 3.12 3.12 3.12 -7.35 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 -5.25 2 13.34 13.34 9.98 6.37 5.27 4.73 4.40 4.18 3.91 3.75 3.64 3.51 3.43 3.36 3.34 3.31 3.28 3.27 10 25.91 25.91 25.91 25.91 21.47 17.54 15.00 13.17 10.54 8.33 7.44 6.36 5.71 5.27 4.96 4.73 4.55 4.40 20 44.76 44.76 44.76 44.76 44.76 44.76 38.70 33.59 26.86 22.52 19.39 14.78 11.66 10.24 9.22 8.45 7.86 7.38 25 57.32 57.32 57.32 57.32 57.32 57.32 57.32 50.53 40.13 33.53 28.88 22.51 17.93 14.60 12.96 11.73 10.77 10.00 30 69.89 69.89 69.89 69.89 69.89 69.89 69.89 67.20 53.22 44.33 38.14 29.83 24.19 19.61 16.68 14.98 13.66 12.61 35 82.46 82.46 82.46 82.46 82.46 82.46 82.46 82.46 69.12 57.42 49.31 38.60 31.55 26.21 21.32 19.02 17.25 15.84 40 95.02 95.02 95.02 95.02 95.02 95.02 95.02 95.02 87.98 72.99 62.58 48.96 40.16 33.73 28.50 23.95 21.63 19.78 50 129.58 129.58 129.58 129.58 129.58 129.58 129.58 129.58 129.58 113.63 97.19 75.81 62.31 52.76 45.41 39.35 33.86 30.06 60 176.70 176.70 176.70 176.70 176.70 176.70 176.70 176.70 176.70 168.61 144.07 112.06 92.06 78.14 67.68 59.34 52.33 46.09 70 233.25 233.25 233.25 233.25 233.25 233.25 233.25 233.25 233.25 233.25 204.74 158.89 130.38 110.74 96.17 84.74 75.38 67.39 80 283.52 283.52 283.52 283.52 283.52 283.52 283.52 283.52 283.52 283.52 278.95 216.46 177.26 150.37 130.56 115.17 102.70 92.22 90 333.78 333.78 333.78 333.78 333.78 333.78 333.78 333.78 333.78 333.78 333.78 286.51 234.18 198.29 171.93 151.56 135.14 121.44 100 384.05 384.05 384.05 384.05 384.05 384.05 384.05 384.05 384.05 384.05 384.05 370.08 302.49 255.82 221.62 195.26 174.12 156.58

[0075] The motor torque demand calculation module converts the driver's required torque into the target execution torque. Since the motor itself has efficiency losses (which can be measured using a motor test bench), these losses must be considered during calculation to ensure accurate execution of the target torque. The vehicle control unit (VCU) integrates the motor assembly efficiency map into the corresponding data when calculating the target execution torque required by the motor controller (MCU). The required execution torque for the MCU can be obtained through internal calculation. (For example, if the VCU needs to execute 85 Nm, and the motor efficiency at the current speed is 85%, then the torque required by the MCU is 85 / 0.85, which is 100 Nm.)

[0076] The torque arbitration module arbitrates the allowable discharge torque and allowable recovery torque calculated by the previous modules with the target execution torque and various torque requirements. That is, when the target execution torque is greater than or equal to the allowable discharge torque or allowable recovery torque, the required torque is equal to the allowable discharge torque and the recovery torque is equal to the allowable recovery torque; when the target execution torque is less than the allowable discharge torque or allowable recovery torque, both the required torque and the execution torque are equal to the target execution torque.

[0077] The vehicle status determination module determines the vehicle's driving status by using information such as brake switch signals, accelerator pedal opening, and vehicle direction of travel.

[0078] Example illustration:

[0079] For example, the maximum permissible power output of the battery management system (BMS) of a certain vehicle model is 30kW, the current power consumption of high-voltage components such as air conditioning is 2kW, the current calculated maximum drive capability is 28kW, and the current voltage of the management system (BMS) is 380V. Before the invention was implemented, the maximum drive capability calculated by the vehicle controller (VCU) was 28kW, but in fact the current power of the high-voltage components is 2.5kW. The torque accuracy of the electric drive itself has a deviation of about 3Nm. After conversion by the motor, the actual current is 82.8A, resulting in an over-discharge fault of the battery management system (BMS).

[0080] After adopting this invention, under the same operating conditions, the maximum allowable power output by the battery management system (BMS) is 30kW, and the power consumption of high-voltage components such as air conditioning is 2kW. The maximum allowable discharge power calculated through closed-loop correction becomes 26.5kW. By setting an open-loop protection threshold of 0.5kW, the maximum drive calculated by the vehicle controller (VCU) is limited to 28kW. After conversion by the motor, the actual measured current is 6.7A, and no over-discharge fault of the battery management system (BMS) occurs.

[0081] This invention uses the current voltage (U_BMS) and current current (I_BMS) issued by the battery management system (BMS) to calculate the actual power through integration, which is then used by the vehicle controller (VCU) to calculate the actual power.

[0082] This invention proposes a dynamic calculation method for allowable discharge power and allowable recovery power. The vehicle control unit (VCU) compares the required power of the previous few cycles (calibrated according to the actual vehicle conditions) with the current actual power to calculate the difference between the required power and the actual power. This difference is then used to output a dynamic adjustment factor through a PID algorithm to continuously correct the execution torque of subsequent cycles.

[0083] Demand power refers to the required output torque during acceleration, while regenerative power refers to the energy recovered during deceleration.

[0084] The present invention provides an open-loop protection method for allowable discharge power and allowable recovery power. By setting an open-loop protection threshold based on the maximum allowable discharge power, maximum allowable recovery power and closed-loop adjustment factor of the battery management system (BMS), the maximum allowable discharge power and maximum allowable recovery power are scaled to ensure the safety of allowable discharge power and allowable recovery power.

[0085] This invention provides a vehicle, including a power battery, a drive motor, a battery management system, a vehicle controller 620, a motor controller, and a memory 610;

[0086] The vehicle controller 620 in this vehicle can be one or more. Figure 3 Taking a vehicle controller 620 as an example, the vehicle controller 620 and the memory 610 in the vehicle can be connected via a bus or other means. Figure 2 Taking the bus as an example, it should be noted that in this embodiment, the power battery, battery management system (BMS), and motor controller (MCU) are not connected. Figure 2 As shown in the diagram. Alternatively, the memory 610 can be integrated into the vehicle controller 620; this is not a limitation and can be adjusted according to the actual vehicle conditions.

[0087] The memory 610 in the vehicle serves as a computer-readable storage medium, capable of storing one or more programs. These programs can be software programs, computer-executable programs, or modules, such as the program instructions or modules corresponding to the overcharge and over-discharge protection method for power batteries provided in this embodiment of the invention. For example, modules in an overcharge and over-discharge protection device for power batteries may include closed-loop adjustment, open-loop control, power-torque conversion, torque arbitration, driver-demand torque calculation, motor-demand torque calculation, and vehicle status determination modules. The vehicle controller 620 executes various functional applications and data processing of the device by running the software programs, instructions, and modules stored in the memory 610, thereby implementing the protection method described in the above method embodiments.

[0088] The memory 610 may include a program storage area and a data storage area, wherein the program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created based on the use of the device configured in the device. Furthermore, the memory 610 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some instances, the memory 610 may further include memory remotely configured relative to the vehicle controller 620, which can be connected to the device configured in the device via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0089] The memory 610 stores a computer program, and when the vehicle controller 620 executes the computer program, it performs the following steps:

[0090] Based on the collected real-time data, the allowable charging / discharging power of the power battery is calculated using an intelligent algorithm. When it is detected that the driver's power demand exceeds the allowable charging / discharging power, the target execution torque that needs to be executed is constrained by the vehicle controller (VCU) to the motor controller (MCU) through the control algorithm.

[0091] The actual power is calculated by using the current and voltage values ​​fed back in real time by the BMS. The difference between the actual power and the required power is used to make closed-loop adjustments to the required power, thereby continuously reducing the difference between the target value and the actual value.

[0092] The above-mentioned vehicle can implement the overcharge and over-discharge protection method for power batteries provided in any embodiment of the present invention, and has the corresponding functional modules and beneficial effects for implementing the overcharge and over-discharge protection method for power batteries.

[0093] This invention also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the method for preventing overcharging and over-discharging of power batteries provided in this invention.

[0094] When the one or more programs are executed by the one or more processors, the one or more vehicle control units (VCUs) implement the overcharge and over-discharge protection method for the power battery as described above.

[0095] The computer storage medium of this invention can be any combination of one or more computer-readable media. A computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. For example, a computer-readable storage medium can be, but is not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0096] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media may also be any computer-readable medium other than computer-readable storage media, capable of sending, propagating, or transmitting programs for use by or in connection with an instruction execution system, apparatus, or device.

[0097] Computer program code for performing the operations of this invention can be written in one or more programming languages ​​or a combination thereof. Programming languages ​​include object-oriented programming languages ​​such as Java, Smalltalk, and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0098] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be included within the scope of protection of the present invention. Furthermore, all content not described in detail in this specification is prior art known to those skilled in the art.

Claims

1. A protection device for preventing overcharging and over-discharging of a power battery, characterized in that, include: The closed-loop adjustment module uses the difference between the actual power and the required power to perform PID closed-loop adjustment and calculates the closed-loop adjustment factor. By using the difference between actual power and demand power, a closed-loop adjustment of demand power is made to continuously reduce the difference between the target value and the actual value, thereby improving the controllability of the actual value. The open-loop control module sets an open-loop protection threshold during the calculation of allowable discharge power and allowable recovery power, further constraining the execution torque sent by the vehicle controller (VCU) to the motor controller (MCU), and preventing overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations. A power-torque conversion module is used to convert allowable discharge power and allowable recovery power into allowable discharge torque and allowable recovery torque; The driver demand torque calculation module is used to analyze the driver's acceleration demand and convert the accelerator pedal opening and vehicle speed signals into the driver's demand torque. The motor torque demand calculation module converts the driver's required torque and motor efficiency into the motor's target execution torque under the current operating conditions. The torque arbitration module is used to constrain the magnitude of the required torque and the regenerative torque. It compares the target execution torque calculated by the driver's required torque module with the allowable discharge torque and allowable regenerative torque converted by the power torque conversion module. When the target execution torque is greater than or equal to the allowable discharge torque or allowable regenerative torque, the required torque equals the allowable discharge torque, and the regenerative torque equals the allowable regenerative torque. When the target execution torque is less than the allowable discharge torque or allowable regenerative torque, both the required torque and the execution torque are equal to the target execution torque. The vehicle status determination module is used to determine the driving status of the vehicle.

2. A method for preventing overcharging and over-discharging of a power battery, the method being used in the device as described in claim 1, characterized in that, Includes the following steps: Step 1: Calculate the closed-loop adjustment factor by using the execution deviation between the actual power and the demand power, continuously reduce or even eliminate the difference between the demand power and the actual power, thereby preventing overcharging or over-discharging faults caused by system calculation deviations and inherent deviations of components. Step 2: Combining the calculation results from Step 1 with the maximum allowable discharge power and maximum allowable recovery power issued by the battery management system, further limit the allowable discharge power and allowable recovery power available to the current system by setting an open-loop protection threshold to prevent overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations. Step 3: Convert the allowable discharge power and allowable recovery power into allowable discharge torque and allowable recovery torque through the power-torque conversion module; Step 4: The accelerator pedal opening and vehicle speed signals are converted into the driver's required torque through the driver's required torque calculation module; Step 5: Convert the driver's required torque and motor efficiency into the target execution torque using the motor demand torque calculation module; Step Six: Using the torque arbitration module, the allowable discharge torque and allowable recovery torque calculated by the previous modules are arbitrated with the target execution torque and various torque requirements. That is, when the target execution torque is greater than or equal to the allowable discharge torque or allowable recovery torque, the required torque is equal to the allowable discharge torque and the recovery torque is equal to the allowable recovery torque; when the target execution torque is less than the allowable discharge torque or allowable recovery torque, both the required torque and the execution torque are equal to the target execution torque. Step 7: Determine the vehicle's driving status through the vehicle status determination module.

3. The method for preventing overcharging and over-discharging of a power battery according to claim 2, characterized in that: In step one, the difference between the actual power and the required power is adjusted by PID closed-loop through the closed-loop adjustment module. The closed-loop adjustment factor is calculated to constrain the allowable discharge power and allowable recovery power, and to correct the execution torque, thereby reducing or even eliminating the difference between the required power and the actual power, and thus preventing overcharging or over-discharging faults caused by system calculation deviations and inherent deviations of components.

4. The method for preventing overcharging and over-discharging of a power battery according to claim 2, characterized in that: In step two, the open-loop regulation module sets calibrable open-loop protection thresholds during the calculation of allowable discharge power and allowable recovery power, further limiting the allowable discharge power and allowable recovery power of the system to prevent overcharging or over-discharging faults caused by unexpected loads or motor efficiency deviations.

5. A method for preventing overcharging and over-discharging of a power battery according to claim 2, characterized in that: The power-torque conversion module described in step three converts the calculated allowable discharge power and allowable recovery power into allowable discharge torque and allowable recovery torque at the current speed.

6. The method for preventing overcharging and over-discharging of a power battery according to claim 2, characterized in that: The driver demand torque module described in step four converts the accelerator pedal signal at the current vehicle speed into the driver demand torque, which is used to analyze the driver's acceleration needs.

7. A method for preventing overcharging and over-discharging of a power battery according to claim 2, characterized in that: The motor torque demand calculation module described in step five converts the driver's required torque into the target execution torque under the current operating conditions.

8. A method for preventing overcharging and over-discharging of a power battery according to claim 2, characterized in that: The torque arbitration module described in step six arbitrates the allowable discharge torque and allowable recovery torque with the target execution torque and various torque requirements, and finally outputs the required torque and recovery torque. The vehicle status determination module described in step seven determines the vehicle's driving status by using the brake switch signal, accelerator pedal opening, and vehicle forward direction information.

9. A vehicle, comprising a power battery, a drive motor, a battery management system, a vehicle controller, a motor controller, and a memory, characterized in that: The memory is used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more vehicle controllers implement the method for preventing overcharging and over-discharging of the power battery as described in any one of claims 2 to 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When executed by the processor, the program implements the method for preventing overcharging and over-discharging of the power battery as described in any one of claims 2 to 8.

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