Vehicle brake control method, system, and storage medium

Abstract

The present disclosure provides a vehicle braking control method, system and storage medium, relating to the technical field of vehicle braking control, wherein the method comprises: obtaining a current charging power limit value of a power battery during vehicle driving; comparing the charging power limit value with a power threshold value for predicting a braking power deficiency risk; when the charging power limit value is less than the power threshold value, triggering a first pre-control strategy, controlling the range extender to enter a normal power consumption mode, and controlling the thermal management system to adjust the temperature of the power battery, so that the power battery reaches a first preferred state for entering a braking recovery mode; when the vehicle has a braking demand, dynamically adjusting the recovery torque of the drive motor based on the working condition parameters of the vehicle, so that the vehicle performs braking energy recovery adapted to the current working condition. The method adjusts the state of the power battery by cooperatively controlling the range extender and the thermal management system when the charging power is limited and there is a risk of insufficient vehicle braking power, ensuring driving safety.

Description

Technical Field

[0001] This disclosure belongs to the field of vehicle braking control technology, specifically relating to a vehicle braking control method, system, and storage medium. Background Technology

[0002] During the operation of range-extended vehicles, braking force can come from mechanical braking or regenerative braking. Regenerative braking not only recovers the vehicle's kinetic energy, improving energy efficiency and extending driving range, but it also serves as an effective supplement to mechanical braking, mitigating overheating of mechanical components caused by frequent braking and preventing insufficient braking force due to thermal fade. Therefore, regenerative braking is indispensable for range-extended vehicles, especially heavy-duty range-extended vehicles.

[0003] However, during regenerative braking, if the range-extended vehicle is not equipped with an energy absorption device, such as a resistive grid, and the power battery is not allowed to charge due to power supply limitations, the vehicle control unit (VCU) will be unable to achieve regenerative braking from the motor. In this case, the range-extended vehicle can only rely on mechanical braking, posing a safety hazard due to insufficient braking force.

[0004] To prevent vehicle brake failure, the first approach proposes transferring braking force from the malfunctioning wheel to the functioning wheel. However, this approach fails to consider factors such as vehicle load, gradient, and battery charging limitations. If the battery charging power is limited, the regenerative braking method will fail. The second approach proposes controlling the auxiliary braking device based on vehicle speed and tilt angle when the vehicle is traveling downhill and the air pressure is below a preset threshold. This approach relies entirely on mechanical braking; overheating of the mechanical braking components can lead to brake force attenuation, affecting overall vehicle safety. Summary of the Invention

[0005] This disclosure provides a vehicle braking control method, system, and storage medium, aiming to at least partially solve the technical problem of insufficient vehicle braking force caused by the failure of motor energy recovery braking when the charging power of the power battery is limited.

[0006] At least one embodiment of this disclosure provides a vehicle braking control method applied to a range-extended vehicle having a range extender, a power battery, a drive motor, and a thermal management system. The method includes: during vehicle operation, acquiring a current charging power limit value for the power battery; comparing the charging power limit value with a power threshold used to predict the risk of insufficient braking force; when the charging power limit value is less than the power threshold, triggering a primary pre-control strategy for the risk of insufficient braking force, wherein the primary pre-control strategy is used to control the range extender to enter a normal power consumption mode and control the thermal management system to adjust the temperature of the power battery so that the power battery reaches a first preferred state for entering a regenerative braking mode; and when the vehicle has braking demand, dynamically adjusting the regenerative torque of the drive motor based on the vehicle's operating parameters so that the vehicle performs regenerative braking adapted to the current operating conditions.

[0007] The above solution offers the following technical advantages: Addressing the technical problem of insufficient vehicle braking force due to motor energy recovery braking failure when the power battery charging power is limited, a control method is proposed to effectively avoid insufficient vehicle braking force. This method triggers a first-level pre-control strategy when the charging power limit (where charging power is limited) is less than the power threshold used to predict the risk of insufficient braking force. Through coordinated control of the range extender and thermal management system, the power battery's state is adjusted to the first optimal state for entering the regenerative braking mode. This ensures that the power battery always meets the conditions for motor energy recovery braking, guaranteeing effective motor energy recovery braking, meeting actual driving braking needs, and ensuring driving safety. This method ensures that when the driver demands braking, the drive motor can immediately perform effective energy recovery braking, thereby avoiding braking force loss due to excessively high battery SOC or abnormal temperature, greatly improving the driving braking safety of range-extended vehicles, especially heavy-duty range-extended vehicles, under complex operating conditions.

[0008] The method provided in at least one embodiment of this disclosure further includes: when the state of the power battery reaches the first preferred state, comparing the charging power limit value with the power threshold value again; and when the charging power limit value is still less than the power threshold value, triggering a secondary pre-control strategy for the risk of insufficient braking force, wherein the secondary pre-control strategy is used to control the range extender to continue operating in the normal power consumption mode so that the power battery reaches the second preferred state of preparing to enter the regenerative braking mode.

[0009] The above solution has the following technical effects: after the first-level pre-control strategy is executed, if the power battery state has been optimized but the charging capacity is still insufficient, the second-level pre-control strategy will be further triggered to further reduce the SOC value of the power battery.

[0010] The method provided in at least one embodiment of this disclosure further includes: when the state of the power battery reaches the second preferred state, comparing the charging power limit value with the power threshold value again; and when the charging power limit value is still less than the power threshold value, triggering a three-level pre-control strategy, wherein the three-level pre-control strategy is used to control the range extender to enter an emergency power consumption mode different from the conventional power consumption mode, so as to absorb braking recovery energy, issue an alarm to characterize braking failure, and limit the speed of the vehicle.

[0011] The above solution has the following technical effects: it adopts a three-level pre-control strategy as the final safety backup mechanism, thereby further ensuring the safety of the driver and the vehicle.

[0012] The method provided in at least one embodiment of this disclosure further includes: obtaining the current vehicle speed and load of the vehicle; and determining the power threshold matching the current operating conditions based on the vehicle speed and the load; wherein, as the vehicle speed increases and the load increases, the value of the power threshold increases accordingly.

[0013] The above solution has the following technical effects: the power threshold adopts an adaptive threshold setting method based on vehicle speed and load, making the prediction standard for insufficient braking force risk more scientific and accurate.

[0014] The method provided in at least one embodiment of this disclosure further includes: continuously monitoring the SOC value of the power battery and the temperature of multiple components in the power system of the range-extended vehicle in regenerative braking mode; when any one of the SOC value of the power battery and the temperature of multiple components in the power system of the range-extended vehicle changes, generating a control command for performing a comparison between the charging power limit value and a power threshold for predicting the risk of insufficient braking force, so as to prevent the risk of insufficient braking force of the vehicle in regenerative braking mode.

[0015] The above solution has the following technical effects: it can cope with transient changes during braking through a closed-loop feedback mechanism, and prevent sudden interruption of energy recovery due to power limitation caused by sudden changes in battery state such as a sudden rise in temperature.

[0016] In at least one embodiment of the method provided in this disclosure, the primary pre-control strategy includes: determining a first SOC threshold based on the power threshold; obtaining the SOC value of the power battery and the temperature of the power battery; in response to the SOC value of the power battery being greater than the first SOC threshold, controlling the range extender to enter a normal power consumption mode, so as to regulate the SOC value of the power battery to below the first SOC threshold through the power consumption of the range extender; and in response to the temperature of the power battery exceeding a set temperature range used to characterize suitability for entering a regenerative braking mode, controlling the thermal management system to adjust the temperature of the power battery, so as to regulate the temperature of the power battery to the set temperature range.

[0017] The above solution has the following technical effects: it can coordinate the control of the temperature and SOC value of the power battery, ensuring that the power battery can quickly enter the first preferred state, so as to create conditions for more efficient regenerative braking.

[0018] In at least one embodiment of the method provided in this disclosure, the secondary pre-control strategy includes: determining a second SOC threshold based on the first SOC threshold; and controlling the range extender to continue operating in a normal power consumption mode so that the SOC value of the power battery is adjusted to below the second SOC threshold through the power consumption of the range extender; wherein the first SOC threshold is greater than the second SOC threshold.

[0019] The above solution has the following technical effects: when it is confirmed that the primary strategy is insufficient to remove the power limit of the power battery, more aggressive discharge measures will be taken to ensure safety.

[0020] In at least one embodiment of the method provided in this disclosure, the range extender includes an engine and a generator, and the three-level pre-control strategy includes: controlling the range extender to enter an emergency power consumption mode, wherein in the emergency power consumption mode, the engine enters an in-cylinder braking state, and the generator reverse-drives the engine to absorb braking energy; issuing an alarm to characterize a braking failure; and classifying the vehicle's speed limit based on the vehicle's current load, wherein different load ranges correspond to different target speed limit values.

[0021] The above solution offers the following technical advantages: it employs efficient and reliable physical energy absorption methods, enabling the direct dissipation of braking energy generated by the drive motor without relying on a power battery. Furthermore, it balances transportation efficiency and safety requirements under different operating conditions through tiered speed limiting.

[0022] At least one embodiment of this disclosure also provides a vehicle braking control system applied to a range-extended vehicle having a range extender, a power battery, a drive motor, and a thermal management system, comprising: an acquisition unit configured to acquire a current charging power limit value of the power battery during vehicle operation; a preprocessing unit configured to compare the charging power limit value with a power threshold used to predict the risk of insufficient braking force; a risk pre-control unit configured to trigger a first-level pre-control strategy for the risk of insufficient braking force when the charging power limit value is less than the power threshold, wherein the first-level pre-control strategy is used to control the range extender to enter a normal power consumption mode and control the thermal management system to adjust the temperature of the power battery so that the power battery reaches a first preferred state for entering a regenerative braking mode; and a braking control unit configured to dynamically adjust the regenerative torque of the drive motor based on the vehicle's operating parameters when braking is required, so as to perform safe braking on the vehicle.

[0023] At least one embodiment of this disclosure also provides a storage medium storing a program or instructions, wherein the program or instructions, when executed by a processor, implement the steps of the method provided in any embodiment of this disclosure.

[0024] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this disclosure, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the powertrain composition of range-extended vehicles in related technologies; Figure 2 A flowchart of a vehicle braking control method provided for at least one embodiment of this disclosure; Figure 3 A flowchart of a primary pre-control strategy provided in at least one embodiment of this disclosure; Figure 4 A flowchart of a recovery torque control scheme provided in at least one embodiment of this disclosure; Figure 5 A flowchart of another vehicle braking control method provided for at least one embodiment of this disclosure; Figure 6 A flowchart of yet another vehicle braking control method provided for at least one embodiment of this disclosure; Figure 7 A flowchart of yet another vehicle braking control method provided for at least one embodiment of this disclosure; Figure 8 A flowchart of yet another vehicle braking control method provided for at least one embodiment of this disclosure; Figure 9 A flowchart illustrating an example of a vehicle braking control method provided in at least one embodiment of this disclosure; Figure 10 A structural block diagram of a vehicle braking control system provided in at least one embodiment of this disclosure; Figure 11 A structural block diagram of a program product provided for at least one embodiment of this disclosure.

[0027] Figure label: 1- Power battery; 2- Range extender; 3- Vehicle controller; 4- Brake pedal; 5- Motor controller; 6- Drive motor; 7- Gearbox; 8- Axle; 21- Engine; 22- Generator; 100- Vehicle braking control system; 101- Acquisition unit; 102- Preprocessing unit; 103- Risk pre-control unit; 104- Braking control unit; 201- Processor; 202- Memory; 203- Input device; 204- Output device. Detailed Implementation

[0028] The present disclosure will now be described in further detail with reference to the accompanying drawings and embodiments. It should be particularly noted that the following embodiments are for illustrative purposes only and do not limit the scope of the disclosure. Similarly, the following embodiments are only some, not all, embodiments of the present disclosure, and all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this disclosure.

[0029] The terms "first," "second," and "third" used in the embodiments of this disclosure are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first," "second," and "third" may explicitly or implicitly include at least one of that feature.

[0030] In the description of this disclosure, "multiple" means at least two, such as two or three, unless otherwise expressly and specifically limited.

[0031] In this disclosure, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0032] The terms “comprising” and “having”, and any variations thereof, used in this disclosure are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or components inherent to such processes, methods, products, or devices.

[0033] The term "thermal management system" in this disclosure is abbreviated as TMS.

[0034] The term "battery state of charge" in this disclosure is abbreviated as SOC.

[0035] The term "battery health status" in this disclosure is abbreviated as SOH. The term "vehicle controller" in this disclosure is abbreviated as VCU.

[0036] The term "charging power limit value" in this disclosure embodiment, also known as the allowable charging power limit value, refers to the maximum charging power that the power battery is currently allowed to receive, which can be calculated by the battery management system based on the power battery's current SOC value, operating temperature, and SOH value, and other core operating parameters.

[0037] Figure 1 This is a schematic diagram of the powertrain composition of range-extended vehicles in related technologies. For example... Figure 1As shown, the power system of the range-extended vehicle includes a power battery 1, a range extender 2, a vehicle controller 3, a brake pedal 4, a motor controller 5, a drive motor 6, a transmission 7, and an axle 8. The range extender 2 includes an engine 21 and a generator 22. The power battery 1 is electrically connected to both the range extender 2 and the motor controller 5. The range extender 2 is used to generate electricity when the power battery 1 is low, either to replenish the power battery 1 or to directly power the drive motor 6. The vehicle controller 3 is signal-connected to both the brake pedal 4 and the motor controller 5, and is used to receive driver commands and coordinate the operation of various components. The motor controller 5 controls the output torque of the drive motor 6. The drive motor 6 is connected to the axle 8 via the transmission 7, ultimately driving the range-extended vehicle.

[0038] Test results show that when the charging power of the power battery 1 is limited, the regenerative braking method using the electric motor will fail. Overheating of the mechanical braking system can lead to a decrease in braking force, thus affecting overall vehicle driving safety. Furthermore, the braking performance of range-extended vehicles is worse under full load conditions than under no-load conditions. Therefore, regenerative braking using the electric motor plays a crucial role in improving braking performance, and its failure must be prevented.

[0039] For range-extended mining trucks, when the vehicle's braking relies solely on mechanical braking and regenerative braking from the electric motor, it is essential to ensure that the drive motor can perform regenerative braking at any time. If the vehicle is not equipped with energy absorption devices, such as resistive grids, the power battery must always maintain a certain charging capacity to accommodate the recovered energy. The charging power limit of the power battery is mainly constrained by the State of Charge (SOC) value and temperature: higher charging power is allowed at low SOC values, while charging power decreases at high SOC values. Excessively high or low temperatures will limit the charging power.

[0040] To address the technical problem of insufficient vehicle braking force caused by the failure of motor energy recovery braking when the charging power of the power battery is limited, this disclosure proposes a control method that can effectively avoid insufficient vehicle braking force. When the charging power limit value (where the charging power is limited) is less than the power threshold used to predict the risk of insufficient braking force, this method triggers a first-level pre-control strategy. Through coordinated control of the range extender and thermal management system, the state of the power battery is adjusted to the first preferred state for entering the braking recovery mode. This ensures that the power battery always meets the conditions for motor energy recovery braking, guaranteeing effective motor energy recovery braking, meeting actual vehicle braking needs, and ensuring driving safety. This method ensures that when the driver generates braking demand, the drive motor can immediately perform effective energy recovery braking, thereby avoiding the loss of braking force caused by excessively high battery SOC or abnormal temperature, greatly improving the driving braking safety of range-extended vehicles, especially heavy-duty range-extended vehicles, under complex operating conditions.

[0041] Based on this, the method disclosed herein, after the power battery is depleted to below the second SOC threshold and the power battery temperature is within the set temperature range used to characterize the suitability for entering the regenerative braking mode, determines that the charging power limit value of the power battery is still less than the preset power threshold. In this case, the VCU controls the range extender to deplete power urgently to absorb the energy from the regenerative braking, and at the same time reports a braking fault and limits the vehicle speed to further ensure the safety of the driver and the range-extended vehicle.

[0042] Based on this, the method disclosed herein obtains a power threshold for predicting the risk of insufficient braking force by looking up a table based on real-time vehicle speed and load. At the same time, the first SOC threshold is obtained by calculating the amount of energy recovered based on the power threshold and dynamically back-calculating the value that the SOC value needs to be reduced to, so that the SOC of the power battery is within a reasonable range suitable for entering the braking regeneration mode.

[0043] Figure 2 This is a flowchart illustrating a vehicle braking control method provided for at least one embodiment of the present disclosure. The method is applicable to any range-extended vehicle having a range extender, a power battery, a drive motor, and a thermal management system. Figure 2 As shown, the method may include the following steps S10-S40 to ensure braking safety.

[0044] Step S10: During vehicle operation, obtain the current charging power limit value of the power battery.

[0045] Step S20: Compare the charging power limit value with the power threshold used to predict the risk of insufficient braking force.

[0046] Step S30: When the charging power limit is less than the power threshold, a first-level pre-control strategy for the risk of insufficient braking force is triggered. The first-level pre-control strategy is used to control the range extender to enter the normal power consumption mode and control the thermal management system to adjust the temperature of the power battery so that the power battery reaches the first preferred state for entering the regenerative braking mode.

[0047] Step S40: When the vehicle has braking requirements, the recovery torque of the drive motor is dynamically adjusted based on the vehicle's operating parameters so that the vehicle can perform braking energy recovery that is adapted to the current operating conditions.

[0048] It should be noted that the above scheme does not impose restrictions on the strategy when the charging power limit is equal to the power threshold. When the charging power limit is equal to the power threshold, an appropriate control strategy can be selected based on the vehicle calibration requirements and the degree of aging and degradation of the power battery. This strategy can either trigger the first-level pre-control strategy or choose not to trigger it, maintaining the vehicle's normal operating state. Step S40 can be further configured to execute when the charging power limit is greater than the power threshold.

[0049] In the above scheme, this disclosure does not limit the method for obtaining the charging power limit value in step S10. In practical application scenarios, the charging power limit value can be obtained through the BMS, or calculated by the vehicle controller based on operating parameters such as the current remaining charge, health status, and operating temperature of the power battery. Alternatively, it can be obtained from the cloud-based vehicle service platform via the onboard communication unit, based on the pre-calibrated charging power limit value for the corresponding vehicle model under the current operating conditions. When executing step S10, the system can flexibly select an appropriate charging power limit value acquisition method according to the vehicle's hardware configuration, computing power level, and requirements for parameter acquisition accuracy.

[0050] In the above scheme, this disclosure does not limit the power threshold determination scheme in step S20. In practical application scenarios, in addition to the pre-set scheme or the scheme described in the following embodiments, it can also be adaptively calculated based on any one or more parameters from the nominal capacity of the power battery, the current health status, the ambient temperature, and the vehicle's historical operating data. Alternatively, it can be pre-calibrated through bench testing and stored in the vehicle control unit for direct retrieval. The power threshold setting can also be flexibly adjusted according to the vehicle's priority requirements for thermal runaway prevention level and braking energy recovery efficiency. It can be set to a single fixed threshold or multiple sets of differentiated thresholds for different operating scenarios. The system can select the appropriate power threshold according to actual needs to achieve a good balance between thermal runaway risk prevention effect and braking energy recovery efficiency. When the system executes step S20, it can flexibly select the corresponding power threshold determination scheme according to the vehicle's scenario adaptation requirements, hardware configuration, and prevention priority target to adapt to the actual use needs of different types of new energy vehicles.

[0051] In the above scheme, this disclosure does not limit the primary pre-control strategy in step S30. In practical application scenarios, in addition to the scheme described in the following embodiments, it can also be adaptively matched and generated based on any one or more parameter combinations among the current vehicle braking request intensity, the current charging capacity margin of the power battery, the stability state of the vehicle driving, and the current thermal runaway risk level of the vehicle. Alternatively, multiple sets of control strategy mapping tables can be pre-calibrated according to the dynamic characteristics of different vehicle models and stored in the vehicle controller, and the corresponding strategy can be directly retrieved and executed according to the current vehicle operating scenario. The triggering and execution of the primary pre-control strategy can also be flexibly adjusted according to the thermal runaway prevention priority set in advance by the vehicle. It can either only adjust the gradient limit of the upper limit power of braking energy recovery, or simultaneously trigger pre-conditioning of power battery cooling and pre-warning of thermal runaway risk, etc., to complete the preparation work for thermal runaway prevention in advance while ensuring the smoothness of vehicle braking and energy recovery efficiency. When the system executes step S30, it can select an appropriate primary pre-control strategy based on the multi-source perception data currently acquired by the vehicle to ensure that the braking distance meets national safety requirements and the braking process is smooth and without jerking.

[0052] In the above scheme, this disclosure does not limit the type of operating condition parameters and the regenerative torque control scheme in step S40. In practical application scenarios, in addition to the schemes described in the following embodiments, the operating condition parameters may also include any one or more combinations of the following: vehicle current speed, brake pedal opening, SOC value, maximum single cell temperature of the power battery, temperature range of single cells of the power battery, thermal management system operating status parameters, vehicle longitudinal acceleration, ambient temperature, brake master cylinder pressure, steering wheel angle, and vehicle yaw rate. The regenerative torque control scheme may also calculate the optimal upper limit of regenerative torque in real time based on the perception results of multi-sensor fusion, or it may pre-calibrate a mapping table of regenerative torque ranges under different operating conditions. The vehicle controller only needs to directly match and call the corresponding torque control range according to the currently collected parameters, which can be adapted to vehicle controllers with different computing power specifications. The regenerative torque control scheme may also include: when it is determined that the vehicle has a braking demand and the current mechanical braking thermal fade risk is in the low-risk range, gradually lowering the upper limit of the regenerative torque, and simultaneously increasing the braking force output ratio of the mechanical braking system to ensure that the vehicle deceleration meets the driver's braking request and that there is no problem of insufficient braking capacity or braking jerking. When the system executes step S40, it can select a suitable recovery torque control scheme according to the actual needs of the vehicle. Under the premise of ensuring braking safety and meeting the driver's deceleration needs, it can retain a reasonable proportion of braking energy recovery quota as much as possible, thereby improving the energy utilization rate and range performance of the whole vehicle, avoiding unnecessary energy waste, and ultimately achieving a balance between the safety of power battery thermal runaway prevention and control and the energy economy of the whole vehicle.

[0053] The method provided in at least one embodiment of this disclosure is applicable to any existing application scenario of range-extended vehicles where insufficient braking force needs to be avoided. For example, it can be applied to range-extended urban SUVs equipped with high-energy-density ternary lithium batteries. Users of these vehicles often experience frequent starts and stops in high-speed, continuous downhill driving or congested urban traffic. Continuous regenerative braking causes the battery to continuously charge and generate heat, which can easily lead to thermal runaway. The method of this disclosure can effectively balance energy recovery efficiency and thermal safety. It can also be applied to range-extended logistics delivery trucks used in urban operations. These vehicles experience frequent starts and stops daily, requiring high levels of range economy and driving safety. The method of this disclosure can improve energy utilization while meeting the driver's braking needs and preventing the risk of thermal runaway from the battery.

[0054] In some embodiments, Figure 2Based on the proposed solution, to accurately obtain the charging power limit value, the charging power limit value in step S10 can be obtained by the battery management system. When the charging power of the power battery is limited, the charging power limit value at that time can be obtained. Vehicles need to limit the charging power of the power battery under various operating conditions, including but not limited to: when the power battery is at risk of thermal runaway, or when the SOC value is close to the full charge threshold to prevent overcharging, or when potential faults such as abnormal cell voltage or decreased insulation performance are detected in the power battery.

[0055] In some embodiments, Figure 2 Based on the proposed solution, the operating parameters in step S40 include road gradient and load. Road gradient can be calculated in advance using vehicle positioning information combined with road elevation data from a navigation electronic map, or it can be obtained in real-time through filtered data collected by the vehicle's wheel-end acceleration sensors. The road gradient directly determines the basic braking force required for the vehicle during downhill coasting. The greater the road gradient, the greater the vehicle's own coasting acceleration, and the higher the basic braking force required during driving. By using road gradient data, the intensity and duration of the vehicle's subsequent braking needs can be predicted in advance. Combined with the current charging power limit of the power battery, the torque distribution ratio between mechanical braking and energy recovery braking can be dynamically adjusted in advance, avoiding the risk of thermal runaway caused by rapid battery temperature rise during continuous downhill driving or frequent start-stop operations in urban areas. Load can be collected by a load sensor or estimated by fitting and analyzing the driving torque and acceleration data during the vehicle's start-up phase. The total vehicle load directly determines the vehicle's total inertia during driving and the total amount of kinetic energy that can be recovered during braking. At the same vehicle speed, the greater the load, the higher the total braking torque required to achieve the specified braking deceleration, and the more braking kinetic energy can be recovered. By incorporating load and road gradient into the torque adjustment process, it is possible to ensure that the braking effect meets safety regulations, maximize the energy recovery ratio within the limits of the power battery charging capacity, and avoid the problem of insufficient energy recovery torque under heavy loads leading to excessive braking distance, thereby further improving the safety and economy of vehicle braking under different operating conditions.

[0056] Figure 3 A flowchart illustrating a primary pre-control strategy provided for at least one embodiment of this disclosure. Figure 2 Based on the existing solution, in order to address charging limitations, such as... Figure 3 As shown, the primary pre-control strategy in step S30 may further include the following sub-steps S301-S304.

[0057] Sub-step S301: Determine the first SOC threshold based on the power threshold.

[0058] Sub-step S302: Obtain the SOC value and temperature of the power battery.

[0059] Sub-step S303: In response to the SOC value of the power battery being greater than the first SOC threshold, the range extender is controlled to enter the normal power consumption mode so that the SOC value of the power battery is adjusted to below the first SOC threshold through the power consumption of the range extender.

[0060] Sub-step S304: In response to the power battery temperature exceeding the set temperature range used to characterize the suitability for entering the regenerative braking mode, control the thermal management system to adjust the power battery temperature so that the power battery temperature is regulated to the set temperature range.

[0061] It should be noted that the normal power consumption mode refers to the VCU controlling the generator to operate in speed control mode, where the generator reverse-drives the engine. The generator, as a power-consuming device, consumes electrical energy, causing the SOC value of the power battery to decrease. Sub-steps S303 and S304 can be executed synchronously.

[0062] In this process, sub-steps S301-304 are used to perform preliminary pre-adjustment of the power battery state. This allows the power battery to be pre-adjusted to the optimal working state for regenerative braking before conditions such as long downhill slopes and frequent start-stop operations, which require a large amount of regenerative braking energy. This not only reserves sufficient charging capacity to accommodate the regenerated braking energy, but also controls the risk of battery overheating within a safe range through temperature regulation. This avoids the power battery being forced to reduce or even shut down the energy regeneration function due to excessively high SOC or temperature exceeding a reasonable range during subsequent braking, which could lead to excessive mechanical braking burden and brake fade safety issues during long downhill slopes. At the same time, it also ensures that the braking energy that meets the regeneration conditions is well utilized, balancing the braking safety of the vehicle and the overall driving range economy.

[0063] The above solution not only considers adjustments to the SOC (State of Charge) value but also simultaneously addresses limitations related to battery temperature, ensuring that the power battery can quickly enter its optimal operating range. Compared to control methods that rely solely on a single dimension, this collaborative control approach is more efficient and can remove charging limitations for the power battery in most cases.

[0064] In some embodiments, Figure 3 Based on the scheme, in order to obtain the first SOC threshold that matches the current working condition, sub-step S301 may further include the following sub-steps S301a-S301d.

[0065] Sub-step S301a: Calculate the expected amount of electricity to be recovered based on the power threshold corresponding to the charging power limit value.

[0066] Sub-step S301b: Determine the target SOC threshold that the power battery needs to be reduced to based on the battery capacity.

[0067] Sub-step S301c: Obtain the vehicle's current brake pedal opening and road gradient.

[0068] Sub-step S301d: The target SOC threshold is weighted and corrected based on the brake pedal opening and road slope to determine the final first SOC threshold.

[0069] Specifically, sub-steps S301a and S301d yield a first SOC threshold that balances theoretical calculation rationality with practical operating condition adaptability. This ensures that the charging capacity reserved in the power battery is sufficient to accommodate the regenerative braking energy generated during long downhill slopes or frequent start-stop operations, while preventing the vehicle from prematurely performing unnecessary active discharge operations due to an excessively low SOC threshold, thus avoiding unnecessary energy waste. Simultaneously, by introducing road gradient and brake pedal opening as correction parameters, the driver's braking needs and the impending braking intensity can be predicted in advance, making the entire pre-adjustment process more targeted and precise. This further enhances the adaptability and reliability of the overall control strategy, better balancing driving safety and range efficiency.

[0070] As an example implementation, the expected amount of electricity to be recovered can be obtained by looking up the charging power limit value in a table, and the SOC percentage of that amount of electricity can be calculated. m At this point, the target SOC threshold is 100- m The braking intensity and the impact of the slope can be comprehensively considered. Based on the brake pedal opening and the slope, the adjustment coefficient can be obtained by further consulting a table. f ac . f ac The value is positively correlated with brake pedal opening and slope. The first SOC threshold is (100- m )× f ac ,and f ac <1.

[0071] In some embodiments, Figure 3 Based on the solution, in order to accurately adjust the SOC value of the power battery, sub-step S303 may further include the following sub-steps S303a-S303c.

[0072] Sub-step S303a: Monitor the SOC value of the power battery.

[0073] Sub-step S303b: In response to the SOC value of the power battery being greater than the first SOC threshold, the range extender is controlled to enter the normal power consumption mode until the SOC value of the power battery is reduced to the first SOC threshold.

[0074] Sub-step S303c: In response to the SOC value of the power battery being less than the first SOC threshold, control the range extender to exit the normal power consumption mode.

[0075] Specifically, sub-steps S303a-S303c dynamically adjust the range extender's operating status based on real-time monitoring results. This ensures that the power battery's SOC is stably controlled at or below the first SOC threshold, reserving sufficient capacity to accommodate regenerative braking energy, while avoiding excessive energy loss due to excessive reduction in the power battery's SOC. When the power battery's SOC is too high, the power consumption process is initiated promptly, completely preventing the problem of insufficient regenerative braking energy and energy waste caused by the power battery being fully utilized. When the SOC falls back to the threshold range, the adjustment is stopped promptly, avoiding unnecessary energy consumption and ensuring that the vehicle's range performance is not affected. Ultimately, a balance is achieved between regenerative braking efficiency and overall vehicle range economy, further improving the accuracy and reliability of the entire vehicle's braking control.

[0076] In some embodiments, Figure 3 Based on the solution, in order to accurately adjust the temperature of the power battery, sub-step S304 may further include the following sub-steps S304a-S304c.

[0077] Sub-step S304a: Monitor the temperature of the power battery cells.

[0078] Sub-step S304b: In response to the power battery cell temperature being lower than a preset first temperature threshold (also known as a low temperature threshold), control the thermal management system to heat the power battery until the power battery cell temperature is within a set temperature range (between the first temperature threshold and the second temperature threshold) that characterizes the appropriate conditions for entering the regenerative braking mode.

[0079] Sub-step S304c: In response to the power battery cell temperature being higher than the preset second temperature threshold (also known as the high temperature threshold), control the thermal management system to dissipate heat from the power battery until the power battery cell temperature is adjusted to the set temperature range used to characterize the appropriate entry into the regenerative braking mode.

[0080] Specifically, through sub-steps S304a-S304c, the temperature of the power battery is precisely controlled in a closed loop. This ensures that the power battery remains within the set temperature range suitable for regenerative braking under different vehicle operating conditions and ambient temperatures. This avoids the problems of insufficient charging capacity of the power battery at low temperatures, which leads to low regenerative braking efficiency and unsatisfactory braking performance. It also solves the hidden dangers of limited charging power and the risk of thermal runaway at high temperatures. This provides a stable temperature guarantee for energy recovery during braking control, effectively improving the recovery and utilization rate of braking energy, thereby improving the vehicle's range performance, extending the cycle life of the power battery, and improving the safety and reliability of the vehicle's braking control process.

[0081] As an exemplary implementation, the first temperature threshold is set to 0℃, and the second temperature threshold is set to 40℃. The set temperature range of 0~40℃ is an adaptive value obtained through extensive operating condition testing and calibration, taking into account the electrochemical characteristics of mainstream power batteries. This range covers the ambient temperature scenarios of most civilian vehicles' daily travel and is compatible with the charging acceptance characteristics of power batteries with different chemical systems, such as lithium iron phosphate and ternary lithium. Within this temperature range, the charging internal resistance of the power battery can be stably maintained at a low level, and the charging acceptance capability can meet the needs of instantaneous high-current energy recovery during braking. This avoids the thermal management system frequently starting and stopping due to an excessively narrow threshold range, thus preventing additional energy consumption of the vehicle, while also preventing the threshold range from being too wide and failing to ensure energy recovery efficiency and avoid battery safety risks. It balances energy recovery efficiency, energy economy, and battery operational safety.

[0082] Figure 4 A flowchart illustrating a recovery torque control scheme provided for at least one embodiment of this disclosure. Figure 2 or Figure 3 Based on the proposed solution, in order to improve the scenario adaptability of the vehicle braking control method, such as... Figure 4 As shown, the recovery torque control scheme in step S40 further includes sub-steps S401-S402.

[0083] Sub-step S401: Obtain the current road gradient and load of the range extender vehicle.

[0084] Sub-step S402: Control the recovery torque of the drive motor based on road slope and load weight.

[0085] Specifically, sub-steps S401-S402 dynamically adjust the torque distribution ratio of regenerative braking based on the current operating conditions of the range-extended vehicle, fully utilizing the energy recovery capability of the generator in the range extender system to share the charging load of the power battery. Road gradient directly reflects the current and upcoming downhill driving conditions and braking intensity, while load directly determines the amount of inertial kinetic energy consumed during braking. Introducing these two parameters for weighted control significantly improves the matching accuracy of the drive motor's regenerative torque. When the vehicle is descending a steep slope and fully loaded, the regenerative torque of the drive motor can be appropriately increased to increase the regenerative energy that the power battery needs to accept, preventing excessive charging power and rapid SOC exceeding the upper limit, thus protecting the power battery's lifespan and operational safety. When the vehicle is on a flat road or unloaded, the regenerative torque of the drive motor can be appropriately reduced to prioritize the use of the power battery to recover braking energy, improving the overall efficiency of energy recovery and utilization. This control method can fully leverage the system advantages of the range-extended architecture, further balancing the safety of the braking process, the reliability of the power battery, and the overall vehicle range economy, thereby improving the scenario adaptability of the vehicle braking control method.

[0086] Figure 5 A flowchart illustrating another vehicle braking control method provided for at least one embodiment of this disclosure. Figures 2-4 Based on any one of the proposed solutions, in order to address the ineffectiveness of the primary pre-control strategy, such as... Figure 5 As shown, the method further includes the following steps S31-S32.

[0087] Step S31: When the power battery reaches the first preferred state, the charging power limit value is compared with the power threshold value again.

[0088] Step S32: When the charging power limit value is still less than the power threshold, a secondary pre-control strategy for the risk of insufficient braking force is triggered. The secondary pre-control strategy is used to control the range extender to continue operating in the normal power consumption mode so that the power battery reaches the second preferred state of preparing to enter the regenerative braking mode.

[0089] It should be noted that the first preferred state refers to the power battery's SOC value being below the first SOC threshold and the power battery's temperature being within the set temperature range used to characterize the suitability for entering the regenerative braking mode.

[0090] Steps S31-S32 can be positioned between steps S30 and S40. Through steps S31-S32, after the execution of the first-level pre-control strategy, if the battery state has been optimized but the charging capacity is still insufficient, there is still a risk of insufficient braking force, which will further trigger the second-level pre-control strategy. This design reflects the hierarchical and progressive nature of the control logic. By further reducing the SOC threshold of the battery, more charging space is created, attempting to restore the battery's charging capacity. This tiered control strategy avoids directly triggering the highest-level alarm or speed limit due to minor battery performance fluctuations, ensuring the stability of the vehicle's powertrain and driving smoothness.

[0091] In some embodiments, Figure 5 Based on the scheme, in order to address the risk of insufficient braking force due to the inadequacy of the primary pre-control strategy, the secondary pre-control strategy in step S32 may further include the following sub-steps S321-S322.

[0092] Sub-step S321: Determine the second SOC threshold based on the first SOC threshold.

[0093] Sub-step S322: Control the range extender to continue operating in the normal power consumption mode so that the SOC value of the power battery is adjusted to below the second SOC threshold through the power consumption of the range extender.

[0094] The first SOC threshold is higher than the second SOC threshold. Through sub-steps S321-S322, the secondary pre-control strategy sets a second SOC threshold lower than the first SOC threshold, further increasing the charging margin of the power battery. This indicates that when the system confirms that the primary pre-control strategy is insufficient to cope with the current operating conditions, it will take more aggressive discharge measures to ensure safety. This phased SOC reduction strategy avoids unnecessary over-discharge, saves fuel, and provides stronger protection capabilities when necessary, achieving a balance between energy efficiency and safety.

[0095] In the above scheme, the second SOC threshold can be set empirically. When the SOC value of the power battery is at the second SOC threshold, its charging power should theoretically not be limited. If the charging power is still limited, it indicates that the power battery may be faulty. At this time, continuing to discharge is only intended to try to remove the limitation, and the specific value of the discharge is irrelevant.

[0096] Figure 6 A flowchart illustrating yet another vehicle braking control method provided for at least one embodiment of this disclosure. Figure 5 Based on the plan, in order to address the ineffectiveness of the secondary pre-control strategy, such as Figure 6 As shown, the method further includes the following steps S33-S34.

[0097] Step S33: When the state of the power battery reaches the second preferred state, the charging power limit value is compared with the power threshold value again.

[0098] Step S34: When the charging power limit value is still less than the power threshold, the three-level pre-control strategy is triggered. The three-level pre-control strategy is used to control the range extender to enter an emergency power consumption mode that is different from the normal power consumption mode, so as to absorb the braking recovery energy, issue an alarm to indicate the braking fault, and limit the speed of the vehicle.

[0099] It should be noted that the second preferred state refers to the power battery's SOC value being below the second SOC threshold and the power battery's temperature being within the set temperature range used to characterize the suitability for entering the regenerative braking mode.

[0100] Steps S33-S34 can be placed after step S32. Through steps S30-S34, a three-level pre-control strategy is established as a final safety fallback mechanism. When the power battery state still cannot meet the charging demand after adjustments by the two-level pre-control strategy, the system forces the range extender into an emergency power consumption mode to physically absorb braking energy, simultaneously triggering a braking fault alarm and limiting the vehicle speed. This mechanism completely solves the fatal safety hazard of no braking force in extreme situations, such as severe battery degradation or failure, by actively limiting vehicle speed to reduce the demand for braking force, thereby ensuring the absolute safety of the driver and the vehicle.

[0101] In the above scheme, the emergency power consumption mode is used to actively create an energy absorption channel when the charging limitation of the power battery cannot be lifted, providing a destination for the energy recovered during impending braking. The emergency power consumption mode differs from the conventional power consumption mode in that it has greater control intensity and higher priority. For example, the emergency power consumption mode can be set to operate at maximum power consumption to achieve high-intensity power consumption. In this case, safety takes a backseat to economy.

[0102] In some embodiments, Figure 6 Based on the scheme, in order to ensure driving safety under braking failure, the three-level pre-control strategy in step S34 can further include the following sub-steps S341-S343.

[0103] Sub-step S341: Control the range extender to enter the emergency power consumption mode, wherein, in the emergency power consumption mode, the engine enters the in-cylinder braking state, and the generator reverse-drives the engine to absorb braking energy recovery.

[0104] Sub-step S342: Issue an alarm to characterize a braking malfunction.

[0105] Sub-step S343: Based on the vehicle's current load, classify the vehicle's speed limit, where different load ranges correspond to different target speed limit values.

[0106] It should be noted that in sub-step S341, the generator uses speed control, the engine cylinder brakes, and the generator reverse-drives the engine. At this time, the generator will act as a power-consuming device to achieve emergency power consumption.

[0107] The three-level pre-control strategy specifically defines the execution methods for emergency power consumption by the range extender, including engine in-cylinder braking and generator reverse drag. This is a highly efficient and reliable physical energy absorption method that can directly consume the braking energy generated by the motor without relying on the power battery. Meanwhile, the load-based graded speed limiting strategy can set targeted safe speeds for fully loaded, half-loaded, and unloaded vehicles according to their actual load conditions. Compared to a single speed limit, this better balances transportation efficiency and safety requirements under different operating conditions.

[0108] In some embodiments, the speed limit levels in sub-step S343 include at least a full-load speed limit, a half-load speed limit, and an unloaded speed limit. Different speed limit levels correspond to different target speed limit values. Unloaded is identified by a load weight less than a first preset weight; full-load is identified by a load weight greater than a second preset weight; and half-load is identified by a load weight greater than the first preset weight but less than the second preset weight. Unloaded corresponds to an unloaded speed limit, half-load corresponds to a half-load speed limit, and full-load corresponds to a full-load speed limit.

[0109] Figure 7 A flowchart illustrating yet another vehicle braking control method provided for at least one embodiment of this disclosure. Figures 2-6 Based on any given scheme, in order to accurately obtain the power threshold that matches the current operating conditions, such as Figure 7 As shown, the method may further include the following steps S01-S02.

[0110] Step S01: Obtain the vehicle's current speed and load.

[0111] Step S02: Determine the power threshold that matches the current operating conditions based on vehicle speed and load.

[0112] Specifically, the power threshold increases with increasing vehicle speed and load. Steps S01-S02 dynamically determine the power threshold based on real-time vehicle speed and load, making the prediction of insufficient braking force risk more scientific and accurate. Since higher vehicle speed and heavier load result in greater vehicle kinetic energy and a higher demand for regenerative braking, adjusting the power threshold accordingly ensures sufficient energy absorption margin for the power battery under high-risk conditions. This load-based adaptive threshold setting method effectively avoids the failure of fixed thresholds in dangerous scenarios such as heavy-load downhill driving, significantly improving the robustness of the vehicle braking control method.

[0113] In some embodiments, Figure 7Based on the scheme, in order to quickly obtain the power threshold that matches the current operating conditions, step S02 further includes the following sub-steps S021-S022.

[0114] Sub-step S021: In response to the vehicle speed being less than the first set speed and the load being less than the first set weight, output the first set power as the power threshold.

[0115] Sub-step S022: In response to the vehicle speed being higher than the second set speed and the load being greater than the second set weight, output the second set power as the power threshold.

[0116] In this system, the first set speed is lower than the second set speed, the first set weight is lower than the second set weight, and the first set power is lower than the second set power. Sub-step S021 allows the system to match a lower power threshold when the vehicle is in a low-speed, light-load condition, enabling the system to identify the risk that the power battery cannot accommodate the regenerative braking energy earlier and trigger the corresponding pre-control strategy in a timely manner to ensure braking safety. Sub-step S022 allows the system to match a higher power threshold when the vehicle is in a high-speed, heavy-load condition, which not only meets the actual requirements for regenerative braking capacity under this condition but also avoids unnecessary strategy triggering that interferes with the normal driving of the vehicle. This ensures the accuracy and rationality of the braking control logic under different driving scenarios, further improving the overall safety of vehicle braking.

[0117] In the above scheme, the power threshold can be confirmed by looking up a table based on vehicle speed and load. This disclosure does not limit the boundary values ​​of the vehicle speed at the first set speed or the second set speed, or the boundary values ​​of the load at the first set weight or the second set weight; these can be set according to actual needs.

[0118] Figure 8 A flowchart illustrating yet another vehicle braking control method provided for at least one embodiment of this disclosure. Figures 2-7 Based on any one of the options, such as Figure 8 As shown, the method further includes the following steps S50-S60.

[0119] Step S50: In regenerative braking mode, continuously monitor the SOC value of the power battery and the temperature of multiple components in the power system of the range-extended vehicle.

[0120] Step S60: When any of the SOC value of the power battery or the temperature of multiple components in the power system of the range-extended vehicle changes, a control command is generated to compare the charging power limit value with a power threshold used to predict the risk of insufficient braking force, so as to prevent the risk of insufficient braking force in the vehicle during regenerative braking mode.

[0121] Steps S50-S60 can be placed after step S40. In step S50, the temperatures of multiple components include at least the temperature of the power battery and the temperature of the drive motor. Through steps S50-S60, key temperature parameters of the power battery and power system are continuously monitored in regenerative braking mode, and risk prediction and processing logic are triggered in real time based on changes in these parameters. This closed-loop feedback mechanism can cope with transient changes during braking, preventing sudden interruption of energy recovery due to sudden changes in the power battery state, such as a sudden rise in temperature leading to power limitation. This ensures the continuity and stability of braking force and effectively eliminates safety hazards during braking.

[0122] Figure 9 A flowchart illustrating an example of a vehicle braking control method provided in at least one embodiment of this disclosure. (See flowchart for example.) Figure 9 As shown, examples of this method include: 1) When the vehicle has a speed, determine whether the charging power limit of the power battery is less than the preset power threshold. The power threshold is obtained by looking up a table based on the vehicle speed and load. If yes, proceed to 2); if no, proceed to 5). 2) The VCU controls the range extender to consume power until the SOC is less than the first SOC threshold. When the temperature of the power battery cell is less than 0°C or greater than 40°C, the VCU controls the TMS to keep the temperature of the power battery cell within 0~40°C, and then executes 3). The first SOC threshold is calculated based on the power threshold in 1) to calculate the amount of electricity to be recovered and then to calculate the value that the SOC needs to be reduced to. 3) When the SOC value is less than the first SOC threshold and the temperature of the power battery cell is within 0℃~40℃, it is determined again whether the power battery charging power limit value <1) is met. If yes, the VCU continues to control the range extender to consume power until the SOC value is less than the second SOC threshold. The second SOC threshold is equal to the first SOC threshold minus 10 (unit: %). If no, proceed to step 5). 4) When the SOC value is less than the second SOC threshold, it is checked again whether the power battery charging power limit value is less than the power threshold in 1). If so, the VCU controls the range extender to consume power urgently to absorb the energy recovered by braking in order to ensure the vehicle's braking force. At the same time, a braking fault is reported and the vehicle speed is limited. If not, proceed to 5). 5) When the charging power limit is greater than or equal to the preset power threshold and the driver has braking needs, the VCU controls the motor recovery torque according to the road gradient and load weight. During this process, the SOC value and the temperature of various components in the drive system (including motor temperature and power battery temperature) change, then return to execution 1).

[0123] The system employs a three-step, step-by-step approach to reduce the State of Charge (SOC) value, gradually distinguishing between insufficient charging power caused by a normal high SOC and charging power limitation due to a battery malfunction. This ensures sufficient space to receive regenerative braking energy and adequate braking force while preventing the range extender from wasting power, balancing braking safety and vehicle economy. When the range extender's emergency power consumption process is triggered, it indicates a battery malfunction that prevents it from meeting normal charging needs. Timely fault reporting and speed limiting alert the driver to take appropriate action and avoid driving hazards. By calculating the motor's regenerative torque based on road gradient and load weight, the system can adapt to different braking force requirements in various driving scenarios: increasing regenerative torque on downhill sections to ensure sufficient braking force, and matching the vehicle's inertia to achieve the required braking deceleration under heavy loads, effectively improving braking smoothness and driving safety.

[0124] Figure 10 This is a structural block diagram of a vehicle braking control system provided in at least one embodiment of the present disclosure. Figure 10 As shown, the vehicle braking control system 100 integrates an acquisition unit 101, a preprocessing unit 102, a risk pre-control unit 103, and a braking control unit 104.

[0125] The acquisition unit 101 is configured to acquire the current charging power limit value of the power battery during vehicle operation.

[0126] The preprocessing unit 102 is configured to compare the charging power limit value with a power threshold used to predict the risk of insufficient braking force.

[0127] The risk pre-control unit 103 is configured to trigger a first-level pre-control strategy for the risk of insufficient braking force when the charging power limit value is less than the power threshold. The first-level pre-control strategy is used to control the range extender to enter the normal power consumption mode and control the thermal management system to adjust the temperature of the power battery so that the power battery reaches the first preferred state for entering the regenerative braking mode.

[0128] The brake control unit 104 is configured to dynamically adjust the regenerative torque of the drive motor based on the vehicle's operating parameters when braking is required, so as to perform safe braking on the vehicle.

[0129] The specific execution operations of each unit in the above system embodiments have been described in detail in the embodiments related to the method, and will not be elaborated here.

[0130] In some embodiments, Figure 10 Based on the scheme, the acquisition unit 101 can be implemented by corresponding sensors or receiving modules, and the preprocessing unit 102, risk pre-control unit 103 and braking control unit 104 can be implemented by controllers with corresponding programs.

[0131] In some embodiments, Figure 10 Based on the scheme, the risk pre-control unit 103 is also configured to compare the charging power limit value with the power threshold again when the state of the power battery reaches the first preferred state, and to trigger a secondary pre-control strategy for the risk of insufficient braking force when the charging power limit value is still less than the power threshold. The secondary pre-control strategy is used to control the range extender to continue to operate in the normal power consumption mode so that the power battery reaches the second preferred state of preparing to enter the regenerative braking mode.

[0132] In some embodiments, Figure 10 Based on the scheme, the risk pre-control unit 103 is also configured to compare the charging power limit value with the power threshold again when the state of the power battery reaches the second preferred state, and to trigger a three-level pre-control strategy when the charging power limit value is still less than the power threshold. The three-level pre-control strategy is used to control the range extender to enter an emergency power consumption mode that is different from the normal power consumption mode in order to absorb braking recovery energy, issue an alarm to indicate braking failure, and limit the speed of the vehicle.

[0133] In some embodiments, Figure 10 Based on the solution, the brake control unit 104 is also configured to continuously monitor the SOC value of the power battery, the temperature of the power battery, and the temperature of the drive motor in the regenerative braking mode, and to generate control commands to execute a comparison between a charging power limit value and a power threshold used to predict the risk of insufficient braking force when any of the SOC value of the power battery, the temperature of the power battery, and the temperature of the drive motor changes, so as to prevent the risk of insufficient braking force in the vehicle in the regenerative braking mode.

[0134] In some embodiments, Figure 10 Based on the solution, the vehicle braking control system 100 also integrates a threshold control unit, which is configured to acquire the vehicle's current speed and load, and determine a power threshold that matches the current operating conditions based on the speed and load.

[0135] This disclosure also provides a storage medium storing a program or instructions that, when executed by a processor, implement the steps of the method embodiments described above.

[0136] This disclosure also provides a program product, such as... Figure 11 As shown, the program product includes one or more processors 201 and memory 202. Figure 11 Take a processor 201 as an example.

[0137] The controller may also include an input device 203 and an output device 204.

[0138] The processor 201, memory 202, input device 203, and output device 204 can be connected via a bus or other means. Figure 11 Taking the example of a connection between China and Israel via a bus.

[0139] Processor 201 can be a central processing unit (CPU), or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or combinations of the above types of chips. The general-purpose processor can be a controller or any conventional processor.

[0140] The memory 202, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the methods in the embodiments of this disclosure. The processor 201 executes various functional applications and data processing of the controller by running the non-transitory software programs, instructions, and modules stored in the memory 202, thereby implementing the steps of the above-described method embodiments.

[0141] The memory 202 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created by the use of the processing device operated by the server. Furthermore, the memory 202 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 202 may optionally include memory remotely located relative to the processor 201, and these remote memories can be connected to a network connection device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0142] Input device 203 can receive input numeric or character information, and generate key signal inputs related to user settings and function control of the server's processing device. Output device 204 may include display devices such as a display screen.

[0143] One or more modules are stored in memory 202, and when executed by one or more processors 201, they perform actions such as... Figure 2-9Any of the methods shown.

[0144] Those skilled in the art will understand that all or part of the processes in the above method embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), random access memory (RAM), flash memory (FM), hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0145] Although embodiments of the present disclosure have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present disclosure, and all such modifications and variations fall within the scope defined by the appended claims.

[0146] Although embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A vehicle braking control method, applied to a range-extended vehicle having a range extender, a power battery, a drive motor, and a thermal management system, characterized in that, include: During vehicle operation, obtain the current charging power limit value of the power battery; The charging power limit value is compared with the power threshold used to predict the risk of insufficient braking force; When the charging power limit is less than the power threshold, a primary pre-control strategy for the risk of insufficient braking force is triggered. This primary pre-control strategy controls the range extender to enter a normal power consumption mode and controls the thermal management system to regulate the temperature of the power battery, so that the power battery reaches a first preferred state for entering the regenerative braking mode. When the vehicle requires braking, the recovery torque of the drive motor is dynamically adjusted based on the vehicle's operating parameters, so that the vehicle can perform braking energy recovery that is adapted to the current operating conditions.

2. The method according to claim 1, characterized in that, Also includes: When the power battery reaches the first preferred state, the charging power limit value is compared with the power threshold value again. as well as, When the charging power limit is still less than the power threshold, a secondary pre-control strategy for the risk of insufficient braking force is triggered. The secondary pre-control strategy is used to control the range extender to continue operating in the normal power consumption mode so that the power battery reaches the second preferred state of preparing to enter the regenerative braking mode.

3. The method according to claim 2, characterized in that, Also includes: When the power battery reaches the second preferred state, the charging power limit value is compared with the power threshold value again; as well as, When the charging power limit value is still less than the power threshold, a three-level pre-control strategy is triggered. The three-level pre-control strategy is used to control the range extender to enter an emergency power consumption mode that is different from the normal power consumption mode, so as to absorb braking recovery energy, issue an alarm to indicate braking failure, and limit the speed of the vehicle.

4. The method according to any one of claims 1-3, characterized in that, Also includes: Obtain the current speed and load of the vehicle; and, The power threshold matching the current operating conditions is determined based on the vehicle speed and the load. Specifically, as the vehicle speed and load increase, the power threshold value increases accordingly.

5. The method according to any one of claims 1-3, characterized in that, Also includes: In regenerative braking mode, the SOC value of the power battery and the temperature of multiple components in the power system of the range-extended vehicle are continuously monitored. When any of the SOC value of the power battery or the temperature of multiple components in the power system of the range-extended vehicle changes, a control command is generated to compare the charging power limit value with a power threshold used to predict the risk of insufficient braking force, so as to prevent the risk of insufficient braking force in the vehicle during regenerative braking mode.

6. The method according to any one of claims 1-3, characterized in that, The primary pre-control strategy includes: The first SOC threshold is determined based on the power threshold; Obtain the SOC value and temperature of the power battery; In response to the SOC value of the power battery being greater than the first SOC threshold, the range extender is controlled to enter a normal power consumption mode, so as to adjust the SOC value of the power battery to below the first SOC threshold through the power consumption of the range extender; and, In response to the temperature of the power battery exceeding the set temperature range used to characterize suitability for entering the regenerative braking mode, the thermal management system is controlled to adjust the temperature of the power battery so that the temperature of the power battery is regulated to the set temperature range.

7. The method according to claim 2, characterized in that, The secondary pre-control strategy includes: A second SOC threshold is determined based on the first SOC threshold; and... The range extender is controlled to continue operating in the normal power consumption mode so that the SOC value of the power battery is adjusted to below the second SOC threshold through the power consumption of the range extender. Wherein, the first SOC threshold is greater than the second SOC threshold.

8. The method according to claim 3, characterized in that, The range extender includes an engine and a generator, and the three-level pre-control strategy includes: The range extender is controlled to enter an emergency power consumption mode, wherein, in the emergency power consumption mode, the engine enters an in-cylinder braking state, and the generator reverse-drives the engine to absorb braking energy. Issue an alarm to indicate a braking malfunction; and, The vehicle's speed is limited in stages based on its current load, with different load ranges corresponding to different target speed limits.

9. A vehicle braking control system, applied to a range-extended vehicle having a range extender, a power battery, a drive motor, and a thermal management system, characterized in that, include: The acquisition unit is configured to acquire the current charging power limit value of the power battery during vehicle operation; The preprocessing unit is configured to compare the charging power limit value with a power threshold used to predict the risk of insufficient braking force; A risk pre-control unit is configured to trigger a primary pre-control strategy for insufficient braking force risk when the charging power limit value is less than the power threshold. This primary pre-control strategy controls the range extender to enter a normal power consumption mode and controls the thermal management system to adjust the temperature of the power battery, so that the power battery reaches a first preferred state for entering regenerative braking mode. The braking control unit is configured to dynamically adjust the regenerative torque of the drive motor based on the vehicle's operating parameters when braking is required, so as to perform safe braking on the vehicle.

10. A storage medium, characterized in that, The storage medium stores a program or instructions, wherein the program or instructions, when executed by a processor, implement the steps of the method as described in any one of claims 1 to 8.

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