Braking energy recovery control method for pure electric vehicle based on driving style

Abstract

The invention belongs to the technical field of electric vehicle braking energy recovery, and particularly relates to a pure electric vehicle braking energy recovery control method based on a driving style, which comprises the following steps: S1, working condition identification: detecting the operation state of a driver through a sensor, and distinguishing an accelerator working condition, a sliding working condition and a braking working condition; s2, gear setting, wherein multiple levels of basic recovery gears capable of being manually adjusted are provided, and each gear corresponds to a preset basic recovery strength range; s3, sliding working condition control is conducted, specifically, dynamic adjustment is conducted in combination with scene parameters and vehicle state parameters within the basic recovery strength range corresponding to the basic recovery gear; and S4, brake working condition control, wherein different brake types are distinguished according to brake operation characteristics. According to the method, the core control right of a driver for setting the recovery strength through multi-stage manual gears is reserved, dynamic fine adjustment is conducted in combination with scenes and vehicle states, driving habits and complex road condition requirements are balanced, and differential strategies are executed by distinguishing brake types.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric vehicle braking energy recovery, and in particular relates to a driving style-based pure electric vehicle braking energy recovery control method. Background Art

[0002] With the rapid development of the new energy vehicle industry, the range and energy efficiency of pure electric vehicles have become core concerns for users. As a key means of improving range, the performance optimization of brake energy recovery technology has always been a hot topic in the industry. The core principle of brake energy recovery is that when the vehicle decelerates or brakes, the drive motor switches to generator mode, converting the vehicle's kinetic energy (or gravitational potential energy) into electrical energy and storing it in the power battery, thereby reducing energy waste and extending range.

[0003] At present, the braking energy recovery control strategies of pure electric vehicles are mainly divided into two categories: fully automatic control strategy and manual adjustment control strategy, but both strategies have obvious technical limitations;

[0004] Fully automatic control strategies use sensors to identify driving intent (such as accelerator pedal position, brake pedal pressure, and vehicle speed change rate), and the system automatically adjusts the energy recovery intensity. The core problem with this strategy is the lack of driver control. The recovery intensity is completely determined by the system, and the driver cannot intervene based on personal driving habits (such as their tolerance for "drag") or scenario requirements (such as the need for smooth gliding in congested roads). This can easily lead to a fragmented driving experience. Existing fully automatic strategies often rely on a single parameter (such as vehicle speed or SOC) to adjust the recovery intensity, making it difficult to cope with complex road conditions.

[0005] To address driver control issues, some models offer manual gear adjustment, allowing drivers to select the recuperation intensity based on their preferences. However, this strategy has the disadvantage of fixed recuperation intensity for each manual gear (e.g., 1st gear corresponds to weak recuperation, 2nd gear corresponds to strong recuperation), which cannot be dynamically adjusted based on road conditions or vehicle status. Furthermore, it fails to consider vehicle status and safety margins: manual adjustment relies solely on the driver's subjective judgment, without considering parameters such as battery status and motor temperature, posing the risk of component damage or safety issues.

[0006] Moreover, whether it is a fully automatic or manual adjustment strategy, existing technologies often treat braking conditions as a single scenario, using a fixed logic of "recovery intensity increases linearly with pedal travel" without distinguishing between "light braking" (such as deceleration and coasting) and "hard braking" (such as emergency avoidance).

[0007] Driving habits vary significantly between drivers (e.g., aggressive drivers prefer strong power response, while more conservative drivers prioritize smoothness). However, existing recuperation strategies are not optimized for these driving styles. For example, aggressive drivers often experience increased operational burden due to frequent manual adjustments, while more conservative drivers may miss energy recuperation opportunities because the system does not automatically increase recuperation intensity.

[0008] In summary, existing technologies struggle to balance driver control, scenario adaptability, vehicle safety, and energy recovery efficiency. Therefore, a new brake energy recovery control method is urgently needed that retains the driver's core control over recovery intensity while enabling intelligent adjustment through dynamic adaptation to scenarios and conditions. This method also optimizes refined control of braking conditions, ultimately improving the range, driving experience, and safety of pure electric vehicles. Summary of the Invention

[0009] The purpose of the present invention is to provide a pure electric vehicle brake energy recovery control method based on driving style, which not only retains the driver's core control right to set the recovery intensity through multi-level manual gear, but also combines dynamic fine-tuning with the scene and vehicle status, balances driving habits and complex road conditions, and implements differentiated strategies by distinguishing brake types, taking into account energy recovery and braking safety, adapting to driving style to reduce operating burden, and protecting batteries and motors at the same time.

[0010] The technical solutions adopted by the present invention are as follows:

[0011] A method for controlling braking energy recovery of a pure electric vehicle based on driving style comprises the following steps:

[0012] S1: Operating condition identification: The sensor detects the driver's operating status and distinguishes between throttle, coasting and braking conditions;

[0013] S2: Gear Setting: Provides multiple manually adjustable basic recycling gears, each gear corresponding to a preset basic recycling intensity range;

[0014] S3: Coasting Control: Within the basic recuperation intensity range corresponding to the basic recuperation gear, dynamic adjustments are made based on scenario parameters and vehicle status parameters to obtain and execute the actual recuperation intensity.

[0015] S4: Braking condition control: Different braking types are distinguished according to the braking operation characteristics, and corresponding energy recovery and mechanical braking coordination strategies are implemented for different braking types.

[0016] In S1, when it is detected that the accelerator pedal opening is greater than a preset threshold, it is determined to be a throttle operating condition and energy recovery is not started;

[0017] When the accelerator pedal is fully released and no brake operation is detected, it is determined to be in coasting condition;

[0018] When a brake operation is detected, it is determined to be a brake condition.

[0019] In S2, the basic recovery gear that can be manually adjusted in multiple stages is 5, and each gear corresponds to a different recovery torque range.

[0020] In said S3, the dynamic adjustment in the coasting condition control includes scene dimension adjustment and state dimension adjustment;

[0021] The scene dimension adjustment specifically includes:

[0022] Adjust the recovery intensity based on the distance to the vehicle ahead and the vehicle's speed;

[0023] Adjust the recovery intensity based on the road slope;

[0024] Adjust the recovery intensity and recovery start timing based on vehicle speed detection;

[0025] The state dimension adjustment specifically includes:

[0026] Analyze battery state of charge to adjust recycling intensity;

[0027] Adjust the adjustment amplitude of the scene dimension based on driving style characteristics.

[0028] In S3, under the coasting control condition, the actual regeneration torque is calculated by taking the reference torque of the current basic regeneration gear as a basis, combining the scene adjustment coefficient and the state adjustment coefficient, and limiting the calculation result to the basic regeneration intensity range corresponding to the current basic regeneration gear;

[0029] Specifically:

[0030] T slide =T base ×(1+K′ scene +K state )

[0031] Among them, T slide is the actual recovery torque, T base is the median value of the basic torque of the current gear, K′ scene is the adjusted scenario comprehensive fine-tuning coefficient, which is obtained by superimposing the sub-coefficients of each scenario and correcting them according to the driving style characteristics:

[0032] K′ scene =(K follow +K slope +K lowv )×α

[0033] Among them, K follow is the fine-tuning coefficient for the following vehicle scenario, K slopeis the fine-tuning coefficient for downhill scenes, K lowv is the low-speed scene fine-tuning coefficient, α is the driving style correction coefficient;

[0034] K state is the comprehensive fine-tuning coefficient of the state.

[0035] In S4, the braking operation characteristics include at least one of the following: a brake pedal depression speed, a brake pedal travel depth, and the braking type includes normal braking and emergency braking;

[0036] For the ordinary brake, a control strategy with energy recovery priority is adopted. The recovery intensity is based on the preset highest gear recovery intensity and is dynamically adjusted in combination with the vehicle speed. Mechanical braking supplements the insufficient braking force.

[0037] For the emergency brake, a safety-first control strategy is adopted, which first starts the over-limit recovery and triggers the mechanical brake to respond quickly. The recovery intensity dynamically decays as the vehicle speed decreases, and at low speeds, it relies entirely on mechanical braking.

[0038] The calculation formula for the instantaneous power P recovered during braking is:

[0039]

[0040] Among them, T recycle is the actual recovery torque, n is the motor speed;

[0041] Moreover, the attenuation formula of the actual recovery torque speed is:

[0042]

[0043] T recycle =0(V≤20km / h)

[0044] Among them, T max_emerg is the initial maximum recovery torque of the brake, V0 is the reference vehicle speed, and V is the real-time vehicle speed.

[0045] It also includes a protection mechanism that reduces the recovery intensity or turns off energy recovery when it detects that the status of vehicle components exceeds a preset safety threshold.

[0046] The sensors include an accelerator pedal sensor, a brake pedal sensor, a distance detection sensor, a slope sensor, a vehicle speed sensor, a battery status monitoring module, and a driving behavior recording module.

[0047] The technical effects achieved by the present invention are:

[0048] The present invention not only retains the driver's core control over the recovery intensity through multi-level manual gear settings, but also dynamically fine-tunes the scene and vehicle status, balances driving habits and complex road conditions, and implements differentiated strategies by distinguishing brake types, taking into account both energy recovery and braking safety, adapting to driving style to reduce operational burden, while protecting the battery and motor, ultimately improving battery life and comfort, and achieving coordinated optimization of control, adaptability, safety and efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 is a general flow chart of the overall method of the present invention;

[0050] Figure 2 It is a flow chart for judging the throttle working condition and the brake working condition in the present invention. DETAILED DESCRIPTION

[0051] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is described in detail below with reference to the following examples. It should be understood that the following text is only used to describe one or more specific embodiments of the present invention and does not strictly limit the scope of protection of the present invention.

[0052] like Figure 1-Figure 2 As shown, a driving style-based braking energy recovery control method for a pure electric vehicle includes the following steps:

[0053] S1: Operating Condition Identification: Sensors detect the driver's operating status and distinguish between throttle, coasting, and braking conditions. Energy recovery can be manually adjusted from 1 to 5 levels, integrated within easy reach of the driver. The driver can set the recovery level, with level 1 providing the least energy recovery and level 5 providing the most. The energy recovery module can also automatically adjust the recovery level, as described above.

[0054] When the accelerator pedal opening is detected to be greater than a preset threshold, it is determined to be in throttle operation mode and energy recovery is not activated;

[0055] When the accelerator pedal is fully released and no brake operation is detected, it is determined to be in coasting condition;

[0056] When a braking operation is detected, it is determined to be a braking condition;

[0057] The sensors include an accelerator pedal sensor, a brake pedal sensor, a distance detection sensor, a slope sensor, a vehicle speed sensor, a battery status monitoring module, and a driving behavior recording module;

[0058] Furthermore, the accelerator pedal sensor may be a Hall-type non-contact sensor with a measurement range of 0-100% opening, a sampling frequency of 100 Hz, a measurement accuracy of ±1% FS (full scale), and an output signal of 0-5V voltage, corresponding to a pedal opening of 0-100%, where "fully released" is defined as an opening of ≤1%, and "pressed" is defined as an opening of >5%;

[0059] The brake pedal sensor integrates a travel sensor and a speed sensor, with a travel measurement range of 0-100mm, a speed measurement range of 0-50cm / s, a sampling frequency of 200Hz, and an accuracy of ±2%FS. It is used to distinguish between "normal braking" and "emergency braking";

[0060] A millimeter-wave radar has also been added, using a 77GHz forward-facing radar with a detection range of 0.5-150m. It is used to detect the distance to the vehicle in front and supports following vehicle scene recognition. The millimeter-wave radar can be replaced by a 360-degree monitor around the vehicle.

[0061] Use gyroscopes and slope sensors to detect road slope and distinguish between flat roads and downhill scenarios.

[0062] A wheel speed sensor has also been added, which uses a Hall-type wheel speed sensor to calculate the current vehicle speed and slip rate during braking.

[0063] The battery status monitoring module supports real-time acquisition of battery state of charge, cell voltage, temperature, and other parameters at a sampling frequency of 10Hz. It is used to determine whether the battery is fully charged or low on power.

[0064] The driver behavior recorder is integrated into the vehicle controller and records the number and frequency of recovery gear changes made by the driver over the past 100 km, which can be used to identify "frequent fine-tuning" or "fixed preference" driving styles.

[0065] The decision-making layer is responsible for working condition identification, gear analysis, and scene and state adaptation calculation. The core hardware consists of the main controller and auxiliary decision-making chip;

[0066] The execution layer is responsible for receiving instructions from the decision layer, executing the coordinated control of energy recovery and mechanical braking, and providing status feedback:

[0067] The main controller uses the signals collected by the perception layer to determine the current driving conditions in real time. The specific logic is as follows:

[0068] When the accelerator pedal opening is greater than 5%, it is determined as "driver-initiated acceleration". At this time, the main controller sends a command such as "disable energy recovery" to the motor controller, and the motor only outputs driving torque. This is the throttle working condition;

[0069] When the accelerator pedal is fully released and the brake is not pressed, it is judged as "coasting" and the energy recovery control based on the customized gear is activated. This is the coasting condition;

[0070] When the brake pedal opening is greater than 0%, that is, the brake is pressed, it is judged as "braking", and the enhanced energy recovery and mechanical brake coordinated control are activated. This is the braking condition;

[0071] To avoid frequent switching of operating modes (such as jitter when releasing the accelerator), a 50ms hysteresis loop is set. To switch from the throttle mode to the coasting mode, the throttle opening must be 0% for 50ms, and the brake opening must be > 0% for 20ms.

[0072] S2: Gear Setting: Provides multiple manually adjustable basic recycling gears, each gear corresponding to a preset basic recycling intensity range;

[0073] The multi-level manually adjustable basic recovery gear has 5 levels, each corresponding to a different recovery torque range;

[0074] The driver manually sets the regeneration intensity for gears 1-5. The corresponding basic regeneration torque range and deceleration for each gear are shown in Table 1 below:

[0075]

[0076] Moreover, the vehicle deceleration corresponding to the recovery torque (unit: g, 1g = 9.81m / s 2 ) is derived as follows:

[0077]

[0078] Among them, T recycle is the actual recovery torque, i is the transmission system reduction ratio, η is the transmission efficiency, m is the vehicle curb mass, r is the wheel rolling radius, and g is the acceleration due to gravity.

[0079] S3: Coasting Control: Within the basic regeneration intensity range corresponding to the basic regeneration gear, the system dynamically adjusts the regeneration intensity based on scenario parameters and vehicle status parameters to determine and execute the actual regeneration intensity. In coasting conditions, the system dynamically fine-tunes the regeneration torque based on the gear set by the driver, taking into account the scenario and vehicle status.

[0080] Dynamic adjustments in taxiing control include scene dimension adjustments and state dimension adjustments;

[0081] Scene dimension adjustments specifically include:

[0082] Adjust the recovery intensity based on the distance to the vehicle ahead and the vehicle's speed;

[0083] Adjust the recovery intensity based on the road slope;

[0084] Adjust the recovery intensity and recovery start timing based on vehicle speed detection;

[0085] Status dimension adjustments specifically include:

[0086] Analyze battery state of charge to adjust recycling intensity;

[0087] Adjust the adjustment amplitude of the scenario dimension based on driving style characteristics;

[0088] The main controller reads the current gear position, obtains the corresponding base regenerative torque range from Table 1, sets the initial regenerative torque to the midpoint of the range, and calculates the scenario fine-tuning coefficient based on environmental parameters collected by the millimeter-wave radar, gyroscope, and wheel speed sensor to correct the base torque.

[0089] When the distance to the vehicle ahead is less than 50m and the vehicle's speed is greater than 30km / h, it is considered "close following" and the regeneration force is reduced to prevent a possible rear-end collision due to excessive speed. In this case, the regeneration torque is increased by 10%, and fine-tuning of the following scenario is performed.

[0090] When the distance to the preceding vehicle is greater than or equal to 50m or the vehicle's speed is less than 30km / h, the following fine-tuning will not be performed;

[0091] When the road slope is greater than 5° and lasts for more than 3 seconds, it is considered "effective downhill" and the recovery intensity needs to be increased to utilize gravity potential energy. At this time, the recovery torque increases by 15%;

[0092] When the road slope is less than or equal to 5° or the road slope is greater than 5° and the duration does not exceed 3s, downhill fine-tuning will not be performed;

[0093] When the vehicle speed is less than 20 km / h, it is considered "low speed driving" and the regeneration intensity needs to be reduced and the start is delayed to reduce the sense of frustration. At this time, the regeneration torque is reduced by 5%, and the regeneration start delay is 0.5s. The regeneration start delay is the interval from releasing the accelerator to the start of regeneration.

[0094] When the vehicle speed is greater than or equal to 20km / h, low-speed fine-tuning is not performed;

[0095] Based on the vehicle status parameters collected by the BMS and driving behavior recorder, the state fine-tuning coefficient is calculated to further correct the regenerative torque:

[0096] When the battery SOC is greater than 90%, the full charge protection is triggered and the recycling intensity needs to be reduced to avoid overcharging the battery;

[0097] When the battery SOC is less than 20%, the battery is depleted and the energy is replenished. The recovery intensity needs to be increased to prioritize energy replenishment.

[0098] When 20% ≤ battery SOC ≤ 90%, it is a normal state and battery SOC fine-tuning is not performed;

[0099] Driving style adaptation fine-tuning is that the main controller analyzes the gear shift records of the past 100km,

[0100] If the average number of gear changes per day is greater than 5, the vehicle is considered to be "frequently fine-tuned" and the scene fine-tuning range is halved to respect the driver's manual adjustment habits.

[0101] If the gear is not switched for 3 consecutive days, it is determined to be a "fixed preference type" and the scene fine-tuning range remains unchanged;

[0102] When multiple scenario conditions are met simultaneously, the scenario comprehensive fine-tuning coefficient is the algebraic sum of the coefficients of each scenario;

[0103] In coasting mode, the actual regeneration torque is calculated based on the baseline torque of the current basic regeneration gear, combined with the scenario adjustment factor and the state adjustment factor, and the result is limited to the basic regeneration intensity range corresponding to the current basic regeneration gear.

[0104] Specifically:

[0105] T slide =T base ×(1+K′ scene +K state )

[0106] Among them, T slide is the actual recovery torque, T base is the median value of the basic torque of the current gear, K′ scene is the adjusted scenario comprehensive fine-tuning coefficient, which is obtained by superimposing the sub-coefficients of each scenario and correcting them according to the driving style characteristics:

[0107] K′ scene =(K follow +K slope +K lowv )×α

[0108] Among them, K follow is the fine-tuning coefficient for the following vehicle scenario, K slope is the fine-tuning coefficient for downhill scenes, K lowv is the low-speed scene fine-tuning coefficient, α is the driving style correction coefficient;

[0109] K state is the comprehensive fine-tuning coefficient of the state;

[0110] S4: Braking condition control: Different braking types are distinguished according to the braking operation characteristics, and corresponding energy recovery and mechanical braking coordination strategies are implemented for different braking types.

[0111] In S4, the brake operation characteristics include at least one of the following: brake pedal depression speed, brake pedal travel depth, and brake type includes normal braking and emergency braking;

[0112] For normal braking, a control strategy prioritizes energy recovery. The recovery intensity is based on the preset highest gear recovery intensity and is dynamically adjusted in combination with vehicle speed. Mechanical braking supplements insufficient braking force.

[0113] Based on the principle of "energy recovery first", the braking force is supplemented by mechanical braking;

[0114] Take the 5th gear upper limit recovery torque and dynamically limit it according to vehicle speed;

[0115] When V>60km / h, recovery torque = 60N·m;

[0116] When 30km / h<V≤60km / h, recovery torque=60×(V / 60);

[0117] When V≤30km / h, recovery torque = 30N·m;

[0118] Mechanical brake supplement:

[0119] The main controller calculates the total braking torque through the braking demand model;

[0120] For emergency braking, a safety-first control strategy is adopted, first initiating over-limit regeneration and simultaneously triggering a rapid mechanical brake response. The regeneration intensity dynamically decays as vehicle speed decreases, and at low speeds, mechanical braking is fully relied upon.

[0121] Based on the principle of "brake safety first", we maximize energy recovery while ensuring braking distance:

[0122] 0-0.3s fast response stage:

[0123] The over-limit recovery is initiated and an "emergency pressure build-up" command is sent to the wire control brake system. The mechanical brake pressure reaches 10 MPa within 0.3 seconds to ensure rapid braking.

[0124] After 0.3s, the collaborative phase:

[0125] The regenerative torque decays linearly with vehicle speed to avoid excessive motor drag at low speeds:

[0126] Mechanical braking supplements the remaining braking torque and works in conjunction with the ESP system to monitor wheel slip through wheel speed sensors and control the vehicle within the optimal braking range of 15-20%.

[0127] When the vehicle is at a low speed, such as less than or equal to 20km / h, the recovery torque drops to 0, and it relies entirely on mechanical braking to avoid the impact of reduced motor recovery efficiency on the braking effect.

[0128] The calculation formula for the instantaneous power P recovered during braking is:

[0129]

[0130] Among them, T recycle is the actual recovery torque, n is the motor speed;

[0131] Moreover, the attenuation formula of the actual recovery torque speed is:

[0132]

[0133] T recycle =0(V≤20km / h)

[0134] Among them, T max_emerg is the initial maximum recovery torque of the brake, V0 is the reference vehicle speed, and V is the real-time vehicle speed;

[0135] When it is detected that the status of a vehicle component exceeds a preset safety threshold, the recovery intensity is reduced or energy recovery is turned off;

[0136] The overall execution of this application can refer to the following systems:

[0137] Perception layer: includes accelerator pedal sensor, brake pedal sensor, millimeter-wave radar, gyroscope, wheel speed sensor, battery management system and driver behavior recorder, used to collect driver operation signals, vehicle status parameters and environmental information;

[0138] Decision layer: including a main controller and an auxiliary decision chip, used to execute the control method of any one of claims 1 to 8, perform working condition identification, gear analysis, and scene and state adaptation calculation;

[0139] The execution layer includes the drive motor and controller, the wire-controlled brake system, and the human-machine interface. It is used to receive instructions from the decision-making layer, perform coordinated control of energy recovery and mechanical braking, and provide status feedback.

[0140] A button can be set around the driver's seat. By pressing the button, the driver can prohibit system intervention and only follow the kinetic energy recovery gear set by the driver, realizing free switching between manual and automatic.

[0141] The foregoing is merely a preferred embodiment of the present invention. It should be noted that those skilled in the art may make various improvements and modifications without departing from the principles of the present invention, and such improvements and modifications are also within the scope of protection of the present invention. Structures, devices, and operating methods not specifically described or explained herein shall, unless otherwise specified or limited, be implemented in accordance with conventional means in the art.

Claims

1. A driving style-based braking energy recovery control method for a pure electric vehicle, characterized in that: The following steps are involved: S1: Operating condition identification: The sensor detects the driver's operating status and distinguishes between throttle, coasting and braking conditions; S2: Gear Setting: Provides multiple manually adjustable basic recycling gears, each gear corresponding to a preset basic recycling intensity range; S3: Coasting Control: Within the basic recuperation intensity range corresponding to the basic recuperation gear, dynamic adjustments are made based on scenario parameters and vehicle status parameters to obtain and execute the actual recuperation intensity. S4: Braking condition control: Different braking types are distinguished according to the braking operation characteristics, and corresponding energy recovery and mechanical braking coordination strategies are implemented for different braking types.

2. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 1, characterized in that: In S1, when it is detected that the accelerator pedal opening is greater than a preset threshold, it is determined to be a throttle operating condition and energy recovery is not started; When the accelerator pedal is fully released and no brake operation is detected, it is determined to be in coasting condition; When a brake operation is detected, it is determined to be a brake condition.

3. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 2, characterized in that: In S2, the basic recovery gear that can be manually adjusted in multiple stages is 5, and each gear corresponds to a different recovery torque range.

4. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 3, characterized in that: In said S3, the dynamic adjustment in the coasting condition control includes scene dimension adjustment and state dimension adjustment; The scene dimension adjustment specifically includes: Adjust the recovery intensity based on the distance to the vehicle ahead and the vehicle's speed; Adjust the recovery intensity based on the road slope; Adjust the recovery intensity and recovery start timing based on vehicle speed detection; The state dimension adjustment specifically includes: Analyze battery state of charge to adjust recycling intensity; Adjust the adjustment amplitude of the scene dimension based on driving style characteristics.

5. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 4, characterized in that: In S3, under the coasting control condition, the actual regeneration torque is calculated by taking the reference torque of the current basic regeneration gear as a basis, combining the scene adjustment coefficient and the state adjustment coefficient, and limiting the calculation result to the basic regeneration intensity range corresponding to the current basic regeneration gear; Specifically: T slide =T base ×(1+K′ scene +K state ) Among them, T slide is the actual recovery torque, T base is the median value of the basic torque of the current gear, K′ scene is the adjusted scenario comprehensive fine-tuning coefficient, which is obtained by superimposing the sub-coefficients of each scenario and correcting them according to the driving style characteristics: K′ scene =(K follow +K slope +K lowv )×α Among them, K follow is the fine-tuning coefficient for the following vehicle scenario, K slope is the fine-tuning coefficient for downhill scenes, K lowv is the low-speed scene fine-tuning coefficient, α is the driving style correction coefficient; K state is the comprehensive fine-tuning coefficient of the state.

6. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 5, characterized in that: In S4, the braking operation characteristics include at least one of the following: a brake pedal depression speed, a brake pedal travel depth, and the braking type includes normal braking and emergency braking; For the ordinary brake, a control strategy with energy recovery priority is adopted. The recovery intensity is based on the preset highest gear recovery intensity and is dynamically adjusted in combination with the vehicle speed. Mechanical braking supplements the insufficient braking force. For the emergency brake, a safety-first control strategy is adopted, which first starts the over-limit recovery and triggers the mechanical brake to respond quickly. The recovery intensity dynamically decays as the vehicle speed decreases, and at low speeds, it relies entirely on mechanical braking.

7. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 6, characterized in that: The calculation formula for the instantaneous power P recovered during braking is: Among them, T recycle is the actual recovery torque, n is the motor speed; Moreover, the attenuation formula of the actual recovery torque vehicle speed is: T recycle =0(V≤20km / h) Among them, T max_emerg is the initial maximum recovery torque of the brake, V0 is the reference vehicle speed, and V is the real-time vehicle speed.

8. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 1, characterized in that: It also includes a protection mechanism that reduces the recovery intensity or turns off energy recovery when it detects that the status of vehicle components exceeds a preset safety threshold.

9. The method for controlling braking energy recovery of a pure electric vehicle based on driving style according to claim 1, characterized in that: The sensors include an accelerator pedal sensor, a brake pedal sensor, a distance detection sensor, a slope sensor, a vehicle speed sensor, a battery status monitoring module, and a driving behavior recording module.

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