Brake linkage sliding energy recovery method and device, vehicle and storage medium

Abstract

The invention relates to the technical field of vehicle control, in particular to a brake linkage sliding energy recovery method and device, a vehicle and a storage medium. The method comprises the steps that under the condition that a brake pedal displacement signal is detected, the displacement speed of a brake pedal and the springback speed of the brake pedal are obtained based on the brake pedal displacement signal; according to the displacement speed and the rebound speed of the brake pedal, whether the brake pedal meets a preset release condition or not is judged; and under the condition that the brake pedal meets the preset release condition, filtering processing is conducted on the brake pedal displacement signal, and based on the processed brake pedal displacement signal, the current sliding energy recovery torque of the vehicle is controlled to conduct sliding energy recovery according to the preset torque condition. Therefore, the problem that the vehicle cannot respond in time under the working condition that the vehicle is controlled to quickly turn from deceleration to acceleration can be solved, user experience is improved, and driving safety is guaranteed.

Description

Technical Field

[0001] The present application relates to the field of vehicle control technology, and in particular to a brake-linked coasting energy recovery method, device, vehicle and storage medium. Background Art

[0002] With the development of society, energy crisis and environmental pollution have become important factors restricting economic development. As an effective way to solve such problems, electric vehicles have received great attention from governments and the vehicle industry. Compared with traditional vehicles, the driving range of electric vehicles is generally not high due to the low energy density of batteries, so the energy saving of electric vehicles has become a research focus. In order to maximize energy saving, most electric vehicles currently have energy recovery technologies, mainly the following two: the first is to use the electric vehicle to convert the motor from the electric state to the power generation state when braking, so that the motor's power generation energy is recovered to the battery to increase the driving range of the electric vehicle; the other is to make full use of the sliding moment of the electric vehicle, so that the vehicle is converted from the natural sliding state to the braking sliding state, so that the motor runs in the power generation state to increase the driving range.

[0003] However, the existing coasting energy recovery strategies all perform coasting energy recovery when the driver completely releases the accelerator pedal and does not step on the brake pedal. When the driver intends to control the vehicle to quickly turn from deceleration to acceleration, the existence of coasting energy recovery makes it impossible to respond in time under the condition of controlling the vehicle to quickly turn from deceleration to acceleration, which urgently needs to be solved. Summary of the invention

[0004] The present application provides a brake-linked coasting energy recovery method, device, vehicle and storage medium to solve the problem of failure to respond in time when controlling a vehicle to quickly shift from deceleration to acceleration, thereby improving user experience and ensuring driving safety.

[0005] To achieve the above-mentioned purpose, a first embodiment of the present application provides a braking-linked sliding energy recovery method, comprising the following steps:

[0006] Determining whether a brake pedal displacement signal is detected;

[0007] When the brake pedal displacement signal is detected, obtaining a displacement speed of the brake pedal and a rebound speed of the brake pedal based on the brake pedal displacement signal;

[0008] judging whether the brake pedal meets a preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal;

[0009] When the brake pedal meets the preset release condition, filter the brake pedal displacement signal, and based on the processed brake pedal displacement signal, control the current coasting energy recovery torque of the vehicle to perform coasting energy recovery according to the preset torque condition.

[0010] According to an embodiment of the present application, determining whether the brake pedal meets the preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal includes:

[0011] Judge whether the displacement speed of the brake pedal is greater than or equal to a first preset threshold, and judge whether the rebound speed of the brake pedal is greater than or equal to a second preset threshold;

[0012] When the displacement speed of the brake pedal is greater than or equal to the first preset threshold and the rebound speed of the brake pedal is greater than or equal to the second preset threshold, obtain the interval duration between the moment when the displacement speed of the brake pedal is equal to the first preset threshold and the moment when the rebound speed of the brake pedal is equal to the second preset threshold;

[0013] Judge whether the interval duration is less than a preset duration;

[0014] If the interval duration is less than the preset duration, it is determined that the brake pedal meets the preset release condition, otherwise it is determined that the brake pedal does not meet the preset release condition.

[0015] According to an embodiment of the present application, after determining whether the brake pedal meets the preset release condition, it further includes:

[0016] If the brake pedal does not meet the preset release condition, obtain the current speed of the vehicle;

[0017] Based on the current speed and a preset mapping table, determine the target coasting energy recovery torque of the vehicle to control the vehicle to perform coasting energy recovery based on the target coasting energy recovery torque.

[0018] According to an embodiment of the present application, before determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping table, it further includes:

[0019] Use a test bench to perform coasting resistance tests and energy recovery tests;

[0020] Group the test data according to vehicle speed, and based on the coasting resistance test results and energy recovery test results, determine the torque value with the largest increase in motor recovery torque and the smoothest deceleration in each test data group as the base torque matching each test data group;

[0021] The preset mapping relation table is obtained based on each of the test data groups and the base torque matching each of the test data groups.

[0022] According to an embodiment of the present application, when determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping relation table, it further includes:

[0023] Obtain the current battery SOC (State of Charge), the current battery temperature, the current wheel speed difference, and the current acceleration of the vehicle;

[0024] Perform a moving average filtering process on the current battery SOC and the current battery temperature to obtain processed battery state data, and perform a Kalman filtering process on the current wheel speed difference and the current acceleration to obtain processed road surface condition data;

[0025] Based on the processed road surface condition data, use an extremum search algorithm to determine the road surface friction coefficient, and based on the processed battery state data and the road surface friction coefficient, use a PID (Proportional-Integral-Derivative) strategy to adjust the target coasting energy recovery torque to obtain a new target coasting energy recovery torque.

[0026] According to the braking linkage coasting energy recovery method proposed in the embodiment of the present application, when a braking pedal displacement signal is detected, the displacement speed and the rebound speed of the braking pedal are obtained based on the braking pedal displacement signal; according to the displacement speed and the rebound speed of the braking pedal, it is determined whether the braking pedal meets a preset release condition; when the braking pedal meets the preset release condition, the braking pedal displacement signal is filtered, and based on the processed braking pedal displacement signal, the current coasting energy recovery torque of the vehicle is controlled to perform coasting energy recovery according to a preset torque condition. Thus, the problem that the vehicle cannot respond in a timely manner under the condition of quickly changing from deceleration to acceleration can be solved, the user experience is improved, and driving safety is ensured.

[0027] To achieve the above object, an embodiment of the second aspect of the present application proposes a braking linkage coasting energy recovery device, including:

[0028] A first judgment module, configured to judge whether a braking pedal displacement signal is detected;

[0029] An acquisition module, configured to, when the braking pedal displacement signal is detected, obtain the displacement speed and the rebound speed of the braking pedal based on the braking pedal displacement signal;

[0030] A second judgment module, configured to judge whether the brake pedal meets a preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal;

[0031] A control module, configured to, when the brake pedal meets the preset release condition, perform filtering processing on the brake pedal displacement signal, and based on the processed brake pedal displacement signal, control the current coasting energy recovery torque of the vehicle to perform coasting energy recovery according to a preset torque condition.

[0032] According to an embodiment of the present application, the second judgment module is specifically configured to:

[0033] Judge whether the displacement speed of the brake pedal is greater than or equal to a first preset threshold, and judge whether the rebound speed of the brake pedal is greater than or equal to a second preset threshold;

[0034] When the displacement speed of the brake pedal is greater than or equal to the first preset threshold and the rebound speed of the brake pedal is greater than or equal to the second preset threshold, obtain the interval duration between the moment when the displacement speed of the brake pedal is equal to the first preset threshold and the moment when the rebound speed of the brake pedal is equal to the second preset threshold;

[0035] Judge whether the interval duration is less than a preset duration;

[0036] If the interval duration is less than the preset duration, it is determined that the brake pedal meets the preset release condition; otherwise, it is determined that the brake pedal does not meet the preset release condition.

[0037] According to an embodiment of the present application, after judging whether the brake pedal meets the preset release condition, the control module further includes:

[0038] An acquisition unit, configured to acquire the current speed of the vehicle under the condition that the brake pedal does not meet the preset release condition;

[0039] A determination unit, configured to determine the target coasting energy recovery torque of the vehicle based on the current speed and a preset mapping relation table, so as to control the vehicle to perform coasting energy recovery based on the target coasting energy recovery torque.

[0040] According to an embodiment of the present application, before determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping relation table, the determination unit is further configured to:

[0041] Use a test bench to perform coasting resistance tests and energy recovery tests;

[0042] Group the test data according to the vehicle speed, and based on the coasting resistance test results and the energy recovery test results, determine the torque value with the largest increase in the motor recovery torque and the smoothest deceleration in each test data group as the base torque matching each test data group;

[0043] Obtain the preset mapping relation table based on each test data group and the base torque matching each test data group.

[0044] According to an embodiment of the present application, when determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping relation table, the determining unit is further configured to:

[0045] Obtain the current battery SOC, the current battery temperature, the current wheel speed difference and the current acceleration of the vehicle;

[0046] Perform a moving average filtering process on the current battery SOC and the current battery temperature to obtain processed battery state data, and perform a Kalman filtering process on the current wheel speed difference and the current acceleration to obtain processed road condition data;

[0047] Based on the processed road condition data, use the extremum search algorithm to determine the road surface friction coefficient, and based on the processed battery state data and the road surface friction coefficient, use the PID strategy to adjust the target coasting energy recovery torque to obtain a new target coasting energy recovery torque.

[0048] According to the braking linkage coasting energy recovery device proposed in the embodiment of the present application, when a braking pedal displacement signal is detected, the displacement speed and the rebound speed of the braking pedal are obtained based on the braking pedal displacement signal; according to the displacement speed and the rebound speed of the braking pedal, it is determined whether the braking pedal meets the preset release condition; when the braking pedal meets the preset release condition, perform a filtering process on the braking pedal displacement signal, and based on the processed braking pedal displacement signal, control the current coasting energy recovery torque of the vehicle to perform coasting energy recovery according to the preset torque condition. Thus, the problem that the vehicle cannot respond in time under the condition of quickly changing from deceleration to acceleration can be solved, the user experience can be improved, and the driving safety can be guaranteed.

[0049] To achieve the above object, an embodiment of the third aspect of the present application proposes a vehicle, including: a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the program to implement the braking linkage coasting energy recovery method as described in the above embodiment.

[0050] To achieve the above object, an embodiment of the fourth aspect of the present application provides a computer-readable storage medium, on which a computer program is stored, and the program is executed by a processor to implement the braking linkage coasting energy recovery method as described in the above embodiments.

[0051] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0053] Figure 1 is a flowchart of a braking linkage coasting energy recovery method according to an embodiment of the present application;

[0054] Figure 2 is a schematic diagram of an image of the release and rebound of the brake pedal stroke according to an embodiment of the present application;

[0055] Figure 3 is a block diagram of a braking linkage coasting energy recovery device according to an embodiment of the present application;

[0056] Figure 4 is a schematic diagram of the structure of a vehicle according to an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0057] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present application, and should not be construed as limiting the present application.

[0058] The braking linkage coasting energy recovery method, device, vehicle, and storage medium according to embodiments of the present application will be described below with reference to the accompanying drawings. First, the braking linkage coasting energy recovery method according to embodiments of the present application will be described with reference to the accompanying drawings.

[0059] Figure 1 is a flowchart of a braking linkage coasting energy recovery method according to an embodiment of the present application.

[0060] Exemplarily, as Figure 1 shown, the braking linkage coasting energy recovery method includes the following steps:

[0061] In step S101, it is determined whether a brake pedal displacement signal is detected.

[0062] It can be understood that the brake pedal displacement signal refers to the signal that can be collected when the position of the brake pedal changes. There are many ways to detect the brake pedal displacement signal, including but not limited to: mechanical sensor detection, that is, using a mechanical structure to convert the displacement of the brake pedal into an electrical signal. For example, by installing a sliding rheostat on the connecting rod of the brake pedal, when the brake pedal is depressed or released, the position of the sliding contact of the sliding rheostat will change, resulting in a change in its resistance value, and then generating different electrical signals. Electronic sensor detection, including potentiometer sensors and magnetic induction sensors, etc. In a potentiometer sensor, the brake pedal is connected to the sliding contact of the potentiometer through a connecting rod. When the position of the brake pedal changes, the sliding contact slides on the resistor body of the potentiometer, and a voltage signal proportional to the displacement can be output. In a magnetic induction sensor, a magnet and a magneto-sensitive element, such as a Hall sensor, are installed near the brake pedal. When the brake pedal moves, the relative position between the magnet and the magneto-sensitive element changes, and the magnetic field intensity sensed by the magneto-sensitive element also changes accordingly, thereby outputting a corresponding electrical signal to reflect the displacement of the brake pedal.

[0063] In step S102, when the brake pedal displacement signal is detected, based on the brake pedal displacement signal, the displacement speed of the brake pedal and the rebound speed of the brake pedal are obtained.

[0064] It can be understood that the displacement speed of the brake pedal refers to the change amount of the pedal position per unit time during the process of depressing or releasing the brake pedal, which reflects the speed at which the driver depresses or releases the brake pedal. In the embodiment of the present application, the displacement speed of the brake pedal specifically refers to the manifestation form in the release direction of the brake pedal. When the driver quickly releases the brake pedal, the brake pedal will not only have a rapid release speed but also a corresponding rebound speed. The rebound speed of the brake pedal refers to the speed at which the brake pedal returns to the non-depressed position under its own resilience after the driver releases the brake pedal, that is, the rate of change of its position during the process of the brake pedal returning from the depressed position to the initial position.

[0065] Since only relying on the release speed cannot fully and accurately judge the driver's intention, there may be other factors causing the pedal to release quickly, but it does not necessarily mean that the driver intends to accelerate quickly. By simultaneously detecting the release speed and the rebound speed of the brake pedal, it is possible to more accurately judge whether the driver intends to quickly switch from the deceleration state to the acceleration state, increasing the reliability and accuracy of the judgment.

[0066] Specifically, in the braking system of a vehicle, when the driver quickly releases the brake pedal and a brake pedal displacement signal is detected, the brake pedal displacement signal can be converted into an electrical signal and transmitted to the vehicle's control module, such as the Body Control Module (BCM) or the Powertrain Control Module (PCM), etc., via the vehicle's CAN (Controller Area Network) bus or other communication buses. After receiving the relevant signal, the vehicle's control module parses and processes it to obtain parameters such as the displacement information of the brake pedal, the displacement speed (i.e., the release speed), and the rebound speed, etc.

[0067] In step S103, according to the displacement speed of the brake pedal and the rebound speed of the brake pedal, it is determined whether the brake pedal meets the preset release condition.

[0068] Among them, the preset release condition refers to the driver's intention to quickly release the brake pedal, that is, the intention to quickly switch from a decelerating state to an accelerating state.

[0069] That is to say, according to the displacement speed of the brake pedal (i.e., the release speed) and the rebound speed of the brake pedal, it can be determined whether the driver intends to quickly release the brake pedal (i.e., whether the brake pedal meets the preset release condition).

[0070] For ease of understanding, the following details how to determine whether the brake pedal meets the preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal.

[0071] As a possible implementation method, in some embodiments, determining whether the brake pedal meets the preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal includes: determining whether the displacement speed of the brake pedal is greater than or equal to a first preset threshold, and determining whether the rebound speed of the brake pedal is greater than or equal to a second preset threshold; when the displacement speed of the brake pedal is greater than or equal to the first preset threshold and the rebound speed of the brake pedal is greater than or equal to the second preset threshold, obtaining the interval duration between the moment when the displacement speed of the brake pedal is equal to the first preset threshold and the moment when the rebound speed of the brake pedal is equal to the second preset threshold; determining whether the interval duration is less than a preset duration; if the interval duration is less than the preset duration, it is determined that the brake pedal meets the preset release condition, otherwise it is determined that the brake pedal does not meet the preset release condition.

[0072] Among them, the first preset threshold, the second preset threshold, and the preset duration can all be preset by researchers in this field, can also be obtained through a limited number of experiments, or can be obtained through a limited number of computer simulations. No specific limitation is made here.

[0073] Specifically, first, the displacement speed of the brake pedal (i.e., the release speed) can be detected to determine whether it reaches or exceeds a first preset threshold (such as Figure 2 the pedal release speed threshold shown); at the same time, the rebound speed of the brake pedal can also be evaluated to determine whether it reaches or exceeds a second preset threshold (such as Figure 2 the pedal rebound speed threshold shown). When the displacement speed of the brake pedal (i.e., the release speed) reaches the first preset threshold, it indicates that the driver releases the brake pedal relatively quickly, and there may be an intention to quickly release the brake pedal (i.e., an intention to quickly switch from the deceleration state to the acceleration state). And when the rebound speed of the brake pedal also reaches the second preset threshold, it further strengthens the possibility of the intention to quickly release the brake pedal. Next, record the specific moment when the displacement speed of the brake pedal (i.e., the release speed) reaches the first preset threshold, and the specific moment when the rebound speed of the brake pedal reaches the second preset threshold. Subsequently, calculate the time interval between these two moments. If the duration of this time interval is less than the preset duration, it indicates that these two actions are continuous and almost occur simultaneously, then it can be determined that the brake pedal meets the preset release condition, that is, it is determined that the driver's intention is to quickly release the brake pedal. Otherwise, it can be determined that the brake pedal does not meet the preset release condition.

[0074] In step S104, when the brake pedal meets the preset release condition, filter the brake pedal displacement signal, and based on the processed brake pedal displacement signal, control the current coasting energy recovery torque of the vehicle to perform coasting energy recovery according to the preset torque condition.

[0075] Specifically, after determining that the driver's intention is to quickly release the brake pedal, due to phenomena such as rebound during the release of the brake pedal, interference exists in the brake pedal displacement signal, so it needs to be filtered to remove these interference signals and more accurately obtain the true pedal displacement situation.

[0076] In order to promptly respond to the driver's demand for the vehicle to quickly switch from the deceleration state to the acceleration state and avoid the braking torque generated by the coasting energy recovery system from hindering or delaying the vehicle's acceleration, the current coasting energy recovery torque of the vehicle can be adjusted to meet the preset torque condition, that is, limit the coasting energy recovery torque to 0 N·m, so that the vehicle can start accelerating more quickly.

[0077] Further, in some other embodiments, after determining whether the brake pedal meets the preset release condition, it further includes: if the brake pedal does not meet the preset release condition, obtaining the current speed of the vehicle; based on the current speed and a preset mapping relation table, determining the target coasting energy recovery torque of the vehicle to control the vehicle to perform coasting energy recovery based on the target coasting energy recovery torque.

[0078] It can be understood that the preset mapping relation table refers to a mapping table used to describe the basic motor recovery torque output by the motor of the vehicle at different vehicle speeds.

[0079] That is to say, if it is determined that the brake pedal does not meet the preset release condition, that is, it is determined that the driver's intention is not to quickly release the brake pedal, indicating that the vehicle is in a normal braking or coasting state, then the corresponding coasting recovery torque can be executed according to the current speed of the vehicle and the preset mapping relation table (i.e., the vehicle speed - basic torque table) generated in advance through experimental tests, etc., to achieve effective energy recovery.

[0080] Next, how to obtain the preset mapping relation table will be described in detail.

[0081] Optionally, in some embodiments, before determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping relation table, it further includes: performing a coasting resistance test and an energy recovery test using a test bench; grouping the test data according to the vehicle speed, and based on the coasting resistance test result and the energy recovery test result, determining the torque value with the largest increase in the motor recovery torque and the smoothest deceleration in each test data group as the basic torque matching each test data group; obtaining the preset mapping relation table based on each test data group and the basic torque matching each test data group.

[0082] Specifically, by using a specially designed test bench, coasting resistance tests and energy recovery tests can be conducted to ensure the accuracy and comprehensiveness of the tests. In the embodiments of the present application, the equipment used in the test bench includes: a chassis dynamometer, a high-precision torque sensor, a battery BMS (Battery Management System), and a CAN bus recorder. Among them, the chassis dynamometer is used to simulate the driving conditions of the vehicle at different vehicle speeds and loads, the high-precision torque sensor is used to accurately measure the recovery torque of the motor, the battery BMS is used to monitor the state of the battery, and the CAN bus recorder is used to record the data transmission of each system of the vehicle during the test. The test conditions are set as follows: the ambient temperature is 25±2°C under standard conditions, but it also needs to be extended to -30°C to 50°C for verification to ensure the applicability and stability of the data in different temperature environments. The vehicle states include three cases: no load, half load, and full load, and the tire pressure is maintained at 2.5 bar. The road surface simulation conditions include simulating dry roads (friction coefficient μ = 0.8), wet roads (μ = 0.4), and ice surfaces (μ = 0.1), etc., to consider the influence of different road surface adhesion coefficients on energy recovery.

[0083] Next, conduct the coasting resistance test. First, turn off the energy recovery system, control the vehicle to start coasting at different initial speeds (such as 10 km / h, 20 km / h, 30 km / h,..., 80 km / h), and record the deceleration a of the vehicle at this time. coast . According to Newton's second law, calculate the total resistance F total = m·a coast , where m is the curb weight of the vehicle. Then, by fitting the resistance formula F total = k1 + k2v + k3v 2 , determine the coefficients k1, k2, and k3 in the formula, so that the coasting resistance characteristics of the vehicle at different vehicle speeds can be obtained, providing basic resistance data for subsequent determination of the energy recovery torque.

[0084] Subsequently, conduct the energy recovery test. Simulate various vehicle speeds on the chassis dynamometer, and then gradually increase the recovery torque T of the motor regen , record the actual deceleration a of the vehicle at this time regen and the charging power P of the battery regen . The charging power P of the battery regen = T regen ·ω motor ·η motor , where ω motor is the motor speed, and η motor is the motor efficiency. At the same time, adjust the torque to meet certain constraint conditions, that is, the deceleration change rate Δa / Δt ≤ 0.5 m / s 3, to avoid the vehicle from being impacted due to too rapid change in deceleration, which may affect the riding comfort and safety of users; and control the battery charging current not to exceed the maximum allowable value (such as C / 2) to prevent overcharging of the battery and protect the safety and lifespan of the battery.

[0085] Group the test data obtained from the above test process according to vehicle speed, for example, every 5 km / h as a group. In each group of data, select the torque value that makes the battery charging power P regen maximum, while the actual deceleration a of the vehicle regen is relatively smooth (i.e., meets the above constraint conditions), as the base torque corresponding to this vehicle speed. Thus, the base torque values corresponding to different vehicle speeds are obtained, and a preset mapping relationship table is generated, as shown in Table 1.

[0086] Table 1

[0087] Vehicle speed (km / h) Base torque (N·m) <![CDATA[Deceleration (m / s 2 )]]> Recovery power (kW) 20 60 0.8 1.2 40 120 1.0 3.5 60 180 1.2 6.8

[0088] Optionally, in some embodiments, when determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping relationship table, it further includes: obtaining the current battery SOC, current battery temperature, current wheel speed difference, and current acceleration of the vehicle; performing a moving average filtering process on the current battery SOC and current battery temperature to obtain the processed battery state data, and performing a Kalman filtering process on the current wheel speed difference and current acceleration to obtain the processed road condition data; determining the road surface friction coefficient based on the processed road condition data by using an extremum search algorithm, and adjusting the target coasting energy recovery torque by using a PID strategy based on the processed battery state data and the road surface friction coefficient to obtain a new target coasting energy recovery torque.

[0089] It can be understood that in order to effectively improve the energy recovery efficiency during the actual operation of the vehicle and ensure the driving safety and stability of the vehicle, the coasting energy recovery torque can be dynamically adjusted according to various current states and environmental conditions of the vehicle.

[0090] Specifically, first, the real-time detection parameters monitor and collect data. The monitoring objects include: (1) Battery status, ① The current battery SOC can be obtained through the BMS, and its accuracy needs to reach ±2% to accurately grasp the remaining battery power; ② The current battery temperature can be monitored by temperature sensors at key positions (such as battery cells, coolant) to ensure that the battery operates within an appropriate temperature range. (2) Motor system, ① Obtain the motor speed and torque output value in real time to understand the operating state of the motor; ② The real-time efficiency of the motor can be calculated through current and voltage (efficiency = output power / input power). (3) Road surface conditions, ① The wheel speed difference can be calculated through wheel speed sensors and identify slipping situations (such as when the speed of one side of the wheel exceeds 5% of the other side, it is determined as unilateral slipping) to identify the road surface adhesion; ② The longitudinal acceleration (i.e., the current acceleration) can be obtained through an acceleration sensor (Inertial Measurement Unit, abbreviated as IMU) to assist in judging the road surface adhesion coefficient. (4) Environmental parameters, including vehicle speed, gear position, brake pedal status (such as whether it is depressed), etc. To ensure the real-time and accuracy of the data, the data collection frequency is set as follows: Key parameters (such as SOC, wheel speed, etc.) need to be sampled at a frequency of more than 100Hz to ensure real-time, and the CAN bus or FlexRay high-speed communication protocol can be used to transmit data to meet the requirements of fast and reliable data interaction.

[0091] Then, since the collected data may be affected by noise interference or abnormal values, the parameter data obtained in the previous step can be filtered. For slow-changing signals such as the current battery SOC and the current battery temperature, a 5-point moving average (i.e., moving average filtering) can be used to eliminate high-frequency noise, thereby obtaining the processed battery status data; for dynamic signals such as the current wheel speed difference and the current acceleration, Kalman filtering is performed to reduce measurement errors and improve the accuracy of the data, thereby obtaining the processed road surface condition data. In addition, reasonable threshold ranges are set for each parameter. For example, the normal range of SOC is 20% - 90%. If the SOC exceeds this range, the fault mode is triggered and corresponding safety measures are taken. For example, when the SOC exceeds 95%, to avoid overcharging the battery, the regenerative torque is forcibly limited to 0 N·m.

[0092] Finally, based on the processed road surface condition data and the processed battery state data, and combined with the multi-parameter fusion rule, the coasting energy recovery torque is dynamically adjusted. Specifically, the battery priority strategy: when the SOC is lower than 30%, it indicates that the battery power is low. At this time, the recovery torque can be increased by 20%-30% to increase the energy recovery intensity and quickly charge the battery; when the SOC exceeds 80%, to prevent overcharging of the battery, the recovery torque is reduced by 50% or the energy recovery function is directly disabled. Estimation of road surface friction coefficient: Combining the processed road surface condition data (wheel speed difference and longitudinal acceleration information), the neural network model or the extremum search algorithm is used to estimate the road surface friction coefficient μ value in real time. According to different μ value ranges, the recovery torque is restricted accordingly. For example, on a dry road surface with μ>0.5, the maximum allowable recovery torque is permitted; on a wet road surface with 0.3<μ≤0.5, the recovery torque is restricted to 70%; on an ice surface with μ≤0.3, it is restricted to 30% to ensure the driving stability and safety of the vehicle under different road surface conditions. Motor efficiency optimization: Calculate the efficiency curve of the motor in real time and select the operating point with the highest motor efficiency. If the operating point with the highest motor efficiency is lower than 85%, the recovery torque is reduced to avoid energy waste caused by low motor efficiency.

[0093] Among them, in the process of dynamically adjusting the coasting energy recovery torque based on the processed road surface condition data and the processed battery state data, and combined with the multi-parameter fusion rule, the PID control algorithm can be used to achieve precise control of the energy recovery torque. Specifically, first, the basic recovery torque value obtained based on the look-up table method is used as the target recovery torque T target , and the actual recovery torque T actual is calculated and output through the PID control algorithm, so that the actual recovery torque can accurately track the target recovery torque. Secondly, the proportional term (P) can adjust the gain according to the deviation of the SOC. For example, K p = 0.5×(1 - SOC), so that the weight of the proportional term can be dynamically adjusted according to the current battery power state; the integral term (I) is mainly used to compensate for the long-term deviation in the system. For example, when the battery temperature is too high, the integral term is saturated and limited to prevent the integral term from being too large and causing system instability; the derivative term (D) can predict sudden changes in the road surface. For example, when there is a sudden change in the wheel speed difference, the value of the derivative term is increased, thereby quickly reducing the recovery torque to cope with sudden changes in the road surface adhesion conditions and ensuring the smoothness of vehicle driving. Thus, through the establishment of the multi-parameter fusion rule and the PID control algorithm, the adaptive adjustment of the energy recovery torque is achieved.

[0094] According to the braking linkage coasting energy recovery method proposed by the embodiments of the present application, when a brake pedal displacement signal is detected, the displacement speed of the brake pedal and the rebound speed of the brake pedal are obtained based on the brake pedal displacement signal; according to the displacement speed and the rebound speed of the brake pedal, it is determined whether the brake pedal meets a preset release condition; when the brake pedal meets the preset release condition, the brake pedal displacement signal is filtered, and based on the processed brake pedal displacement signal, the current coasting energy recovery torque of the vehicle is controlled to perform coasting energy recovery according to a preset torque condition. Thus, the problem that the vehicle cannot respond in time under the condition of quickly changing from deceleration to acceleration can be solved, the user experience is improved, and the driving safety is guaranteed.

[0095] Next, a braking linkage coasting energy recovery device according to an embodiment of the present application will be described with reference to the accompanying drawings.

[0096] Figure 3 It is a block diagram of a braking linkage coasting energy recovery device according to an embodiment of the present application.

[0097] As Figure 3 shown, the braking linkage coasting energy recovery device 10 includes: a first judgment module 100, an acquisition module 200, a second judgment module 300, and a control module 400.

[0098] Among them, the first judgment module 100 is used to judge whether a brake pedal displacement signal is detected;

[0099] The acquisition module 200 is used to, when a brake pedal displacement signal is detected, obtain the displacement speed of the brake pedal and the rebound speed of the brake pedal based on the brake pedal displacement signal;

[0100] The second judgment module 300 is used to judge whether the brake pedal meets a preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal;

[0101] The control module 400 is used to, when the brake pedal meets the preset release condition, filter the brake pedal displacement signal, and based on the processed brake pedal displacement signal, control the current coasting energy recovery torque of the vehicle to perform coasting energy recovery according to a preset torque condition.

[0102] Optionally, in some embodiments, the second judgment module 300 is specifically used for:

[0103] judging whether the displacement speed of the brake pedal is greater than or equal to a first preset threshold, and judging whether the rebound speed of the brake pedal is greater than or equal to a second preset threshold;

[0104] When the displacement speed of the brake pedal is greater than or equal to a first preset threshold and the rebound speed of the brake pedal is greater than or equal to a second preset threshold, obtain the interval duration between the moment when the displacement speed of the brake pedal is equal to the first preset threshold and the moment when the rebound speed of the brake pedal is equal to the second preset threshold;

[0105] Determine whether the interval duration is less than a preset duration;

[0106] If the interval duration is less than the preset duration, it is determined that the brake pedal meets the preset release condition, otherwise it is determined that the brake pedal does not meet the preset release condition.

[0107] Optionally, in some embodiments, after determining whether the brake pedal meets the preset release condition, the control module 400 further includes:

[0108] An acquisition unit, configured to acquire the current speed of the vehicle when the brake pedal does not meet the preset release condition;

[0109] A determination unit, configured to determine the target coasting energy recovery torque of the vehicle based on the current speed and a preset mapping relation table, so as to control the vehicle to perform coasting energy recovery based on the target coasting energy recovery torque.

[0110] Optionally, in some embodiments, before determining the target coasting energy recovery torque of the vehicle based on the current speed and a preset mapping relation table, the determination unit is further configured to:

[0111] Perform a coasting resistance test and an energy recovery test using a test bench;

[0112] Group the test data according to the vehicle speed, and based on the coasting resistance test result and the energy recovery test result, determine the torque value with the largest increase in the motor recovery torque and the smoothest deceleration in each test data group as the base torque matching each test data group;

[0113] Obtain a preset mapping relation table based on each test data group and the base torque matching each test data group.

[0114] Optionally, in some embodiments, when determining the target coasting energy recovery torque of the vehicle based on the current speed and a preset mapping relation table, the determination unit is further configured to:

[0115] Obtain the current battery SOC, the current battery temperature, the current wheel speed difference, and the current acceleration of the vehicle;

[0116] Perform a moving average filtering process on the current battery SOC and the current battery temperature to obtain processed battery state data, and perform a Kalman filtering process on the current wheel speed difference and the current acceleration to obtain processed road condition data;

[0117] Based on the processed road surface condition data, the extreme value search algorithm is used to determine the road surface friction coefficient, and based on the processed battery state data and the road surface friction coefficient, the PID strategy is used to adjust the target coasting energy recovery torque to obtain a new target coasting energy recovery torque.

[0118] It should be noted that the foregoing explanation of the braking linkage coasting energy recovery method embodiment is also applicable to the braking linkage coasting energy recovery device of this embodiment, and will not be elaborated here.

[0119] According to the braking linkage coasting energy recovery device proposed in the embodiments of the present application, when the brake pedal displacement signal is detected, the displacement speed of the brake pedal and the rebound speed of the brake pedal are obtained based on the brake pedal displacement signal; according to the displacement speed and the rebound speed of the brake pedal, it is judged whether the brake pedal meets the preset release condition; when the brake pedal meets the preset release condition, the brake pedal displacement signal is filtered, and based on the processed brake pedal displacement signal, the current coasting energy recovery torque of the vehicle is controlled to perform coasting energy recovery according to the preset torque condition. Thus, the problem that the vehicle cannot respond in time under the condition of quickly changing from deceleration to acceleration can be solved, the user experience is improved, and the driving safety is guaranteed.

[0120] Figure 4 The structural schematic diagram of the vehicle provided by the embodiments of the present application. The vehicle may include:

[0121] A memory 401, a processor 402, and a computer program stored on the memory 401 and executable on the processor 402.

[0122] When the processor 402 executes the program, it implements the braking linkage coasting energy recovery method provided in the above embodiments.

[0123] Further, the vehicle further includes:

[0124] A communication interface 403 for communication between the memory 401 and the processor 402.

[0125] The memory 401 is used to store a computer program executable on the processor 402.

[0126] The memory 401 may include a high-speed RAM (Random Access Memory) memory, and may also include a non-volatile memory, such as at least one disk memory.

[0127] If the memory 401, the processor 402, and the communication interface 403 are implemented independently, the communication interface 403, the memory 401, and the processor 402 can be interconnected through a bus and communicate with each other. The bus can be an ISA (Industry Standard Architecture) bus, a PCI (Peripheral Component Interconnect) bus, an EISA (Extended Industry Standard Architecture) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 4 only a thick line is used to represent it in Figure 4 , but it does not mean that there is only one bus or one type of bus.

[0128] Optionally, in specific implementation, if the memory 401, the processor 402, and the communication interface 403 are integrated on a single chip, the memory 401, the processor 402, and the communication interface 403 can communicate with each other through an internal interface.

[0129] The processor 402 may be a CPU (Central Processing Unit), or an ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement the embodiments of the present application.

[0130] The embodiments of the present application also provide a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the braking linkage coasting energy recovery method as described above is implemented.

[0131] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present application, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0132] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of this application. In this specification, the schematic expressions of the above terms are not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0133] Although the embodiments of this application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting this application. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A braking linkage coasting energy recovery method, characterized in that, It includes the following steps: Judge whether a brake pedal displacement signal is detected; When the brake pedal displacement signal is detected, based on the brake pedal displacement signal, obtain the displacement speed of the brake pedal and the rebound speed of the brake pedal; According to the displacement speed of the brake pedal and the rebound speed of the brake pedal, judge whether the brake pedal meets the preset release condition; When the brake pedal meets the preset release condition, perform filtering processing on the brake pedal displacement signal, and based on the processed brake pedal displacement signal, control the current coasting energy recovery torque of the vehicle to perform coasting energy recovery according to the preset torque condition.

2. The method according to claim 1, characterized in that, The step of judging whether the brake pedal meets the preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal includes: Judge whether the displacement speed of the brake pedal is greater than or equal to a first preset threshold value, and judge whether the rebound speed of the brake pedal is greater than or equal to a second preset threshold value; When the displacement speed of the brake pedal is greater than or equal to the first preset threshold value and the rebound speed of the brake pedal is greater than or equal to the second preset threshold value, obtain the interval duration between the moment when the displacement speed of the brake pedal is equal to the first preset threshold value and the moment when the rebound speed of the brake pedal is equal to the second preset threshold value; Judge whether the interval duration is less than a preset duration; If the interval duration is less than the preset duration, it is determined that the brake pedal meets the preset release condition, otherwise it is determined that the brake pedal does not meet the preset release condition.

3. The method according to claim 1, wherein After judging whether the brake pedal meets the preset release condition, it further includes: If the brake pedal does not meet the preset release condition, obtain the current speed of the vehicle; Based on the current speed and a preset mapping relation table, determine the target coasting energy recovery torque of the vehicle to control the vehicle to perform coasting energy recovery based on the target coasting energy recovery torque.

4. The method according to claim 3, wherein Before determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping relation table, it further includes: Use a test bench to perform coasting resistance tests and energy recovery tests; Group the test data according to vehicle speed, and based on the coasting resistance test results and the energy recovery test results, determine the torque value with the largest increase in motor recovery torque and the smoothest deceleration in each test data group as the base torque matching each test data group; Obtain the preset mapping relation table based on each test data group and the base torque matching each test data group.

5. The method according to claim 3, characterized in that, When determining the target coasting energy recovery torque of the vehicle based on the current speed and the preset mapping relation table, it further includes: Obtain the current battery SOC, current battery temperature, current wheel speed difference, and current acceleration of the vehicle; Perform a moving average filtering process on the current battery SOC and the current battery temperature to obtain processed battery state data, and perform a Kalman filtering process on the current wheel speed difference and the current acceleration to obtain processed road condition data; Based on the processed road surface condition data, the extreme value search algorithm is used to determine the road surface friction coefficient, and based on the processed battery state data and the road surface friction coefficient, the PID strategy is used to adjust the target coasting energy recovery torque to obtain a new target coasting energy recovery torque.

6. A braking linkage coasting energy recovery device, characterized in that, It includes: A first judgment module, configured to judge whether a brake pedal displacement signal is detected; An acquisition module, configured to, when the brake pedal displacement signal is detected, based on the brake pedal displacement signal, acquire the displacement speed of the brake pedal and the rebound speed of the brake pedal; A second judgment module, configured to judge whether the brake pedal meets a preset release condition according to the displacement speed of the brake pedal and the rebound speed of the brake pedal; A control module, configured to, when the brake pedal meets the preset release condition, perform filtering processing on the brake pedal displacement signal, and based on the processed brake pedal displacement signal, control the current coasting energy recovery torque of the vehicle to perform coasting energy recovery according to a preset torque condition.

7. The device according to claim 6, characterized in that, The second judgment module is specifically configured to: Judge whether the displacement speed of the brake pedal is greater than or equal to a first preset threshold, and judge whether the rebound speed of the brake pedal is greater than or equal to a second preset threshold; When the displacement speed of the brake pedal is greater than or equal to the first preset threshold and the rebound speed of the brake pedal is greater than or equal to the second preset threshold, acquire the interval duration between the moment when the displacement speed of the brake pedal is equal to the first preset threshold and the moment when the rebound speed of the brake pedal is equal to the second preset threshold; Judge whether the interval duration is less than a preset duration; If the interval duration is less than the preset duration, it is determined that the brake pedal meets the preset release condition, otherwise it is determined that the brake pedal does not meet the preset release condition.

8. The device according to claim 6, characterized in that After judging whether the brake pedal meets the preset release condition, the control module further includes: An acquisition unit, configured to acquire the current speed of the vehicle under the condition that the brake pedal does not meet the preset release condition; A determination unit, configured to determine the target coasting energy recovery torque of the vehicle based on the current speed and a preset mapping table, so as to control the vehicle to perform coasting energy recovery based on the target coasting energy recovery torque.

9. A vehicle, characterized in that, It includes: A memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the program to implement the braking linkage coasting energy recovery method according to any one of claims 1-5.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, The program is executed by the processor to be used to implement the braking linkage coasting energy recovery method according to any one of claims 1-5.

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