Energy recovery method, device and equipment for vehicle

Abstract

An embodiment of the present application provides a vehicle energy recovery method, device and equipment, the method comprising: determining the current driving state of the vehicle, wherein the driving state includes a deceleration state and a constant speed state; when the driving state is the deceleration state or the constant speed state, obtaining the road condition of the vehicle and the distance between the vehicle and the preceding vehicle; determining the energy recovery deceleration based on the road condition of the vehicle and the distance between the vehicle and the preceding vehicle; determining the energy recovery torque based on the energy recovery deceleration, and controlling the vehicle's motor to generate electricity through the energy recovery torque to complete energy recovery.

Description

Technical Field

[0001] The present application relates to, but is not limited to, the field of vehicle control technology, and in particular to a vehicle energy recovery method, device, and equipment. Background Art

[0002] With the rapid development of China's automobile industry, it has been at the forefront of the world in the new track of new energy vehicles. New energy vehicles have quickly entered thousands of households due to their advantages such as environmental protection and low cost of use, but users' requirements for new energy vehicles are also gradually increasing. Among them, driving range is the one that users are most concerned about. While keeping the cost of using the car unchanged, all car companies use energy recovery to improve driving range. At present, car companies obtain the energy recovery torque based on the energy recovery gear set by the user and the current actual vehicle speed. The motor generates electricity in response to the negative torque request sent by the vehicle control unit (VCU), thereby realizing energy recovery. However, the energy recovery method used in the relevant technology cannot adjust the recovery intensity according to the current driving conditions of the vehicle and the driver's intention, resulting in low energy recovery efficiency and the vehicle driving state not being consistent with the driver's intention, which has become a problem. Summary of the Invention

[0003] In view of this, embodiments of the present application provide a vehicle energy recovery method, device, and apparatus.

[0004] The technical solution of this application is achieved as follows:

[0005] In a first aspect, an embodiment of the present application provides a method for energy recovery of a vehicle, the method comprising: determining a current driving state of the vehicle, wherein the driving state includes a deceleration state and a constant speed state; when the driving state is the deceleration state or the constant speed state, obtaining the road condition of the vehicle and the distance between the vehicle and the vehicle in front; determining an energy recovery deceleration based on the road condition of the vehicle and the distance between the vehicle and the vehicle in front; determining an energy recovery torque based on the energy recovery deceleration, and controlling the vehicle's motor to generate electricity through the energy recovery torque to complete energy recovery.

[0006] In a second aspect, an embodiment of the present application provides an energy recovery device for a vehicle, the device comprising: a first determination module for determining the current driving state of the vehicle, wherein the driving state includes a deceleration state and a constant speed state; a first acquisition module for acquiring the road condition of the vehicle and the distance between the vehicle and the vehicle in front when the driving state is the deceleration state or the constant speed state; a second determination module for determining the energy recovery deceleration based on the road condition of the vehicle and the distance between the vehicle and the vehicle in front; a third determination module for determining the energy recovery torque based on the energy recovery deceleration, and controlling the vehicle's motor to generate electricity through the energy recovery torque to complete energy recovery.

[0007] In a third aspect, an embodiment of the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, and the processor implements the steps in the above method when executing the program.

[0008] In the embodiment of the present application, first, the current driving state of the vehicle is determined, wherein the driving state includes a deceleration state and a constant speed state. Second, when the driving state is the deceleration state or the constant speed state, the road condition of the vehicle and the distance between the vehicle and the preceding vehicle are obtained. Then, based on the road condition of the vehicle and the distance between the vehicle and the preceding vehicle, the energy recovery deceleration is determined. Finally, based on the energy recovery deceleration, the energy recovery torque is determined, and the energy recovery torque is used to control the motor power generation of the vehicle to complete energy recovery. It can be seen that the currently appropriate energy recovery deceleration is comprehensively determined based on the current driving state of the vehicle, the road condition of the vehicle, and the distance between the vehicle and the preceding vehicle. By adaptively adjusting the energy recovery deceleration, the energy recovery efficiency is improved, and the current driving state of the vehicle is made consistent with the driver's intention, thereby achieving energy recovery that is more in line with the driver's intention.

[0009] It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and do not limit the technical solutions of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The drawings herein are incorporated into and constitute a part of the specification. These drawings illustrate embodiments consistent with the present application and, together with the specification, are used to illustrate the technical solutions of the present application.

[0011] Figure 1 A schematic diagram of a process flow for implementing a vehicle energy recovery method provided in an embodiment of the present application;

[0012] Figure 2 A schematic diagram of an implementation flow of a method for determining energy recovery torque provided in an embodiment of the present application;

[0013] Figure 3 A schematic diagram of a process for determining the current mass of a vehicle provided in an embodiment of the present application;

[0014] Figure 4 A schematic diagram of a process for determining the current sliding resistance of a vehicle provided in an embodiment of the present application;

[0015] Figure 5 A schematic diagram of the implementation flow of another vehicle energy recovery method provided in an embodiment of the present application;

[0016] Figure 6 A schematic diagram of the structure of an energy recovery device for a vehicle provided in an embodiment of the present application;

[0017] Figure 7 A hardware entity diagram of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions of this application are further elaborated in detail below with reference to the accompanying drawings and embodiments. The described embodiments should not be regarded as limiting this application. All other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0019] In the following description, reference is made to “some embodiments”, which describes a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0020] The terms "first / second / third" involved are merely used to distinguish similar objects and do not represent a specific ordering of the objects. It is understandable that "first / second / third" can be interchanged with a specific order or sequence where permitted so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application pertains. The terms used herein are for the purpose of describing this application only and are not intended to limit this application.

[0022] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0023] The present application provides a method for energy recovery of a vehicle, referring to Figure 1 , the method may include steps S101 to S104, wherein:

[0024] Step S101 : determining the current driving state of the vehicle, wherein the driving state includes a deceleration state and a constant speed state.

[0025] Here, the vehicle can be a pure electric vehicle (EV), a plug-in hybrid electric vehicle including an extended-range electric vehicle (PHEV) or a non-plug-in hybrid electric vehicle (HEV). The embodiment of the present application does not limit the type of vehicle provided.

[0026] Step S102 , when the driving state is the deceleration state or the constant speed state, obtain the road condition of the vehicle and the distance between the vehicle and the preceding vehicle.

[0027] Here, the preceding vehicle is a vehicle that is located in the direction of travel of the vehicle and will have a certain impact on the travel of the vehicle. The road condition of the vehicle can be obtained through the on-board map, wherein the road condition of the vehicle can be mountain road conditions, urban conditions, high-speed conditions, mountain road downhill conditions, urban flat road conditions, urban downhill conditions, high-speed flat road conditions, high-speed downhill conditions, etc. This application does not limit the type of road condition the vehicle is in. The distance between the vehicle and the preceding vehicle can be obtained through on-board radar, millimeter-wave radar, camera, and lidar. This application does not limit the method of obtaining the distance between the vehicle and the preceding vehicle.

[0028] Step S103 : determining the energy recovery deceleration based on the road condition of the vehicle and the distance between the vehicle and the preceding vehicle.

[0029] Here, since both the road condition and the distance to the preceding vehicle will affect the energy recovery deceleration, the energy recovery deceleration is obtained by combining the road condition and the distance to the preceding vehicle.

[0030] When the road conditions include mountainous, urban, and highway conditions, the slope for each road condition can be determined first. Then, by calibrating the appropriate regenerative deceleration rate for each slope and distance from the preceding vehicle, a two-dimensional regenerative deceleration table can be generated. In some embodiments, the slope can be further refined based on mountainous, urban, and highway conditions. Specifically, the same slope value can correspond to different road conditions, such as a 30-degree mountain slope, a 30-degree urban slope, and a 30-degree highway slope, thereby generating a more refined regenerative deceleration table.

[0031] During implementation, the current appropriate energy recovery deceleration can be determined by querying the energy recovery deceleration table.

[0032] In step S104 , an energy recovery torque is determined based on the energy recovery deceleration, and the motor of the vehicle is controlled to generate electricity by using the energy recovery torque to complete energy recovery.

[0033] Here, when the energy recovery torque is determined, the VCU sends an energy recovery torque request to the vehicle's motor. The motor responds to the energy recovery torque request and generates electricity, charging the electricity generated by the motor into the vehicle's battery pack to complete energy recovery.

[0034] In some embodiments, reference Figure 2 The implementation of “determining the energy recovery torque based on the energy recovery deceleration” in step S104 may include the following steps S211 to S213:

[0035] Step S211: Determine the current mass and current sliding resistance of the vehicle.

[0036] Here, the current mass of the vehicle is the mass of the entire vehicle when the mass of the passengers and cargo on the vehicle is stable, and the current sliding resistance is determined based on the determined current mass of the vehicle and the current speed of the vehicle.

[0037] Step S212: Obtain the slope of the road section where the vehicle is located and the rolling radius of the tire of the vehicle.

[0038] Here, the slope of the road section on which the vehicle is located can be obtained through sensors on the vehicle or an onboard high-precision map. This application does not limit the method of obtaining the slope. For example, the onboard high-precision map can be used to know in advance the slope changes of the road ahead, and the intensity of energy recovery can be adjusted according to the changes in the slope of the road ahead. The rolling radius of the vehicle's tires is determined when the vehicle leaves the factory.

[0039] Step S213: determining the energy recovery torque based on the slope, the tire rolling radius, the energy recovery deceleration, the current mass, and the current sliding resistance.

[0040] Here, the energy recovery torque is calculated using the following formula (1) based on the slope of the road section where the vehicle is located, the tire rolling radius, the energy recovery deceleration, the current mass of the vehicle, and the current sliding resistance.

[0041] T wheel =(m n g*sinθ+m n *a2+f n )*r (1);

[0042] Where: T wheel is the energy recovery torque, Newton-meter (Nm);

[0043] m nis the current mass of the vehicle, in kilograms (kg);

[0044] θ is the slope of the road section where the vehicle is located, °;

[0045] a2 is the energy recovery deceleration, meters per second squared (m / s 2 );

[0046] f n is the current sliding resistance, Newton (N);

[0047] r is the rolling radius of the vehicle's tire, in meters (m).

[0048] In the embodiment of the present application, first, the current driving state of the vehicle is determined, wherein the driving state includes a deceleration state and a constant speed state. Second, when the driving state is the deceleration state or the constant speed state, the road condition of the vehicle and the distance between the vehicle and the preceding vehicle are obtained. Then, based on the road condition of the vehicle and the distance between the vehicle and the preceding vehicle, the energy recovery deceleration is determined. Finally, based on the energy recovery deceleration, the energy recovery torque is determined, and the energy recovery torque is used to control the motor power generation of the vehicle to complete energy recovery. It can be seen that the currently appropriate energy recovery deceleration is comprehensively determined based on the current driving state of the vehicle, the road condition of the vehicle, and the distance between the vehicle and the preceding vehicle. By adaptively adjusting the energy recovery deceleration, the energy recovery efficiency is improved, and the current driving state of the vehicle is made consistent with the driver's intention, thereby achieving energy recovery that is more in line with the driver's intention.

[0049] In some embodiments, reference Figure 3 The implementation of “determining the current mass of the vehicle” in step S211 may include the following steps S311 to S314:

[0050] Step S311: determining the estimated mass of the vehicle at the Nth moment based on the estimated sliding resistance of the vehicle at the N-1th moment, where N is an integer greater than 0.

[0051] In some embodiments, the implementation of step S311 "determining the estimated mass of the vehicle at the Nth moment based on the estimated sliding resistance of the vehicle at the N-1th moment" may include: determining the estimated mass of the vehicle at the Nth moment based on the estimated sliding resistance of the vehicle at the N-1th moment through a first expression based on the principle of mechanical equilibrium.

[0052] Here, the first expression is used to calculate the estimated mass of the vehicle at the Nth moment based on the estimated sliding resistance of the vehicle at the N-1th moment, wherein the first expression is the following formula (2):

[0053]

[0054] Where m1 is the estimated mass of the vehicle at the Nth moment, kg;

[0055] F is the current driving force of the vehicle, N;

[0056] f is the estimated sliding resistance of the vehicle at the N-1th moment, N;

[0057] g is the acceleration due to gravity, g = 9.8 m / s 2 ;

[0058] θ is the slope of the road section where the vehicle is located, °;

[0059] a is the current acceleration of the vehicle, m / s 2 ;

[0060] T is the current wheel end torque of the vehicle, in Newton meters (Nm);

[0061] r is the rolling radius of the vehicle's tire, m.

[0062] Step S312: Determine the estimated sliding resistance of the vehicle at the Nth moment based on the estimated mass at the Nth moment and the acquired real-time speed of the vehicle.

[0063] In some embodiments, the implementation of step S312 "determining the estimated sliding resistance of the vehicle at the Nth moment based on the estimated mass at the Nth moment and the obtained real-time speed of the vehicle" may include: determining the estimated sliding resistance of the vehicle at the Nth moment through a second expression based on the estimated mass at the Nth moment and the obtained real-time speed of the vehicle; wherein the second expression is an expression obtained by calibration with a reference mass and adjusted according to the relationship between the estimated mass at the Nth moment and the reference mass, and is used to characterize the relationship between speed and sliding resistance.

[0064] Here, the second expression is used to calculate the estimated sliding resistance of the vehicle at the Nth moment based on the reference mass, the estimated mass at the Nth moment, the real-time speed of the vehicle, the tire rolling resistance coefficient at the reference mass, and the current tire rolling resistance coefficient. The second expression is the following formula (3):

[0065]

[0066] Where f2 is the estimated sliding resistance of the vehicle at the Nth moment;

[0067] m1 is the estimated mass of the vehicle at the Nth moment;

[0068] Mt is the baseline mass of the vehicle during the test;

[0069] Ti is the tire rolling resistance coefficient at reference mass;

[0070] Ti1 is the current tire rolling resistance coefficient (which can be known by querying the current tire temperature and tire pressure table).

[0071] The coefficients a, b, and c in formula (3) are obtained by calibrating the reference mass at different speeds. However, since the reference mass is different from the current mass of the vehicle, and the vehicle's current tire pressure, temperature and other parameters are also different, the direct use of f2 = a + b*v + c*v 2 The calculated sliding resistance is not accurate. However, the relationship between vehicle speed and sliding resistance remains constant under different mass or parameter conditions. Therefore, only the constant term a needs to be adjusted to obtain an accurate expression for calculating sliding resistance.

[0072] and It is the adjustment amount of the constant term a, which is used to express the change in the tire rolling resistance. It has a certain proportional relationship with the reference mass. The rolling resistance coefficient is obtained by looking up parameters such as tire pressure and temperature. The influence of factors such as tire pressure and temperature is also taken into account, so that the sliding resistance can be obtained more accurately.

[0073] Step S313 : determining the estimated mass of the vehicle at the N+1th moment based on the estimated coasting resistance of the vehicle at the Nth moment.

[0074] Here, based on the estimated sliding resistance of the vehicle at the Nth moment, the estimated mass of the vehicle at the N+1th moment is calculated using the above formula (2).

[0075] Step S314 : When the difference between the estimated mass at the N+1th moment and the estimated mass at the Nth moment is within a preset range, the estimated mass at the N+1th moment is determined as the current mass of the vehicle.

[0076] Here, if the estimated mass at time N+1 differs from the estimated mass at time N by more than a preset range, the estimated coasting resistance of the vehicle at time N is adjusted through a loop iterative calculation, thereby adjusting the estimated mass at time N+1. If the estimated mass at time N+1 differs from the estimated mass at time N by within a preset range, the estimated mass at time N+1 is determined to be the current mass of the vehicle.

[0077] Because the estimated vehicle mass is derived from an expression based on the principle of mechanical equilibrium, the result is relatively accurate, and the change in sliding resistance should be very small over a short period of time. When the estimated masses obtained from two consecutive calculations are very close, it means that the sliding resistance has been calculated relatively accurately. At this time, formula (2) has been adjusted to the expression of sliding resistance under the current mass.

[0078] In some embodiments, reference Figure 4 The implementation of “determining the current sliding resistance of the vehicle” in step S211 may include the following steps S411 to S413:

[0079] Step S411: Determine a third expression based on the current mass of the vehicle and the second expression, wherein the third expression is obtained by calibration with a reference mass and adjusted by the relationship between the current mass and the reference mass, and is an expression for characterizing the relationship between speed and sliding resistance.

[0080] Here, the third expression is used to calculate the sliding resistance of the vehicle based on the reference mass, the current mass of the vehicle, the real-time speed of the vehicle, the tire rolling resistance coefficient at the reference mass, and the current tire rolling resistance coefficient. The third expression is the following formula (4):

[0081]

[0082] Where m is the current mass of the vehicle; f3 is the current sliding resistance of the vehicle.

[0083] The third expression is an expression for calculating the sliding resistance under the current mass of the vehicle obtained through the adjustment of the above steps S311 to S314.

[0084] Step S412: Acquire the real-time speed of the vehicle.

[0085] Step S413: determining the current sliding resistance of the vehicle through the third expression based on the current mass of the vehicle and the real-time speed of the vehicle.

[0086] Here, the current mass of the vehicle is a relatively accurate value, so the current sliding resistance of the vehicle obtained by formula (4) is also a relatively accurate value.

[0087] In some embodiments, determining the estimated sliding resistance at the first moment includes the following steps S511 and S512:

[0088] Step S511, obtaining the speed of the vehicle at the first moment;

[0089] Here, the speed at the first moment can be the speed when the driver gets on the vehicle and restarts the vehicle after opening and closing the doors and tailgate. It can also be any moment when the current mass of the vehicle is determined.

[0090] Step S512: Based on the speed at the first moment, determine the estimated sliding resistance at the first moment through a fourth expression, wherein the fourth expression is an expression obtained through the reference mass calibration and is used to characterize the relationship between speed and sliding resistance.

[0091] Here, the fourth expression is the following formula (5):

[0092] f1=a+b*v+c*v 2 (5)

[0093] Where f1 is the estimated sliding resistance at the first moment; a, b, and c are determined by the expression used to characterize the relationship between speed and sliding resistance obtained through reference mass calibration.

[0094] In some embodiments, since the fourth expression is used to determine the estimated gliding resistance at the first moment, and through the iterative process of estimating the mass from step S311 to step S314, even if the estimated gliding resistance at the first moment is inaccurate, it will be corrected during the iterative process, so the fourth expression can also be any preset value.

[0095] In some embodiments, the implementation of the “method for determining the fourth expression” in step S512 may include the following steps S611 to S613:

[0096] Step S611 : determining the sliding resistance corresponding to different preset speeds under the reference mass.

[0097] Here, different preset speeds are speeds pre-set during the test process. During the vehicle driving process, different preset speeds correspond to different sliding resistances.

[0098] Step S612: determining a glide curve between the preset speed and the glide resistance based on the preset speed and the glide resistance corresponding to the preset speed.

[0099] Here, the sliding curve is obtained by fitting the preset speed and sliding resistance.

[0100] Step S613: Determine the fourth expression based on the gliding curve.

[0101] Here, a, b, and c can be determined by the sliding curve, thereby determining the fourth expression.

[0102] In some embodiments, the implementation of step S102 "obtaining the road condition of the vehicle and the distance between the vehicle and the preceding vehicle when the driving state is the deceleration state or the constant speed state" may include the following steps S111 and S112:

[0103] Step S111 : when the driving state is the deceleration state or the constant speed state, obtaining the current speed of the vehicle.

[0104] Here, the current speed of the vehicle is the real-time speed of the vehicle when the vehicle is in a deceleration state or a constant speed state.

[0105] Step S112: When the current speed of the vehicle is greater than a preset speed, the road condition of the vehicle and the distance between the vehicle and the preceding vehicle are obtained.

[0106] Here, the preset speed refers to a speed at which energy recovery is not required. For example, the preset speed may be 8 kilometers per hour (km / h). If the vehicle's current speed is less than the preset speed, energy recovery is not required due to the low speed. If the vehicle's current speed is greater than or equal to the preset speed, the vehicle's road conditions can be obtained through the onboard map, and the onboard radar can be used to determine the distance between the vehicle and the preceding vehicle, thereby executing steps S103 to S104.

[0107] The embodiment of the present application calculates the current vehicle mass (curb mass + mass of passengers and cargo) through information such as wheel-end torque, acceleration, and slope, and calculates the vehicle's current sliding resistance based on the vehicle's current mass, baseline mass, the rolling resistance coefficient of the vehicle's tires at the baseline mass, and the current tire rolling resistance coefficient. Then, based on the high-precision map, the current road conditions and the radar's judgment of the distance between the vehicle and surrounding vehicles, the current appropriate energy recovery intensity is comprehensively judged. By adaptively adjusting the energy recovery strength, the problems of low energy recovery efficiency and the vehicle's driving state not being consistent with the driver's intention are solved, thereby achieving energy recovery that is more in line with the driver's intention and improving energy recovery efficiency. The implementation of energy recovery includes the following steps:

[0108] Step 11, calculate the current mass of the vehicle.

[0109] Each time the vehicle is restarted after opening and closing the door and tailgate, the current mass m of the vehicle is calculated using formula (6) based on information such as motor torque, vehicle speed, slope, acceleration, etc., where formula (6) is as follows:

[0110]

[0111] Where: m is the current mass of the vehicle, kg;

[0112] F is the current driving force of the vehicle, N;

[0113] f is the sliding resistance (including rolling resistance, wind resistance, transmission resistance, etc.) of the vehicle, N;

[0114] g is the acceleration due to gravity, g = 9.8 m / s 2 ;

[0115] θ is the current slope of the vehicle (i.e., the slope of the road section where the vehicle is located), °;

[0116] a is the current acceleration of the vehicle, m / s 2 ;

[0117] T is the current wheel end torque of the vehicle, Nm;

[0118] r is the rolling radius of the vehicle's tire, m;

[0119] a, b, and c are the basic sliding resistance coefficients of the vehicle; a is a constant term, b is the linear coefficient, and c is the quadratic coefficient. These data are obtained from actual vehicle measurements.

[0120] v is the current speed of the vehicle (i.e. the real-time speed of the above vehicle), km / h.

[0121] Step 12: Fit the current sliding resistance.

[0122] During the actual vehicle testing process, the vehicle's test mass (i.e., the aforementioned reference mass) Mt and the sliding resistance under the test mass f1 = a + b*v + c*v are obtained. 2 and the tire rolling resistance coefficient Ti. Based on the current tire temperature and tire pressure, the current tire rolling resistance coefficient Ti1 is obtained by looking up a table (the table is obtained through tire bench testing). Based on the estimated vehicle mass m1 obtained in step 11, the current sliding resistance f2 is calculated using formula (3), where formula (7) is as follows:

[0123]

[0124] Step 13: Calculate the current sliding resistance.

[0125] Substitute the current sliding resistance f2 obtained in step 12 into formula (6) in step 11 to calculate the new estimated mass. Iterate steps 11 and 12 until the estimated mass of the vehicle in this round is within 1% of the estimated mass of the vehicle in the previous round. Then, stop iterating. Set the estimated mass of the vehicle in the last round as the current mass of the vehicle. Substitute the current mass of the vehicle into formula (7) in step 12 to calculate the current sliding resistance.

[0126] Step 14: Calculate the required wheel end torque (ie, the energy recovery torque mentioned above).

[0127] After obtaining the vehicle's current mass and sliding resistance in steps 11 to 13, the vehicle's current road condition (e.g., mountain road condition, urban condition, highway condition, etc.) is determined based on the onboard map information. The distance between the current vehicle and the preceding vehicle is then determined based on the onboard radar information. The vehicle's current road condition and the distance between the current vehicle and the preceding vehicle are summarized and sent to the VCU. The VCU then provides the current appropriate target deceleration (i.e., the energy recovery deceleration described above) a2 based on a strategy table containing information such as the vehicle's current road condition and the distance between the current vehicle and the preceding vehicle. The required wheel-end torque T is calculated using formula (8): wheel The vehicle's motor generates electricity in response to the VCU torque request, and charges the electricity generated by the motor into the battery pack, thereby achieving adaptive energy recovery.

[0128] T wheel =(m n g*sinθ+m n *a2+f n )*r (8)

[0129] Where: T wheel is the target wheel end torque for energy recovery, Nm;

[0130] m n is the final vehicle current mass obtained in step 3, kg;

[0131] θ is the current slope of the vehicle, °;

[0132] a2 is the current target deceleration, m / s 2 ;

[0133] f n is the sliding resistance of the current vehicle obtained in step 3, N;

[0134] r is the rolling radius of the vehicle's tire, m.

[0135] For example, when the vehicle is currently traveling downhill on a mountain road, the gradient measured by the vehicle's sensors is used to calculate the regenerative torque required to maintain the current speed. This prevents the regenerative torque from being too weak, causing the vehicle to slide faster and faster, requiring the driver to brake to slow down. On flat, downhill roads in urban areas, the regenerative deceleration rate is adaptively adjusted to avoid excessive regenerative deceleration, which would shorten the coasting distance and require the driver to periodically apply the accelerator to increase speed. When following a vehicle on highways or in urban areas, the regenerative intensity is adjusted based on the distance between the current vehicle and the preceding vehicle, as measured by radar. For example, when the distance between the current vehicle and the preceding vehicle is large, the regenerative intensity is reduced, allowing the vehicle to coast further; when the distance between the current vehicle and the preceding vehicle is small, the regenerative intensity is increased, maintaining a safe distance between the two vehicles.

[0136] The following is an example of a specific scenario. Figure 5 The following describes the overall process of implementing another vehicle energy recovery method provided by an embodiment of the present application. Figure 5 , the method comprises the following steps:

[0137] Step 501, estimating the current vehicle mass (curb mass + passenger mass + cargo mass) based on signals such as motor torque, vehicle speed, slope, and acceleration;

[0138] Step 502: fitting the current sliding resistance according to the estimated mass, tire temperature, and tire pressure;

[0139] If N=1 or the difference between the two estimated qualities (i.e., the estimated quality at the N+1th moment and the estimated quality at the Nth moment) is greater than 1%, then execute steps 501 and 502 in sequence; if N≥2 and the difference between the two estimated qualities is less than or equal to 1%, then execute step 503;

[0140] Step 503: The vehicle-mounted high-precision map provides the vehicle's current operating conditions (i.e., the road conditions the vehicle is on): mountain road downhill, city flat road, city downhill, highway flat road, highway downhill;

[0141] In step 504, the vehicle radar provides the distance between the surrounding vehicles (i.e., the distance between the aforementioned vehicle and the preceding vehicle). If the preceding vehicle is close, the recovery intensity can be increased and the vehicle speed can be quickly reduced; if the preceding vehicle is far away, the recovery intensity can be reduced and the coasting distance can be increased.

[0142] Step 505: The VCU determines an appropriate target deceleration (i.e., the energy recovery deceleration) based on the vehicle's operating conditions, the distance to surrounding vehicles, and other information.

[0143] In step 506 , the required torque at the wheel end (i.e., the energy recovery torque) is calculated based on the target deceleration, slope, coasting resistance, vehicle mass (i.e., the current mass of the vehicle), and the motor generates electricity in response to the torque request to complete energy recovery.

[0144] Compared with the prior art, this application has the following advantages:

[0145] 1. Adaptively adjust the energy recovery intensity based on information such as vehicle mass, driving conditions, and the distance between the current vehicle and the vehicle in front, so that the vehicle's driving state is more in line with the driver's intention while improving energy recovery efficiency.

[0146] 2. Use important parameters such as the vehicle's current weight, tire rolling resistance, sliding resistance, and road slope as prerequisites for adjusting energy recovery intensity.

[0147] 3. Use the vehicle’s high-precision map to obtain the vehicle’s current driving conditions as a condition for adjusting the energy recovery intensity.

[0148] 4. The distance between the current vehicle and the preceding vehicle obtained by the radar is used as a condition for adjusting the energy recovery intensity.

[0149] Based on the foregoing embodiments, an embodiment of the present application provides an energy recovery device for a vehicle, which includes the modules included, the sub-modules included in each module, the units included in each sub-module, and the sub-units included in each unit, and can be implemented by a processor in a computer device; of course, it can also be implemented by a specific logic circuit; in the implementation process, the processor can be a central processing unit (CPU), a microprocessor (MPU), a digital signal processor (DSP) or a field programmable gate array (FPGA), etc.

[0150] Figure 3 A schematic diagram of the structure of an energy recovery device for a vehicle provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, the energy recovery device 600 of the vehicle includes: a first determination module 610, a first acquisition module 620, a second determination module 630 and a third determination module 640, wherein:

[0151] A first determining module 610 is configured to determine a current driving state of the vehicle, wherein the driving state includes a deceleration state and a constant speed state;

[0152] A first acquisition module 620 is configured to acquire the road condition of the vehicle and the distance between the vehicle and a preceding vehicle when the driving state is the deceleration state or the constant speed state;

[0153] A second determining module 630 is configured to determine an energy recovery deceleration based on a road condition of the vehicle and a distance between the vehicle and a preceding vehicle;

[0154] The third determination module 640 is configured to determine the energy recovery torque based on the energy recovery deceleration, and control the motor of the vehicle to generate electricity through the energy recovery torque to complete energy recovery.

[0155] In some embodiments, the third determination module 640 includes: a first determination submodule, used to determine the current mass and current sliding resistance of the vehicle; a first acquisition submodule, used to obtain the slope of the road section on which the vehicle is located and the tire rolling radius of the vehicle; and a second determination submodule, used to determine the energy recovery torque based on the slope, the tire rolling radius, the energy recovery deceleration, the current mass and the current sliding resistance.

[0156] In some embodiments, the first determination submodule includes: a first determination unit, used to determine the estimated mass of the vehicle at the Nth moment based on the estimated sliding resistance of the vehicle at the N-1th moment, where N is an integer greater than 0; a second determination unit, used to determine the estimated sliding resistance of the vehicle at the Nth moment based on the estimated mass at the Nth moment and the acquired real-time speed of the vehicle; a third determination unit, used to determine the estimated mass of the vehicle at the N+1th moment based on the estimated sliding resistance of the vehicle at the Nth moment; and a fourth determination unit, used to determine the estimated mass at the N+1th moment as the current mass of the vehicle when the estimated mass at the N+1th moment differs from the estimated mass at the Nth moment within a preset range.

[0157] In some embodiments, the first determination unit is further used to determine the estimated mass of the vehicle at the Nth moment through a first expression based on the principle of mechanical equilibrium based on the estimated sliding resistance of the vehicle at the N-1th moment; the second determination unit is further used to determine the estimated sliding resistance of the vehicle at the Nth moment through a second expression based on the estimated mass at the Nth moment and the acquired real-time speed of the vehicle; wherein the second expression is obtained through benchmark mass calibration and adjusted through the relationship between the estimated mass at the Nth moment and the benchmark mass, and is an expression for characterizing the relationship between speed and sliding resistance.

[0158] In some embodiments, the first determination submodule includes: a fifth determination unit, used to determine a third expression based on the current mass of the vehicle and the second expression, wherein the third expression is obtained by calibration of the reference mass and adjustment by the relationship between the current mass and the reference mass, and is used to characterize the relationship between speed and sliding resistance; a first acquisition unit, used to obtain the real-time speed of the vehicle; and a sixth determination unit, used to determine the current sliding resistance of the vehicle through the third expression based on the current mass of the vehicle and the real-time speed of the vehicle.

[0159] In some embodiments, the vehicle's energy recovery device 600 further includes: a second acquisition module for acquiring the speed of the vehicle at the first moment; and a fourth determination module for determining the estimated sliding resistance at the first moment through a fourth expression based on the speed at the first moment, wherein the fourth expression is an expression obtained through the reference mass calibration for characterizing the relationship between speed and sliding resistance.

[0160] In some embodiments, the vehicle's energy recovery device 600 also includes: a fifth determination module for determining the sliding resistance corresponding to different preset speeds under the reference mass; a sixth determination module for determining a sliding curve between the preset speed and the sliding resistance based on the preset speed and the sliding resistance corresponding to the preset speed; and a seventh determination module for determining the fourth expression based on the sliding curve.

[0161] In some embodiments, the first acquisition module includes: a first acquisition sub-module, used to obtain the current speed of the vehicle when the driving state is the deceleration state or the constant speed state; a second acquisition sub-module, used to obtain the road condition of the vehicle and the distance between the vehicle and the vehicle in front when the current speed of the vehicle is greater than the preset speed.

[0162] The description of the above device embodiment is similar to the description of the above method embodiment and has similar beneficial effects as the method embodiment. In some embodiments, the functions or modules included in the device provided in the embodiments of the present application can be used to perform the methods described in the above method embodiments. For technical details not disclosed in the device embodiments of the present application, please refer to the description of the method embodiments of the present application for understanding.

[0163] It should be noted that, in the embodiment of the present application, if the above-mentioned vehicle energy recovery method is implemented in the form of a software function module and is sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the embodiment of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a software product, which is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as a U disk, a mobile hard disk, a read-only memory (ROM), a magnetic disk or an optical disk. In this way, the embodiment of the present application is not limited to any specific hardware, software or firmware, or any combination of hardware, software and firmware.

[0164] An embodiment of the present application also provides a computer device, including a memory and a processor of a server or a memory and a processor of a user terminal, wherein the memory stores a computer program that can be run on the processor, and when the processor executes the program, some or all of the steps in the above method are implemented.

[0165] The present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements some or all of the steps in the above method. The computer-readable storage medium may be transient or non-transient.

[0166] An embodiment of the present application also provides a computer program, including computer-readable code. When the computer-readable code runs in a server or a user terminal, the processor in the server or the user terminal executes some or all of the steps for implementing the above method.

[0167] The present application also provides a computer program product, which includes a non-transitory computer-readable storage medium storing a computer program, and when the computer program is read and executed by a computer, implements some or all of the steps in the above method. The computer program product can be implemented specifically by hardware, software, or a combination thereof. In some embodiments, the computer program product is embodied as a computer storage medium. In other embodiments, the computer program product is embodied as a software product, such as a software development kit (SDK).

[0168] It should be noted that the descriptions of the various embodiments above tend to emphasize the differences between the various embodiments, and their similarities or similarities can be referenced to each other. The descriptions of the above device, storage medium, computer program, and computer program product embodiments are similar to the descriptions of the above method embodiments and have similar beneficial effects as the method embodiments. For technical details not disclosed in the embodiments of the device, storage medium, computer program, and computer program product of this application, please refer to the description of the method embodiments of this application for understanding.

[0169] It should be noted that Figure 7 A schematic diagram of a hardware entity of a computer device in an embodiment of the present application is shown in FIG. Figure 7 As shown, the hardware entity of the computer device 700 includes: a processor 701, a communication interface 702 and a memory 703, wherein:

[0170] Processor 701 generally controls the overall operation of computer device 700 .

[0171] The communication interface 702 enables the computer device to communicate with other terminals or servers through a network.

[0172] The memory 703 is configured to store instructions and applications executable by the processor 701. It can also cache data to be processed or processed by the processor 701 and various modules in the computer device 700 (for example, image data, audio data, voice communication data, and video communication data). This can be implemented using flash memory (FLASH) or random access memory (RAM). Data can be transmitted between the processor 701, the communication interface 702, and the memory 703 via a bus 704.

[0173] It should be understood that "one embodiment" or "an embodiment" mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification does not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned steps / processes does not mean the order of execution, and the execution order of each step / process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application. The above-mentioned serial numbers of the embodiments of the present application are for description only and do not represent the advantages and disadvantages of the embodiments.

[0174] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0175] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as: multiple units or components can be combined, or can be integrated into another system, or some features can be ignored or not executed. In addition, the coupling, direct coupling, or communication connection between the components shown or discussed can be through some interfaces, and the indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0176] The units described above as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units; they may be located in one place or distributed across multiple network units; some or all of the units may be selected according to actual needs to achieve the purpose of the scheme of this embodiment.

[0177] In addition, all functional units in the embodiments of the present application can be integrated into one processing unit, or each unit can be a separate unit, or two or more units can be integrated into one unit; the above-mentioned integrated units can be implemented in the form of hardware or in the form of hardware plus software functional units.

[0178] Those skilled in the art will understand that all or part of the steps of implementing the above-mentioned method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above-mentioned method embodiment; and the aforementioned storage medium includes: mobile storage devices, read-only memories (ROM), magnetic disks or optical disks, and other media that can store program codes.

[0179] Alternatively, if the above-mentioned integrated unit of the present application is implemented in the form of a software function module and sold or used as an independent product, it can also be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the relevant technology, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the methods described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as mobile storage devices, ROMs, magnetic disks, or optical disks.

[0180] The above is only an implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

Claims

1. A vehicle energy recovery method, characterized in that: The method comprises: Determining a current driving state of the vehicle, wherein the driving state includes a deceleration state and a constant speed state; When the driving state is the deceleration state or the constant speed state, obtaining the road condition of the vehicle and the distance between the vehicle and the preceding vehicle; determining an energy recovery deceleration based on a road condition of the vehicle and a distance between the vehicle and a preceding vehicle; determining an estimated mass of the vehicle at time N based on the estimated coasting resistance of the vehicle at time N-1, where N is an integer greater than 0; determining an estimated sliding resistance of the vehicle at the Nth moment based on the estimated mass at the Nth moment and the acquired real-time speed of the vehicle; determining an estimated mass of the vehicle at time (N+1) based on the estimated coasting resistance of the vehicle at time (N); If the estimated mass at the N+1th moment differs from the estimated mass at the Nth moment within a preset range, determining the estimated mass at the N+1th moment as the current mass of the vehicle; Determine the current sliding resistance; Obtaining the slope of the road section on which the vehicle is located and the rolling radius of the tire of the vehicle; Based on the slope, the tire rolling radius, the energy recovery deceleration, the current mass of the vehicle and the current sliding resistance, an energy recovery torque is determined, and the vehicle's motor is controlled to generate electricity through the energy recovery torque to complete energy recovery; wherein, the current sliding resistance is determined based on the current mass of the vehicle and the current speed of the vehicle.

2. The method according to claim 1, characterized in that Determining the estimated mass of the vehicle at time N based on the estimated coasting resistance of the vehicle at time N-1 includes: determining a first difference between a current driving force on the vehicle and an estimated coasting resistance of the vehicle at time (N-1), and determining the first difference as a first result; Determining a first product of the acceleration due to gravity and the sine value of the slope of the road section on which the vehicle is located, and determining the sum of the first product and the current acceleration of the vehicle as a second result; Determining the quotient of the first result and the second result as the estimated mass of the vehicle at the Nth moment; Determining the estimated sliding resistance of the vehicle at the Nth moment based on the estimated mass at the Nth moment and the acquired real-time speed of the vehicle includes: determining a second difference between the tire rolling resistance coefficient at the reference mass and the current tire rolling resistance coefficient, and determining a quotient of the second difference and 1000 as a third result; determining a ratio of the estimated mass of the vehicle at the Nth moment to the reference mass of the vehicle during the test as a fourth result; determining a first adjustment amount by multiplying a baseline mass of the vehicle during the test, the gravitational acceleration, the third result, and the fourth result; determining a third difference between the first coefficient and the first adjustment amount; determining a third product of the second coefficient and the real-time speed of the vehicle; determining the sum of the third difference, the third product, the product of the third coefficient and the square of the real-time speed of the vehicle as the estimated coasting resistance of the vehicle at the Nth moment; The first coefficient, the second coefficient, and the third coefficient are obtained by calibrating a reference mass at different speeds.

3. The method according to claim 2, characterized in that Determining a current coasting resistance of the vehicle, comprising: determining a ratio of the current mass of the vehicle to a reference mass of the vehicle during the test as a fifth result; determining a second adjustment amount by multiplying the vehicle's baseline mass, gravitational acceleration, the third result, and the fifth result during the test; determining a fourth difference between the first coefficient and the second adjustment amount; determining a fourth product of the second coefficient and the real-time speed of the vehicle; The sum of the fourth difference, the fourth product, and the product of the third coefficient and the square of the real-time speed of the vehicle is determined as the current sliding resistance of the vehicle.

4. The method according to claim 2, characterized in that Determine the estimated sliding resistance at moment 1, including: Obtaining the speed of the vehicle at the first moment; Based on the speed at the first moment, the estimated sliding resistance at the first moment is determined by a fourth expression, wherein the fourth expression is an expression obtained by the reference mass calibration and is used to characterize the relationship between speed and sliding resistance.

5. The method according to claim 4, characterized in that The method for determining the fourth expression includes: determining the sliding resistance corresponding to different preset speeds at the reference mass; determining a sliding curve between the preset speed and the sliding resistance based on the preset speed and the sliding resistance corresponding to the preset speed; Based on the coasting curve, the fourth expression is determined.

6. The method according to any one of claims 1 to 3, characterized in that When the driving state is the deceleration state or the constant speed state, obtaining the road condition of the vehicle and the distance between the vehicle and the preceding vehicle includes: When the driving state is the deceleration state or the constant speed state, obtaining the current speed of the vehicle; When the current speed of the vehicle is greater than a preset speed, the road condition of the vehicle and the distance between the vehicle and the preceding vehicle are obtained.

7. An energy recovery device for a vehicle, characterized in that: The device comprises: A first determining module is configured to determine a current driving state of the vehicle, wherein the driving state includes a deceleration state and a constant speed state; a first acquisition module, configured to acquire, when the driving state is the deceleration state or the constant speed state, the road condition of the vehicle and the distance between the vehicle and a preceding vehicle; a second determining module, configured to determine an energy recovery deceleration based on a road condition of the vehicle and a distance between the vehicle and a preceding vehicle; a third determination module configured to determine an estimated mass of the vehicle at moment N based on the estimated coasting resistance of the vehicle at moment N-1, where N is an integer greater than 0; determine the estimated coasting resistance of the vehicle at moment N based on the estimated mass at moment N and the acquired real-time speed of the vehicle; determine the estimated mass of the vehicle at moment N+1 based on the estimated coasting resistance of the vehicle at moment N; if the estimated mass at moment N+1 differs from the estimated mass at moment N within a preset range, determine the estimated mass at moment N+1 as the current mass of the vehicle; determine the current coasting resistance; acquire the slope of a road section on which the vehicle is located and a rolling radius of a tire of the vehicle; determine a regenerative torque based on the slope, the rolling radius of the tire, the regenerative deceleration, the current mass of the vehicle, and the current coasting resistance, and control the motor of the vehicle to generate electricity using the regenerative torque to achieve energy recovery; wherein the current coasting resistance is determined based on the current mass of the vehicle and the current speed of the vehicle.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program that can be run on the processor, characterized in that: When the processor executes the program, the steps in the method according to any one of claims 1 to 6 are implemented.

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