Vehicle gear control method and device, controller and vehicle

Abstract

The invention relates to a vehicle gear control method and device, a controller and a vehicle, and the method comprises the steps that when it is determined that the vehicle has a gear shifting demand, the maximum sustainable torque of the vehicle at the target vehicle speed and the corrected resistance of the vehicle at the current vehicle speed are determined, the target vehicle speed is the vehicle speed of the vehicle after gear shifting, and the corrected resistance of the vehicle at the current vehicle speed is obtained; the corrected resistance is obtained according to the shaft resistance of a gearbox in the vehicle; according to the maximum sustainable torque and the corrected resistance, candidate gears are determined; determining a target gear in the candidate gears according to the driving requirement of the vehicle; and controlling the vehicle to switch the current gear to the target gear. Compared with the prior art that the gear of the vehicle is controlled according to the rotating speed of the motor of the vehicle, the gear shifting frequency of the vehicle in the gear shifting process can be reduced, the situation of frequent gear shifting of the vehicle can be reduced, then oil consumption of vehicle running can be reduced, the gear shifting duration of the vehicle can be shortened, and then the stability of vehicle running can be guaranteed.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of data processing, in particular, to a vehicle gear control method and device, a controller and a vehicle. BACKGROUND

[0002] The vehicle gear is mainly used for controlling the power output of the engine in the vehicle and the driving speed of the vehicle. In the related art, the gear of the vehicle is controlled according to the motor speed of the vehicle. However, when the gear of the vehicle is controlled by the method in the related art, the vehicle may frequently shift gears, and thus the fuel consumption of the vehicle driving is high, the gear shifting time is too long, and the gear shifting is unstable. SUMMARY

[0003] The purpose of the present disclosure is to provide a vehicle gear control method, device, controller and vehicle to solve the technical problems existing in the related art.

[0004] To achieve the above purpose, in a first aspect, the present disclosure provides a vehicle gear control method, comprising: When it is determined that the vehicle has a gear shifting demand, determining the maximum sustainable torque of the vehicle at a target vehicle speed and a corrected resistance of the vehicle at a current vehicle speed, wherein the target vehicle speed is the vehicle speed of the vehicle after gear shifting, and the corrected resistance is obtained according to the shaft resistance of the gearbox in the vehicle; According to the maximum sustainable torque and the corrected resistance, determining a candidate gear; According to the driving demand of the vehicle, determining a target gear in the candidate gear; Controlling the vehicle to switch the current gear to the target gear.

[0005] Optionally, the step of determining the candidate gear according to the maximum sustainable torque and the corrected resistance comprises: In all gears of the vehicle, determining a first gear greater than or equal to a first threshold value, wherein the first threshold value is obtained by dividing the corrected resistance by the maximum sustainable torque; When the first gear has a second gear, determining the second gear as the candidate gear, wherein the second gear is the gear existing in the vehicle; When the first gear does not have the second gear, and the vehicle speed and / or the slope information of the road changes, re-executing the steps of determining the new maximum sustainable torque and the new corrected resistance of the vehicle, and determining a new first gear greater than or equal to the first threshold value according to the new maximum sustainable torque and the new corrected resistance, and when the new first gear has a new second gear, determining the new second gear as the candidate gear.

[0006] Optionally, the determining the target gear position from the candidate gear positions according to the driving requirement of the vehicle comprises: when the driving requirement of the vehicle is such that the gear ratio of the vehicle is minimized, determining the minimum candidate gear position from the candidate gear positions as the target gear position; when the driving requirement of the vehicle is such that the power performance of the vehicle is maximized, determining the maximum candidate gear position from the candidate gear positions as the target gear position; when the driving requirement of the vehicle is such that the motor efficiency of the vehicle is maximized, obtaining a motor efficiency value corresponding to each candidate gear position, and determining the candidate gear position corresponding to the highest efficiency value from the plurality of efficiency values as the target gear position.

[0007] Optionally, the method further comprises: determining a resistance value of the vehicle at the current vehicle speed and a maximum sustainable torque of the vehicle at the current vehicle speed; when the maximum sustainable torque of the vehicle at the current vehicle speed is less than a second threshold value, determining that the vehicle has a gear shifting requirement, wherein the second threshold value is obtained by dividing the resistance value of the vehicle at the current vehicle speed by the variable gear position of the vehicle during driving.

[0008] Optionally, the corrected resistance of the vehicle at the current vehicle speed is obtained by: determining a target correction coefficient of the vehicle, a weight, a coasting resistance of the vehicle, and slope information of a road on which the vehicle is located, wherein the target correction coefficient is obtained according to a driving condition of the vehicle; determining the axle resistance of the gearbox of the vehicle according to the current vehicle speed, the weight, the coasting resistance, and the slope information; multiplying the axle resistance of the gearbox by the target correction coefficient to obtain the corrected resistance.

[0009] Optionally, the determining the target correction coefficient of the vehicle comprises: determining a target driving condition on a road on which the vehicle is driven; determining the target correction coefficient according to a preset corresponding relationship between the target driving condition and the correction coefficient, wherein the preset corresponding relationship is a corresponding relationship between a driving condition and a correction coefficient.

[0010] Optionally, the determining the target correction coefficient of the vehicle comprises: determining a plurality of driving routes, wherein each driving route corresponds to a different driving condition; collecting a gear shifting frequency of the vehicle during driving on each driving route; According to a whole vehicle dynamics model, the each driving route, and a shift number corresponding to the each driving route, the target correction coefficient of the vehicle is calculated.

[0011] In a second aspect, the present disclosure provides a vehicle gear control device, comprising a first determining module, a second determining module, a third determining module, and a control module. The first determining module is configured to determine a maximum sustainable torque of the vehicle at a target vehicle speed and a correction resistance of the vehicle at a current vehicle speed when the vehicle has a shift demand, wherein the target vehicle speed is a vehicle speed of the vehicle after a shift, and the correction resistance is obtained according to a shaft resistance of a gearbox in the vehicle. The second determining module is configured to determine the candidate gear according to the maximum sustainable torque and the correction resistance. The third determining module is configured to determine a target gear from the candidate gears according to a driving demand of the vehicle. The control module is configured to control the vehicle to switch a current gear to the target gear.

[0012] Optionally, the second determining module comprises: A fourth determining module is configured to determine a first gear greater than or equal to a first threshold value from all gears of the vehicle, wherein the first threshold value is obtained by dividing the correction resistance by the maximum sustainable torque. A fifth determining module is configured to determine a second gear as a candidate gear when the first gear has the second gear, wherein the second gear is a gear existing in the vehicle. A sixth determining module is configured to re-determine a new maximum sustainable torque and a new correction resistance of the vehicle when the first gear does not have the second gear and a vehicle speed and / or a slope information of a road where the vehicle is located changes, and determine a new first gear greater than or equal to the first threshold value according to the new maximum sustainable torque and the new correction resistance, and determine a new second gear as the candidate gear when the new first gear has the new second gear.

[0013] Optionally, the third determining module is configured to: When the driving demand of the vehicle is to minimize a gear ratio of the vehicle, determine a minimum candidate gear from the candidate gears as the target gear. When the driving demand of the vehicle is to maximize a power performance of the vehicle, determine a maximum candidate gear from the candidate gears as the target gear. When the driving demand of the vehicle is that the motor efficiency of the vehicle is the highest, a motor efficiency value corresponding to each candidate gear is obtained, and a candidate gear corresponding to the highest efficiency value in the plurality of efficiency values is determined as the target gear.

[0014] Optionally, the apparatus further comprises: a seventh determination module configured to determine a resistance value of the vehicle at the current vehicle speed and a maximum sustainable torque of the vehicle at the current vehicle speed; a judgment module configured to determine that the vehicle has a shifting demand when the maximum sustainable torque of the vehicle at the current vehicle speed is less than a second threshold value, wherein the second threshold value is obtained by dividing the resistance value of the vehicle at the current vehicle speed by a gear of the vehicle in the driving process.

[0015] Optionally, the first determination module comprises: an eighth determination module configured to determine a target correction coefficient of the vehicle, a weight, a coasting resistance of the vehicle, and slope information of a road on which the vehicle is located, wherein the target correction coefficient is obtained according to a driving condition of the vehicle; a ninth determination module configured to determine the gearbox shaft resistance of the vehicle according to the current vehicle speed, the weight, the coasting resistance, and the slope information; a first calculation module configured to perform a multiplication operation on the gearbox shaft resistance and the target correction coefficient to obtain the correction resistance.

[0016] Optionally, the eighth determination module comprises: a first sub-determination module configured to determine a target driving condition on a road on which the vehicle is driven; a second sub-determination module configured to determine the target correction coefficient according to the target driving condition and a preset corresponding relationship, wherein the preset corresponding relationship is a corresponding relationship between a driving condition and a correction coefficient.

[0017] Optionally, the eighth determination module comprises: a third sub-determination module configured to determine a plurality of driving routes, wherein each driving route corresponds to a different driving condition; a collection module configured to collect a number of gear shifts in a driving process of the vehicle on each driving route; a second calculation module configured to calculate the target correction coefficient of the vehicle according to a vehicle dynamics model, each driving route, and the number of gear shifts corresponding to each driving route.

[0018] In a third aspect, the present disclosure provides a controller, comprising: a memory having a computer program stored thereon; a processor configured to execute the computer program in the memory to implement the steps of any of the methods provided by the first aspect of the present disclosure.

[0019] In a fourth aspect, the present disclosure provides a vehicle comprising the controller provided by the third aspect of the present disclosure.

[0020] According to the above technical solution, when the vehicle needs to change gears, the candidate gears that the vehicle can change to are determined according to the maximum sustainable torque of the vehicle at the target speed and the corrected resistance of the vehicle at the current speed, and then the target gear is determined from the candidate gears according to the driving demand of the vehicle, so that the vehicle changes from the current gear to the target gear. Compared with the related art in which the gear of the vehicle is controlled according to the motor speed of the vehicle, the number of gear changes of the vehicle during gear changing can be reduced, the situation of frequent gear changing of the vehicle can be reduced, the fuel consumption of the vehicle during driving can be reduced, the gear changing time of the vehicle can be reduced, and the stability of the vehicle during driving can be ensured.

[0021] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0022] The accompanying drawings are included to provide a further understanding of the present disclosure and constitute a part of the specification, which together with the following detailed description, serve to explain the present disclosure. In the drawings: Figure 1 FIG. 1 is a schematic diagram illustrating a vehicle gear control method according to an exemplary embodiment of the present disclosure.

[0023] Figure 2 FIG. 2 is a flowchart illustrating a vehicle gear control method according to an exemplary embodiment of the present disclosure.

[0024] Figure 3 FIG. 3 is a schematic diagram illustrating a vehicle gear control device according to an exemplary embodiment of the present disclosure.

[0025] Figure 4 FIG. 4 is a block diagram of a vehicle according to an exemplary embodiment. DETAILED DESCRIPTION

[0026] The specific embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present disclosure, and are not intended to limit the present disclosure.

[0027] Under the dual challenges of energy revolution and carbon emission pressure, as the vehicle market group tends to be younger, the vehicle needs to have low emission function, and at the same time, the vehicle also needs to have power, comfort and economy and other requirements. AMT (Automated Manual Transmission, mechanical automatic transmission) has become a research hotspot of vehicle enterprises. With the development trend of vehicle electrification in the passenger vehicle industry, the vehicle field also faces multiple challenges, and the research on the shift strategy of vehicle AMT transmission is also increasingly deepened.

[0028] In the related art, when the vehicle needs to change gear, the shift is mainly performed according to fixed motor speed points. Specifically, the vehicle speed n is equally divided by the number of gear positions n of the transmission, and the motor speed interval corresponding to the current gear position of the vehicle is determined according to the current gear position of the vehicle. Then, the best efficiency shift point can be determined according to the motor speed corresponding efficiency relationship, the optimal power shift point can be determined according to the vehicle speed acceleration relationship, the shift line can be formulated according to the corresponding relationship between different pedal opening degrees and shift points, and then the final shift line can be determined according to the driving mode of the vehicle.

[0029] However, the inventors have found that when controlling the gear position of the vehicle by the method in the related art, the shift point is mainly obtained by linear interpolation of discrete data points, but this method makes it impossible to select a new gear position under different driving conditions or different vehicle weights. If the vehicle is directly shifted by this method, it may further cause the vehicle to be not well adapted to driving under the corresponding driving condition. Moreover, when the vehicle is climbing a slope, the motor or engine speed may exceed the shift point speed to shift up, but at this time the power cannot meet the current condition to shift down, resulting in frequent shifting of the vehicle on the slope. Fixed shift point shifting may cause the vehicle to run in an inappropriate gear position, resulting in high fuel consumption, long shift time, unstable shifting and motor over-temperature, etc.

[0030] Therefore, the present disclosure provides a vehicle gear control method, device, controller and vehicle to solve the technical problems existing in the related art.

[0031] As Figure 1 shown, Figure 1 is a schematic diagram illustrating a vehicle gear control method according to an exemplary embodiment of the present disclosure, referring to Figure 1 , comprising: S101: When it is determined that the vehicle has a shift demand, determining the maximum sustainable torque of the vehicle at a target vehicle speed and the corrected resistance of the vehicle at a current vehicle speed, wherein the target vehicle speed is the vehicle speed of the vehicle after shifting, and the corrected resistance is obtained according to the shaft resistance of the transmission in the vehicle; S102: determining a candidate gear position according to the maximum sustainable torque and the corrected resistance; S103: determining a target gear position in the candidate gear positions according to a driving demand of the vehicle; S104: controlling the vehicle to switch a current gear position to the target gear position.

[0032] By the above technical solution, when the vehicle needs to change gear position, the candidate gear position that can be changed by the vehicle is determined according to the maximum sustainable torque of the vehicle at the target speed and the corrected resistance of the vehicle at the current speed, and then the target gear position is determined in the candidate gear positions according to the driving demand of the vehicle, so that the vehicle is changed from the current gear position to the target gear position. Compared with the related art of controlling the gear position of the vehicle according to the motor speed of the vehicle, the number of gear changes of the vehicle during gear changing can be reduced, the situation of frequent gear changing of the vehicle can be reduced, the fuel consumption of the vehicle during driving can be reduced, the gear changing time of the vehicle can be reduced, and the stability of the vehicle during driving can be ensured.

[0033] In order for those skilled in the art to better understand the vehicle gear control method provided by the present disclosure, the above steps are described in detail as follows.

[0034] For example, the maximum sustainable torque can be the highest torque value that the motor can reach when driving at the target speed. The target speed can be the speed at which the user needs the vehicle to travel. When the vehicle has a gear changing demand, the maximum sustainable torque of the vehicle at the target speed and the corrected resistance of the vehicle at the current speed can be determined according to the target speed. The maximum sustainable torque can be expressed by the following calculation formula.

[0035]

[0036] wherein, is the maximum sustainable torque of the vehicle at the target speed, V1 is the target speed of the vehicle, is the power of the current motor of the vehicle, r is the wheel radius, is the current gear position of the vehicle, is the rear axle speed ratio of the vehicle. Wherein, can be obtained according to the current operating state of the vehicle and the power characteristics of the motor.

[0037] In a possible manner, the corrected resistance of the vehicle at the current speed is obtained by the following method: determining a target correction coefficient, a weight, a coasting resistance of the vehicle, and slope information of a road where the vehicle is located, wherein the target correction coefficient is obtained according to a driving condition of the vehicle; determining a transmission shaft resistance of the vehicle according to the current speed, the weight, the coasting resistance, and the slope information; The axle resistance of the gearbox is multiplied by the target correction coefficient to obtain the correction resistance.

[0038] It should be understood that when calculating the correction resistance, the vehicle driver may have unstable pedal control signals during driving and ignore the acceleration resistance of the vehicle, and thus the target correction coefficient of the vehicle can be calculated, which can be used to improve the reliability of the target gear. The target correction coefficient can be obtained by the corresponding driving condition of the vehicle during the test drive, which can be one or more. After obtaining the target correction coefficient, the slope information of the vehicle, the weight of the vehicle, and the rolling resistance of the vehicle are obtained, and the axle resistance of the vehicle gearbox is calculated according to the weight, the rolling resistance and the slope information, and then the axle resistance is multiplied by the target correction coefficient to obtain the correction resistance, wherein the axle resistance of the gearbox can be the output shaft resistance of the gearbox or the input shaft resistance of the gearbox, and the embodiments of the present disclosure are not limited thereto.

[0039] The axle resistance can be calculated by the following calculation formula.

[0040]

[0041] The correction resistance can be expressed by the following calculation formula.

[0042]

[0043] wherein, is the axle resistance of the vehicle gearbox, is the correction resistance, is the target correction coefficient, V is the current vehicle speed, A, B and C are the rolling resistance coefficients of the vehicle, m is the weight of the vehicle, and i is the sine value of the slope angle of the vehicle, is the first rolling resistance of the vehicle at the current vehicle speed calculated according to the least square method, is the rolling resistance of the vehicle gearbox, is the slope resistance of the vehicle at the slope information, and r is the wheel radius, is the rear axle speed ratio of the vehicle.

[0044] In a possible manner, the target correction coefficient of the vehicle is determined, comprising: determining a target driving condition on a road on which the vehicle travels; determining the target correction coefficient according to a preset corresponding relationship between the target driving condition and the correction coefficient, wherein the preset corresponding relationship is a corresponding relationship between the driving condition and the correction coefficient.

[0045] It should be understood that when the driving condition is one, one correction coefficient can be correspondingly set when the vehicle drives in each driving condition, that is, the corresponding relationship between the driving condition of the vehicle and the correction coefficient can be a preset corresponding relationship. Therefore, in the embodiments of the present disclosure, the driving condition of the road on which the vehicle is located can be determined as the target driving condition, and then the target correction coefficient of the vehicle on the driving road can be determined according to the target driving condition and the preset corresponding relationship.

[0046] In a possible manner, the determining the target correction coefficient of the vehicle comprises: determining a plurality of driving routes, wherein each driving route corresponds to different driving conditions; collecting the number of gear shifts of the vehicle during driving on each driving route; calculating the target correction coefficient of the vehicle according to the whole vehicle dynamics model, each driving route and the number of gear shifts corresponding to each driving route.

[0047] It should be understood that when the driving condition is one, one correction coefficient can be correspondingly set when the vehicle drives in each driving condition, that is, the corresponding relationship between the driving condition of the vehicle and the correction coefficient can be a preset corresponding relationship. Therefore, in the embodiments of the present disclosure, the driving condition of the road on which the vehicle is located can be determined as the target driving condition, and then the target correction coefficient of the vehicle on the driving road can be determined according to the target driving condition and the preset corresponding relationship.

[0048] In the embodiments of the present disclosure, the target correction coefficient is calculated by the whole vehicle dynamics model, which can reduce the period of obtaining the target correction coefficient and can make the obtained target correction coefficient be the optimal correction coefficient, so that when the target correction coefficient is used for subsequent determination of the target gear position, the target gear position can be more accurate, and the number of frequent gear shifts of the vehicle can be reduced.

[0049] By introducing the target correction coefficient to calculate the correction resistance of the vehicle, and calculating the correction resistance of the vehicle according to the current vehicle speed and slope information, and when the correction resistance is used in the subsequent step of determining the target gear position, the accuracy of the target gear position can be improved, so that the frequent gear shifting of the vehicle during driving can be reduced, and the stability of the vehicle during driving can be improved.

[0050] For example, after determining the maximum sustainable torque and the corrected resistance, in the embodiments of the present disclosure, a candidate gear can be determined according to the maximum sustainable torque and the corrected resistance. The candidate gear can be one or multiple. Then a target gear that the vehicle needs to switch to can be determined in the candidate gear. Compared with the related art of controlling the gear of the vehicle according to the motor speed of the vehicle, the accuracy of the target gear can be improved, and thus the stability of the vehicle in driving can be improved.

[0051] In a possible manner, the determining the candidate gear according to the maximum sustainable torque and the corrected resistance comprises: In all gears of the vehicle, a first gear greater than or equal to a first threshold value is determined, wherein the first threshold value is obtained by dividing the corrected resistance by the maximum sustainable torque. When the first gear has a second gear, the second gear is determined as the candidate gear, wherein the second gear is a gear existing in the vehicle. When the first gear does not have the second gear, and the vehicle speed and / or the slope information of the road where the vehicle is located changes, the determination of the new maximum sustainable torque and the new corrected resistance of the vehicle is re-executed, a new first gear greater than or equal to the first threshold value is determined according to the new maximum sustainable torque and the new corrected resistance, and when the new first gear has a new second gear, the new second gear is determined as the candidate gear.

[0052] It should be understood that when the candidate gear is determined, the first threshold value can be obtained by dividing the corrected resistance by the maximum sustainable torque, and a first gear greater than or equal to the first threshold value is determined. The first gear can be one or multiple.

[0053] When the first gear is one, it is determined whether the first gear is the second gear. If yes, the first gear is determined as the target gear. Otherwise, it is determined whether the vehicle speed and the slope information of the road where the vehicle is located change. If yes, the candidate gear is recalculated. If no, no processing is performed.

[0054] When the first gear is multiple, it is determined whether there is a second gear in the multiple first gears. When there is a second gear in the first gears, all the second gears are determined as the candidate gears. Otherwise, it can be represented that the power performance of the vehicle has reached the maximum power performance. It is determined whether the vehicle speed and the slope information of the road where the vehicle is located change. If the vehicle speed and the slope information do not change, the vehicle can not shift gears. If one of the vehicle speed and the slope information changes, the new maximum sustainable torque of the vehicle and the new corrected resistance can be determined again. Then, the new second gear can be determined according to the new maximum sustainable torque and the new corrected resistance, and the new second gear is determined as the candidate gear.

[0055] The first gear greater than or equal to the first threshold value can be calculated by the following calculation formula.

[0056]

[0057] The first threshold value is The first gear is

[0058] For example, after obtaining the candidate gear, the target gear can be determined according to the driving demand of the vehicle to control the vehicle to switch the current gear to the target gear. Compared with the related art, the number of gear shifts of the vehicle in the gear shifting process can be reduced, and the situation of frequent gear shifting of the vehicle can be reduced, thereby reducing the fuel consumption of the vehicle during driving, and reducing the gear shifting time of the vehicle, thereby ensuring the stability of the vehicle during driving.

[0059] In a possible manner, the target gear is determined from the candidate gears according to the driving demand of the vehicle, including: When the driving demand of the vehicle is to minimize the gear ratio of the vehicle, the smallest candidate gear in the candidate gears is determined as the target gear; When the driving demand of the vehicle is to maximize the power performance of the vehicle, the largest candidate gear in the candidate gears is determined as the target gear; When the driving demand of the vehicle is the highest motor efficiency of the vehicle, the motor efficiency value corresponding to each candidate gear is obtained, and the candidate gear corresponding to the highest efficiency value in the multiple efficiency values is determined as the target gear.

[0060] It should be understood that different target gears can be determined by different methods when the target gear is determined according to the driving demand of the vehicle. Specifically, when the driving demand of the vehicle is to minimize the gear ratio of the vehicle, the minimum candidate gear among the candidate gears is determined as the target gear, and when the current gear of the vehicle is controlled to switch to the target gear, the thermal balance of the motor of the vehicle during driving can be best. When the driving demand of the vehicle is to maximize the power performance of the vehicle, the maximum candidate gear among the candidate gears is determined as the target gear, and when the current gear of the vehicle is controlled to switch to the target gear, the power performance of the vehicle during driving can be best. When the driving demand of the vehicle is that the motor efficiency of the vehicle is the highest, the motor efficiency value corresponding to each candidate gear is obtained, the candidate gear corresponding to the highest efficiency value among the plurality of efficiency values is determined as the target gear, and when the current gear of the vehicle is controlled to switch to the target gear, the economic performance of the vehicle during driving can be best.

[0061] By the above technical solution, the target gear is determined among the candidate gears according to different driving demands of the vehicle, which can improve the flexibility of gear selection during driving of the vehicle, and can improve the accuracy of the target gear, thereby reducing the time of gear selection.

[0062] In a possible manner, the method further comprises: determining a resistance value of the vehicle at the current vehicle speed and a maximum sustainable torque of the vehicle at the current vehicle speed; when the maximum sustainable torque of the vehicle at the current vehicle speed is less than a second threshold value, determining that the vehicle has a gear shifting demand, wherein the second threshold value is obtained by dividing the resistance value of the vehicle at the current vehicle speed by the variable gear of the vehicle during driving.

[0063] It should be understood that in the embodiments of the present disclosure, when it is determined that the vehicle has a gear shifting demand, the determination can be made by the resistance value of the vehicle at the current vehicle speed and the maximum sustainable torque at the current vehicle speed. Specifically, when the maximum sustainable torque at the current vehicle speed is less than a second threshold value obtained by dividing the resistance value at the current vehicle speed by the variable gear of the vehicle during driving, it can be determined that the vehicle needs to shift gears at this time. Otherwise, the vehicle does not need to shift gears and can continue to drive at the current gear, which is not limited in the embodiments of the present disclosure. The variable gear of the vehicle during driving can be a gear other than the parking gear and the neutral gear.

[0064] Specifically, it can be represented by the following calculation formula.

[0065]

[0066] The maximum sustainable torque of the vehicle at the current vehicle speed, is a resistance value of the vehicle at a current vehicle speed, is a variable speed gear position of the vehicle in a driving process, and D2 is a second threshold value.

[0067] By the above technical solution, the stability of the shifting power and the passing performance of the vehicle under different vehicle weights, vehicle speeds and driving conditions can be improved, and at the same time, the efficiency optimization principle can be formulated according to the vehicle demand to further improve the fuel economy of the vehicle. By introducing the target correction coefficient, and the target correction coefficient can be obtained according to the driving condition of the vehicle, the reliability of the target gear position can be improved. When calculating the candidate gear position according to the target correction coefficient, the abnormal shifting problem caused by the abnormal running state of the vehicle can be solved to a certain extent. The target gear position determined according to the minimum gear ratio principle can improve the stability of the vehicle in the running process.

[0068] At the same time, the slope information and the gear position can be associated in the embodiment of the present disclosure, and the reliability of the calculation of the minimum demand torque of the vehicle in the stable driving state can be ensured, the control mode is simple, and the slope information can be fully utilized to improve the running stability and safety of the vehicle. The abnormal change of the demand torque caused by the abnormal driving of the driver and other factors is reduced. The selection mode of the target gear position can be adjusted by comprehensively considering the battery and motor performance, efficiency interval and other factors, and the flexibility of the selection of the target gear position can be improved.

[0069] Reference Figure 2 As shown in Figure 2 , the flowchart of the vehicle gear control method according to an exemplary embodiment of the present disclosure is shown. The flow steps of the vehicle gear control method are as follows. Figure 2 S201: determining the resistance value of the vehicle at the current vehicle speed and the maximum sustainable torque of the vehicle at the current vehicle speed.

[0070] S202: determining the current gear position of the vehicle.

[0071] S203: whether the maximum sustainable torque at the current vehicle speed is less than the second threshold value, if the maximum sustainable torque is less than the second threshold value, step S205 is executed, otherwise step S204 is executed.

[0072] S204: maintaining the current gear position.

[0073] S205: determining that the vehicle needs to shift, obtaining the resistance at the target vehicle speed and the maximum sustainable torque at the current vehicle speed.

[0074] S206: determining the first gear position greater than or equal to the first threshold value.

[0075]

[0076] ​S207: Determine whether there is a second gear in the first gear. If yes, execute step S209; otherwise, execute step S208.

[0077] S208: If the vehicle speed or slope information changes, execute step S205. If the vehicle speed or slope information does not change, no gear shifting is performed.

[0078] S209: Determine a target gear from the candidate gears according to the vehicle driving requirements.

[0079] S210: Control the vehicle to switch the current gear to the target gear.

[0080] The specific implementation methods of the above-mentioned process steps have been described in detail above and will not be repeated here. In addition, it should be understood that for the above-mentioned system embodiments, for the sake of simplicity of description, they are all expressed as a series of action combinations, but those skilled in the art should know that the present disclosure is not limited to the order of actions described above. Secondly, those skilled in the art should also know that the embodiments described above are preferred embodiments, and the steps involved are not necessarily required by the present disclosure.

[0081] Based on the same concept, this embodiment also discloses a vehicle gear control device, such as Figure 3 As shown, Figure 3 FIG. 3 is a schematic diagram showing a vehicle gear position control device 300 according to an exemplary embodiment of the present disclosure. Figure 3 , including a first determination module 301, a second determination module 302, a third determination module 303 and a control module 304; The first determining module 301 is configured to determine, when determining that a gear shift is required, the maximum sustainable torque of the vehicle at a target speed and a corrected resistance of the vehicle at a current speed, wherein the target speed is the speed of the vehicle after the gear shift, and the corrected resistance is obtained based on the gearbox shaft resistance of the vehicle; The second determining module 302 is configured to determine the candidate gear according to the maximum sustainable torque and the modified resistance; The third determining module 303 is configured to determine a target gear from the candidate gears according to the driving requirements of the vehicle; The control module 304 is configured to control the vehicle to switch the current gear to the target gear.

[0082] Optionally, the second determining module 302 includes: a fourth determining module, configured to determine a first gear position greater than or equal to a first threshold among all gear positions of the vehicle, wherein the first threshold is obtained by dividing the modified resistance by the maximum sustainable torque; a fifth determining module, configured to determine a second gear as a candidate gear when the second gear exists in the first gear, wherein the second gear is a gear existing in the vehicle; a sixth determining module, configured to re-perform determining a new maximum sustainable torque of the vehicle and a new correction resistance when the second gear does not exist in the first gear and a vehicle speed and / or slope information of a road where the vehicle is located changes, and determine a new first gear greater than or equal to the first threshold value according to the new maximum sustainable torque and the new correction resistance, and determine a new second gear as the candidate gear when the new second gear exists in the new first gear.

[0083] Optionally, the third determining module 303 is configured to: determine a minimum candidate gear in the candidate gears as the target gear when the driving demand of the vehicle is such that a gear ratio of the vehicle is minimized; determine a maximum candidate gear in the candidate gears as the target gear when the driving demand of the vehicle is such that a power performance of the vehicle is maximized; when the driving demand of the vehicle is that a motor efficiency of the vehicle is highest, obtain a motor efficiency value corresponding to each candidate gear, and determine a candidate gear corresponding to a highest efficiency value in the plurality of efficiency values as the target gear.

[0084] Optionally, the apparatus 300 further includes: a seventh determining module, configured to determine a resistance value of the vehicle at the current vehicle speed and a maximum sustainable torque of the vehicle at the current vehicle speed; a judging module, configured to determine that the vehicle has a gear shifting demand when the maximum sustainable torque of the vehicle at the current vehicle speed is less than a second threshold value, wherein the second threshold value is obtained by dividing the resistance value of the vehicle at the current vehicle speed by a gear of the vehicle in a driving process.

[0085] Optionally, the first determining module 301 includes: an eighth determining module, configured to determine a target correction coefficient, a weight, a coasting resistance of the vehicle, and slope information of a road where the vehicle is located, wherein the target correction coefficient is obtained according to a driving condition of the vehicle; a ninth determining module, configured to determine the gearbox shaft resistance of the vehicle according to the current vehicle speed, the weight, the coasting resistance, and the slope information; a first calculating module, configured to perform a multiplication operation on the gearbox shaft resistance and the target correction coefficient to obtain the correction resistance.

[0086] Optionally, the eighth determining module includes: a first sub-determining module configured to determine a target driving condition on a road on which the vehicle travels; a second sub-determining module configured to determine the target correction coefficient according to a preset corresponding relationship between the target driving condition and the target correction coefficient, wherein the preset corresponding relationship is a corresponding relationship between a driving condition and a correction coefficient.

[0087] Optionally, the eighth determining module comprises: a third sub-determining module configured to determine a plurality of driving routes, wherein each driving route corresponds to a different driving condition; a collecting module configured to collect a number of gear shifts of the vehicle during driving on each driving route; a second calculating module configured to calculate the target correction coefficient of the vehicle according to a whole vehicle dynamics model, each driving route, and the number of gear shifts corresponding to each driving route.

[0088] As to the apparatus in the above-mentioned embodiments, the specific manners in which various modules perform operations have been described in detail in the embodiments of the method, and thus will not be described here in detail.

[0089] Based on the same idea, the embodiment further discloses a controller, comprising: a memory having a computer program stored thereon; a processor configured to execute the computer program in the memory to implement the steps of the vehicle gear control method disclosed in the embodiments of the disclosure.

[0090] Based on the same idea, the embodiment further discloses a vehicle comprising the controller disclosed in the embodiments of the disclosure.

[0091] Figure 4 is a block diagram of a vehicle 400 according to an example embodiment. For example, the vehicle 400 can be a hybrid vehicle, or a non-hybrid vehicle, an electric vehicle, a fuel cell vehicle, or other types of vehicles. The vehicle 400 can be an autonomous vehicle or a semi-autonomous vehicle.

[0092] Referring to Figure 4 , the vehicle 400 can include various subsystems, such as an infotainment system 410, a perception system 420, a decision control system 430, a drive system 440, and a computing platform 450. The vehicle 400 can include more or fewer subsystems, and each subsystem can include multiple components. In addition, each subsystem of the vehicle 400 and each component can be interconnected by wired or wireless means.

[0093] In some embodiments, infotainment system 410 can include a communication system, an entertainment system, a navigation system, and the like.

[0094] Sensing system 420 can include several sensors for sensing information of the environment surrounding vehicle 400. For example, sensing system 420 can include a global positioning system (which can be a GPS system, a Beidou system, or other positioning system), an inertial measurement unit (IMU), a lidar, a millimeter wave radar, an ultrasonic radar, and a camera.

[0095] Decision control system 430 can include a computing system, a vehicle controller, a steering system, a throttle, and a braking system.

[0096] Drive system 440 can include components that provide powered motion for vehicle 400. In one embodiment, drive system 440 can include an engine, an energy source, a transmission system, and wheels. The engine can be one or a combination of an internal combustion engine, an electric motor, an air compression engine. The engine is capable of converting energy provided by the energy source into mechanical energy.

[0097] Some or all functions of vehicle 400 are controlled by computing platform 450. Computing platform 450 can include at least one processor 451 and memory 452, and processor 451 can execute instructions 453 stored in memory 452.

[0098] Processor 451 can be any conventional processor, such as commercially available CPUs. The processor can also include a graphics processing unit (GPU), a field programmable gate array (FPGA), a system on chip (SOC), an application specific integrated circuit (ASIC), or a combination thereof.

[0099] Memory 452 can be implemented by any type of volatile or nonvolatile memory or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read only memory (EEPROM), erasable programmable read only memory (EPROM), programmable read only memory (PROM), read only memory (ROM), magnetic memory, flash memory, a magnetic disk, or an optical disk.

[0100] In addition to the instructions 453, the memory 452 can also store data, such as road maps, route information, data of the position, direction, speed, etc. of the vehicle. The data stored by the memory 452 can be used by the computing platform 450.

[0101] In the embodiments of the present disclosure, the processor 451 can execute the instructions 453 to complete all or part of the steps of the vehicle gear control method described above.

[0102] In another exemplary embodiment, a computer readable storage medium including program instructions is also provided, which when executed by a processor, implement the steps of the vehicle gear control method described above. For example, the computer readable storage medium can be the memory 452 described above including program instructions, and the program instructions described above can be executed by the processor 451 of the vehicle 400 to complete the vehicle gear control method described above.

[0103] In another exemplary embodiment, a computer program product is also provided, which contains a computer program capable of being executed by a programmable device, and the computer program has code portions for executing the vehicle gear control method described above when executed by the programmable device.

[0104] The preferred embodiments of the present disclosure are described in detail above with reference to the accompanying drawings, but the present disclosure is not limited to the specific details in the above-described embodiments. Within the technical concept of the present disclosure, various simple modifications can be made to the technical solutions of the present disclosure, and these simple modifications all belong to the protection scope of the present disclosure.

[0105] In addition, it should be noted that each specific technical feature described in the above specific embodiments can be combined in any appropriate manner without contradiction, and in order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0106] Furthermore, any combination of the various different embodiments of the present disclosure can also be made, as long as it does not deviate from the idea of the present disclosure, it should also be considered as disclosed by the present disclosure.

Claims

1. A vehicle gear control method, characterized by, The method comprises: when it is determined that the vehicle has a shift demand, determining a maximum sustainable torque of the vehicle at a target vehicle speed and a modified resistance of the vehicle at a current vehicle speed, wherein the target vehicle speed is a vehicle speed of the vehicle after a shift, and the modified resistance is obtained according to a gearbox shaft resistance in the vehicle; determining a candidate gear position according to the maximum sustainable torque and the modified resistance; determining a target gear position in the candidate gear position according to a driving demand of the vehicle; controlling the vehicle to switch a current gear position to the target gear position.

2. The vehicle gear control method according to claim 1, characterized by, The method further comprises: determining a resistance value of the vehicle at the current vehicle speed and a maximum sustainable torque of the vehicle at the current vehicle speed; when the maximum sustainable torque of the vehicle at the current vehicle speed is less than a second threshold value, determining that the vehicle has a shift demand, wherein the second threshold value is obtained by dividing the resistance value of the vehicle at the current vehicle speed by a shift gear position of the vehicle during driving. The modified resistance of the vehicle at the current vehicle speed is obtained by the following method:

3. The vehicle gear control method according to claim 1, characterized by, determining a target correction coefficient, a weight, a sliding resistance of the vehicle, and slope information of a road where the vehicle is located, wherein the target correction coefficient is obtained according to a driving condition of the vehicle; determining the gearbox shaft resistance of the vehicle according to the current vehicle speed, the weight, the sliding resistance, and the slope information; multiplying the gearbox shaft resistance by the target correction coefficient to obtain the modified resistance. The method further comprises:

4. The vehicle gear control method according to claim 1, characterized by, determining a target correction coefficient of the vehicle. ​ ​ 5. The vehicle gear control method according to any one of claims 1 to 4, characterized by, ​ ​ ​ ​ 6. The vehicle gear control method according to claim 5, characterized by, ​ determine a target driving condition on a road where the vehicle travels; determine the target correction coefficient according to a preset corresponding relationship between the target driving condition and the target correction coefficient, wherein the preset corresponding relationship is a corresponding relationship between a driving condition and a correction coefficient.

7. The vehicle gear control method according to claim 6, characterized by, The determining of the target correction coefficient of the vehicle comprises: determining a plurality of driving routes, wherein each driving route corresponds to a different driving condition; collecting a number of gear shifts during driving of the vehicle on each driving route; calculating the target correction coefficient of the vehicle according to a vehicle dynamics model, each driving route, and the number of gear shifts corresponding to each driving route.

8. A vehicle gear control device, characterized by comprising: comprise a first determining module, a second determining module, a third determining module, and a control module; The first determining module is configured to determine the maximum sustainable torque of the vehicle at a target vehicle speed and a correction resistance of the vehicle at a current vehicle speed when the vehicle has a gear shift demand, wherein the target vehicle speed is a vehicle speed of the vehicle after gear shifting, and the correction resistance is obtained according to a gearbox shaft resistance of the vehicle; The second determining module is configured to determine the candidate gear according to the maximum sustainable torque and the correction resistance; The third determining module is configured to determine a target gear from the candidate gears according to a driving demand of the vehicle; The control module is configured to control the vehicle to switch a current gear to the target gear.

9. A controller characterized by comprising: comprise: a memory having a computer program stored thereon; a processor configured to execute the computer program in the memory to implement the steps of the method of any one of claims 1-7.

10. A vehicle characterized by comprising: comprise the controller of claim 9.

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