Gear shifting control method and apparatus for pure-electric commercial vehicle having dual electric drive axles

Abstract

The present invention belongs to the technical field of electric vehicles. Provided are a gear shifting control method and apparatus for a pure-electric commercial vehicle having dual electric drive axles. The method comprises: acquiring a total vehicle power currently required by a driver, a traveling map and data of vehicle ahead; when the total vehicle power is less than a target power threshold, the slope of an uphill / downhill in the traveling map is less than a first target slope threshold, and it is determined, on the basis of the data of the vehicle ahead, that there is no obstacle vehicle traveling in front of the host vehicle, controlling one of dual electric drive axles to shift to neutral, controlling a transmission chain between the dual electric drive axles to be disconnected, and controlling the other electric drive axle to perform driving and energy recovery; and when it is determined, on the basis of the traveling map, that there is an uphill in front of the host vehicle and the slope of the uphill is greater than a second target slope threshold, before the host vehicle travels uphill, controlling the electric drive axle that has been shifted to neutral to shift to a first target gear. The present invention can achieve the aim of reducing the energy consumption of a vehicle without affecting the power response of the vehicle.

Description

Shift control method and device for dual-motor-drive-axle pure electric commercial vehicle TECHNICAL FIELD

[0001] The present application relates to the technical field of electric vehicles, in particular to a shift control method and device for dual-motor-drive-axle pure electric commercial vehicle. BACKGROUND

[0002] Compared with the existing central drive vehicle, the pure electric commercial vehicle configured with dual-motor-drive-axle has generally larger total power of motor, but in the actual operation scene of the vehicle, the power demand of the vehicle is actually not so large in a considerable part of the cases, resulting in low motor load rate of the dual-motor-drive-axle pure electric commercial vehicle, and further resulting in low motor efficiency, which has negative impact on the economy of the vehicle. In order to solve this problem, on the one hand, the working condition efficiency of the drive system is improved through effective motor torque distribution strategy. Further, for the pure electric commercial vehicle configured with dual-motor-drive-axle, in the case of low load rate of the vehicle, it can be considered to use only one drive axle to drive the vehicle, and the other drive axle does not work. However, the drive axle that does not work will have oil stirring loss and motor field weakening loss, etc., increasing energy consumption. If the transmission chain of the drive axle that does not work is disconnected, when the power demand of the vehicle becomes large and the driver steps on the accelerator deeply, the power system capacity response cannot keep up, which will result in poor dynamic performance of the vehicle. Therefore, the existing technical solution cannot reduce the energy consumption of the vehicle without affecting the power response of the vehicle. SUMMARY

[0003] Therefore, it is necessary to provide a shift control method and device for dual-motor-drive-axle pure electric commercial vehicle to solve the technical problem that the existing technical solution cannot reduce the energy consumption of the vehicle without affecting the power response of the vehicle.

[0004] In order to solve the above problems, the present application provides a shift control method for dual-motor-drive-axle pure electric commercial vehicle, comprising:

[0005] obtaining the current demand of the vehicle power of the driver, the driving map and the front vehicle data of the vehicle;

[0006] in the case that the current demand of the vehicle power of the driver is less than the target power threshold, the slope of the uphill and downhill in the driving map is less than the first target slope threshold, and it is determined based on the front vehicle data that there is no obstructive vehicle in front of the vehicle, one of the dual-motor-drive-axles is controlled to engage the neutral gear, the transmission chain between the dual-motor-drive-axles is controlled to be disconnected, and the other drive axle is controlled to drive and recover energy;

[0007] in the case that it is determined based on the driving map that there is an uphill in front of the vehicle and the slope of the uphill is greater than the second target slope threshold, before the vehicle climbs uphill, the drive axle that has engaged the neutral gear is controlled to engage the first target gear.

[0008] In a possible implementation, the first target slope threshold is determined based on the following steps:

[0009] obtaining a total vehicle mass, a wheel rolling resistance coefficient, a total vehicle air resistance coefficient, a total vehicle wind area, a current vehicle speed, and a first total vehicle demand power of the vehicle driving on a road with a slope of the first target slope threshold;

[0010] obtaining the first target slope threshold based on the total vehicle mass, the wheel rolling resistance coefficient, the total vehicle air resistance coefficient, the total vehicle wind area, the current vehicle speed, and the first total vehicle demand power.

[0011] In a possible implementation, a calculation formula of the first target slope threshold is as follows: P1 = (mgf + C D Au 2 / 21.15 + mgi0)u / 3600

[0012] wherein m is the total vehicle mass, g is a gravitational acceleration constant, f is the wheel rolling resistance coefficient, C D is the total vehicle air resistance coefficient, A is the total vehicle wind area, u is the current vehicle speed, i0 is the first target slope threshold, and P1 is the first total vehicle demand power.

[0013] In a possible implementation, the second target slope threshold is determined based on the following steps:

[0014] obtaining a total vehicle mass, a wheel rolling resistance coefficient, a total vehicle air resistance coefficient, a total vehicle wind area, a current vehicle speed, and a second total vehicle demand power of the vehicle driving on a road with a slope of the second target slope threshold;

[0015] obtaining the second target slope threshold based on the total vehicle mass, the wheel rolling resistance coefficient, the total vehicle air resistance coefficient, the total vehicle wind area, the current vehicle speed, and the second total vehicle demand power.

[0016] In a possible implementation, a calculation formula of the second target slope threshold is as follows: P2 = (mgf + C D Au 2 / 21.15 + mgi1)u / 3600

[0017] wherein m is the total vehicle mass, g is a gravitational acceleration constant, f is the wheel rolling resistance coefficient, C D is the total vehicle air resistance coefficient, A is the total vehicle wind area, u is the current vehicle speed, i1 is the second target slope threshold, and P2 is the second total vehicle demand power.

[0018] In a possible implementation, the first target gear is obtained based on the following steps:

[0019] acquire a current vehicle speed, a motor speed and a wheel radius of the vehicle;

[0020] determine a target gearbox speed ratio based on the product of the motor speed and the wheel radius being at the current vehicle speed;

[0021] determine a first target gear position based on the target gearbox speed ratio.

[0022] In a possible implementation, the shift control method of the dual electric drive axle pure electric commercial vehicle further includes:

[0023] when it is determined based on the driving map that there is a downhill ahead of the vehicle or that there is an obstacle ahead of the vehicle, control the drive axle that has engaged the neutral gear to engage the second target gear position.

[0024] In a possible implementation, the determining, based on the driving map, that there is a downhill ahead of the vehicle includes:

[0025] acquire a slope within a first target distance ahead of the vehicle from the driving map;

[0026] determine a vehicle regenerative braking power required for maintaining the current vehicle speed when the vehicle is driving on a downhill road;

[0027] determine a downhill target slope based on the vehicle regenerative braking power, a total mass of the vehicle, a gravitational acceleration constant, a wheel rolling resistance coefficient, a vehicle wind resistance coefficient, a vehicle wind area and the current vehicle speed;

[0028] when the slope within the first target distance ahead of the vehicle is greater than the downhill target slope, determine that there is a downhill ahead of the vehicle.

[0029] In a possible implementation, the determining, based on the driving map, that there is an obstacle ahead of the vehicle includes:

[0030] acquire a vehicle speed of a vehicle closest to the vehicle ahead of the vehicle from the driving map;

[0031] when it is determined that the vehicle speed of the vehicle closest to the vehicle ahead of the vehicle is less than a target vehicle speed threshold, determine that there is an obstacle ahead of the vehicle.

[0032] In another aspect, the present application further provides a shift control device of a dual electric drive axle pure electric commercial vehicle, comprising:

[0033] a data acquisition module, configured to acquire a current vehicle speed, a motor speed and a wheel radius of the vehicle;

[0034] The first control module of the double electric drive axle is used for controlling one of the drive axles of the double electric drive axle to be in neutral gear, controlling the drive chain between the double electric drive axles to be disconnected, and controlling the other drive axle to drive and recover energy when the current demand of the driver for the vehicle power is less than a target power threshold, the slope of the uphill and downhill in the driving map is less than a first target slope threshold, and it is determined that there is no vehicle in front of the vehicle based on the front vehicle data.

[0035] The second control module of the double electric drive axle is used for controlling the drive axle that has been in neutral gear to be in a first target gear before the vehicle climbs uphill when it is determined that there is an uphill in front of the vehicle based on the driving map and the slope of the uphill is greater than a second target slope threshold.

[0036] The beneficial effects of the above implementation manner are that the gear shifting control method and device of the double electric drive axle pure electric commercial vehicle provided by the application can determine that the vehicle demand power is small when the current demand of the driver for the vehicle power is less than a target power threshold, the slope of the uphill and downhill in the driving map is less than a first target slope threshold, and it is determined that there is no vehicle in front of the vehicle based on the front vehicle data, control one of the drive axles of the double electric drive axle to be in neutral gear, control the drive chain between the double electric drive axles to be disconnected, control the other drive axle to drive and recover energy, improve the motor load rate, reduce a part of the oil stirring loss and motor loss, and optimize the vehicle economy; it is determined that the vehicle has a large power demand when it is determined that there is an uphill in front of the vehicle based on the driving map and the slope of the uphill is greater than a second target slope threshold, control the drive axle that has been in neutral gear to be in a first target gear before the vehicle climbs uphill, control the drive axle that has been in neutral gear to be in a suitable gear in advance, ensure that the vehicle has enough power when climbing uphill, and avoid affecting the power response of the vehicle; thereby reduce the energy consumption of the vehicle without affecting the power response of the vehicle, and improve the vehicle economy. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description only some embodiments of the application, and other drawings can be obtained by those skilled in the art without creative labor based on these drawings.

[0038] FIG. 1 is a flowchart of one embodiment of the gear shifting control method of the double electric drive axle pure electric commercial vehicle provided by the application;

[0039] FIG. 2 is a flowchart of another embodiment of the gear shifting control method of the double electric drive axle pure electric commercial vehicle provided by the application;

[0040] FIG. 3 is a principle block diagram of one embodiment of the gear shifting control device of the double electric drive axle pure electric commercial vehicle provided by the application;

[0041] Fig. 4 is a structural schematic diagram of an embodiment of the electronic device provided by the present application. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present application will be clearly and completely described in connection with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person skilled in the art without creative work fall within the protection scope of the present application.

[0043] In the description of the embodiments of the present application, the meaning of “plurality” is two or more, unless otherwise specified.

[0044] In the embodiments of the present application, the terms “comprising” and “having” and any variations thereof are intended to cover the inclusions that are not exclusive, for example, a process, method, device, product or equipment comprising a series of steps or modules does not have to be limited to the clearly listed steps or modules, but can include other steps or modules that are not clearly listed or inherent to the process, method, product or equipment.

[0045] The naming or numbering of steps appearing in the embodiments of the present application does not mean that the steps in the method flow must be performed in the time / logical order indicated by the naming or numbering. The flow steps that have been named or numbered can change the execution order according to the technical purpose to be achieved, as long as the same or similar technical effects can be achieved.

[0046] Reference to “embodiments” in this document means that the specific features, structures or properties described in connection with the embodiments can be included in at least one embodiment of the present application. The phrase appears at various places in the specification does not necessarily mean the same embodiment, nor is it an independent or alternative embodiment to other embodiments. A person skilled in the art explicitly and implicitly understands that the embodiments described herein can be combined with other embodiments.

[0047] The present application provides a shift control method and device for a double-electric-drive-bridge pure electric commercial vehicle, which are described below respectively.

[0048] As shown in Fig. 1, the present application provides a shift control method for a double-electric-drive-bridge pure electric commercial vehicle, which comprises:

[0049] S101, obtaining the current demand of the driver for the vehicle power, the driving map and the front vehicle data of the vehicle;

[0050] S102, in a case that the current demand of the driver is less than the target power threshold, the slope of the uphill and downhill in the driving map is less than the first target slope threshold, and it is determined based on the front vehicle data that there is no obstructive vehicle in front of the vehicle, one of the two electric drive axles is controlled to be in neutral, the transmission chain between the two electric drive axles is controlled to be disconnected, and the other electric drive axle is controlled to drive and recover energy;

[0051] S103, in a case that it is determined based on the driving map that there is an uphill in front of the vehicle and the slope of the uphill is greater than the second target slope threshold, the drive axle that has been controlled to be in neutral is controlled to be in the first target gear before the vehicle climbs the uphill.

[0052] It can be understood that the shift control method for a pure electric commercial vehicle with double electric drive axles provided by the application is suitable for a pure electric commercial vehicle with a double electric drive axle configuration, and specifically as follows:

[0053] When the current demand of the driver is small, and there is no obvious uphill and downhill in front of the vehicle based on the predictive map, and there is no slow vehicle to obstruct the normal driving of the vehicle, one of the drive axles is controlled to be in neutral, the transmission chain is disconnected, and the other drive axle is used to drive and recover energy, thereby improving the motor load rate and reducing a part of the oil stirring loss and motor loss.

[0054] When it is detected based on the map data that there is an uphill in front of the road and the slope is greater than a certain value, the drive axle that has been controlled to be in neutral is controlled to be in a suitable gear in advance to ensure that the vehicle has enough power when climbing the uphill.

[0055] When it is detected based on the map data that there is a downhill in front of the road or a slow vehicle is about to obstruct the normal driving of the vehicle, the drive axle that has been controlled to be in neutral is controlled to be in a suitable gear in advance to ensure that the vehicle has enough ability when regenerative braking.

[0056] The method provided by the application controls one of the two electric drive axles to be in neutral when the demand power of the vehicle is small, uses the other axle to drive, reduces the oil stirring loss and motor field weakening loss, and optimizes the economy of the whole vehicle. When it is identified that the vehicle will have a large power demand, such as driving power demand or regenerative braking energy recovery power demand, or when the vehicle is about to climb an uphill, the drive axle that has been controlled to be in neutral is controlled to be in a suitable gear in advance, so as to avoid affecting the power response of the whole vehicle. While not affecting the power response of the vehicle, the economy of the whole vehicle is improved.

[0057] In some embodiments, the first target slope threshold is determined based on the following steps:

[0058] The total mass of the vehicle, the wheel rolling resistance coefficient, the total vehicle wind resistance coefficient, the total vehicle wind area, the current vehicle speed, and the first whole vehicle demand power of the vehicle driving on a road with a slope of the first target slope threshold are obtained.

[0059] obtaining a first target slope threshold based on the total mass of the vehicle, the wheel rolling resistance coefficient, the total vehicle air resistance coefficient, the total vehicle frontal area, the current vehicle speed and the first total vehicle demand power.

[0060] It can be understood that a sensor for measuring the total mass of the vehicle is arranged on the vehicle, and the total mass of the vehicle is obtained through the sensor and uploaded to the CAN bus. The wheel rolling resistance coefficient, the total vehicle air resistance coefficient, the total vehicle frontal area and other parameters can be obtained in advance and then set. The vehicle speed can be detected based on the vehicle speed sensor.

[0061] In some embodiments, the calculation formula of the first target slope threshold is as follows: P1=(mgf+C D Au 2 / 21.15+mgi0)u / 3600

[0062] Wherein, m is the total mass of the vehicle, g is the gravitational acceleration constant, f is the wheel rolling resistance coefficient, C D is the total vehicle air resistance coefficient, A is the total vehicle frontal area, u is the current vehicle speed, i0 is the first target slope threshold, and P1 is the first total vehicle demand power.

[0063] It can be understood that the first target slope threshold i0 corresponds to the motor rated power, so as to calculate i0, when the slope i is less than i0, it can be judged that there is no obvious uphill or downhill in front.

[0064] In some embodiments, the second target slope threshold is determined based on the following steps:

[0065] obtaining the total mass of the vehicle, the wheel rolling resistance coefficient, the total vehicle air resistance coefficient, the total vehicle frontal area, the current vehicle speed, and the second total vehicle demand power of the vehicle driving on the road with the second target slope threshold;

[0066] obtaining a second target slope threshold based on the total mass of the vehicle, the wheel rolling resistance coefficient, the total vehicle air resistance coefficient, the total vehicle frontal area, the current vehicle speed and the second total vehicle demand power.

[0067] In some embodiments, the calculation formula of the second target slope threshold is as follows: P2=(mgf+C D Au 2 / 21.15+mgi1)u / 3600

[0068] Wherein, m is the total mass of the vehicle, g is the gravitational acceleration constant, f is the wheel rolling resistance coefficient, C DC d is the whole vehicle wind resistance coefficient, A is the whole vehicle wind area, u is the current vehicle speed, i1 is the second target slope threshold, P2 is the second whole vehicle demand power.

[0069] It can be understood that the value of P2 can be the rated power of the motor; when the slope i is detected to be greater than i1, the drive axle which has been engaged in the neutral gear is controlled to engage in the appropriate gear S in advance by a distance d3 before the first occurrence of i being greater than i1.

[0070] In some embodiments, the first target gear is obtained based on the following steps:

[0071] obtaining the current vehicle speed, the motor speed and the wheel radius of the vehicle;

[0072] determining the target gearbox speed ratio based on the product of the motor speed and the wheel radius being at the current vehicle speed;

[0073] determining the first target gear based on the target gearbox speed ratio.

[0074] In some embodiments, the gear shifting control method for the double electric drive axle pure electric commercial vehicle further comprises:

[0075] when it is determined based on the driving map that there is a downhill ahead of the vehicle or that there is an obstacle ahead of the vehicle, controlling the drive axle which has been engaged in the neutral gear to engage in the second target gear.

[0076] In some embodiments, determining based on the driving map that there is a downhill ahead of the vehicle comprises:

[0077] obtaining the slope within a first target distance ahead of the vehicle from the driving map;

[0078] determining the whole vehicle regenerative braking power required to maintain the current vehicle speed when the vehicle is driving on a downhill road;

[0079] determining the downhill target slope based on the whole vehicle regenerative braking power, the whole vehicle total mass, the gravitational acceleration constant, the wheel rolling resistance coefficient, the whole vehicle wind resistance coefficient, the whole vehicle wind area and the current vehicle speed;

[0080] when the slope within the first target distance ahead of the vehicle is greater than the downhill target slope, determining that there is a downhill ahead of the vehicle.

[0081] In some embodiments, determining based on the driving map that there is an obstacle ahead of the vehicle comprises:

[0082] obtaining the vehicle speed of the vehicle closest to the vehicle ahead of the vehicle from the driving map;

[0083] when it is determined that the vehicle speed of the vehicle closest to the vehicle ahead of the vehicle is less than a target vehicle speed threshold, determining that there is an obstacle ahead of the vehicle.

[0084] In some embodiments, the whole vehicle power currently required by the driver is obtained, comprising:

[0085] The current torque and current speed of the two motors of the dual motor drive axle are obtained;

[0086] The current power of the first motor of the two motors of the dual motor drive axle is determined based on the current torque and current speed of the first motor, and the current power of the second motor of the two motors of the dual motor drive axle is determined based on the current torque and current speed of the second motor;

[0087] The whole vehicle power currently required by the driver is obtained based on the sum of the current power of the first motor and the current power of the second motor.

[0088] In some embodiments, as shown in FIG. 2, the gear shifting control method of the dual motor drive axle pure electric commercial vehicle includes the following steps:

[0089] Step S201: When the current whole vehicle power Pr required by the driver is small, and there is no obvious uphill or downhill ahead based on the driving map, and there is no slow vehicle to hinder the normal driving of the vehicle, one of the drive axles is controlled to engage in neutral, the transmission chain is disconnected, and the other drive axle is used for driving and energy recovery, thereby improving the motor load rate and reducing a part of the oil stirring loss and motor loss;

[0090] Specifically, the whole vehicle power Pr required by the driver is:

[0091] Pr=Tm1*n m1 / 9550+Tm2*n m2 / 9550

[0092] In the formula, Tm1 is the current torque of the motor of the drive axle 1, n m1 is the current speed of the motor of the drive axle 1, Tm2 is the current torque of the motor of the drive axle 2, n m2 is the current speed of the motor of the drive axle 2, and the above data can be obtained in real time through the CAN bus; When the whole vehicle power Pr required by the driver is less than a certain value P0, the preferred P0 can be the rated power of the motor, and a certain time t0 is maintained, and the preferred t0 can be 3 seconds, that is, the whole vehicle power Pr required by the current driver is determined to be small;

[0093] Further, it is determined that there is no obvious uphill or downhill ahead based on the predictive map: the slope i within a distance d0 ahead is obtained from the map module, the preferred distance d0 can be 3 km, and it is determined whether the slope i is less than a certain value i0, wherein i0 can be initially selected by the following formula: P1=(mgf+C D Au 2 / 21.15+mgi0)u / 3600

[0094] wherein m is the total mass of the vehicle, g is the gravity acceleration constant, f is the wheel rolling resistance coefficient, C D is the total vehicle wind resistance coefficient, A is the total vehicle wind area, u is the current vehicle speed, i0 is the first target slope threshold, P1 is the first total vehicle demand power.

[0095] The total vehicle demand power P1 corresponding to the slope i0 can take the rated power of the motor, so as to calculate i0, when the slope i is less than i0, it can be judged that there is no obvious uphill and downhill in front.

[0096] Further, it is judged that there is no slow vehicle in front to hinder the normal driving of the vehicle: the speed u1 of the vehicle closest to the front within a certain distance d1 is obtained from the map module, preferably, d1 can be taken as 500m, whether the speed u1 is less than a certain speed u0 is judged, preferably, u0 can take the speed limit speed u max minus 10, the speed limit speed u max can be obtained through the map module, when the speed u1 is not less than u0, it can be judged that there is no slow vehicle in front to hinder the normal driving of the vehicle; one of the drive axles is engaged into neutral, the transmission chain is disconnected, and the other drive axle is used for driving and energy recovery; preferably, in order to make the two drive axles wear evenly, the above one drive axle can be drive axle 1, and the other axle is drive axle 2, after the vehicle drives a certain mileage, preferably, for example, after driving 100km, the above one drive axle can be switched to drive axle 2, and the other axle is switched to drive axle 1, and the switching is repeated.

[0097] Step S202: when it is detected based on the map data that there is an uphill in front of the road, and the slope i is greater than a certain value i1, the drive axle engaged into neutral is controlled to engage into the appropriate gear in advance to ensure that the vehicle has enough power when climbing uphill;

[0098] Specifically, the slope i1 within a distance d2 in front is obtained from the map module, preferably, the distance d1 can be taken as 3km, whether the slope i is less than a certain value i1 is judged, wherein i1 can be calculated by the following formula: P2=(mgf+C D Au 2 / 21.15+mgi1)u / 3600

[0099] wherein m is the total mass of the vehicle, g is the gravity acceleration constant, f is the wheel rolling resistance coefficient, C D is the total vehicle wind resistance coefficient, A is the total vehicle wind area, u is the current vehicle speed, i1 is the second target slope threshold, P2 is the second total vehicle demand power.

[0100] The value of P2 can be the rated power of the motor; when the slope i is detected to be greater than i1, the drive axle that has been engaged in the neutral gear is controlled to be engaged in the appropriate gear S a distance d3 before the first time i is greater than i1.

[0101] Preferably, the distance d3 can be 200 m, and the appropriate gear S can be calculated by the following formula: Ra=0.377rn1 / u

[0102] In the formula, Ra is the gear ratio corresponding to the gear S, r is the wheel radius, and n1 is the motor speed. Taking the electric drive axle matched with the 2AMT as an example, the gearbox has two gears, 1st gear and 2nd gear, and the corresponding gear ratios are 45.5 and 15.5, respectively. By substituting Ra equal to 45.5 and 15.5 into the above formula, two values of the motor speed n1 are calculated, and it is determined which of the two values is located in the speed interval n L and n H Preferably, the speed interval n L and n H can be determined according to the high-efficiency interval of the motor system efficiency map, for example, n L is 3000 rpm, and n H is 7500 rpm.

[0103] Step S203: When it is detected based on the map data that there is a downhill in front of the road or a slow vehicle is about to hinder the normal driving of the vehicle, the drive axle that has been engaged in the neutral gear is controlled to be engaged in the appropriate gear in advance to ensure that the vehicle has sufficient ability when regenerative braking.

[0104] Specifically, whether there is a downhill in front of the road is detected based on the map data: the slope i within a distance d4 in front is obtained from the map module, and the distance d4 is preferably 3 km. It is determined whether the slope i is greater than a certain value i2, wherein i2 can be initially selected by solving and calculating the following formula: P3=(mgi2-mgf-CDAu2 / 21.15)u / 3600

[0105] In the formula, P3 is the whole vehicle regenerative braking power required to maintain the current vehicle speed u on the slope with the slope i2, and P3 can be the rated power of the motor. When the slope i is greater than i2, it is determined that there is a downhill demand in front of the road.

[0106] Further, it is judged whether a slow vehicle is about to hinder the normal driving of the vehicle: the vehicle speed u2 of the vehicle closest to the vehicle within a distance d5 in front of the vehicle is obtained from the map module, preferably, d5 can be 200 m, and it is judged whether the vehicle speed u2 is less than a certain vehicle speed u0, when the vehicle speed u2 is less than u0, it is judged that a slow vehicle is about to hinder the normal driving of the vehicle in front; before i is greater than i2 or u2 is less than u0 for the first time, the judgment condition closer to the current vehicle position is taken, and the drive axle with engaged neutral is controlled to engage the appropriate gear S in advance by a distance d2, so as to ensure that the vehicle has enough ability when regenerative braking.

[0107] As shown in Fig. 3, the application also provides a shift control device 300 of a double electric drive axle pure electric commercial vehicle, comprising:

[0108] A data acquisition module 301 is configured to acquire the current demand of the driver for the vehicle power, a driving map and front vehicle data of the vehicle;

[0109] A double electric drive axle first control module 302 is configured to control one of the double electric drive axles to engage neutral and control the drive chain between the double electric drive axles to be disconnected, and control the other drive axle to drive and recover energy, when the current demand of the driver for the vehicle power is less than a target power threshold, the slope of the uphill and downhill in the driving map is less than a first target slope threshold, and it is determined based on the front vehicle data that there is no hindering vehicle in front of the vehicle.

[0110] A double electric drive axle second control module 303 is configured to control the drive axle engaged in neutral to engage the first target gear before the vehicle climbs uphill, when it is determined based on the driving map that there is an uphill in front of the vehicle and the slope of the uphill is greater than a second target slope threshold.

[0111] The shift control device of the double electric drive axle pure electric commercial vehicle provided by the above embodiment can realize the technical solutions described in the shift control method embodiment of the double electric drive axle pure electric commercial vehicle, and the principles of the implementation of the above modules or units can be referred to the corresponding content in the shift control method embodiment of the double electric drive axle pure electric commercial vehicle, which will not be described here.

[0112] As shown in Fig. 4, the application also provides an electronic device 400. The electronic device 400 includes a processor 401, a memory 402 and a display 403. Fig. 4 only shows part of the components of the electronic device 400, but it should be understood that all the shown components are not required, and more or fewer components can be alternatively implemented.

[0113] The memory 402 can be an internal storage unit of the electronic device 400, such as a hard disk or a memory of the electronic device 400 in some embodiments. The memory 402 can also be an external storage device of the electronic device 400, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device 400 in other embodiments.

[0114] Further, the memory 402 can include both an internal storage unit and an external storage device of the electronic device 400. The memory 402 is used to store application software installed on the electronic device 400 and various types of data.

[0115] The processor 401 can be a central processing unit (CPU), a microprocessor, or other data processing chip in some embodiments, used to run program codes or process data stored in the memory 402, such as the shift control method of the double electric drive axle pure electric commercial vehicle in the present application.

[0116] The display 403 can be an LED display, a liquid crystal display, a touch liquid crystal display, an OLED (Organic Light-Emitting Diode) touch, etc. in some embodiments. The display 403 is used to display information on the electronic device 400 and to display a visual user interface. The components 401-403 of the electronic device 400 communicate with each other through a system bus.

[0117] In some embodiments of the present application, when the processor 401 executes the shift control program of the double electric drive axle pure electric commercial vehicle in the memory 402, the following steps can be implemented:

[0118] Obtaining the current demand of the driver for the vehicle power, the driving map, and the front vehicle data of the vehicle;

[0119] In the case that the current demand of the driver for the vehicle power is less than the target power threshold, the slope of the uphill and downhill in the driving map is less than the first target slope threshold, and it is determined based on the front vehicle data that there is no obstructive vehicle in front of the vehicle, one of the double electric drive axles is controlled to engage in neutral, the transmission chain between the double electric drive axles is controlled to be disconnected, and the other drive axle is controlled to drive and recover energy;

[0120] In the case that it is determined based on the driving map that there is an uphill in front of the vehicle and the slope of the uphill is greater than the second target slope threshold, the drive axle that has engaged in neutral is controlled to engage in the first target gear before the vehicle climbs uphill.

[0121] It should be understood that, in addition to the above functions, the processor 401 can also implement other functions when executing the shift control program of the double-electric-drive-bridge pure electric commercial vehicle in the memory 402. For details, refer to the descriptions of the corresponding method embodiments.

[0122] Further, the type of the electronic device 400 is not specifically limited in the embodiments of the present application. The electronic device 400 can be a mobile phone, a tablet computer, a personal digital assistant (PDA), a wearable device, a laptop, or the like. Exemplary embodiments of the portable electronic device include, but are not limited to, a portable electronic device running an IOS, an android, a microsoft, or other operating system. The portable electronic device can also be another portable electronic device, such as a laptop having a touch-sensitive surface (e.g., a touch panel). It should also be understood that in some other embodiments of the present application, the electronic device 400 can not be a portable electronic device, but a desktop computer having a touch-sensitive surface (e.g., a touch panel).

[0123] In another aspect, the present application also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the shift control method of the double-electric-drive-bridge pure electric commercial vehicle provided by the above method. The method comprises:

[0124] obtaining the current demand of the vehicle power of the driver, a driving map, and the front vehicle data of the vehicle;

[0125] when the current demand of the vehicle power of the driver is less than a target power threshold, the slope of the uphill and downhill in the driving map is less than a first target slope threshold, and it is determined based on the front vehicle data that there is no obstructive vehicle in front of the vehicle, controlling one of the double-electric-drive-bridge to engage in neutral, and controlling the transmission chain between the double-electric-drive-bridge to be disconnected, and controlling the other drive axle to drive and recover energy;

[0126] when it is determined based on the driving map that there is an uphill in front of the vehicle and the slope of the uphill is greater than a second target slope threshold, before the vehicle climbs uphill, controlling the drive axle that has engaged in neutral to engage in a first target gear.

[0127] Those skilled in the art can understand that all or part of the processes of the above-mentioned embodiments can be completed by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium. The computer-readable storage medium includes a magnetic disk, an optical disk, a read-only memory, a random access memory, and the like.

[0128] The shift control method and device of the dual-motor-drive-bridge pure electric commercial vehicle provided by the application are described in detail above, and the principles and implementation manners of the application are described by using specific examples in this paper; the above example is only used to help understand the method of the application and its core idea; meanwhile, for those skilled in the art, according to the idea of the application, the specific implementation manners and application ranges will be changed, and the above description should not be understood as a limitation on the application.

Claims

1. A shift control method of a dual-motor-drive bridge pure electric commercial vehicle, characterized in that, The method comprises: acquiring the current demand of the driver, the vehicle map, and the front vehicle data of the vehicle; when the current demand of the driver is less than the target power threshold, the slope of the uphill / downhill in the vehicle map is less than the first target slope threshold, and it is determined based on the front vehicle data that there is no obstructive vehicle in front of the vehicle, controlling one of the two drive axles to be in neutral, disconnecting the transmission chain between the two drive axles, and controlling the other drive axle to drive and recover energy; when it is determined based on the vehicle map that there is an uphill in front of the vehicle and the slope of the uphill is greater than the second target slope threshold, before the vehicle climbs the uphill, controlling the drive axle that has been in neutral to be in the first target gear.

2. The shift control method of a dual-motor-drive two-axle pure electric commercial vehicle according to claim 1, characterized in that, The first target slope threshold is determined based on the following steps: acquiring the total mass of the vehicle, the wheel rolling resistance coefficient, the vehicle wind resistance coefficient, the vehicle frontal area, the current speed, and the first vehicle demand power when the vehicle drives on a road with a slope of the first target slope threshold; based on the total mass of the vehicle, the wheel rolling resistance coefficient, the vehicle wind resistance coefficient, the vehicle frontal area, the current speed, and the first vehicle demand power, the first target slope threshold is obtained.

3. The shift control method of a dual-motor-drive two-axle pure electric commercial vehicle according to claim 2, characterized in that, The calculation formula of the first target slope threshold value is as follows: P1=(mgf+C D Au 2 / 21.15+mgi0)u / 3600 Wherein, m is the total mass of the vehicle, g is the gravity acceleration constant, f is the wheel rolling resistance coefficient, C D is the wind resistance coefficient of the vehicle, A is the windward area of the vehicle, u is the current vehicle speed, i0 is the first target slope threshold, P1 is the first vehicle demand power.

4. The shift control method of a dual-motor-drive two-axle pure electric commercial vehicle according to claim 1, characterized in that, The second target slope threshold is determined based on the following steps: acquiring the total mass of the vehicle, the wheel rolling resistance coefficient, the vehicle wind resistance coefficient, the vehicle frontal area, the current speed, and the second vehicle demand power when the vehicle drives on a road with a slope of the second target slope threshold; based on the total mass of the vehicle, the wheel rolling resistance coefficient, the vehicle wind resistance coefficient, the vehicle frontal area, the current speed, and the second vehicle demand power, the second target slope threshold is obtained.

5. The shift control method of a dual-motor-drive two-axle pure electric commercial vehicle according to claim 4, characterized in that, The calculation formula of the second target slope threshold value is as follows: P2=(mgf+C D Au 2 / 21.15+mgi1)u / 3600 Wherein, m is the total mass of the vehicle, g is the gravity acceleration constant, f is the wheel rolling resistance coefficient, C D is the total vehicle wind resistance coefficient, A is the total vehicle wind area, u is the current vehicle speed, i1 is the second target slope threshold, P2 is the second total vehicle demand power.

6. The shift control method of a dual-motor-drive two-axle pure electric commercial vehicle according to claim 1, characterized in that, The first target gear is obtained based on the following steps: acquiring the current speed of the vehicle, the motor speed, and the wheel radius; determining the target transmission speed ratio based on the product of the motor speed and the wheel radius being at the current speed; based on the target transmission speed ratio, determining the first target gear.

7. The shift control method of the dual-motor-drive two-motor-drive pure electric commercial vehicle according to any one of claims 1-6, characterized in that, The method further comprises: when it is determined based on the vehicle map that there is a downhill in front of the vehicle or that there is an obstructive vehicle in front of the vehicle, controlling the drive axle that has been in neutral to be in the second target gear.

8. The shift control method of a dual-motor-drive two-axle pure electric commercial vehicle according to claim 7, characterized in that, Determining that there is a downhill in front of the vehicle based on the vehicle map comprises: acquiring the slope within the first target distance in front of the vehicle from the vehicle map; determining the vehicle regenerative braking power required to maintain the current speed when the vehicle drives on a downhill road; based on the vehicle regenerative braking power, the total mass of the vehicle, the gravitational acceleration constant, the wheel rolling resistance coefficient, the vehicle wind resistance coefficient, the vehicle frontal area, and the current speed, determining the downhill target slope; when the slope within the first target distance in front of the vehicle is greater than the downhill target slope, determining that there is a downhill in front of the vehicle.

9. The shift control method of a dual-motor-drive two-motor-drive pure electric commercial vehicle according to claim 7, characterized in that, Determining that there is an obstructive vehicle in front of the vehicle based on the vehicle map comprises: acquiring the speed of the vehicle closest to the vehicle in front of the vehicle from the vehicle map; when it is determined that the speed of the vehicle closest to the vehicle in front of the vehicle is less than the target speed threshold, determining that there is an obstructive vehicle in front of the vehicle.

10. A shift control device of a dual-motor-drive-bridge pure electric commercial vehicle, characterized in that, The method comprises: The data acquisition module is configured to acquire a current demand of the vehicle power of the driver, a driving map, and front vehicle data of the vehicle; The first control module of the double electric drive axle is configured to, in the case that the current demand of the vehicle power of the driver is less than the target power threshold, the gradient of the uphill and downhill in the driving map is less than the first target gradient threshold, and it is determined based on the front vehicle data that there is no obstructive vehicle in front of the vehicle, control one of the double electric drive axles to engage the neutral gear, control the drive chain between the double electric drive axles to be disconnected, and control the other drive axle to drive and recover energy; The second control module of the double electric drive axle is configured to, in the case that it is determined based on the driving map that there is an uphill in front of the vehicle and the gradient of the uphill is greater than the second target gradient threshold, control the drive axle that has engaged the neutral gear to engage the first target gear before the vehicle climbs uphill.

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