A slope-based torque control method for an in-wheel motor vehicle and electronic equipment

Abstract

The application discloses a slope-based torque control method for an in-wheel motor automobile and electronic equipment, and the method comprises the following steps: acquiring a vehicle acceleration sensor measurement value and an acceleration obtained through a vehicle speed to determine a slope of a road surface; based on the slope of the road surface, a one-time distribution coefficient of front and rear axle torques is determined by using a multi-section linear relationship, and a total vehicle torque is obtained to determine one-time distribution target torques of the front and rear axles; wheel hub motor speeds of the vehicle are obtained to determine a difference between front and rear axle speeds, and then a front and rear axle torque change flag bit is determined, and a front and rear axle basic lock-up torque is determined; a front and rear axle torque change amount in a single period is determined, and a total front and rear axle torque change amount is determined; based on the total front and rear axle torque change amount and the front and rear axle basic lock-up torque, a front and rear axle secondary distribution target torque is determined, based on the one-time distribution target torques of the front and rear axles and the front and rear axle secondary distribution target torque, a front and rear axle target execution torque is determined, and an execution target torque of each wheel hub motor is determined.

Description

Technical Field

[0001] This invention relates to the field of hub motor vehicle technology, specifically to a torque control method and electronic device for hub motor vehicles based on ramps. Background Technology

[0002] In-wheel motor vehicles offer independent torque control for each wheel, improving vehicle control flexibility and maneuverability, but also increasing the complexity of the overall vehicle control strategy. During operation, the random changes in road slopes cause axle load transfer, resulting in significant variations in the driving capacity of the front and rear axles. This is especially true when climbing steep inclines, where the axle load transfer is extreme, leading to one axle having extremely high driving capacity while the other has very low driving capacity. If the torque of the front and rear axles cannot be dynamically adjusted in real-time according to the slope and axle speed, wheel slippage may occur, potentially causing vehicle instability and safety issues. Summary of the Invention

[0003] The purpose of this invention is to overcome the above-mentioned technical deficiencies and provide a wheel hub motor-based automobile torque control method and electronic device based on ramps, thereby solving the technical problem of vehicle instability during ramp driving in the prior art.

[0004] To achieve the above-mentioned technical objectives, the present invention adopts the following technical solution:

[0005] In a first aspect, the present invention provides a method for controlling the torque of a hub motor vehicle based on a ramp, comprising the following steps:

[0006] The slope of the road surface is determined by acquiring vehicle acceleration sensor measurements and acceleration obtained from the vehicle speed.

[0007] Based on the slope of the road surface, a multi-segment linear relationship is used to determine the first-order distribution coefficient of the front and rear axle torques, and the total torque of the vehicle is obtained. Based on the first-order distribution coefficient of the torques and the total torque, the target torque for the first-order distribution of the front and rear axles is determined.

[0008] The rotational speeds of the left front, left rear, right front, and right rear hub motors are obtained respectively to determine the difference in rotational speed between the front and rear axles. Based on the difference in rotational speed, the torque change flag of the front and rear axles is determined. Based on the torque change flag, the basic locking torque of the front and rear axles is determined.

[0009] Based on the difference in rotational speed, the change in torque between the front and rear axles within a single cycle is determined. Based on the torque change flag and the change in torque between the front and rear axles within a single cycle, the total change in torque between the front and rear axles is determined.

[0010] Based on the total torque change and the base lock-up torque, the target torque for the secondary distribution of the front and rear axles is determined. Based on the target torque for the primary distribution and the target torque for the secondary distribution, the target execution torque for the front and rear axles is determined.

[0011] Based on the target execution torque, the target execution torques of the left front hub motor, the left rear hub motor, the right front hub motor, and the right rear hub motor are determined.

[0012] In some embodiments, the slope of the road surface is calculated as follows:

[0013]

[0014] Where a is the value measured by the accelerometer, a0 is the acceleration obtained by the vehicle speed, g is the gravitational acceleration, and θ is the slope of the road surface where the vehicle is located.

[0015] In some embodiments, the formula for calculating the primary distribution coefficient of the front and rear axle torques is:

[0016]

[0017] Where k is the primary distribution coefficient of the front and rear axle torque, θ0 is the dynamic change threshold of the front and rear axle torque distribution coefficient, θ1 is the maximum gradeability set by the vehicle, θ2 is the maximum descent degree of the vehicle, k1 is the primary distribution coefficient corresponding to the maximum gradeability set by the vehicle, and k2 is the primary distribution coefficient corresponding to the maximum descent degree of the vehicle.

[0018] The formula for calculating the target torque distribution between the front and rear axles is as follows:

[0019]

[0020] Among them, T all T represents the total torque of the vehicle. r Distribute the target torque to the front axle in one step, T f Distribute the target torque to the rear axle in one step.

[0021] In some embodiments, the difference in rotational speed between the front and rear axles is calculated as follows:

[0022] ΔW=max(W fr W fl )-max(W rr W rl ),

[0023] Among them, W fr The speed of the right front wheel hub motor, W fl The speed of the left front wheel hub motor, W rr The speed of the right rear wheel hub motor, Wrl ΔW represents the speed of the left rear wheel hub motor, and ΔW represents the difference in speed between the front and rear axles.

[0024] In some embodiments, the formula for calculating the front and rear axle torque variation flag is:

[0025]

[0026] 0<ΔW4<ΔW3<ΔW2<ΔW1,

[0027] Among them, f f This is the front axle torque variation flag, f r The following are the flags for changes in rear axle torque: ΔW1 is the speed difference threshold for torque reduction, ΔW2 is the upper limit of the speed difference for constant torque, ΔW3 is the lower limit of the speed difference for constant torque, and ΔW4 is the speed difference threshold for torque increase.

[0028] In some embodiments, the formula for calculating the base locking torque of the front and rear axles is:

[0029]

[0030] Among them, T1 r For the front axle base lock-up torque, T1 f This is the base locking torque for the rear axle.

[0031] In some embodiments, the formula for calculating the change in front and rear axle torque within a single cycle is:

[0032]

[0033] ΔT b1 >ΔT b2 >0,

[0034] ΔW 11 >ΔW 12 >0,

[0035] Where, ΔT f ΔT represents the change in front axle torque within a single cycle. r The change in rear axle torque within a single cycle, ΔT b1 ΔT represents the upper limit of the shaft torque variation within a single cycle. b2 ΔW is the lower limit of the shaft torque variation within a single cycle. 11 The speed difference setting value corresponding to the upper limit of the shaft torque change within a single cycle, ΔW 12 The speed difference setting value corresponding to the lower limit of the shaft torque change within a single cycle;

[0036] The formula for calculating the total change in torque between the front and rear axles is:

[0037]

[0038] Wherein, ΔT1 f ΔT1 represents the total change in front axle torque. r The total change in rear axle torque is ΔT1_last. f ΔT1_last represents the value of the total change in front axle torque at the previous moment. r This represents the value of the total change in rear axle torque at the previous moment.

[0039] In some embodiments, the formula for calculating the target torque secondary distribution between the front and rear axles is:

[0040]

[0041] Among them, T2 f To distribute the target torque to the front axle, T2 r The target torque is distributed to the rear axle in a secondary manner;

[0042] The formula for calculating the target torque of the front and rear axles is:

[0043]

[0044] Among them, T3 f T3 is the target torque for the front axle. r The target torque is applied to the rear axle.

[0045] In some embodiments, the target torque for the left rear wheel hub motor, the target torque for the right rear wheel hub motor, the target torque for the left front wheel hub motor, and the target torque for the right front wheel hub motor are calculated as follows:

[0046]

[0047] Among them, T3 rl T3 is the target torque for the left rear wheel hub motor. rr T3 is the target torque for the right rear wheel hub motor. fl T3 is the target torque for the left front wheel hub motor. fr The target torque for the right front wheel hub motor.

[0048] In a second aspect, the present invention also provides an electronic device, comprising: a processor and a memory;

[0049] The memory stores a computer-readable program that can be executed by the processor;

[0050] When the processor executes the computer-readable program, it implements the steps in the ramp-based hub motor vehicle torque control method as described above.

[0051] Compared with existing technologies, the in-wheel motor torque control method and electronic device based on ramp provided by this invention can achieve primary distribution of front and rear axle torque by adjusting the ramp slope when the total vehicle torque is within a certain range. This directly synchronizes the front and rear axle speeds and avoids wheel slippage caused by axle load transfer. When the total vehicle torque exceeds a certain range, the basic locking torque of the front and rear axles is locked again by identifying the difference in front axle speeds. A secondary distribution of torque adjustment is then performed on the basic locking torque to ensure that the difference in front and rear axle speeds does not become too large, thus preventing wheel slippage and ensuring the vehicle's driving stability during steep inclines, thereby improving vehicle safety. Attached Figure Description

[0052] Figure 1 This is a flowchart of an embodiment of the wheel hub motor-based automobile torque control method based on a ramp provided by the present invention;

[0053] Figure 2 This is a flowchart of an embodiment of the wheel hub motor automobile torque control device based on a ramp provided by the present invention;

[0054] Figure 3 This is a schematic diagram of the operating environment of an embodiment of the wheel hub motor automobile torque control program based on a ramp provided by the present invention. Detailed Implementation

[0055] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0056] This invention provides a method and electronic device for torque control of a hub motor in a vehicle based on a ramp, which can be used in a computer. The method, device, or computer-readable storage medium involved in this invention can be integrated with the aforementioned device or be relatively independent.

[0057] This invention provides a method for controlling the torque of a hub motor in a vehicle based on a ramp. Figure 1 This is a flowchart of the wheel hub motor-based vehicle torque control method based on a ramp, provided in an embodiment of the present invention. Please refer to [link / reference]. Figure 1 The in-wheel motor torque control method for automobiles based on ramps includes the following steps:

[0058] S100: Acquire vehicle acceleration sensor measurements and acceleration obtained from vehicle speed to determine road slope;

[0059] S200: Based on the road slope, a multi-segment linear relationship is used to determine the first-order torque distribution coefficient between the front and rear axles, and the total torque of the vehicle is obtained. Based on the first-order torque distribution coefficient and the total torque, the target torque for the first-order distribution between the front and rear axles is determined.

[0060] S300: Obtain the speeds of the left front, left rear, right front, and right rear hub motors respectively to determine the difference between the front and rear axle speeds. Based on the speed difference, determine the front and rear axle torque change flags. Based on the torque change flags, determine the front and rear axle base lock-up torques.

[0061] S400. Based on the difference in rotational speed, determine the change in torque between the front and rear axles within a single cycle. Based on the torque change flag and the change in torque between the front and rear axles within a single cycle, determine the total change in torque between the front and rear axles.

[0062] S500: Based on the total torque change and the basic lock-up torque, determine the secondary distribution target torque of the front and rear axles; based on the primary distribution target torque and the secondary distribution target torque, determine the target execution torque of the front and rear axles.

[0063] S600. Based on the target execution torque, determine the execution target torque of the left front wheel hub motor, the left rear wheel hub motor, the right front wheel hub motor, and the right rear wheel hub motor.

[0064] In this embodiment, the vehicle acceleration sensor measurement value and the acceleration obtained through the vehicle speed are acquired to determine the road surface slope. Based on the road surface slope, a multi-segment linear relationship is used to determine the primary torque distribution coefficient between the front and rear axles, and the total torque of the vehicle is obtained. Based on the primary torque distribution coefficient and the total torque, the primary distribution target torque of the front and rear axles is determined. The vehicle hub motor speeds are acquired separately, and after determining the difference between the front and rear axle speeds, the front and rear axle torque change flags are determined, and the basic locking torque of the front and rear axles is determined. The change in front and rear axle torque within a single cycle is determined, and the total change in front and rear axle torque is determined. Based on the total change in front and rear axle torque and the basic locking torque of the front and rear axles, the secondary distribution target torque of the front and rear axles is determined. Based on the primary distribution target torque and the secondary distribution target torque, the target execution torque of the front and rear axles is determined. By determining the execution target torque of each hub motor, the vehicle safety is improved.

[0065] In some embodiments, in step S100, the vehicle acceleration sensor measurement value is obtained, the vehicle speed is obtained, the acceleration is obtained based on the vehicle speed, and the slope of the road surface where the vehicle is located is determined based on the acceleration sensor measurement value and the acceleration. The slope is equal to the arcsine of the quotient of the difference between the acceleration sensor measurement value and the acceleration obtained through the vehicle speed and the gravitational acceleration. The formula for calculating the slope of the road surface where the vehicle is located is:

[0066]

[0067] Where a is the value measured by the accelerometer, a0 is the acceleration obtained from the vehicle speed, g is the gravitational acceleration, θ is the slope of the road surface where the vehicle is located, and the acceleration a0 is the derivative of the vehicle speed v, which is calculated as follows:

[0068]

[0069] When the vehicle speed is low, the acceleration obtained from the vehicle speed can be directly taken as 0, then the formula for calculating the road slope is:

[0070]

[0071] Where θ is the slope of the road surface where the vehicle is located, a is the value measured by the acceleration sensor, and g is the gravitational acceleration.

[0072] In some embodiments, in step S200, since the vehicle is on a slope, there is a transfer of axle load, and the driving capacity of the front and rear axles changes. In order to maximize the driving capacity of the wheels with larger axle loads while reducing the slippage tendency of the wheels with smaller axle loads, a multi-segment linear relationship is used to determine the primary distribution coefficient of the front and rear axle torque based on the slope of the road surface where the vehicle is located. The formula for calculating the primary distribution coefficient of the front and rear axle torque is as follows:

[0073]

[0074] Where k is the primary distribution coefficient of the front and rear axle torque, θ0 is the dynamic change threshold of the front and rear axle torque distribution coefficient, θ1 is the maximum gradeability set by the vehicle, θ2 is the maximum descent degree of the vehicle, k1 is the primary distribution coefficient corresponding to the maximum gradeability set by the vehicle, and k2 is the primary distribution coefficient corresponding to the maximum descent degree of the vehicle.

[0075] When the road surface slope is small, the primary distribution coefficient of the front and rear axle torque is 1. When the road surface slope is large, the primary distribution coefficient of the front and rear axle torque is linearly related to the road surface slope.

[0076] In some embodiments, the total vehicle torque is obtained, and based on the primary distribution coefficient of the front and rear axle torques and the total vehicle torque, the target torque for primary distribution of the front and rear axles is determined. That is, the total vehicle torque is distributed to the front and rear axles according to the primary distribution coefficient of the front and rear axle torques. The calculation formula for the target torque for primary distribution of the front and rear axles is as follows:

[0077]

[0078] Among them, T all T represents the total torque of the vehicle. r Distribute the target torque to the front axle in one step, T f Distribute the target torque to the rear axle in one step.

[0079] In some embodiments, in step S300, the rotational speeds of the left front, left rear, right front, and right rear wheel hub motors are obtained respectively. The difference between the front and rear axle rotational speeds is determined by the difference between the larger of the right front wheel hub motor rotational speed and the left front wheel hub motor rotational speed and the larger of the left rear wheel hub motor rotational speed and the right rear wheel hub motor rotational speed. The formula for calculating the difference between the front and rear axle rotational speeds is as follows:

[0080] ΔW=max(W fr W fl )-max(W rr W rl ),

[0081] Among them, W fr The speed of the right front wheel hub motor, W fl The speed of the left front wheel hub motor, W rr The speed of the right rear wheel hub motor, W rl ΔW represents the speed of the left rear wheel hub motor, and ΔW represents the difference in speed between the front and rear axles.

[0082] In some embodiments, a speed difference threshold for torque reduction, an upper limit for torque-constant speed difference, a lower limit for torque-constant speed difference, and a speed difference threshold for torque increase are set. Based on the relationship between these thresholds and the differences in speed between the front and rear axles, a flag bit for torque change between the front and rear axles is set. The formula for calculating this flag bit is as follows:

[0083]

[0084] 0<ΔW4<ΔW3<ΔW2<ΔW1,

[0085] Among them, f f This is the front axle torque variation flag, f r The rear axle torque change flag is set as follows: ΔW1 is the speed difference threshold for torque reduction, ΔW2 is the upper limit of the speed difference for constant torque, ΔW3 is the lower limit of the speed difference for constant torque, and ΔW4 is the speed difference threshold for torque increase.

[0086] When the difference between the front and rear axle speeds is greater than or equal to the speed difference threshold for torque reduction, the front axle torque change flag is -1; when the difference between the front and rear axle speeds is greater than or equal to the lower limit of the speed difference for constant torque and less than or equal to the upper limit of the speed difference for constant torque, the front axle torque change flag is 0; when the difference between the front and rear axle speeds is less than or equal to the speed difference threshold for torque increase, the front axle torque change flag is 1.

[0087] When the difference between the current and rear axle speeds is less than or equal to the opposite of the speed difference threshold for torque reduction, the rear axle torque change flag is -1; when the difference between the current and rear axle speeds is greater than or equal to the opposite of the lower limit of the speed difference threshold for constant torque and less than or equal to the opposite of the upper limit of the speed difference threshold for constant torque, the rear axle torque change flag is 0; when the difference between the current and rear axle speeds is greater than or equal to the opposite of the speed difference threshold for torque increase, the rear axle torque change flag is 1.

[0088] In some embodiments, to prevent changes in the total vehicle torque during dynamic torque adjustment from causing changes in the base lock-up torque of the front and rear axles, the base lock-up torque of the front and rear axles is set based on the status of the front and rear axle torque change flags. When the front axle torque change flag is 1, the front axle base lock-up torque is dynamically equal to the target torque of the front axle primary distribution. When the front axle torque change flag is -1 or 0, the front axle base lock-up torque remains unchanged, and locking is performed. When the rear axle torque change flag is 1, the rear axle base lock-up torque is dynamically equal to the target torque of the rear axle primary distribution. When the rear axle torque change flag is -1 or 0, the rear axle base lock-up torque remains unchanged, and locking is performed. The calculation formula for the base lock-up torque of the front and rear axles is as follows:

[0089]

[0090] Among them, T1 r For the front axle base lock-up torque, T1 f This is the base locking torque for the rear axle.

[0091] In some embodiments, in step S400, to achieve rapid torque adjustment, the larger the speed difference, the faster the torque change should be adjusted. Therefore, a lower limit value for the shaft torque change within a single cycle and a corresponding speed difference setting value are set, as are an upper limit value for the shaft torque change within a single cycle and a corresponding speed difference setting value. The change in front and rear shaft torque within a single cycle is set based on the difference in front and rear shaft speeds. The formula for calculating the change in front and rear shaft torque within a single cycle is as follows:

[0092]

[0093] ΔT b1 >ΔT b2 >0,

[0094] ΔW 11 >ΔW 12 >0,

[0095] Where, ΔT f ΔT represents the change in front axle torque within a single cycle. r The change in rear axle torque within a single cycle, ΔT b1 ΔT represents the upper limit of the shaft torque variation within a single cycle. b2ΔW is the lower limit of the shaft torque variation within a single cycle. 11 The speed difference setting value corresponding to the upper limit of the shaft torque change within a single cycle, ΔW 12 This is the speed difference setting value corresponding to the lower limit of the shaft torque change within a single cycle.

[0096] In some embodiments, the total change in front and rear axle torque is determined based on the front and rear axle torque change flags and the change in front and rear axle torque within a single cycle. The formula for calculating the total change in front and rear axle torque is as follows:

[0097]

[0098] Wherein, ΔT1 f ΔT1 represents the total change in front axle torque. r The total change in rear axle torque is ΔT1_last. f ΔT1_last represents the value of the total change in front axle torque at the previous moment. r The value of the total change in rear axle torque at the previous moment, ΔT1_last at its initial moment. f ΔT1_last r All values ​​are 0.

[0099] In some embodiments, in step S500, based on the total change in torque between the front and rear axles and the basic locking torque of the front and rear axles, the target torque for secondary distribution of the front and rear axles is determined. The target torque for secondary distribution of the front axle is the sum of the total change in torque between the front axle and the basic locking torque of the front axle, and the target torque for secondary distribution of the rear axle is the sum of the total change in torque between the rear axle and the basic locking torque of the rear axle. The calculation formula for the target torque for secondary distribution of the front and rear axles is as follows:

[0100]

[0101] Among them, T2 f To distribute the target torque to the front axle, T2 r Distribute the target torque to the rear axle in a secondary manner; T2 f and T2 r It represents the maximum driving force that the road surface can provide.

[0102] In some embodiments, the front and rear axle target execution torques are calculated to ensure that when the total vehicle torque decreases, the front and rear axle target execution torques decrease synchronously, and when the total vehicle torque increases, the front and rear axle target execution torques do not exceed the anti-slip effect of the secondary distribution target torque of the front and rear axles. Based on the secondary distribution target torques and the primary distribution target torques of the front and rear axles, the front and rear axle target execution torques are determined. The formula for calculating the front and rear axle target execution torques is as follows:

[0103]

[0104] Among them, T3f T3 is the target torque for the front axle. r The target torque is applied to the rear axle.

[0105] In some embodiments, in step S600, based on the target execution torque of the front and rear axles, the target execution torque of each hub motor is determined. The target execution torque of each hub motor is equal to half of its axle target execution torque, ensuring that the speed difference between the front and rear axles does not differ significantly, thereby preventing wheel slippage. The calculation formulas for the target execution torques of the left front hub motor, right front hub motor, left rear hub motor, and right rear hub motor are as follows:

[0106]

[0107] Among them, T3 fl The target torque for the left front wheel hub motor; T3 fr T3 is the target torque for the right front wheel hub motor. rl The target torque for the left rear wheel hub motor; T3 rr The target torque for the right rear wheel hub motor.

[0108] The present invention also provides a corresponding torque control device for a wheel hub motor vehicle based on a ramp. (See attached description of the method for torque control of a wheel hub motor vehicle based on a ramp.) Figure 2 The ramp-based hub motor vehicle torque control device 700 includes a ramp determination module 710, a primary distribution target torque determination module 720, a basic lock-up torque determination module 730, a total torque change determination module 740, a front and rear axle target execution torque module 750, and a hub motor execution target torque determination module 760.

[0109] The slope determination module 710 is used to acquire the measurement values ​​of the vehicle acceleration sensor and the acceleration obtained through the vehicle speed in order to determine the slope of the road surface.

[0110] The primary distribution target torque determination module 720 is used to determine the primary distribution coefficient of the front and rear axle torques based on the road slope using a multi-segment linear relationship, obtain the total torque of the vehicle, and determine the primary distribution target torque of the front and rear axles based on the primary distribution coefficient of the torques and the total torque.

[0111] The basic lock-up torque determination module 730 is used to obtain the speeds of the left front, left rear, right front, and right rear hub motors respectively, to determine the difference between the front and rear axle speeds, to determine the front and rear axle torque change flags based on the speed difference, and to determine the front and rear axle basic lock-up torque based on the torque change flags.

[0112] The total torque change determination module 740 is used to determine the change in front and rear axle torque within a single cycle based on the difference in rotational speed, and to determine the total change in front and rear axle torque based on the torque change flag and the change in front and rear axle torque within a single cycle.

[0113] The front and rear axle target execution torque determination module 750 is used to determine the secondary distribution target torque of the front and rear axles based on the total torque change and the basic lock-up torque, and to determine the front and rear axle target execution torque based on the primary distribution target torque and the secondary distribution target torque.

[0114] The hub motor execution target torque determination module 760 is used to determine the execution target torque of the left front hub motor, the left rear hub motor, the right front hub motor, and the right rear hub motor based on the target execution torque.

[0115] like Figure 3 As shown in the diagram, this invention also provides an electronic device for the in-wheel motor torque control method for automobiles based on ramps. This electronic device can be a mobile terminal, desktop computer, laptop, handheld computer, or server, among other computing devices. The electronic device includes a processor 10, a memory 20, and a display 30. Figure 3 Only some components of the electronic device are shown; however, it should be understood that it is not required to implement all of the components shown, and more or fewer components may be implemented instead.

[0116] In some embodiments, memory 20 may be an internal storage unit of the electronic device, such as a hard disk or RAM. In other embodiments, memory 20 may be an external storage device of the electronic device, such as a plug-in hard disk, smart media card (SMC), secure digital card (SD), flash card, etc. Furthermore, memory 20 may include both internal and external storage units. Memory 20 is used to store application software and various types of data installed on the electronic device, such as program code installed on the electronic device. Memory 20 may also be used to temporarily store data that has been output or will be output. In one embodiment, memory 20 stores a ramp-based hub motor vehicle torque control program 40, which can be executed by processor 10 to implement the ramp-based hub motor vehicle torque control method of the various embodiments of the present invention.

[0117] In some embodiments, processor 10 may be a central processing unit (CPU), microprocessor or other data processing chip, used to run program code stored in memory 20 or process data, such as a wheel hub motor torque control method based on ramps.

[0118] In some embodiments, display 30 may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen. Display 30 is used to display information regarding the torque control of the ramp-based hub motor vehicle and to display a visual user interface. Components 10-30 of the electronic device communicate with each other via a system bus.

[0119] In some embodiments, when the processor 10 executes the ramp-based hub motor vehicle torque control program 40 in the memory 20, it implements the various steps in the ramp-based hub motor vehicle torque control method as described in the above embodiments. Since the ramp-based hub motor vehicle torque control method has been described in detail above, it will not be repeated here.

[0120] In summary, the in-wheel motor torque control method and electronic device for automobiles based on slope provided by this invention first acquires the vehicle acceleration sensor measurement value and the acceleration obtained through the vehicle speed to determine the road slope; based on the road slope, a multi-segment linear relationship is used to determine the primary distribution coefficient of the front and rear axle torque; secondly, the total torque of the entire vehicle is acquired, and based on the primary distribution coefficient of the torque and the total torque, the primary distribution target torque of the front and rear axles is determined; the speed of the vehicle's in-wheel motors is acquired separately, and after determining the difference between the speeds of the front and rear axles, the torque change flags of the front and rear axles are determined, and the basic locking torque of the front and rear axles is determined; the torque change of the front and rear axles within a single cycle is determined, and the total torque change of the front and rear axles is determined; based on the total torque change of the front and rear axles and the basic locking torque of the front and rear axles, the secondary distribution target torque of the front and rear axles is determined; finally, based on the primary distribution target torque and the secondary distribution target torque, the target execution torque of the front and rear axles is determined; thus, the execution target torque of each in-wheel motor is determined, improving vehicle safety.

[0121] Of course, those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware (such as a processor, controller, etc.). The program can be stored in a computer-readable storage medium, and when executed, it can include the processes described in the above method embodiments. The storage medium can be a memory, magnetic disk, optical disk, etc.

[0122] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for controlling the torque of a hub motor in a vehicle based on a ramp, characterized in that, Includes the following steps: The slope of the road surface is determined by acquiring vehicle acceleration sensor measurements and acceleration obtained from the vehicle speed. Based on the road surface slope, a multi-segment linear relationship is used to determine the primary torque distribution coefficient between the front and rear axles, thereby obtaining the total vehicle torque. Based on the primary torque distribution coefficient and the total torque, the target torque for primary torque distribution between the front and rear axles is determined. The road surface slope is calculated using the following formula: ， in, The values ​​are measured by the accelerometer. The acceleration obtained from the vehicle speed. It is the acceleration due to gravity. The slope of the road surface where the vehicle is located; The formula for calculating the primary distribution coefficient of the front and rear axle torque is: ， in, This is the primary torque distribution coefficient between the front and rear axles. The threshold for dynamic change of the front and rear axle torque distribution coefficient. The maximum gradeability set for the vehicle. This represents the maximum angle at which the vehicle can descend a slope. The primary distribution coefficient corresponding to the maximum gradeability set for the vehicle. This is the primary distribution coefficient corresponding to the maximum gradient of the downhill slope for the vehicle. The formula for calculating the target torque distribution between the front and rear axles is as follows: ， in, This represents the total torque of the vehicle. Distribute the target torque to the front axle in one step. Distribute the target torque to the rear axle in one step; The rotational speeds of the left front, left rear, right front, and right rear hub motors are acquired respectively to determine the difference in rotational speed between the front and rear axles. Based on the difference in rotational speed, a torque change flag is determined for the front and rear axles. Based on the torque change flag, the base lock-up torque for the front and rear axles is determined. Specifically, when the front axle torque change flag is 1, the base lock-up torque of the front axle is dynamically equal to the target torque allocated to the front axle in real time; when the front axle torque change flag is -1 or 0, the base lock-up torque of the front axle remains unchanged, and locking is performed. When the rear axle torque change flag is 1, the base lock-up torque of the rear axle is dynamically equal to the target torque allocated to the rear axle in real time; when the rear axle torque change flag is -1 or 0, the base lock-up torque of the rear axle remains unchanged, and locking is performed. Based on the difference in rotational speed, the change in torque between the front and rear axles within a single cycle is determined. Based on the torque change flag and the change in torque between the front and rear axles within a single cycle, the total change in torque between the front and rear axles is determined. Based on the total torque change and the base lock-up torque, the target torque for the secondary distribution of the front and rear axles is determined. Based on the target torque for the primary distribution and the target torque for the secondary distribution, the target execution torque for the front and rear axles is determined. Based on the target execution torque, the target execution torques of the left front hub motor, the left rear hub motor, the right front hub motor, and the right rear hub motor are determined.

2. The wheel hub motor torque control method for automobiles based on ramps according to claim 1, characterized in that, The formula for calculating the difference in rotational speed between the front and rear axles is: ， in, This refers to the rotational speed of the right front wheel hub motor. This refers to the rotational speed of the left front wheel hub motor. This refers to the rotational speed of the right rear wheel hub motor. This refers to the speed of the left rear wheel hub motor. This represents the difference in rotational speed between the front and rear axles.

3. The wheel hub motor torque control method for automobiles based on ramps according to claim 2, characterized in that, The formula for calculating the front and rear axle torque variation flags is: ， ， in, This is a flag indicating changes in front axle torque. This is a flag indicating the change in rear axle torque. The speed difference threshold is the torque minus the speed difference. This represents the upper limit of the speed difference while maintaining constant torque. This represents the lower limit of the speed difference while maintaining constant torque. The speed difference threshold for torque increase.

4. The wheel hub motor-based automobile torque control method according to claim 3, characterized in that, The formula for calculating the base locking torque of the front and rear axles is: ， in, For the front axle base lock-up torque, This is the base locking torque for the rear axle.

5. The wheel hub motor torque control method for automobiles based on ramps according to claim 4, characterized in that, The formula for calculating the change in front and rear axle torque within a single cycle is: ， ， ， in, This represents the change in front axle torque within a single cycle. This represents the change in rear axle torque within a single cycle. This represents the upper limit of the shaft torque variation within a single cycle. This represents the lower limit of the shaft torque variation within a single cycle. This is the speed difference setting value corresponding to the upper limit of the shaft torque change within a single cycle. The speed difference setting value corresponding to the lower limit of the shaft torque change within a single cycle; The formula for calculating the total change in torque between the front and rear axles is: ， in, This represents the total change in front axle torque. This represents the total change in rear axle torque. This represents the value of the total change in front axle torque at the previous moment. This represents the value of the total change in rear axle torque at the previous moment.

6. The wheel hub motor torque control method for automobiles based on ramps according to claim 5, characterized in that, The formula for calculating the target torque for secondary distribution between the front and rear axles is: ， in, The target torque is distributed to the front axle in a secondary manner. The target torque is distributed to the rear axle in a secondary manner; The formula for calculating the target torque of the front and rear axles is: ， in, The target torque for the front axle is... The target torque is applied to the rear axle.

7. The wheel hub motor-based vehicle torque control method according to claim 6, characterized in that, The target torques for the left rear wheel hub motor, right rear wheel hub motor, left front wheel hub motor, and right front wheel hub motor are calculated using the following formulas: ， in, The target torque for the left rear wheel hub motor is... The target torque for the right rear wheel hub motor is... The target torque for the left front wheel hub motor is... The target torque for the right front wheel hub motor.

8. An electronic device, characterized in that, include: Processor and memory; The memory stores a computer-readable program that can be executed by the processor; When the processor executes the computer-readable program, it implements the steps in the wheel hub motor torque control method for automobiles based on ramps as described in any one of claims 1-7.

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