A method for detecting effective axles and power distribution of a pure electric distributed multi-axle vehicle

Abstract

The present invention discloses a method for detecting effective axles and power distribution of a pure electric distributed multi-axle vehicle, including step 1: selecting a distribution mode according to the vehicle speed; step 2: detecting effective axles; determining whether each wheel is in an excluded state. If it is not in an excluded state, go to step 3; if it is in an excluded state, go to step 4; step 3: driving force distribution. In the all-wheel drive mode, the driver's required torque is evenly distributed to all wheels. In the free distribution mode, according to the magnitude of the driver's required torque and the number of selected drive axles, the driving force is distributed; step 4: suspension wheel and ineffective axle restoration torque limit algorithm. In the free distribution mode, power is restored to the ineffective axle. In the all-wheel drive mode, power is restored to the suspension wheel.

Description

Technical Field

[0001] The present invention belongs to the field of automotive product research and development, and particularly relates to a method for detecting effective axles and power distribution of a pure electric distributed multi-axle vehicle. Background Art

[0002] With the increasingly severe energy crisis, the development of new energy vehicles has been emphasized by more enterprises and research institutions. Compared with centralized drive vehicles, distributed drive vehicles have the advantages of high drive efficiency, favorable vehicle layout, fast power response, easy implementation of vehicle TCS, ABS, DYC, and ride comfort control, etc., and can achieve electronic differential control through coordinated control of drive / brake of each wheel. For multi-axle vehicles, due to different driving conditions, different required torques are needed. In order to reduce energy waste, the corresponding number of drive wheels can be selected according to the size of the required torque. During actual driving, the state of a wheel being suspended may also occur. After detecting that a wheel is suspended, the torque of the suspended wheel is unloaded and distributed to other wheels, so as to reduce power waste on the premise of unchanged torque response. Summary of the Invention

[0003] The purpose of the present invention is to provide a method for detecting effective axles and power distribution of a pure electric distributed multi-axle vehicle, which is used to solve the problems of power distribution of multi-axle distributed electric vehicles and energy waste when wheels are suspended.

[0004] A method for detecting effective axles and power distribution of a pure electric distributed multi-axle vehicle includes the following steps:

[0005] Step 1: Select a distribution mode according to the vehicle speed.

[0006] When the vehicle speed is greater than the limit value, it is forced to enter the free distribution mode.

[0007] When the vehicle speed is less than or equal to the limit value, the all-wheel drive mode and the free distribution mode can be switched to each other, and the switching between the all-wheel drive mode and the free distribution mode can be carried out through a rocker switch.

[0008] Step 2: Detect effective axles.

[0009] Judge whether each wheel is in the excluded state. If it is not in the excluded state, enter Step 3; if it is in the excluded state, enter Step 4.

[0010] Step 3: Drive force distribution.

[0011] In the all-wheel drive mode, the driver's required torque is evenly distributed to all wheels.

[0012] In the free distribution mode, according to the size of the driver's required torque and the number of selected drive axles, drive force distribution is carried out.

[0013] Step 4: Suspended wheel and invalid axle recovery torque limit algorithm:

[0014] In the free distribution mode, restore power to the invalid bridge.

[0015] In the all-wheel drive mode, restore power to the suspended wheels.

[0016] Furthermore, in step 1, the free mode is to determine the number of drive axles according to the required torque value, and the all-wheel drive mode is to evenly distribute the required torque to all wheels.

[0017] Furthermore, step 2 includes:

[0018] Step 21: Monitor the slip ratio and acceleration of each wheel, and determine whether each wheel is a suspended wheel. If it is a suspended wheel, the axle where the suspended wheel is located is an invalid axle.

[0019] Step 22: In the all-wheel drive mode, exclude the suspended wheels, and distribute the torque of the suspended wheels to other wheels. The suspended wheels are in an excluded state.

[0020] Step 23: In the free distribution mode, exclude the invalid axle, and distribute the torque of the invalid axle to other axles. The invalid axle is in an excluded state.

[0021] Furthermore, in step 21, if the slip ratio of the wheel is greater than the set threshold value, or the acceleration is greater than the set threshold value compared with the vehicle acceleration calculated by the vehicle inertial navigation, it is determined that the wheel is a suspended wheel, otherwise it is not a suspended wheel.

[0022] Furthermore, step 2 also includes: judging whether there is a third-level fault.

[0023] If there is no third-level fault, proceed to step 3.

[0024] If there is a third-level fault:

[0025] In the all-wheel drive mode, exclude the wheel where the third-level fault is located, and distribute the torque of this wheel to other wheels. This wheel is in an excluded state.

[0026] In the free distribution mode, exclude the axle where the third-level fault is located, and distribute the torque of this axle to other axles. This axle is in an excluded state.

[0027] Furthermore, step 3: driving force distribution

[0028] In the all-wheel drive mode, evenly distribute the driver's required torque to all wheels.

[0029] In the free distribution mode, select the number of drive axles for driving force distribution according to the magnitude of the driver's required torque.

[0030] Furthermore, in step 3, the basis for selecting the number of axles is the maximum torque output value of each wheel at the current moment and the driver's required torque value.

[0031] Further, step 4 includes:

[0032] Step 41: In the free distribution mode, after a certain delay, power is restored to the invalid axle. When restoring, the torque recovery value of the invalid axle increases linearly.

[0033] Step 42: In the all-wheel drive mode, after a certain delay, power is restored to the suspended wheels. When restoring, the torque recovery value of the suspended wheels increases linearly.

[0034] In step 41, the initial torque can be the minimum torque value capable of driving the invalid axle to rotate. While increasing the torque of the restored wheel, the torque of other wheels is reduced to keep the total required torque of the driver unchanged.

[0035] In step 42, the initial torque can be the minimum torque value capable of driving the suspended wheels to rotate. While increasing the torque of the restored wheel, the torque of other wheels is reduced to keep the total required torque of the driver unchanged.

[0036] The beneficial effects of the present invention are as follows:

[0037] 1. By monitoring the slip ratio and acceleration of each wheel, the present invention determines the suspension status of each wheel at the current moment. If the slip ratio is greater than the set threshold value or the acceleration differs from the vehicle acceleration calculated by the vehicle inertial navigation by more than the set threshold value, it is determined that the wheel is suspended and it is excluded. At the same time, the torque of this wheel is distributed to other driving wheels to ensure that the required torque of the driver can be fully responded to.

[0038] 2. After a certain delay time after exclusion, the present invention restores the torque of the wheel. When restoring the torque, the torque recovery value of the excluded axle increases linearly. The initial torque value can be set as the minimum torque value capable of driving the suspended wheel to rotate. While increasing the torque of the restored wheel, the torque of other wheels is reduced to keep the total required torque of the driver unchanged.

[0039] 3. The present invention can solve the problems of power distribution and energy waste when the wheels are suspended in a multi-axis distributed electric vehicle through the effective axle detection and power distribution method of a pure electric distributed multi-axis vehicle. Description of the Drawings

[0040] Figure 1 It is the logic flowchart of the present invention. Detailed Embodiments

[0041] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be noted here that the description of these embodiments is for helping to understand the present invention, but does not constitute a limitation on the present invention. The functional details disclosed in the present invention are only used to describe the exemplary embodiments of the present invention. However, the present invention can be embodied in many alternative forms and should not be construed as being limited to the embodiments described in the present invention.

[0042] It should be understood that the terms used in the present invention are only for describing specific embodiments and are not intended to limit the exemplary embodiments of the present invention. When the terms "comprise", "comprises", "include" and / or "includes" are used in the present invention, they specify the existence of the stated features, integers, steps, operations, units and / or components, and do not exclude the existence or addition of one or more other features, quantities, steps, operations, units, components and / or their combinations.

[0043] It should be understood that attention should also be paid to the fact that in some alternative embodiments, the functions / actions that occur may be different from the order shown in the accompanying drawings. For example, depending on the functions / actions involved, they may actually be executed substantially concurrently, or sometimes the two consecutive figures shown may be executed in the reverse order.

[0044] It should be understood that specific details are provided in the following description to facilitate a complete understanding of the exemplary embodiments. However, those of ordinary skill in the art should understand that the exemplary embodiments can be implemented without these specific details. For example, the system can be shown in a block diagram to avoid obscuring the example with unnecessary details. In other instances, well-known processes, structures and technologies can be shown without unnecessary details to avoid obscuring the exemplary embodiments.

[0045] Embodiment 1:

[0046] As Figure 1 shown, a method for detecting effective axles and power distribution of a pure electric distributed multi-axle vehicle includes the following steps:

[0047] Step 1: Select a distribution mode according to the vehicle speed;

[0048] When the vehicle speed is greater than the limit value, forcefully enter the free distribution mode;

[0049] When the vehicle speed is less than or equal to the limit value, the all-wheel drive mode and the free distribution mode can be switched to each other.

[0050] Step 2: Effective axle detection:

[0051] Judge whether each wheel is in the excluded state. If it is not in the excluded state, enter Step 3; if it is in the excluded state, enter Step 4.

[0052] Step 3: Driving force distribution:

[0053] In the all-wheel drive mode, the driver's required torque is evenly distributed to all wheels.

[0054] In the free distribution mode, the driving force is distributed according to the magnitude of the driver's required torque and the number of selected drive axles.

[0055] Step 4: Algorithm for restoring torque limit of suspended wheels and invalid axles:

[0056] In the free distribution mode, power is restored to the invalid axle.

[0057] In the all-wheel drive mode, power is restored to the suspended wheels.

[0058] Embodiment 2:

[0059] An effective axle detection and power distribution method for a pure electric distributed multi-axle vehicle, comprising the following steps:

[0060] Step 1: Select the distribution mode according to the vehicle speed;

[0061] When the vehicle speed is greater than 35 km / h, it is forced to enter the free distribution mode;

[0062] When the vehicle speed is less than or equal to 35 km / h, the all-wheel drive mode and the free distribution mode can be freely switched by the driver through a rocker switch.

[0063] In Step 1, in the free mode, the number of drive axles is determined according to the required torque value, and in the all-wheel drive mode, the required torque is evenly distributed to all wheels.

[0064] Step 2: Effective axle detection:

[0065] Step 21: Monitor the slip ratio and acceleration of each wheel. If the slip ratio of the wheel is greater than 15%, or the acceleration is greater than 20% compared to the vehicle acceleration calculated by the vehicle inertial navigation, determine that the wheel is a suspended wheel, and the axle where the suspended wheel is located is an invalid axle.

[0066] Step 22: In the all-wheel drive mode, the suspended wheels are excluded, and the torque of the suspended wheels is distributed to other wheels, and the suspended wheels are in the excluded state.

[0067] Step 23: In the free distribution mode, the invalid axles are excluded, and the torque of the invalid axles is distributed to other axles, and the invalid axles are in the excluded state.

[0068] Step 4 includes:

[0069] Step 41: In the free distribution mode, after a certain delay, power is restored to the invalid axle. When restoring, the torque recovery value of the invalid axle increases linearly.

[0070] The initial torque can be the minimum torque value capable of driving the invalid axle to rotate. While increasing the torque of the recovery wheel, the torque of other wheels is reduced, keeping the total required torque of the driver unchanged.

[0071] Step 42: In the all-wheel drive mode, after a certain delay, power is restored to the suspended wheels. When restoring, the torque restoration value of the suspended wheels increases linearly.

[0072] The initial torque can be the minimum torque value capable of driving the suspended wheels to rotate. While increasing the torque of the recovery wheel, the torque of other wheels is reduced, keeping the total required torque of the driver unchanged.

[0073] Embodiment 3:

[0074] An effective axle detection and power distribution method for a pure electric distributed multi-axle vehicle, comprising the following steps:

[0075] Step 1: Select a distribution mode according to the vehicle speed;

[0076] When the vehicle speed is greater than the limit value, it is forced to enter the free distribution mode;

[0077] When the vehicle speed is less than or equal to the limit value, the all-wheel drive mode and the free distribution mode can be switched to each other.

[0078] The free mode is to determine the number of drive axles according to the required torque value, and the all-wheel drive mode is to evenly distribute the required torque to all wheels.

[0079] Step 2: Effective axle detection;

[0080] Step 21: Monitor the slip rate and acceleration of each wheel to determine whether each wheel is a suspended wheel. If it is not a suspended wheel, it does not need to be excluded.

[0081] Step 3: Driving force distribution;

[0082] In the all-wheel drive mode, the required torque of the driver is evenly distributed to all wheels.

[0083] In the free distribution mode, according to the magnitude of the required torque of the driver and the selected number of drive axles, the driving force is distributed.

[0084] The basis for selecting the number of axles is the maximum torque output value of each wheel at the current moment and the required torque value of the driver.

[0085] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features. And these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

[0086] The present invention is not limited to the above optional embodiments, and anyone can obtain other various forms of products under the inspiration of the present invention. The above specific embodiments should not be construed as limiting the protection scope of the present invention, and the protection scope of the present invention should be defined by the claims, and the specification can be used to interpret the claims.

Claims

1. A method for detecting effective axles and power distribution of a pure electric distributed multi-axle vehicle, characterized in that: It includes the following steps: Step 1: Select the distribution mode according to the vehicle speed: When the vehicle speed is greater than the limit value, it is forced to enter the free distribution mode; When the vehicle speed is less than or equal to the limit value, the all-wheel drive mode and the free distribution mode can be switched to each other; In Step 1, the free distribution mode is to determine the number of drive axles according to the required torque value, and the all-wheel drive mode is to evenly distribute the required torque to all wheels; Step 2: Effective axle detection: Judge whether each wheel is in the excluded state. If it is not in the excluded state, go to Step 3; if it is in the excluded state, go to Step 4; Specifically, it includes: Step 21: Monitor the slip ratio and acceleration of each wheel, and determine whether each wheel is a suspended wheel. If it is a suspended wheel, the axle where the suspended wheel is located is an ineffective axle; Step 22: In the all-wheel drive mode, exclude the suspended wheels and distribute the torque of the suspended wheels to other wheels. The suspended wheels are in the excluded state; Step 23: In the free distribution mode, exclude the ineffective axles and distribute the torque of the ineffective axles to other axles. The ineffective axles are in the excluded state; Step 3: Driving force distribution: In the all-wheel drive mode, evenly distribute the driver's required torque to all wheels; In the free distribution mode, perform driving force distribution according to the driver's required torque value and the selected number of drive axles; Step 4: Torque limit recovery algorithm for suspended wheels and ineffective axles: In the free distribution mode, restore power to the ineffective axles; In the all-wheel drive mode, restore power to the suspended wheels.

2. The effective bridge detection and power distribution method for a pure electric distributed multi-axle vehicle according to claim 1, characterized in that: In Step 21, if the slip ratio of the wheel is greater than the set threshold value, or the acceleration is greater than the set threshold value compared with the vehicle acceleration calculated by the vehicle inertial navigation, it is determined that the wheel is a suspended wheel; otherwise, it is not a suspended wheel.

3. The effective bridge detection and power distribution method for a pure electric distributed multi-axis vehicle according to claim 1, characterized in that: In Step 3, the basis for selecting the number of drive axles is the maximum torque output value of each wheel at the current moment and the driver's required torque value.

4. The effective bridge detection and power distribution method for a pure electric distributed multi-axle vehicle according to claim 1, characterized in that: Step 4 includes: Step 41: In the free distribution mode, after a certain delay, restore power to the ineffective axles. When restoring, the torque recovery value of the ineffective axles increases linearly; Step 42: In the all-wheel drive mode, after a certain delay, restore power to the suspended wheels. When restoring, the torque recovery value of the suspended wheels increases linearly.

5. The effective axle detection and power distribution method for a pure electric distributed multi-axle vehicle according to claim 4, characterized in that: In Step 41, the initial torque is the minimum torque value that can drive the ineffective axle to rotate. While increasing the torque of the restored wheel, reduce the torque of other wheels to keep the total driver's required torque value unchanged.

6. The method for detecting the effective axle and power distribution of a pure electric distributed multi-axle vehicle according to claim 4, characterized in that: In Step 42, the initial torque is the minimum torque value that can drive the suspended wheel to rotate. While increasing the torque of the restored wheel, reduce the torque of other wheels to keep the total driver's required torque value unchanged.

Images