An AMT over-shift coordination control method for an electrically driven trailer vehicle train

Abstract

This invention relates to an AMT (Automated Manual Transmission) gear shifting coordination control method for electric trailers, comprising: collecting driver's driving intention information, vehicle operating status parameter information, and road condition information; analyzing the driver's driving style characteristics based on the driver's driving intention information and vehicle operating status parameters to complete the driver's operation decision; setting a control strategy based on accelerator pedal opening; setting a shifting strategy based on the drive mode, with the VCU (Vehicle Control Unit) adjusting the transmission according to different drive modes to achieve gear shifting, including skipping, upshifting, and downshifting; setting skipping and upshifting control strategies based on engine speed, accelerator pedal opening, and accelerator pedal opening response time when the vehicle is accelerating; setting a downshifting strategy based on vehicle acceleration and gradient, and accelerator pedal opening under overtaking or climbing conditions; and switching and optimizing driver behavior to improve the overall driving experience and vehicle power performance.

Description

Technical Field

[0001] This invention relates to the field of commercial vehicle control technology, and in particular to a coordinated control method for skip-level shifting of an AMT (Automated Manual Transmission) system in an electric trailer. Background Technology

[0002] In recent years, automatic transmission technology has become a trend in commercial vehicles, and major domestic commercial vehicle manufacturers are also developing and promoting it. More and more commercial vehicles in my country are equipped with AMT (automatic transmission), and the popularization of AMT in commercial vehicles has become a trend. The shifting quality and fuel consumption of AMT directly affect passenger satisfaction with the vehicle, so major automakers have invested considerable resources in its research.

[0003] With continuous improvements, AMT (Automated Manual Transmission) has demonstrated numerous advantages over widely used manual transmissions. These advantages include: ① Effectively reducing driver workload and ease of operation, thus improving safety during traffic. ② Autonomous shifting in response to different road conditions, improving vehicle power and fuel economy, and reducing emissions. Currently, the shifting strategy of heavy-duty commercial vehicle AMTs primarily focuses on matching input parameters such as accelerator pedal position and road gradient. Because they cannot recognize road conditions and driver habits, upshifts and downshifts are not timely, resulting in performance inferior to manual transmissions and the inability to perform skip-gear operations in certain situations. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a coordinated control method for skip-level shifting in an AMT (Automated Manual Transmission) system for electric trailers.

[0005] This invention is achieved using the following technical solution:

[0006] A coordinated control method for skip-shift gearing in an AMT (Automated Manual Transmission) system for an electric trailer, comprising:

[0007] S1, Driving information collection, including driver's driving intention information collection, vehicle operating status parameter information collection and road condition information collection;

[0008] S2. Driver driving style judgment: By analyzing and judging the driver's driving style characteristics based on the driver's driving intention information and vehicle operating status parameters, the driver's operational decision is completed.

[0009] S3. Define the accelerator pedal opening. Based on the accelerator pedal opening a, set the AMT control strategy as no accelerator signal A0, low accelerator region A1, medium accelerator region A2, high accelerator region A3, and full accelerator region A4.

[0010] S4. Define the shifting law: Based on the driving mode, set the AMT shifting strategy to the economic mode, normal mode, and power mode. The vehicle control unit (VCU) adjusts the transmission according to different driving modes to achieve shifting, where shifting includes skipping gears, upshifting, and downshifting.

[0011] S5. Define the skip-gear and upshift strategies: When the vehicle is accelerating, based on the engine speed, throttle pedal opening, and throttle pedal opening response time, set the skip-gear and upshift control strategies.

[0012] S6. Define the downshift strategy: Based on the vehicle acceleration and slope under overtaking or climbing conditions, and the throttle pedal opening changes from the low throttle region A1 to the high throttle region A3 or the full throttle region A4 within a short time, set it as the downshift strategy.

[0013] The articulated vehicle includes a tractor equipped with a 16-speed automatic transmission and a semi-trailer equipped with a 4-speed transmission.

[0014] Further, in S1, the road condition information includes the driving road surface slope and the road surface grade; the driving intention information and the vehicle operation state parameter information are obtained through on-vehicle sensors and the CAN bus. The vehicle operation state information includes the vehicle mass, ramp slope parameter, and vehicle performance parameters. The vehicle performance parameters include the engine speed, torque, vehicle speed, current gear, target gear, input shaft speed, throttle pedal position, brake pedal position, longitudinal acceleration, torque signal, altitude, slope, instantaneous fuel consumption, cumulative fuel consumption, and driving mileage.

[0015] Further, in S3, the no-throttle signal A0 is a = 0%, the low throttle region A1 is 0% < a ≤ 30%, the medium throttle region A2 is 30% < a ≤ 60%, the high throttle region A3 is 60% < a ≤ 90%, and the full throttle region A4 is 90% < a ≤ 100%.

[0016] Further, in S5, when driving the vehicle to accelerate on a road with a road surface slope of 0, if the throttle pedal opening a uses the no-throttle signal A0, the low throttle region A1, the medium throttle region A2 for positioning, or the throttle pedal opening a does not reach the high throttle region A3 or the full throttle region A4 for positioning, and the throttle pedal opening response time is less than the set value T1, then execute the upshift strategy; if the throttle pedal opening a uses the high throttle region A3 or the full throttle region A4 for positioning and the throttle pedal opening response time is greater than the set value T1, then execute the skip-gear strategy.

[0017] Further, in S6, under the overtaking or climbing conditions, the vehicle acceleration is greater than 0 m / s 2If the accelerator pedal opening changes from the low throttle region A1 to the high throttle region A3 or the full throttle region A4 within a short period of time, and the accelerator pedal opening is positioned in the high throttle region A3 or the full throttle region A4, then a downshift strategy is executed.

[0018] Furthermore, to ensure relative stability of the vehicle's state before and after gear shifting, the resistance encountered by the main vehicle and the electric drive axle trailer during driving should be assessed before shifting. Based on this resistance, the change in speed of the main vehicle and the electric drive axle trailer during gear shifting should be calculated. This speed change is then converted into corresponding speed compensation, thereby adjusting the engine speed to improve the efficiency of skip-shifting. The speed compensation is as follows:

[0019] a 阻 =-F 阻 / δM

[0020] In the formula, α 阻 For drag deceleration, F 阻 Let M be the driving resistance, M be the total mass of the vehicle after loading, and δ be the change in the total mass of the vehicle after loading.

[0021] Furthermore, to avoid speed loss during gear shifts, the vehicle speed during gear shifts needs to be adjusted to achieve dynamic speed control.

[0022] V actshift =V shift +|ΔV|;ΔV=t shift ×a 阻

[0023] In the formula, α 阻 For drag deceleration, V actshift To compensate for the vehicle speed after shifting gears, V shift ΔV is the actual shift speed, ΔV is the speed compensation, and t is the actual shift speed. shift The time of power interruption.

[0024] Compared with the prior art, the present invention has the following beneficial technical effects:

[0025] Based on the analysis of throttle opening under driver behavior, the switching and optimization of the driver's throttle shifting strategy are carried out by defining different throttle opening distributions on flat roads, uphill, and downhill, thereby improving the overall driving experience and vehicle power performance. Attached Figure Description

[0026] Figure 1 This is a flowchart of the control system of the present invention;

[0027] Figure 2 The process of the second embodiment of the present invention Figure 1 ;

[0028] Figure 3 The process of the second embodiment of the present invention Figure 2 ;

[0029] Figure 4 The process of the third embodiment of the present invention Figure 1 ;

[0030] Figure 5 The process of the third embodiment of the present invention Figure 2 . Detailed Implementation

[0031] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0032] Example 1

[0033] When developing a skip-shift strategy, factors such as the degree of throttle input, the steepness of the slope, the vehicle's load, and the driving conditions during cornering should be considered.

[0034] Accelerator: 0%, 30%, 60%, 90%, 100%;

[0035] Positive slope: 0%, 0%-1.5%, 1.5%-3%, 3%-4.5%, 4.5%-6%, 6%-8%, greater than 8%;

[0036] Negative slope: corresponds to positive slope value

[0037] Vehicle weights: 20 tons, 25 tons, 30 tons, 35 tons, 40 tons, 45 tons, 50 tons;

[0038] The transmissions of the main vehicle and the electric drive axle trailer need to make comprehensive judgments based on the position of the accelerator pedal, the gradient, and the weight of the vehicle in order to achieve coordinated control of overtaking shifting operations.

[0039] like Figure 1 As shown, a coordinated control method for skip-shift gearing in an AMT (Automated Manual Transmission) system for an electric trailer includes:

[0040] S1, Driving information collection, including driver's driving intention information collection, vehicle operating status parameter information collection and road condition information collection;

[0041] S2. Determine the driver's driving style. Analyze and judge the characteristics of the driver's driving style through the driver's driving intention information and vehicle operating state parameters, and complete the driver's operation decision-making;

[0042] S3. Define the throttle pedal opening. Based on the throttle pedal opening a, set the AMT control strategy as no throttle signal A0, low throttle area A1, medium throttle area A2, high throttle area A3, and full throttle area A4;

[0043] S4. Define the shifting rule: Based on the driving mode, set the AMT shifting strategy as economy mode, normal mode, and power mode. The vehicle control unit VCU completes the adjustment of the transmission according to different driving modes to achieve shifting, where shifting includes skipping gears, upshifting, and downshifting;

[0044] S5. Define the skip-gear and upshift strategies: When the vehicle is accelerating, based on the engine speed, throttle pedal opening, and throttle pedal opening response time, set the skip-gear and upshift control strategies;

[0045] S6. Define the downshift strategy: Based on the vehicle acceleration and slope under overtaking or climbing conditions, and the throttle pedal opening changes from the low throttle area A1 to the high throttle area A3 or the full throttle area A4 within a short time, set it as the downshift strategy.

[0046] The articulated vehicle includes a tractor with a 16-speed automatic transmission and an electric drive axle trailer with a 4-speed transmission.

[0047] In S1, the road condition information includes the driving road surface slope and road surface grade; the driving intention information and vehicle operating state parameter information are obtained through on-vehicle sensors and the CAN bus. The vehicle operating state information includes vehicle mass, ramp slope parameter, and vehicle performance parameters. The vehicle performance parameters include engine speed, torque, vehicle speed, current gear, target gear, input shaft speed, throttle pedal position, brake pedal position, longitudinal acceleration, torque signal, altitude, slope, instantaneous fuel consumption, cumulative fuel consumption, and driving mileage.

[0048] In S3, the no throttle signal A0 is a = 0%, the low throttle area A1 is 0% < a ≤ 30%, the medium throttle area A2 is 30% < a ≤ 60%, the high throttle area A3 is 60% < a ≤ 90%, and the full throttle area A4 is 90% < a ≤ 100%.

[0049] In S5, when a vehicle is accelerating on a road with a gradient of 0, if the accelerator pedal opening a is positioned in the no accelerator signal A0, low accelerator region A1, or medium accelerator region A2, or if the accelerator pedal opening a does not reach the high accelerator region A3 or full accelerator region A4, and the accelerator pedal opening response time is less than the set value T1, then an upshift strategy is executed; if the accelerator pedal opening a is positioned in the high accelerator region A3 or full accelerator region A4, and the accelerator pedal opening response time is greater than the set value T1, then a skip-gear logic is activated, and a skip-gear strategy is executed.

[0050] When the driver applies a large throttle, that is, when the throttle opening a is positioned in the high throttle area A3 and the full throttle area A4, the driver has a need for rapid acceleration of the vehicle. At this time, the engine outputs a large torque and the vehicle begins to accelerate. If the driver continues to apply a large throttle, the vehicle continues to accelerate. That is, if the throttle pedal opening response time is greater than the set value T1, the shifting condition is met, and the shifting logic is activated and the shifting strategy is executed.

[0051] If the driver applies the accelerator for too short a time, and the vehicle's acceleration increases but then quickly returns to normal speed, meaning the accelerator pedal opening response time is less than the set value T1, the engine speed rises too little and the conditions for shifting gears are not met, then the shifting logic cannot be activated.

[0052] Taking a 16-speed transmission as an example, under the condition that all conditions are met, it is feasible to skip to 2nd or 3rd gear when executing the skip-gear strategy:

[0053] 2nd gear skipping: The time it takes for the current vehicle speed to increase to the next upshift speed meets the skipping condition, at which point the skipping logic is activated; the highest skipping speed is 13th gear, skipping is not allowed above 13th gear, and sequential upshifting starts from 13th gear;

[0054] 3rd gear skipping: The time it takes for the current vehicle speed to increase to the next upshift speed meets the skipping condition, at which point the skipping logic is activated; the highest skipping speed is 12th gear, skipping is not allowed above 12th gear, and sequential upshifting starts from 12th gear;

[0055] When shifting gears across gears, the tractor vehicle can accelerate by skipping three gears, while the electric drive axle is equipped with a two-gear upshift operation.

[0056] In S6, during overtaking or hill climbing, the vehicle acceleration is greater than 0 m / s². 2 If the accelerator pedal opening changes from the low throttle region A1 to the high throttle region A3 or the full throttle region A4 within a short period of time, and the accelerator pedal opening is positioned in the high throttle region A3 or the full throttle region A4, then a downshift strategy is executed.

[0057] When the vehicle is turning, a steering angle sensor monitors the turn. If the turning angle exceeds 45 degrees, the electric drive axle trailer will be unable to upshift or downshift. When the turning angle is less than 45 degrees, the electric drive axle trailer is only allowed to perform one gear shift.

[0058] During the process of upshifting, the tractor unit can upshift up to 3 gears, while the electric drive axle has the ability to keep the gear unchanged, upshift one gear, or upshift two gears.

[0059] When upshifting to overtake, the tractor unit can downshift up to three gears, while the electric drive axle can flexibly choose not to downshift, downshift by one gear, or downshift by two gears.

[0060] Given the fast shifting speed of a four-speed transmission, in order to protect the speed of the electric motor, its transmission system can only support a maximum downshift of two gears.

[0061] To ensure the relative stability of the vehicle's state before and after shifting gears, the resistance encountered by the main vehicle and the electric drive axle trailer during driving should be assessed before shifting gears. The change in speed of the main vehicle and the electric drive axle trailer during shifting should be calculated based on the resistance of the main vehicle and the electric drive axle trailer. Then, the change in speed of the main vehicle and the electric drive axle trailer should be converted into corresponding speed compensation, thereby adjusting the engine speed to improve the efficiency of skip-shifting.

[0062] Speed ​​compensation is:

[0063] a 阻 =-F 阻 / δM

[0064] In the formula, α 阻 For drag deceleration, F 阻 Let M be the driving resistance, M be the total mass of the vehicle after loading, and δ be the change in the total mass of the vehicle after loading.

[0065] Furthermore, to avoid speed loss during gear shifts, the vehicle speed during gear shifts needs to be adjusted to achieve dynamic speed control.

[0066] V actshift =V shift +|ΔV|;ΔV=t shift ×a 阻

[0067] In the formula, α 阻 For drag deceleration, V actshift To compensate for the vehicle speed after shifting gears, V shift ΔV is the actual shift speed, ΔV is the speed compensation, and t is the actual shift speed. shift The time of power interruption.

[0068] Example 2

[0069] like Figures 2-3 As shown:

[0070] When driving on a straight road, during normal acceleration and upshifting, the main vehicle can skip upshifts to 2nd or 3rd gear according to the torque requested by the driver; during the process of the main vehicle skipping upshifts to 2nd gear, the electric drive axle trailer can execute a strategy of not upshifting, upshifting to 1st gear, or skipping upshifting to 2nd gear; during the process of the main vehicle skipping upshifts to 3rd gear, the electric drive axle trailer can execute a strategy of upshifting to 1st gear or skipping upshifting to 2nd gear.

[0071] When driving on a straight road, during rapid acceleration and overtaking, the driver can downshift the main vehicle by 2 or 3 gears depending on the torque requested by the driver. During the downshift of the main vehicle by 2 gears, the electric drive axle trailer can either not downshift, downshift by 1 gear, or downshift by 2 gears. During the downshift of the main vehicle by 3 gears, the electric drive axle trailer can either not downshift, downshift by 1 gear, or downshift by 2 gears.

[0072] Example 3

[0073] like Figures 4-5 As shown:

[0074] To ensure vehicle safety and prevent excessive drive force output during cornering, the electric drive axle trailer is limited from skipping gears.

[0075] When driving on a curve, during normal acceleration and upshifting, the main vehicle can be shifted to 2nd or 3rd gear according to the torque requested by the driver. During the process of the main vehicle shifting to 2nd gear, the electric drive axle trailer can either not shift or shift to 1st gear. During the process of the main vehicle shifting to 3rd gear, the electric drive axle trailer can either not shift or shift to 1st gear.

[0076] When driving on a curve, during rapid acceleration and downshifting, the main vehicle can be downshifted by 2 or 3 gears according to the torque requested by the driver; during the downshifting of the main vehicle by 2 gears, the electric drive axle trailer can execute a strategy of not downshifting and downshifting by 1 gear; during the downshifting of the main vehicle by 3 gears, the electric drive axle trailer can execute a strategy of not downshifting and downshifting by 1 gear.

Claims

1. An electrically driven trailer automobile train (AMT) overgear shift coordination control method, characterized by, The method comprises the following steps: S1, driving information collection, including driver driving intention information collection, vehicle running state parameter information collection and road condition information collection; S2, driver driving style judgment, analyzing and judging the driver's driving style characteristics through the driver's driving intention information and vehicle running state parameters, and completing the driver's operation decision; S3, defining the accelerator pedal opening degree, setting the AMT control strategy as no throttle signal A0, low throttle area A1, medium throttle area A2, high throttle area A3 and full throttle area A4 based on the accelerator pedal opening degree a; S4, defining the shift schedule, setting the AMT shift strategy as the economy mode, the conventional mode and the power mode based on the driving mode, and the vehicle control unit VCU completes the adjustment of the transmission according to different driving modes to realize the shift, wherein the shift includes the skip shift, the upshift and the downshift; S5, defining the skip shift and upshift strategy: based on the engine speed, the accelerator pedal opening degree and the accelerator pedal opening degree response time, the skip shift and upshift control strategy is set when the vehicle accelerates on the road; S6, defining the downshift strategy: based on the vehicle acceleration and the slope under the overtaking or climbing working condition, the downshift strategy is set when the accelerator pedal opening degree changes from the low throttle area A1 to the high throttle area A3 or the full throttle area A4 in a short time; The automobile train comprises a main vehicle provided with a 16-gear automatic transmission and an electric drive axle trailer provided with a 4-gear transmission; In S5, when the vehicle accelerates on the road with a road slope of 0, the accelerator pedal opening degree a is positioned by using the no throttle signal A0, the low throttle area A1 and the medium throttle area A2, or the accelerator pedal opening degree a does not reach the high throttle area A3 or the full throttle area A4 positioning, and the accelerator pedal opening degree response time is less than the set value T1, then the upshift strategy is executed; If the accelerator pedal opening degree a is positioned by using the high throttle area A3 or the full throttle area A4 when the accelerator pedal opening degree response time is greater than the set value T1, then the skip shift strategy is executed.

2. The AMT override shift coordination control method of an electrically driven trailer-equipped automobile train according to claim 1, characterized by, In S1, the road condition information includes the road slope and the road grade; the driving intention information and the vehicle running state parameter information are obtained through the vehicle-mounted sensor and the CAN bus; the vehicle running state information includes the vehicle mass, the slope parameter and the vehicle performance parameter; the vehicle performance parameter includes the engine speed, the torque, the vehicle speed, the current gear, the target gear, the input shaft speed, the accelerator pedal position, the brake pedal position, the longitudinal acceleration, the torque signal, the altitude, the slope, the instantaneous fuel consumption, the cumulative fuel consumption and the driving distance.

3. The electrically driven trailer vehicle train AMT overdrive shift coordination control method according to claim 1, characterized by, In S3, the no throttle signal A0 is a=0%, the low throttle area A1 is 0% 4. The electrically driven towed vehicle automobile train (AMT) override shift coordination control method according to claim 1, characterized by, In S6, under the overtaking or climbing working condition, the vehicle acceleration is greater than 0 m / s 2 If the accelerator pedal opening degree is changed from the low accelerator area A1 to the high accelerator area A3 or the full accelerator area A4 in a short time, and the accelerator pedal opening degree is positioned in the high accelerator area A3 or the full accelerator area A4, the downshift strategy is executed.

5. The electrically driven trailer automobile train (AMT) override coordination control method according to claim 4, characterized by, To ensure the relative stability of the vehicle state before and after the gear shift, the resistance encountered by the host vehicle and the electric drive axle trailer during driving should be evaluated before the gear shift, and the change in the speed of the host vehicle and the electric drive axle trailer during the gear shift should be calculated according to the resistance of the host vehicle and the electric drive axle trailer, and then the change in the speed of the host vehicle and the electric drive axle trailer is converted into corresponding speed compensation, and the engine speed is adjusted to improve the efficiency of the gear shift up; The rotational speed compensation is: ​ In the formula, α 阻 is the resistance deceleration, F 阻 is the travel resistance, M is the total mass after the vehicle is loaded, δ is the change value of the total mass after the vehicle is loaded.

6. The electrically driven trailer automobile train (AMT) override coordination control method according to claim 5, wherein, To avoid the loss of vehicle speed during the gear shift, the vehicle speed during the gear shift needs to be adjusted to realize the dynamic adjustment of the vehicle speed during the gear shift: ； wherein α 阻 is the deceleration resistance, V actshift is the compensation after shift speed, V shift is the actual shift speed, Δ V is the speed compensation, t shift is the power cut-off time.

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