A method for calibrating starting and gear shifting speed of AMT of commercial vehicle under high altitude working condition

Abstract

The present application relates to the field of vehicle starting and shift speed calibration, and particularly relates to a kind of calibration method of starting and shift speed of commercial vehicle AMT under high altitude working condition. It includes: under different altitudes, the starting speed of vehicle economy mode and power mode is calibrated respectively;When the altitude is lower, it is judged whether the shift speed of vehicle in economy mode can keep the preset low fuel consumption interval, and the upshift and downshift points are adjusted according to the judgment result;When the altitude is higher, it is judged whether the shift speed of vehicle in economy mode can keep the preset low fuel consumption interval while exerting maximum driving force, and the upshift and downshift points are adjusted according to the judgment result;It is judged whether the shift speed of vehicle in power mode can exert maximum driving force, and the upshift and downshift points are adjusted according to the judgment result. The calibrated power mode can exert the vehicle power under plateau working condition to the best, and the economy mode can keep enough power under plateau environment while significantly reducing fuel consumption.

Description

TECHNICAL FIELD

[0001] The application relates to a vehicle starting and gear shifting speed calibration method, in particular to a calibration method for starting and gear shifting speed of a commercial vehicle AMT under high-altitude working conditions. BACKGROUND

[0002] With the rapid development of the commercial vehicle industry, the requirements of the automobile market for commercial vehicles are higher and higher. The AMT is a transmission device capable of realizing automatic gear shifting according to the vehicle running state and the vehicle driving road environment, and is more in line with the young customer group. The AMT can completely liberate the right hand and left foot of the driver, and greatly reduces the driving intensity for a long time.

[0003] Commercial vehicles are not only applied to plain areas, but also to high-altitude domestic markets such as Yunnan, Guizhou, Sichuan, Qinghai and Tibet, and foreign markets such as Chile, Argentina and the Middle East. The altitudes of these regions are relatively high, generally ranging from 1800m to 4700m. The power of the vehicle is greatly affected under high-altitude working conditions, resulting in poor climbing power and difficulty in meeting the use requirements of vehicles in the specific region.

[0004] The gearbox is a core component in the normal power control system. Different gearbox control programs determine the differences in vehicle power and economy. Usually, a cargo truck will be calibrated with two programs, an economic mode and a power mode, when it is delivered from the factory.

[0005] The traditional economic mode program is only suitable for a certain specific slope road condition. When encountering variable-altitude road conditions with large altitude variance, this single program cannot adapt to multiple road conditions. For example, when the driver sets the initial economic mode program to adapt to 2000m altitude road conditions, when the vehicle travels to 3000m altitude road conditions, the torque required by the vehicle at 3000m altitude road conditions is greater than that at 2000m altitude road conditions. At this time, the gear shifting speed set for 2000m altitude road conditions is too low for 3000m altitude road conditions, and high gear, low speed and high torque engine working conditions occur. Referring to the universal characteristic diagram, the working condition point is shifted to the upper left corner, deviating from the engine economic working condition interval. Therefore, using only one economic mode to cope with different high altitudes cannot make the engine always in the economic working condition interval, resulting in poor fuel economy of the vehicle. Similarly, using only one power mode to cope with different high altitudes cannot make the engine always in the maximum driving force, resulting in poor vehicle power.

[0006] Chinese patent CN115077907A discloses a highland working condition performance test method for a plain vehicle type. The method collects plateau external characteristics of different engines at different altitudes, establishes a database of different engine plateau external characteristics, and matches corresponding plateau external characteristic data from the database according to the development needs of specific regional users. The engine external characteristic data is written to the full throttle engine of the vehicle, and the vehicle with updated engine external characteristics is checked. If the check meets the expectations, the vehicle can directly use the hub to effectively perform a highland performance test. However, this method does not test according to the needs of the power mode and the economic mode, so it still cannot solve the above technical problems. SUMMARY

[0007] The purpose of the present application is to solve the technical problem that using the same economic mode and power mode cannot always make the vehicle in the best fuel economy and maximum driving force state under different high-altitude working conditions, and to provide a calibration method for starting and shifting speed of commercial vehicle AMT under high-altitude working conditions.

[0008] To achieve the above purpose, the technical solution adopted by the present application is:

[0009] A calibration method for starting and shifting speed of commercial vehicle AMT under high-altitude working conditions, characterized in that it comprises the following steps:

[0010] S1. Under different altitudes, the starting speed of the vehicle in the economic mode and the power mode under full load is calibrated respectively by combining the engine external characteristic curve of the vehicle, and the engine starting target speed and the clutch engagement slope during starting are adjusted so that the starting torque of the vehicle engine under different altitudes meets the corresponding preset requirements respectively;

[0011] S2. When the altitude is lower than the preset altitude, it is judged whether the shifting speed of the vehicle in the economic mode at different altitudes can keep the preset low fuel consumption interval around the engine universal characteristic curve, if not, the upshift and downshift points are adjusted based on the preset upshift and downshift point calibration data, if yes, the shifting speed calibration in the economic mode at the corresponding altitude is completed;

[0012] When the altitude is higher than the preset altitude, it is judged whether the shifting speed of the vehicle in the economic mode at different altitudes can keep the preset low fuel consumption interval around the engine universal characteristic curve while exerting the maximum driving force around the engine external characteristic curve and the driving force curve, if not, the upshift and downshift points are adjusted based on the preset upshift and downshift point calibration data, if yes, the shifting speed calibration in the economic mode at the corresponding altitude is completed;

[0013] S3, respectively judge whether the shift speed of the vehicle in different altitude power modes can exert maximum driving force around the engine external characteristic curve and the driving force curve, if not, adjust the upshift and downshift points based on preset upshift and downshift point calibration data, if yes, complete the shift speed calibration in the corresponding altitude power mode; complete the calibration of the start-up and shift speed in the high altitude working condition.

[0014] Further, S1 is specifically:

[0015] S1.1, at the first altitude, based on the initial engine start-up target speed of the vehicle and the clutch engagement slope during the start-up process, in combination with the engine external characteristic curve of the vehicle, the start-up speed of the vehicle in the full load condition under the economic mode and the power mode is calibrated respectively, the engine start-up target speed is improved, the clutch engagement slope during the start-up process is reduced, so that the start-up torque of the engine of the vehicle meets the preset requirement;

[0016] S1.2, at the second altitude, based on the engine start-up target speed of the vehicle at the first altitude and the clutch engagement slope during the start-up process, in combination with the engine external characteristic curve of the vehicle, the start-up speed of the vehicle in the full load condition under the economic mode and the power mode is calibrated respectively, the engine start-up target speed is improved, the clutch engagement slope during the start-up process is reduced, so that the start-up torque of the engine of the vehicle meets the preset requirement;

[0017] S1.3, at the third altitude, based on the engine start-up target speed of the vehicle at the second altitude and the clutch engagement slope during the start-up process, in combination with the engine external characteristic curve of the vehicle, the start-up speed of the vehicle in the full load condition under the economic mode and the power mode is calibrated respectively, the engine start-up target speed is improved, the clutch engagement slope during the start-up process is reduced, so that the start-up torque of the engine of the vehicle meets the preset requirement;

[0018] The first altitude < the preset altitude < the second altitude < the third altitude.

[0019] Further, S2 is specifically:

[0020] S2.1, at the first altitude, judge whether the shift speed of the vehicle in the economic mode can keep the preset low fuel consumption interval around the engine universal characteristic curve, if not, adjust the upshift and downshift points based on preset upshift and downshift point calibration data, if yes, complete the shift speed calibration in the economic mode;

[0021] S2.2, at the second and third altitudes, judging whether the shift speed of the vehicle in the economy mode can keep the preset low fuel consumption interval around the engine universal characteristic curve while exerting the maximum driving force around the engine outer characteristic curve and the driving force curve, if not, adjusting the upshift and downshift points based on the preset upshift and downshift point calibration data, if yes, completing the shift speed calibration in the economy mode.

[0022] Further, S3 is specifically:

[0023] S3.1, at the first altitude, judging whether the shift speed of the vehicle in the power mode can exert the maximum driving force around the engine outer characteristic curve, if not, adjusting the upshift and downshift points based on the preset upshift and downshift point calibration data, if yes, completing the shift speed calibration in the power mode;

[0024] S3.2, at the second altitude, judging whether the shift speed of the vehicle in the power mode at different throttle openings can all exert the maximum driving force around the engine outer characteristic curve and the driving force curve, and the upshift speed of the engine is not lower than the preset speed when the throttle opening is lower than the preset opening, if not, adjusting the upshift and downshift points at different throttle openings based on the preset upshift and downshift point calibration data, if yes, completing the shift speed calibration in the power mode;

[0025] S3.3, at the third altitude, judging whether the shift speed of the vehicle in the power mode can exert the maximum driving force around the engine outer characteristic curve and the driving force curve, if not, adjusting the upshift and downshift points based on the preset upshift and downshift point calibration data on the basis of the upshift and downshift points adjusted at the second altitude, if yes, completing the shift speed calibration in the power mode.

[0026] Further, S3.2 is specifically:

[0027] At the second altitude, judging whether the shift speed of the vehicle in the power mode at the throttle opening of 50% or below, 50%, 50%-90% and 100% can all exert the maximum driving force around the engine outer characteristic curve and the driving force curve, and the upshift speed of the engine is not lower than the preset speed when the throttle opening is 50% or below, if not, adjusting the upshift and downshift points at different throttle openings based on the preset upshift and downshift point calibration data, if yes, completing the shift speed calibration in the power mode.

[0028] Further, the range of the first altitude H1 is 1500m≤H1<3000m, the range of the second altitude H2 is 3000m≤H2<4000m, the range of the third altitude H3 is H3≥4000m, and the preset altitude H is 3000m.

[0029] Further, the engine external characteristic curve, the engine universal characteristic curve and the driving force curve are respectively the standard external characteristic curve, the standard universal characteristic curve and the standard driving force curve of the engine, or are respectively measured by collecting actual data in advance.

[0030] The present application has the following advantages:

[0031] The present application calibrates the shift speed and the starting speed of the economic mode and the power mode at different altitudes, so that the vehicle can exert the power of the vehicle at high altitude to the best in the power mode, and can keep enough power and significantly reduce fuel consumption in the economic mode at high altitude; the two modes have their own advantages and are different in style, which is convenient for the driver to choose the suitable driving mode. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 is the external characteristic curve of the 4.5L diesel engine in the embodiment of the present application;

[0033] Figure 2 is the engine driving force curve in the embodiment of the present application;

[0034] Figure 3 is the engine universal characteristic curve in the embodiment of the present application;

[0035] Figure 4 is the calibration upshift point speed of the gearbox and the corresponding horizontal and vertical coordinate diagram in the embodiment of the present application;

[0036] Figure 5 is the calibration downshift point speed of the gearbox and the corresponding horizontal and vertical coordinate diagram in the embodiment of the present application;

[0037] Figure 6 is the calibration principle diagram of the starting at high altitude in the embodiment of the present application. DETAILED DESCRIPTION

[0038] In order to make the purpose, advantages and characteristics of the present application more clear, the following will further describe the calibration method of the starting and the shift speed of the commercial vehicle AMT at high altitude in the present application in combination with the drawings and specific embodiments. The advantages and characteristics of the present application will be more clear according to the following specific embodiments.

[0039] Taking a diesel engine with a present displacement of 4.5L as an example, the external characteristic curves of the engine at different altitudes are as shown in the attached Figure 1It can be found that the engine's own external characteristic curve at 2000m altitude is not much different from that on the plain, but the torque in the low speed range is significantly smaller than that on the plain. Therefore, in the case of an altitude of about 2000m, the AMT calibration needs to increase the engine starting target speed and reduce the clutch engagement slope during starting, so that the vehicle can smoothly overcome the current resistance during starting at high altitude, and fully improve the starting ability of the vehicle at an altitude of 2000m. Because the engine's external characteristic curve at 2000m altitude is generally comparable to that on the plain, the shift speed can be specifically set based on the parameters on the plain.

[0040] When the vehicle is at an altitude of about 3000m, the oxygen content at the current altitude has decreased significantly, combustion is not sufficient, and power has decreased significantly. The engine's external characteristic curve at an altitude of 3000m is significantly different from that on the plain. For altitudes above 3000m, the gearbox needs to be recalibrated according to the current engine external characteristic curve, so that the shift speed can be kept in the speed range where the torque decay is the smallest for as long as possible, such as the speed range of 1300-1900rpm, so that the engine's torque can be kept in a higher range.

[0041] Referring to Figure 6 When the vehicle is at an altitude of 4000m or above, the overall external characteristic of the engine is weak, and the torque decreases significantly, so the starting situation at altitudes above 4000m needs to be optimized, the clutch engagement speed is reduced again, the target speed of the engine during starting is increased again, and the starting of gear 1 is reduced, so as to improve the starting ability of the vehicle at high altitudes as much as possible. At the same time, because the torque in the overall speed range of the engine decreases and the power weakens, the torque decay in the high speed range is lower, indicating that the power of the vehicle in the high speed range is weak, so the shift point of the vehicle needs to be adjusted so that the engine speed can be kept in the range of 1200-1900rpm as much as possible.

[0042] The engine external characteristic curve, the engine universal characteristic curve, and the driving force curve respectively use the standard external characteristic curve, the standard universal characteristic curve, and the standard driving force curve of the engine provided by the main machine factory. However, in some cases, the actual performance of the engine does not match the provided data, so the actual data can be collected and measured to draw the curves as needed.

[0043] Through the plateau calibration test of multiple engines, it is found that different engines have similar performance at high altitudes. The external characteristic at an altitude below 2000m is less different, and the torque in the low speed range is weak. The external characteristic at an altitude of 3000m is significantly different, and the torque decay in the high speed range is obvious. The overall external characteristic of the engine at an altitude above 4000m decreases significantly, and the torque power in the high and low speed ranges is small.

[0044] This embodiment provides a method for calibrating the starting and shifting speeds of a commercial vehicle's AMT (Automated Manual Transmission) under high-altitude operating conditions, specifically including the following steps:

[0045] B1. Starting and shifting speed calibration at an altitude of 2000m:

[0046] B1.1 Based on the vehicle's initial engine starting target speed and the clutch engagement slope during the starting process (refer to the parameters set in the plain area), combined with... Figure 1 The external characteristic curves of the vehicle's engine are used to test and calibrate the start-up of the vehicle in both economy and power modes under full load conditions. This increases the target starting speed of the engine and reduces the clutch engagement slope during the start-up process, so that the starting torque of the vehicle's engine meets the preset requirements.

[0047] B1.2 Determine whether the vehicle's shift points in economy mode can revolve around [the specified range]. Figure 3 If the engine's universal characteristic curve remains within the preset low fuel consumption range, then the shift speed calibration in economy mode is completed; otherwise, based on... Figure 4 and Figure 5 The preset shift point calibration data is used to adjust the shift points.

[0048] B1.3 Determine whether the vehicle's shift points in power mode can revolve around [the specified range]. Figure 1 External characteristic curves of the engine and Figure 2 If the driving force curve reaches its maximum driving force, then the shift speed calibration in the power mode is completed; otherwise, based on... Figure 4 and Figure 5 The preset shift point calibration data is used to adjust the shift points.

[0049] B2. Starting and shifting speed calibration at an altitude of 3000m:

[0050] The vehicle underwent transmission start-up and shift point calibration tests at an altitude of 3000m. At altitudes of 3000m and above, the atmospheric pressure is relatively thin, resulting in a significant reduction in engine power compared to lower altitudes. Therefore, adjustments need to be made based on... Figure 1 Engine external characteristic curves and Figure 2 The engine drive system aims to recalibrate the shift points for different power modes, combined with... Figure 1 and Figure 3 The engine universal characteristic curve is used to calibrate the shift points in economy mode.

[0051] B2.1 Based on the target engine starting speed and clutch engagement slope during the starting process of the vehicle at an altitude of 2000m, combined with... Figure 1The engine external characteristic curves of the vehicle were used to test and calibrate the start-up of the vehicle in economy mode and power mode under full load. Based on the engine start-up target speed and clutch engagement slope calibrated at an altitude of 2000m, the engine start-up target speed was further increased and the clutch engagement slope was reduced so that the engine start-up torque of the vehicle at an altitude of 3000m meets the preset requirements.

[0052] B2.2. Sequentially determine whether the shift points of the vehicle in power mode at throttle openings below 50%, 50%, 50%-90%, and 100% can all revolve around [the specified range]. Figure 1 External characteristic curves of the engine and Figure 2 The driving force curve utilizes maximum driving force, and when the throttle opening is below 50%, the engine's upshift speed is not lower than the preset speed. The preset speed can be set according to the actual or standard speed. If so, the shift speed calibration in the power mode is completed; otherwise, it is based on... Figure 4 and Figure 5 The preset upshift / downshift point calibration data is used to adjust the upshift / downshift points at various throttle openings.

[0053] B2.3 Determine whether the vehicle's shift points in economy mode are within a certain range. Figure 1 External characteristic curves of the engine and Figure 2 The driving force curve can maximize driving force while circling around Figure 3 If the engine's universal characteristic curve remains within the preset low fuel consumption range, then the shift speed calibration in economy mode is completed; otherwise, based on... Figure 4 and Figure 5 The preset shift points are used to adjust the shift points. Specifically, the shift points can be adjusted based on the shift points calibrated in the power mode at an altitude of 2000m. Based on the torque at the current speed, the gear speed should be kept within the fuel-efficient range for a longer period of time. The power needs of the driver should also be met when the throttle is fully depressed. The shift points are lower than those in the power mode, but they should also meet the actual driving needs and acceleration.

[0054] B3. Starting and shifting speed calibration at an altitude of 4000m:

[0055] The primary purpose of operating at altitudes above 4000m is to ensure the vehicle's power during driving. In addition to optimizing the above-mentioned aspects, it is also necessary to adjust the starting and shifting speeds according to the current altitude. A larger gear ratio in the transmission can enable the vehicle to have better starting performance. Specifically, it is also necessary to test the vehicle's ability to climb hills fully loaded at high altitudes.

[0056] B3.1 Based on the target engine starting speed and clutch engagement slope during starting, at an altitude of 3000m, combined with...Figure 1 Test and calibrate the engine external characteristic curve of the vehicle, respectively test and calibrate the start of the vehicle in the economy mode and the power mode under full load, increase the engine start target speed, and reduce the clutch engagement slope during the start process, so that the start torque of the vehicle engine at 4000m altitude meets the preset requirements.

[0057] B3.2, determine whether the shift speed of the vehicle in the power mode can be around Figure 1 the engine external characteristic curve and Figure 2 the maximum driving force curve to develop the maximum driving force, if yes, complete the shift speed calibration in the power mode, if no, on the basis of the adjusted upshift and downshift points at 3000m altitude, adjust the upshift and downshift points based on Figure 4 and Figure 5 the preset upshift and downshift point calibration data in the middle.

[0058] B3.3, above 4000m altitude, mainly need to meet the power of the vehicle, to ensure that the vehicle can smoothly pass through the comprehensive road conditions, but it is not appropriate to make the shift point too high, otherwise the speed will rise too slowly after the high speed torque decays, resulting in high fuel consumption and no shift.

[0059] Therefore, it is necessary to determine whether the shift speed of the vehicle in the economy mode can be around the engine external characteristic curve and the maximum driving force curve to develop the maximum driving force, while keeping the preset low fuel consumption interval around the engine universal characteristic curve, if yes, complete the shift speed calibration in the economy mode, if no, adjust the upshift and downshift points based on Figure 4 and Figure 5 the preset upshift and downshift point calibration data in the middle.

Claims

1. A method for calibrating the starting and shifting speeds of a commercial vehicle's AMT under high-altitude operating conditions, characterized in that... Includes the following steps: S1. At different altitudes, based on the vehicle's engine external characteristic curve, the starting speed of the vehicle in economy mode and power mode under full load is calibrated respectively. The engine starting target speed and the clutch engagement slope during the starting process are adjusted so that the starting torque of the vehicle engine at different altitudes meets the corresponding preset requirements. S2. When the altitude is lower than the preset altitude, determine whether the shift speed of the vehicle in different altitude economic modes can maintain the preset low fuel consumption range around the engine universal characteristic curve. If not, adjust the shift points based on the preset upshift and downshift point calibration data. If yes, complete the shift speed calibration in the corresponding altitude economic mode. When the altitude is higher than the preset altitude, the shift speed of the vehicle in different altitude economic modes is judged to determine whether it can exert the maximum driving force around the engine external characteristic curve and the driving force curve, while maintaining the preset low fuel consumption range around the engine universal characteristic curve. If not, the shift points are adjusted based on the preset shift point calibration data. If so, then complete the shift speed calibration for the corresponding altitude economic mode; S3. Determine whether the shift points of the vehicle in different altitude power modes can exert maximum driving force around the engine external characteristic curve and driving force curve. If not, adjust the shift points based on the preset shift point calibration data. If yes, complete the shift point calibration for the corresponding altitude power mode. The starting and shifting speeds under high-altitude operating conditions have been calibrated.

2. The method for calibrating the starting and shifting speeds of a commercial vehicle AMT under high-altitude operating conditions according to claim 1, characterized in that, S1 specifically refers to: S1.1 At the first altitude, based on the initial engine starting target speed and the clutch engagement slope during the starting process, and combined with the engine external characteristic curve of the vehicle, the starting speed of the economic mode and power mode under full load is calibrated respectively, so as to increase the engine starting target speed and reduce the clutch engagement slope during the starting process, so that the starting torque of the vehicle engine meets the preset requirements. S1.2 At the second altitude, based on the engine starting target speed and clutch engagement slope of the vehicle at the first altitude, and combined with the engine external characteristic curve of the vehicle, the starting speed of the economic mode and power mode under full load is calibrated respectively, so as to increase the engine starting target speed and reduce the clutch engagement slope during the starting process, so that the starting torque of the vehicle engine meets the preset requirements. S1.3 At the third altitude, based on the engine starting target speed and clutch engagement slope of the vehicle at the second altitude, and combined with the engine external characteristic curve of the vehicle, the starting speed of the economic mode and power mode under full load is calibrated respectively, so as to increase the engine starting target speed and reduce the clutch engagement slope during the starting process, so that the starting torque of the vehicle engine meets the preset requirements. The first altitude < the preset altitude < the second altitude < the third altitude.

3. The method for calibrating the starting and shifting speeds of a commercial vehicle AMT under high-altitude operating conditions according to claim 2, characterized in that, S2 specifically refers to: S2.1 At the first altitude, determine whether the vehicle's shift speed in economy mode can maintain a preset low fuel consumption range around the engine's universal characteristic curve. If not, adjust the shift points based on the preset upshift / downshift point calibration data. If so, then complete the shift speed calibration in economy mode; S2.2 At the second and third altitudes, determine whether the vehicle's shift speed in economy mode can exert maximum driving force around the engine's external characteristic curve and driving force curve while maintaining a preset low fuel consumption range around the engine's universal characteristic curve. If not, adjust the shift points based on the preset upshift / downshift point calibration data; if yes, complete the shift speed calibration in economy mode.

4. The method for calibrating the starting and shifting speeds of a commercial vehicle AMT under high-altitude operating conditions according to claim 3, characterized in that, S3 specifically refers to: S3.1 At the first altitude, determine whether the vehicle's shift speed in power mode can exert maximum driving force around the engine's external characteristic curve and driving force curve. If not, adjust the shift points based on the preset upshift / downshift point calibration data; if so, complete the shift speed calibration in power mode. S3.2 At the second altitude, sequentially determine whether the shift speed of the vehicle at different throttle openings in power mode can exert the maximum driving force around the engine external characteristic curve and driving force curve, and whether the engine upshift speed is not lower than the preset speed when the throttle opening is lower than the preset opening. If not, adjust the upshift and downshift points at different throttle openings based on the preset upshift and downshift point calibration data. If so, then complete the shift speed calibration in power mode; S3.3 At the third altitude, determine whether the vehicle's shift speed in power mode can exert maximum driving force around the engine's external characteristic curve and driving force curve. If not, adjust the shift points based on the preset shift point calibration data, based on the shift points adjusted in the power mode at the second altitude. If so, the shift speed calibration in power mode is completed.

5. The method for calibrating the starting and shifting speeds of a commercial vehicle AMT under high-altitude operating conditions according to claim 4, characterized in that, S3.2 specifically refers to: At the second altitude, the shift points of the vehicle in power mode are sequentially determined at throttle openings below 50%, 50%, 50%-90%, and 100% to ensure that the maximum driving force is achieved around the engine's external characteristic curve and driving force curve. Furthermore, when the throttle opening is below 50%, the engine's upshift speed is not lower than the preset speed. If not, the upshift and downshift points at each throttle opening are adjusted based on the preset upshift and downshift point calibration data. If yes, the shift point calibration in power mode is completed.

6. A method for calibrating the starting and shifting speeds of a commercial vehicle AMT under high-altitude operating conditions according to any one of claims 2-5, characterized in that: The range of the first altitude H1 is 1500m≤H1<3000m, the range of the second altitude H2 is 3000m<H2<4000m, the range of the third altitude H3 is H3≥4000m, and the preset altitude H is 3000m.

7. The method for calibrating the starting and shifting speeds of a commercial vehicle AMT under high-altitude operating conditions according to claim 1, characterized in that: The engine external characteristic curve, engine universal characteristic curve, and driving force curve are respectively derived from the engine's standard external characteristic curve, standard universal characteristic curve, and standard driving force curve, or are pre-drawn by collecting actual data.

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