Performance analysis method for electric transmission system of pure electric mining dump truck

Abstract

A performance analysis method for an electric transmission system of a pure electric mining dump truck comprises the following steps: 1, checking a model selection result of a power transmission component: checking the maximum traction braking power and the maximum traction braking torque of a vehicle motor according to road conditions and vehicle parameters of vehicle operation, and drawing an operation characteristic curve; 2, traction gear shifting logic performance analysis: according to the running road condition of the vehicle, the lowest gear of the gearbox under the maximum climbing torque of the gearbox is matched, and gear shifting performance analysis of traction climbing of the gearbox is completed; 3, brake gear shifting logic performance analysis: according to the running road condition of the vehicle, matching the highest gear of the gearbox under the maximum downhill torque of the gearbox, and completing downhill gear shifting performance analysis of the gearbox; 4, traction efficiency analysis: according to the gear shifting logic in the step 2, calculating a common rotating speed interval of each gear and comparing the common rotating speed interval with a motor efficiency map; and 5, brake efficiency analysis: according to the gear shifting logic determined in the step (3.7), calculating a common rotating speed interval of each gear and comparing the common rotating speed interval with a motor efficiency map.

Description

Technical Field

[0001] The invention relates to the technical field of dump trucks, in particular to a performance analysis method of an electric transmission system of a pure electric mining dump truck. Background Art

[0002] At present, the common electric transmission system structure of pure electric mining dump trucks below 100 tons developed in China is a single motor with a gearbox. Due to the complex and changeable road conditions during vehicle operation, the system is prone to vehicle power and gear mismatches, resulting in insufficient power or insufficient electric braking force, affecting the safety and efficiency of vehicle transportation.

[0003] To evaluate whether the selected electric drive system can adapt to the road conditions, the traditional selection method generally only determines whether the vehicle's electric drive system can meet the transportation torque and power requirements, which belongs to point condition analysis. There is a lack of analysis and judgment on the stability of performance during operation, such as shifting logic and speed range. This often leads to power and gear mismatch during vehicle operation, resulting in insufficient power or insufficient electric braking force, affecting the safety and efficiency of vehicle transportation. The traditional selection method can only judge whether the maximum capacity of the electric drive system meets the requirements, and cannot evaluate the stability and energy efficiency of performance during operation. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a performance analysis method for the electric transmission system of a pure electric mining dump truck, to perform process performance verification on the electric transmission system of the vehicle selection, to develop a high-efficiency electric transmission shifting logic, to add line condition considerations on the basis of traditional point condition selection, and to ensure that the use of the electric transmission system meets the application requirements.

[0005] In order to solve the above technical problems, the technical solution of the present invention is: a method for analyzing the performance of an electric transmission system of a pure electric mining dump truck, comprising the following steps: Step 1, check the selection results of electric transmission components: check the maximum traction\braking power and maximum traction\braking torque of the vehicle motor according to the road conditions and vehicle parameters of the vehicle, and draw the running characteristic climbing resistance curve fz(v) and heavy load downhill force curve f'z(v); Step 2, traction shift logic performance analysis: According to the vehicle running road conditions, match the lowest gear of the gearbox under the maximum torque of the gearbox climbing, and complete the traction climbing gearbox shift performance analysis, as follows: (2.1) Draw the traction characteristic curve f(v) of the electric drive system according to the recommended shift speed n of the x-gear transmission and the motor characteristic curve; (2.2) The traction characteristic curve f(v) and the climbing resistance curve fz(v) are cross-analyzed, and the climbing gear shift logic is determined according to the principle that the traction force of the electric transmission system ftraction(v)=f(v)≥1.25fz(v); Step 3, brake shift logic performance analysis: According to the vehicle running road conditions, match the gearbox's highest gear position under the gearbox's maximum torque on downhill, and complete the gearbox's downhill shift performance analysis, as follows: (3.1) Draw the braking characteristic curve f'(v) of the electric transmission system according to the recommended shift speed n of the x-speed gearbox and the motor characteristic curve f(n); (3.2) The braking characteristic curve f'(v) and the heavy load downhill force curve f'z(v) are cross-analyzed. According to the braking force f of the electric transmission system 制动 The downhill braking gear shift logic is determined by the principle of resistance (v)=f'(v)≥f'z(v); (3.3) According to the braking characteristic curve f 制动 (v) draw the vehicle downhill braking power curve W(n); W(n)=f 制动 (v).v (3.4) Draw the battery temperature-feedback power relationship curve W(t) based on the battery temperature-charging current characteristic curve I(t); W(t)=I(t).U (3.5) Cross-analysis of vehicle downhill braking power curve W(n) and battery temperature-feedback power relationship curve W(t); when W(n)>W(t), the electric transmission downhill braking power is W 制动 (v)=W(t); when W(n)<W(t), the downhill braking power of the electric transmission is W 制动 (v) = W (n); (3.6) According to the electric transmission downhill braking power W 制动 (v) Determine the braking characteristic curve f' 制动 (v); (3.7) Braking characteristic curve f' 制动 (v) Interactive analysis with the heavy-load downhill force curve f'z(v), taking the highest gear as the ideal gear and determining the gear shifting logic; Step 4, traction efficiency analysis: According to the gear shifting logic determined in step 2, calculate the commonly used speed range of each gear and compare it with the motor efficiency map to verify that the motor efficiency is not less than 90%; Step 5, braking performance analysis: According to the gear shifting logic determined in step (3.7), calculate the commonly used speed range of each gear and compare it with the motor efficiency map to verify that the motor efficiency is not less than 90%.

[0006] Compared with the prior art, the present invention has the following beneficial effects: Conduct process performance verification on the electric transmission system selected for the vehicle, develop a highly efficient electric transmission shifting logic, and add line condition considerations on the basis of traditional point condition selection to ensure that the use of the electric transmission system meets the application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 This is the traction climbing resistance curve fz(v).

[0008] Figure 2 This is the heavy load downhill force f'z(v) curve.

[0009] Figure 3 f 牵引 (v) Value cross analysis diagram.

[0010] Figure 4 f 制动 (v) Value cross analysis diagram.

[0011] Figure 5 This is the motor efficiency map.

[0012] Figure 6 This is the motor efficiency map. DETAILED DESCRIPTION

[0013] The present invention will be further described below in conjunction with the accompanying drawings.

[0014] A method for analyzing the performance of an electric transmission system of a pure electric mining dump truck comprises the following steps: Step 1: Check the selection results of electric transmission components: Check the maximum traction and braking power of the vehicle motor and the maximum traction and braking torque of the motor according to the road conditions and vehicle parameters (slope, resistance coefficient, transmission ratio, etc.). Figure 1 , 2 As shown, the running characteristic climbing resistance curve fz(v) and the heavy load downhill force curve f'z(v) are drawn; Step 2, traction shift logic performance analysis: According to the vehicle running road conditions, match the lowest gear of the gearbox under the maximum torque of the gearbox climbing, and complete the traction climbing gearbox shift performance analysis, as follows: (2.1) Draw the traction characteristic curve f(v) of the electric drive system according to the recommended shift speed n (generally 2700r / min) of the x-speed gearbox and the motor characteristic curve; (2.2) Cross analysis of the traction characteristic curve f(v) and the climbing resistance curve fz(v), as shown in Figure 3 As shown, the gear shifting logic for climbing gears is determined according to the principle that the traction force of the electric transmission system ftraction(v)=f(v)≥1.25fz(v); Step 3, brake shift logic performance analysis: According to the vehicle running road conditions, match the gearbox's highest gear position under the gearbox's maximum torque on downhill, and complete the gearbox's downhill shift performance analysis, as follows: (3.1) Draw the braking characteristic curve f'(v) of the electric transmission system according to the recommended shift speed n (generally 2700r / min) of the x-speed gearbox and the motor characteristic curve f(n); (3.2) If Figure 4 As shown in the figure, the braking characteristic curve f'(v) and the heavy load downhill force curve f'z(v) are cross-analyzed. According to the braking force f of the electric transmission system 制动 The downhill braking gear shift logic is determined by the principle of resistance (v)=f'(v)≥f'z(v); (3.3) According to the braking characteristic curve f 制动 (v) draw the vehicle downhill braking power curve W(n); W(n)=f 制动 (v).v (3.4) Draw the battery temperature-feedback power relationship curve W(t) based on the battery temperature-charging current characteristic curve I(t); W(t)=I(t).U (3.5) Cross-analysis of vehicle downhill braking power curve W(n) and battery temperature-feedback power relationship curve W(t); when W(n)>W(t), the electric transmission downhill braking power is W 制动 (v)=W(t); when W(n)<W(t), the downhill braking power of the electric transmission is W 制动 (v) = W (n); (3.6) According to the electric transmission downhill braking power W 制动 (v) Determine the braking characteristic curve f' 制动 (v); (3.7) Braking characteristic curve f' 制动 (v) Interactive analysis with the heavy-load downhill force curve f'z(v), taking the highest gear as the ideal gear and determining the gear shifting logic; Step 4, traction efficiency analysis: Figure 5 As shown, according to the gear shifting logic determined in step 2, the commonly used speed range of each gear is calculated and compared with the motor efficiency map to verify that the motor efficiency is not less than 90%; Step 5, braking performance analysis: Figure 6 As shown, according to the shifting logic determined in step (3.7), the commonly used speed range of each gear is calculated and compared with the motor efficiency map to verify that the motor efficiency is not less than 90%.

Claims

1. A method for analyzing the performance of an electric transmission system of a pure electric mining dump truck, characterized in that: The following steps are involved: Step 1, check the selection results of electric transmission components: check the maximum traction\braking power and maximum traction\braking torque of the vehicle motor according to the road conditions and vehicle parameters of the vehicle, and draw the running characteristic climbing resistance curve fz(v) and heavy load downhill force curve f'z(v); Step 2, traction shift logic performance analysis: According to the vehicle running road conditions, match the lowest gear of the gearbox under the maximum torque of the gearbox climbing, and complete the traction climbing gearbox shift performance analysis, as follows: (2.1) Draw the traction characteristic curve f(v) of the electric drive system according to the recommended shift speed n of the x-gear transmission and the motor characteristic curve; (2.2) The traction characteristic curve f(v) and the climbing resistance curve fz(v) are cross-analyzed, and the climbing gear shift logic is determined according to the principle that the traction force of the electric transmission system ftraction(v)=f(v)≥1.25fz(v); Step 3, brake shift logic performance analysis: According to the vehicle running road conditions, match the gearbox's highest gear position under the gearbox's maximum torque on downhill, and complete the gearbox's downhill shift performance analysis, as follows: (3.1) Draw the braking characteristic curve f'(v) of the electric transmission system according to the recommended shift speed n of the x-speed gearbox and the motor characteristic curve f(n); (3.2) The braking characteristic curve f'(v) and the heavy load downhill force curve f'z(v) are cross-analyzed. According to the braking force f of the electric transmission system 制动 The downhill braking gear shift logic is determined by the principle of resistance (v)=f'(v)≥f'z(v); (3.3) According to the braking characteristic curve f 制动 (v) draw the vehicle downhill braking power curve W(n); W(n)=f 制动 (v).v (3.4) Draw the battery temperature-feedback power relationship curve W(t) based on the battery temperature-charging current characteristic curve I(t); W(t)=I(t).U (3.5) Cross-analysis of vehicle downhill braking power curve W(n) and battery temperature-feedback power relationship curve W(t); when W(n)>W(t), the electric transmission downhill braking power is W 制动 (v)=W(t); when W(n)<W(t), the downhill braking power of the electric transmission is W 制动 (v) = W (n); (3.6) According to the electric transmission downhill braking power W 制动 (v) Determine the braking characteristic curve f' 制动 (v); (3.7) Braking characteristic curve f' 制动 (v) Interactive analysis with the heavy-load downhill force curve f'z(v), taking the highest gear as the ideal gear and determining the gear shifting logic; Step 4, traction efficiency analysis: According to the gear shifting logic determined in step 2, calculate the commonly used speed range of each gear and compare it with the motor efficiency map to verify that the motor efficiency is not less than 90%; Step 5, braking performance analysis: According to the gear shifting logic determined in step (3.7), calculate the commonly used speed range of each gear and compare it with the motor efficiency map to verify that the motor efficiency is not less than 90%.

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