Operating condition design method for reliability verification of dual-motor system of p13-configuration electric drive transmission and reliability testing method for dual-motor system of p13-configuration electric drive transmission

Abstract

An operating condition design method for reliability verification of a dual-motor system of a P13-configuration electric drive transmission and a reliability testing method for a dual-motor system of a P13-configuration electric drive transmission, which meet the development, usage, and safety requirements of electric drive transmissions while shortening the product development cycle. The design method comprises: on the basis of structural principles and usage modes of P13-configuration electric drive transmissions, and considering also motor verification coverage scenarios and whole-vehicle road scenarios, designing dual-motor system reliability verification operating conditions which use P3 motor operating conditions as the main conditions, complemented by P1 motor operating conditions; and combining product performance design parameters and whole-vehicle control logic to form an initial operating condition test table for the dual-motor system reliability verification operating conditions (S101); and adjusting the running time of each operating condition in the initial operating condition test table, so as to obtain a final required operating condition test table for dual-motor system reliability verification and the number of operating condition cycles for the dual-motor system reliability verification (S102).

Description

Design method and reliability test method of reliability verification working condition of dual-motor system of P13 configuration electric drive transmission Technical Field

[0001] The embodiments of the present application relate to the field of testing of P13 configuration electric drive transmissions, specifically a design method and reliability testing method for reliability verification working conditions of a dual-motor system of a P13 configuration electric drive transmission. Background Art

[0002] The P13 configuration is currently a common hybrid vehicle technology, and various companies are actively developing it. The two motors integrated in the P13 completed their own verification projects during the DV development phase. After the dual-motor integrated transmission forms the P13 hybrid electric transmission, the various components coordinate their functions in terms of circuits, oil circuits, shaft gears, torque transmission, and controller control. The function and stability of the dual-motor and controller-plus-transmission motor system directly impacts the quality of the hybrid transmission, the user experience, and driving safety. Currently, OEMs have conducted limited research on the reliability verification of the motor system combination for the P13 electric transmission. To better develop the P13 electric transmission and shorten the product development cycle, it is necessary to conduct reliability testing and research on the P13 electric transmission motor system.

[0003] Regarding the reliability verification of the dual-motor system of the P13 configuration, in the currently known reliability test of the electric drive transmission motor system of the P13 structure, the durability test method and device of the dual-motor hybrid transmission (CN115575116A) mainly provides a general idea of ​​bench testing of the electric drive transmission with a dual-motor, and introduces the use of speed targets and wheel-side torque targets to carry out bench testing. Its object structure is different from that of the present application, and there is no reliability verification method for the dual-motor system. A drive motor system reliability test method and device (CN108983095A) mainly provides a method for collecting the work spectrum of the motor system according to the road usage of the vehicle, calculating the driving power and feeding power of the motor, and further determining the speed, torque, and time before conducting a verification method for the motor reliability on the bench. It mainly establishes the work conversion between the motor in the use of the whole vehicle and the bench verification, simplifies the complex and changeable working conditions of the motor system in the whole vehicle, and facilitates bench verification control. Its content does not involve the operating condition control of a single motor and the overall functional verification of the dual-motor and transmission system, and requires a complete vehicle function completion stage, and cannot be used for the early development of electric drive transmission projects.

[0004] Summary of the Invention

[0005] The present application provides a design method and a reliability testing method for the reliability verification working conditions of the dual-motor system of a P13 configuration electric drive transmission, which is used to perform reliability testing on the dual-motor system of a P13 configuration hybrid electric drive transmission to meet the development, use and safety requirements of the electric drive transmission while shortening the product development cycle.

[0006] The technical solution of this application is:

[0007] This application provides a design method for reliability verification working conditions of a dual-motor system of a P13 configuration electric drive transmission. The P13 configuration electric drive transmission includes a dual-motor system and other component systems. The other component systems include gears, shaft systems, and bearings, including:

[0008] Based on the structural principles and usage of the P13 configuration electric drive transmission, combined with the motor verification coverage scenarios and vehicle road scenarios, a dual-motor system reliability verification operating condition is designed, with the P3 motor operating condition as the main line and the P1 motor operating condition in coordination. The initial operating condition test table for the dual-motor system reliability verification operating condition is formed by combining the product performance design parameters and the vehicle control logic.

[0009] Adjust the operating time of each working condition in the initial working condition test table to obtain the final required dual-motor system reliability verification working condition test table and the number of working condition cycles for the dual-motor system reliability verification.

[0010] Optionally, the step of adjusting the operating time of each operating condition in the initial operating condition test table to obtain the final required dual-motor system reliability verification operating condition test table and the number of operating condition cycles for the dual-motor system reliability verification includes:

[0011] The P13 configuration electric drive transmission is tested based on the design mileage and initial verification operating condition test table of the P13 configuration electric drive transmission. The Miner linear damage accumulation theory, the design mileage of the vehicle, the number of alternating load cycles of the P13 configuration electric drive transmission for torque, and the 13 configuration electric drive transmission's load capacity for the rate of change of speed and torque are used to adjust the operating time of each operating condition in the initial operating condition test table until the other parts and systems of the P13 configuration electric drive transmission meet the reliability strength requirements of the design mileage of the vehicle and other parts and systems meet the load level of normal use, and the final required dual-motor system reliability verification operating condition test table and the number of operating condition cycles for dual-motor system reliability verification are obtained.

[0012] Optionally, the initial operating condition test table includes a first type of operating condition related to product design performance parameters and a second type of operating condition related to normal vehicle use. The parameters in the first and second types of operating conditions include: P1 motor torque, P3 motor torque, P1 motor speed, P3 motor speed, duration, and cumulative time; the cumulative time refers to the total test duration in a single reliability verification cycle;

[0013] The steps for forming an initial operating condition test table for the dual-motor system reliability verification operating conditions by combining product performance design parameters and vehicle control logic include:

[0014] Based on the product performance design parameters of the P13 configuration electric drive transmission, determine the parameter boundaries of the P1 motor torque, P3 motor torque, P1 motor speed, and P3 motor speed in the first operating condition; combine the overall cooling capacity, stator temperature, and the load-bearing capacity of other component systems of the P13 configuration electric drive transmission to determine the parameter boundaries of the duration and cumulative time;

[0015] Based on the vehicle control logic, the parameter boundaries of P1 motor torque, P3 motor torque, P1 motor speed, and P3 motor speed in the second type of operating condition are determined; combined with the overall cooling capacity, stator temperature, and load-bearing capacity of the P13 configuration electric drive transmission and other parts and systems, the parameter boundaries of duration and cumulative time are determined.

[0016] Optionally, the first type of operating conditions includes: P3 motor design target operating conditions;

[0017] In the design target operating condition A of the P3 motor: the boundary of the P3 motor torque is determined according to the peak torque of the P3 motor, the boundary of the P3 motor speed is determined according to the turning speed of the P3 motor, the P1 motor torque and the P1 motor speed are 0, and the duration is determined according to the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the P3 motor continuously outputs the peak torque.

[0018] Optionally, the first type of working condition further includes: motor system coupling working condition B; motor system coupling working condition B includes three coupling working conditions;

[0019] In the first coupling operating condition B1: the limit of the P3 motor torque is determined by the rated torque of the P3 motor, the limit of the P3 motor speed is determined by the rated speed of the P3 motor, the limit of the P1 motor torque is determined by the peak power generation torque of the P1 motor, and the limit of the P1 motor speed is determined by the turning speed of the P1 motor; the duration is determined by the time required for the stator temperature of the P1 motor to rise to the upper limit temperature when the P1 motor outputs the peak power generation torque;

[0020] In the second coupling condition B2: the P3 motor torque limit is determined by the P3 motor's rated torque, the P3 motor speed limit is determined by the P3 motor's rated speed, the P1 motor torque limit is determined by the P1 motor's rated power generation torque, the P1 motor speed limit is determined by the P1 motor's rated speed, and the duration is determined by the cooling capacity of the electric drive transmission.

[0021] In the third coupling working condition B3: the boundary of the P3 motor torque is determined according to the continuous torque at the maximum operating speed of the P3 motor, the boundary of the P3 motor speed is determined according to the maximum operating speed of the P3 motor, the boundary of the P1 motor torque is determined according to the continuous torque at the maximum operating speed of the P1 motor, the boundary of the P1 motor speed is determined according to the maximum operating speed of the P1 motor, and the duration is pre-set.

[0022] Optionally, the second type of working conditions includes: common vehicle working conditions C,

[0023] In the common operating condition C of the whole vehicle: the limit of the P3 motor torque is determined according to the P3 motor rated torque * preset value, the P3 motor speed is determined according to the preset motor speed, the limit of the P1 motor torque is determined according to the normal power generation torque of the P1 motor, the limit of the P1 motor speed is determined according to the normal power generation speed of the P1 motor, and the duration is pre-set.

[0024] Optionally, the first type of working condition further includes: a P3 motor feeding design target working condition D, where the P3 motor feeding design target working condition D includes three feeding design target working conditions;

[0025] The P1 motor torque, P1 motor speed, and P1 motor duration in the three feed design target operating conditions are 0;

[0026] In the first power feeding design target operating condition D1: the boundary value of the P3 motor torque is determined by the power feeding rated torque of the P3 motor, the boundary value of the P3 motor speed is determined by the rated speed of the P3 motor, and the duration is determined by the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the power feeding rated torque is output;

[0027] In the second power feeding design target operating condition D2: the boundary value of the P3 motor torque is determined by the P3 motor power feeding peak torque, the boundary value of the P3 motor speed is determined by the P3 motor turning speed, and the duration is determined by the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the peak torque is fed;

[0028] In the third power feeding design target operating condition D3: the boundary value of the P3 motor torque is determined according to the P3 motor power feeding rated torque, the boundary value of the P3 motor speed is determined according to the P3 motor rated speed, and the duration is determined according to the cooling capacity of the electric drive transmission.

[0029] Optionally, the first type of operating condition also includes: P1 motor design target operating condition E;

[0030] In the design target operating condition E of the P1 motor, the P3 motor torque, P3 motor speed and P3 motor duration are 0, the boundary of the P1 motor torque is determined according to the P1 motor rated torque, the boundary of the P1 motor speed is determined according to the P1 motor rated speed, and the duration is pre-set.

[0031] This application also provides a reliability testing method for a dual-motor system of a P13 configuration electric drive transmission, including:

[0032] Test preparation: Install the P13 electric drive transmission on the test bench according to the vehicle status;

[0033] Test access inspection: including product status confirmation, test version data inspection, test control boundary condition confirmation, and test bench on-site safety inspection;

[0034] Bench debugging control and motor zero position learning:

[0035] Initial performance test: Before the dual-motor system reliability test, the P1 and P3 motors of the P13 configuration electric drive transmission are tested for external characteristic speed and torque.

[0036] Working condition operation: The working condition is obtained by adopting the design method of the reliability verification working condition of the dual-motor system of the P13 configuration electric drive transmission mentioned above, and the dual-motor system of the P13 configuration electric drive transmission is subjected to cyclic working condition operation according to the obtained working condition cycle number and the dual-motor system reliability verification working condition test table; wherein, in the cyclic working condition operation, the first 80% of the cyclic working conditions are operated according to the designed rated voltage platform, 80%-90% of the cyclic working conditions are operated according to the designed minimum working voltage platform, and 90%-100% of the cyclic working conditions are operated according to the designed maximum working voltage platform;

[0037] Performance retest: After the dual-motor system reliability test, the P1 and P3 motors of the P13 configuration electric drive transmission are tested for external characteristic speed and torque;

[0038] Post-test analysis.

[0039] Optionally, in the test preparation step, the P13 configuration electric drive transmission is installed on the test bench according to the following process:

[0040] Use the No. 3 test bench drive motor to simulate the vehicle engine to provide energy input for the P13 configuration electric drive transmission. Use the No. 1 test bench load motor and the No. 2 test bench load motor to simulate the vehicle wheel end load of the P13 configuration electric drive transmission. Use the motor controller PEU to control the functional operation of the P1 motor and P3 motor of the P13 configuration electric drive transmission. Connect the No. 1 test bench load motor, the No. 2 test bench load motor, the motor controller PEU and the battery simulator to the test bench respectively, and connect the battery simulator and the motor controller PEU.

[0041] Optionally, during the reliability test of the dual-motor system, the clutch of the P13 configuration electric drive transmission is not engaged throughout the entire process.

[0042] Optionally, during the performance initial test and performance retest steps,

[0043] When performing external characteristic torque test on P1 motor, only the feeding torque part of P1 motor is tested. When performing external characteristic torque test on P3 motor, only the driving torque and feeding torque parts of P3 motor are tested.

[0044] When performing external characteristic speed tests on P1 and P3 motors, the speed is 500 rpm, up to the maximum operating speed of the corresponding motor. The speed points when performing external characteristic speed tests on P1 and P3 motors include the rated speed and turning speed of the corresponding motor;

[0045] During the initial performance test and re-test, it is necessary to ensure that the boundary conditions of the test bench's lubricating oil, coolant, lubrication flow, and voltage platform are within the product specifications of the P13 configuration electric drive transmission.

[0046] Optionally, in the test bench debugging control step, it is necessary to first set the coolant temperature and lubricating oil temperature of the test bench according to the lubrication and cooling requirements of the P13 configuration electric drive transmission, and set the oil pump speed of the test bench according to the lubrication flow requirements of the P13 configuration electric drive transmission; after completing the alarm limit setting of the coolant temperature, lubricating oil temperature and oil pump speed, set the No. 1 test bench load motor, No. 2 test bench load motor and No. 3 test bench drive motor to adopt the speed / torque mode, and the speed of the No. 1 test bench load motor and No. 2 test bench load motor is set according to the P3 motor speed and converted according to the shaft speed ratio of the P13 configuration electric drive transmission.

[0047] Optionally, in the operating condition step, after completing 100% of the cycle operating condition operation, the P1 motor and P3 motor of the P13 configuration electric drive transmission are controlled to operate for a preset time at their respective rated operating voltage, maximum operating speed, and rated power.

[0048] The beneficial effects of this application are:

[0049] In this embodiment, based on the structural principle of the P13 configuration electric drive transmission, combined with the product design parameters and the actual operating conditions during the vehicle's use, and with the reliability strength of the vehicle's design service life as the goal, a reliability test condition for the P13 configuration electric drive transmission dual-motor system is designed. Under the design conditions, the Miner linear damage principle is used to confirm the reliability time of the main components of the electric drive transmission (shaft system, bearings), thereby forming a P13 configuration electric drive transmission dual-motor reliability test method. Through this test, the functional logic of the motor system software, the coupling conditions of the dual-motor system, and the reliability of the main components of the electric drive transmission can be verified at an early stage of project development. It is a very advantageous verification method after the dual motors and transmission are integrated. It is an important parameter means in the product development process of the P13 configuration electric drive transmission. It achieves the effect of overall verification and reducing the number of verification samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] FIG1 is a schematic diagram of the test bench layout of the P13 configuration electric drive transmission in this embodiment;

[0051] FIG2 is a schematic diagram of torque operating conditions during a dual-motor reliability test of a P13 configuration electric drive transmission in this embodiment;

[0052] FIG3 is a schematic diagram of the speed operating conditions during the dual-motor reliability test of the P13 configuration electric drive transmission in this embodiment;

[0053] Figure 4 is a schematic diagram of the SN curve;

[0054] FIG5 is a schematic diagram of the design method in this embodiment;

[0055] FIG6 is a schematic diagram of the testing method in this embodiment. DETAILED DESCRIPTION

[0056] The following will describe the embodiments of the present application with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand the other advantages and effects of the present application from the contents disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for the purpose of illustrating the present application and are not intended to limit the scope of protection of the present application.

[0057] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. Therefore, the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0058] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present application. However, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details.

[0059] The present application relates to a control test scheme, operating condition and test boundary design, and test implementation process for reliability verification of a dual-motor system of a P13 configuration electric drive transmission.

[0060] As shown in Figure 1, the control test system primarily consists of a P13 electric transmission 12, a test bench, and its control system. The P1 motor 1, clutch 4, P3 motor 3, and transmission 3 form the P13 electric transmission 12. Transmission 2 is connected to test bench load motor 8 (No. 1) via axle 10, which in turn is connected to test bench load motor 7 (No. 2) via axle 9. The PEU (motor controller) 5 serves as the control module for the P13 electric transmission 12. The test bench also includes test bench load motors 8 (No. 1), 7 (No. 2), a test bench 11, temperature control equipment, and a battery simulator 6. The test bench 11 should also be equipped with a data acquisition system capable of accurately measuring and collecting necessary test parameters such as temperature, pressure, and speed. The test bench control system should be able to communicate with the electric transmission product control unit (PEU).

[0061] As shown in FIG5 , in this embodiment, the aforementioned control test system is used to implement the design of reliability verification working conditions for the dual-motor system of the P13 configuration electric drive transmission. The specific design method includes:

[0062] S101: Based on the structural principles and usage of the P13 configuration electric drive transmission, combined with motor verification coverage scenarios and vehicle road scenarios, a dual-motor system reliability verification operating condition is designed, with the P3 motor operating condition as the main line and the P1 motor operating condition as the auxiliary. The initial operating condition test table for the dual-motor system reliability verification operating condition is formed by combining product performance design parameters and vehicle control logic.

[0063] S102 , adjusting the operating time of each operating condition in the initial operating condition test table to obtain the final required dual-motor system reliability verification operating condition test table and the number of operating condition cycles for the dual-motor system reliability verification.

[0064] S102 is specifically to test the P13 configuration electric drive transmission based on the design mileage and initial verification working condition test table of the P13 configuration electric drive transmission, and use the miner linear damage accumulation theory, the design mileage of the whole vehicle, the number of alternating load cycles of the P13 configuration electric drive transmission for torque, and the 13 configuration electric drive transmission's carrying capacity for the rate of change of speed and torque, to adjust the operating time of each working condition in the initial working condition test table until the other parts and systems of the P13 configuration electric drive transmission meet the reliability strength requirements of the design mileage of the whole vehicle and the other parts and systems meet the normal use load level, and obtain the final required dual-motor system reliability verification working condition test table and the number of working condition cycles for the dual-motor system reliability verification. Specifically, in combination with Figures 2 and 3, the design process of the dual-motor system reliability verification working condition in this implementation is as follows:

[0065] 1.P13 motor system test plan

[0066] The P1 motor 1 (GM motor) of the P13 configuration electric drive transmission 12 is located at the front end of the transmission 2 and is connected to the engine. During use, it drags the engine to rotate and ignite, acting as the engine starting motor. During normal engine operation, the P1 motor 1 uses the energy feed (negative work) provided by the engine to convert it into electrical energy and store it in the battery or provide it to the P3 motor 3 for use. When the entire vehicle requires a large torque, the clutch 4 engages, and the engine output torque is transmitted to the transmission shaft system through the clutch for assistance. At this time, the P1 motor 1 follows the engine to idle. The P3 motor 3 (TM motor) is directly connected to the transmission shaft system, using electrical energy to output torque to provide the main power source (positive work) for vehicle travel. At the same time, during vehicle braking, it uses vehicle braking energy recovery to convert kinetic energy into electrical energy (negative work) and input it back into the battery. The above is the basic working principle of the P13 configuration electric drive transmission, and its function is controlled by the electric drive transmission controller (PEU).

[0067] The main function of the P1 motor 1 in the P13 configuration electric drive transmission is to use the engine energy to generate electricity (negative work), and the main function of the P3 motor 3 is to provide power for the vehicle (positive work) and recover energy during braking (negative work). According to the application scenario of the dual-motor system in the whole vehicle, the overall function and reliability of the motor, controller, transmission shaft system and accessory system are comprehensively verified, and the verification feasibility and shortening of the verification cycle are taken into account. Combined with the working conditions of the samples of each part, the working mode of the bench drive motor and the load motor, and under the premise of following the design basis and control strategy of the electric drive transmission, the reliability verification method of the dual-motor system is sorted out. The drive motor assembly bench-level verification is adopted, as shown in Figure 1. The dual motors carry out working conditions at the same time. According to the control logic of the whole vehicle, the dual motors work in coordination, and the test boundary conditions refer to the whole vehicle level. The No. 3 test bench drive motor simulated the vehicle engine and provided energy input. The test was controlled using a speed / torque mode, combined with verification operating conditions to assess the reliability of the P1 motor. The No. 1 and No. 2 test bench load motors simulated the vehicle wheel loads. The test was controlled using a speed / torque mode, combined with verification operating conditions to assess the reliability of the P3 motor. The PEU motor controller controlled the functional operation of both motors, combining the vehicle control logic and the dual-motor verification operating conditions to complete the verification. The entire verification process assessed the reliability of the motor system, without requiring engine power to be transmitted to the transmission shafting. Therefore, clutch 4 was not engaged at all.

[0068] 2. Design of the dual-motor system verification operating condition for the P13 electric transmission

[0069] According to the motor design standard of P13 configuration electric drive transmission, the performance parameters of P1 and P3 motor products have been determined in the design process: rated power P N , rated torque T N , peak power PP , peak torque T P , Maximum operating speed n max The following common parameters can be calculated based on relevant performance parameters:

[0070] T C -Continuous torque at maximum operating speed:

[0071]

[0072] n t - Turning speed (the highest speed at which the motor system can output peak torque):

[0073] The P1 motor operating condition design is based on the P1 input end design load torque, combined with the engine control strategy to determine the input torque for power generation condition verification. The P3 motor operating condition design is based on the P3 input end design load torque, combined with road spectrum simulation data to determine the input torque for direct drive and energy recovery verification. In the application scenario, the P3 motor system operating condition is more complex than the P1, so the dual-motor system reliability verification condition design is based on the P3 motor operating condition, with the P1 motor operating condition as the main line. According to the motor verification coverage scenario and the vehicle road scenario, the dual-motor system reliability verification condition of the P13 configuration electric drive transmission is carried out according to the following plan:

[0074] (1) Product design performance parameter working conditions (i.e. the first type of working conditions):

[0075] (2) Normal operating conditions of the vehicle (i.e., the second type of operating conditions):

[0076] (3) Determine the parameter operating boundaries of the dual-motor system reliability verification conditions based on product design parameters. When determining the parameter operating boundaries, the following should be considered:

[0077] ① The peak torque operation duration of the motor is mainly affected by the motor stator temperature. This factor determines the peak torque duration of the P1 motor and the P3 motor;

[0078] ② The cooling capacity of the electric drive transmission (mainly the cooling capacity of the stator) affects the operating time of the cooling condition after the peak torque condition;

[0079] ③ The controller power control parameters can meet the use of two motors, that is, the output power of the P1 motor and the P3 motor ≤ the output power of the motor controller PEU;

[0080] ④ The torque output slope of the hybrid transmission shaft system is smaller than that of pure electric vehicles. The torque output slope of the hybrid transmission should take into account the bearing capacity of the gear shaft system. According to the simulation analysis of the road spectrum of vehicle verification, the torque output slope of the hybrid electric drive transmission is less than 40N.m / s, and the speed change is within 500rpm / s.

[0081] [Corrected 29.02.2024 according to Rule 26] Based on the coupling working principle and performance parameters of P1 motor 1, P3 motor 3, and motor controller PEU, and in accordance with the boundary conditions of the entire machine, the required working conditions are combined and sorted to obtain the motor system reliability working conditions of the P13 configuration electric drive transmission as shown in Table 1 below: [0081.1] [Corrected 29.02.2024 in accordance with Rule 26] [0081.2] [Corrected 29.02.2024 in accordance with Rule 26] [0081.3] [Corrected 29.02.2024 in accordance with Rule 26] [0081.4] [Corrected 29.02.2024 in accordance with Rule 26] [0081.5] [Corrected 29.02.2024 in accordance with Rule 26]

[0082] Table 1

[0083] In summary, based on the product performance design parameters of the P13 configuration electric drive transmission, the parameter boundaries of the P1 motor torque, P3 motor torque, P1 motor speed, and P3 motor speed in the first operating condition are determined; the parameter boundaries of the duration and cumulative time are determined by combining the overall cooling capacity, stator temperature, and the load-bearing capacity of other component systems of the P13 configuration electric drive transmission;

[0084] Based on the vehicle control logic, the parameter boundaries of P1 motor torque, P3 motor torque, P1 motor speed, and P3 motor speed in the second type of operating condition are determined; combined with the overall cooling capacity, stator temperature, and load-bearing capacity of the P13 configuration electric drive transmission and other parts and systems, the parameter boundaries of duration and cumulative time are determined.

[0085] With reference to the following tables, in this embodiment, in the target operating condition A of the P3 motor design: the boundary of the P3 motor torque is determined according to the peak torque of the P3 motor, the boundary of the P3 motor speed is determined according to the turning speed of the P3 motor, the P1 motor torque and the P1 motor speed are 0, and the duration is determined according to the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the P3 motor continuously outputs the peak torque.

[0086] The first type of working conditions also includes: motor system coupling working condition B; motor system coupling working condition B includes three coupling working conditions;

[0087] In the first coupling operating condition B1: the limit of the P3 motor torque is determined by the rated torque of the P3 motor, the limit of the P3 motor speed is determined by the rated speed of the P3 motor, the limit of the P1 motor torque is determined by the peak power generation torque of the P1 motor, and the limit of the P1 motor speed is determined by the turning speed of the P1 motor; the duration is determined by the time required for the stator temperature of the P1 motor to rise to the upper limit temperature when the P1 motor outputs the peak power generation torque;

[0088] In the second coupling condition B2: the P3 motor torque limit is determined by the P3 motor's rated torque, the P3 motor speed limit is determined by the P3 motor's rated speed, the P1 motor torque limit is determined by the P1 motor's rated power generation torque, the P1 motor speed limit is determined by the P1 motor's rated speed, and the duration is determined by the cooling capacity of the electric drive transmission.

[0089] In the third coupling working condition B3: the boundary of the P3 motor torque is determined according to the continuous torque at the maximum operating speed of the P3 motor, the boundary of the P3 motor speed is determined according to the maximum operating speed of the P3 motor, the boundary of the P1 motor torque is determined according to the continuous torque at the maximum operating speed of the P1 motor, the boundary of the P1 motor speed is determined according to the maximum operating speed of the P1 motor, and the duration is pre-set.

[0090] The second type of operating conditions includes: common operating conditions C for the whole vehicle. In common operating conditions C for the whole vehicle: the boundary of the P3 motor torque is determined according to the P3 motor rated torque * preset value, the P3 motor speed is determined according to the preset motor speed, the boundary of the P1 motor torque is determined according to the conventional power generation torque of the P1 motor, the boundary of the P1 motor speed is determined according to the conventional power generation speed of the P1 motor, and the duration is pre-set.

[0091] The first type of working conditions also includes: P3 motor feeding design target working condition D, P3 motor feeding design target working condition D includes three feeding design target working conditions;

[0092] The P1 motor torque, P1 motor speed, and P1 motor duration in the three feed design target operating conditions are 0;

[0093] In the first power feeding design target operating condition D1: the boundary value of the P3 motor torque is determined by the power feeding rated torque of the P3 motor, the boundary value of the P3 motor speed is determined by the rated speed of the P3 motor, and the duration is determined by the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the power feeding rated torque is output;

[0094] In the second power feeding design target operating condition D2: the boundary value of the P3 motor torque is determined by the P3 motor power feeding peak torque, the boundary value of the P3 motor speed is determined by the P3 motor turning speed, and the duration is determined by the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the peak torque is fed;

[0095] In the third power feeding design target operating condition D3: the boundary value of the P3 motor torque is determined according to the P3 motor power feeding rated torque, the boundary value of the P3 motor speed is determined according to the P3 motor rated speed, and the duration is determined according to the cooling capacity of the electric drive transmission.

[0096] The first type of operating conditions also includes: P1 motor design target operating condition E; in P1 motor design target operating condition E: P3 motor torque, P3 motor speed and P3 motor duration are 0, the boundary of P1 motor torque is determined according to the P1 motor power generation rated torque, the boundary of P1 motor speed is determined according to the P1 motor rated speed, and the duration is pre-set.

[0097] The sources of each working condition are as follows:

[0098] [Corrected 29.02.2024 in accordance with Article 26]

[0099] [Corrected 29.02.2024 according to Rule 26] Operating Condition B: Motor System Coupling Condition

[0100] [Corrected 29.02.2024 in accordance with Article 26]

[0101] [Corrected 29.02.2024 in accordance with Article 26]

[0102] [Corrected 29.02.2024 according to Rule 26] Working Condition C: Common working condition of the whole vehicle [0102.1] [Corrected 29.02.2024 in accordance with Rule 26] [0102.2][Corrected 29.02.2024 according to Rule 26] Working Condition D: P3 motor feed design target working condition [0102.3] [Corrected 29.02.2024 in accordance with Rule 26] [0102.4] [Corrected 29.02.2024 according to Rule 26] Operating Condition E: P1 motor design target operating condition [0102.5] [Corrected 29.02.2024 in accordance with Rule 26]

[0103] (4) Determination of the number of cycles for reliability verification:

[0104] The reliability verification of the dual-motor system is based on the assembly and verification of the electric drive transmission. The test verification time is determined by using Miner linear damage theory under the above design conditions to determine the product shaft system, bearings, gears and other parts.

[0105] The fatigue life of the system is then used to select the shortest operation time of the electric transmission from multiple fatigue lives, but it should meet the design mileage and service life standards of the vehicle (usually 10 years and 300,000 kilometers).

[0106] ① Linear damage accumulation theory: The fatigue life of electric drive transmission bearings, gears, etc. adopts Miner's linear damage accumulation theory. In actual operation, bearings and gears will produce a certain amount of fatigue damage in each cycle of each torque, which will be accumulated linearly. Combined with the material fatigue SN curve, when the linear accumulation of damage reaches 1, fatigue failure occurs.

[0107] Right now

[0108] Where n i Indicates that the specimen is subjected to torque T i Number of working cycles under the action of i Indicates the relative stress T of the material on the SN curve in Figure 4 i The number of destruction cycles.

[0109] ② Damage calculation formula: Material damage calculation:

[0110] D i Represents the torque T i Lower meridian N i The damage is related to the number of cycles; e represents the slope of the bearing material fatigue SN curve.

[0111] Calculation of total material damage:

[0112] ③Relationship between damage and input torque, input speed, and running time:

[0113] Calculation of damage equivalence principle under different torques:

[0114] Relationship between speed, torque, running time and damage:

[0115] Where V i To sustain damage D i , at torque T i Input speed under t iTo sustain damage D i At speed V i The following running time.

[0116] According to Miner linear damage, the operating time of the shaft system, gear and other parts systems under the above working conditions is calculated respectively, and then the reliability operating time T of the electric drive transmission is determined (it is recommended to be higher than the national standard recommended time, T≥400). The test operation cycle is:

[0117] As shown in FIG6 , the detailed steps of the technical solution for the reliability testing method of a P13 configuration electric drive transmission motor system described in this application are as follows:

[0118] Test Preparation 14: Secure the assembled P13 configuration electric drive transmission 12 to the test bench. Connect the output of the electric drive transmission to the No. 1 test bench load motor 8 and the No. 2 test bench load motor 7 using axles 10 and 9, respectively, ensuring that the load motors are aligned with the axle holes. Use high-voltage wires to connect the battery simulator 6 and motor controller PEU5 to the P1 and P2 motors. Debug the communication between the test bench 11 and the motor controller PEU5. Use product-level piping to connect and debug cooling equipment such as water and oil temperatures. Add an appropriate amount of lubricant to the electric drive transmission 12, and debug the test bench to ensure normal operation of the electric drive transmission.

[0119] Test entry inspection 15: Conduct a pre-test entry inspection in accordance with the electric drive transmission motor reliability entry inspection rules, which should mainly include product status confirmation, test version data inspection, test control boundary condition confirmation, test bench on-site safety inspection, etc.

[0120] Test Bench Control 16: During the test, control the lubricant and coolant temperatures within the product requirements. Set the oil pump speed based on the product's lubrication flow requirements. Complete the alarm limit settings for the relevant parameters. Set the test bench's drive motor 13 to Speed / Torque mode. Set the test bench's load motors 1 and 2 to Speed / Torque mode. The speeds of the load motors 1 and 2 should be set based on the target speed of the P3 motor, converted to the transmission shaft ratio.

[0121] Zero position learning 16: After the bench, test prototype and software confirmation and debugging are completed, complete the zero position learning of P1 and P3 motors according to product function requirements.

[0122] Initial Performance Test 17: Before the initial performance test, the test prototype is run through a test run. Once normal operation is achieved, the motor's external characteristics are tested. The external characteristics test speed should be measured at 500 rpm intervals up to the maximum operating speed. Speed ​​points should include the rated speed and the turning speed. The external characteristics torque should be measured according to the design torque of the P1 and P3 motors at each speed. The P1 motor is tested only for the power-feed torque portion, while the P3 motor is tested for both the drive and power-feed torque states. The performance test process must ensure that boundary conditions such as lubricant, coolant, lubrication flow rate, and voltage platform are within the specified range. The test process can be performed manually or by programming a test program that associates the boundary values ​​of relevant parameters for measurement.

[0123] The specific implementation steps of the reliability working condition of the motor system are as follows:

[0124] Preparation of reliability operating condition program: Set the test bench motor speed / torque control mode, set the target operating speed, target operating torque, transition time, and operating time of each motor according to the adjusted Table 1 (i.e., the dual-motor system reliability verification operating condition test table), and associate the boundaries of relevant parameters in the operating condition program as the operating condition judgment conditions.

[0125] During the test, the test bench was inspected every 20 hours to ensure there was no leakage of oil, coolant, or other liquids. The high and low voltage lines and their connections were checked for corrosion or exposure. The bench layout and the looseness of the reinforcement bolts were also checked.

[0126] INCA is used to configure the controller's corresponding DBC file and collect all controller DBC parameters. Important parameters, in addition to setting alarm limits on the test bench, require manual verification of key parameters every hour. Important parameters are recorded at a frequency of at least 50 Hz. Full operational data is recorded.

[0127] Conduct a prototype external characteristic test every 40 hours according to the initial performance test procedure. Compare the performance test data during the process and pay attention to the degradation trend.

[0128] Before the test, the vehicle was operated at the designed rated voltage for 80% of the operating time. 18 For 80%-90% of the operating time, the vehicle was operated at the designed minimum operating voltage, with the corresponding speed and torque verified according to the designed values ​​at the minimum operating voltage. 19 For 90%-100% of the operating time, the vehicle was operated at the designed maximum operating voltage, with the corresponding speed and torque verified according to the designed values ​​at the maximum operating voltage. 19 After the cyclic operating conditions were completed, the vehicle was operated for two hours at the rated operating voltage, maximum operating speed, and rated power.

[0129] Performance retest 20: After the reliability test conditions are completed, the performance of the P13 configuration electric drive transmission is retested, and the test content is carried out in accordance with the performance initial test content.

[0130] Post-test analysis 21: Issue a test report for the electric drive transmission test bench and analytical evaluation.

[0131] The above embodiments are preferred implementation methods of the present application, but the implementation methods of the present application are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present application should be considered equivalent replacement methods and are included in the scope of protection of the present application.

Claims

1. A design method for reliability verification of a dual-motor system of a P13 configuration electric drive transmission, characterized in that: The P13 configuration electric drive transmission includes a dual motor system and other parts systems, wherein the other parts systems include gears, shaft systems and bearings, and the design method includes: Based on the structural principle and usage of the P13 configuration electric drive transmission, combined with the motor verification coverage scenario and vehicle road scenario, a dual-motor system reliability verification condition is designed with the P3 motor condition as the main line and the P1 motor condition as the auxiliary condition; Combine product performance design parameters and vehicle control logic to form an initial operating condition test table for reliability verification of the dual-motor system; The operating time of each operating condition in the initial operating condition test table is adjusted to obtain the final required dual-motor system reliability verification operating condition test table and the number of operating condition cycles for the dual-motor system reliability verification.

2. The design method for reliability verification working condition of dual motor system of P13 configuration electric drive transmission according to claim 1 is characterized in that: The steps of adjusting the operating time of each operating condition in the initial operating condition test table to obtain the final required dual-motor system reliability verification operating condition test table and the operating condition cycle number of the dual-motor system reliability verification include: The P13 configuration electric drive transmission is tested based on its design mileage and initial verification operating condition test table. The miner linear damage accumulation theory, vehicle design mileage, the number of alternating load cycles of the P13 configuration electric drive transmission and the P13 configuration electric drive transmission's capacity to change speed and torque rates are used to adjust the operating time of each operating condition in the initial operating condition test table until the other parts and systems of the P13 configuration electric drive transmission meet the reliability strength requirements of the vehicle's design mileage and other parts and systems meet the normal load-bearing level, and the final required dual-motor system reliability verification operating condition test table and the number of operating condition cycles for dual-motor system reliability verification are obtained.

3. The design method for reliability verification working condition of dual motor system of P13 configuration electric drive transmission according to claim 1 is characterized in that: The initial operating condition test table includes a first type of operating condition related to product design performance parameters and a second type of operating condition related to the normal use of the vehicle. The parameters in the first type of operating condition and the second type of operating condition include: P1 motor torque, P3 motor torque, P1 motor speed, P3 motor speed, duration and cumulative time; the cumulative time refers to the total test duration in a single reliability verification cycle; The step of forming an initial operating condition test table for the reliability verification operating condition of the dual-motor system by combining the product performance design parameters and the vehicle control logic includes: Based on the product performance design parameters of the P13 configuration electric drive transmission, the parameter boundaries of the P1 motor torque, the P3 motor torque, the P1 motor speed, and the P3 motor speed in the first type of working condition are determined; the parameter boundaries of the duration and the cumulative time are determined in combination with the cooling capacity of the P13 configuration electric drive transmission, the stator temperature, and the load-bearing capacity of other parts systems; Based on the vehicle control logic, determining the parameter boundaries of the P1 motor torque, the P3 motor torque, the P1 motor speed, and the P3 motor speed in the second type of working condition; The parameter boundaries of duration and cumulative time are determined based on the overall cooling capacity, stator temperature and load-bearing capacity of other parts systems of the P13 configuration electric drive transmission.

4. The design method for reliability verification working condition of dual motor system of P13 configuration electric drive transmission according to claim 3 is characterized in that: The first type of operating conditions include: P3 motor design target operating conditions; In the target operating condition A of the P3 motor design: the boundary of the P3 motor torque is determined according to the peak torque of the P3 motor, the boundary of the P3 motor speed is determined according to the turning speed of the P3 motor, the P1 motor torque and the P1 motor speed are 0, and the duration is determined according to the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the P3 motor continuously outputs the peak torque.

5. The design method for reliability verification working condition of dual motor system of P13 configuration electric drive transmission according to claim 3 is characterized in that: The first type of working condition also includes: motor system coupling working condition B; the motor system coupling working condition B includes three coupling working conditions; In the first coupling condition B1: the boundary of the P3 motor torque is determined according to the rated torque of the P3 motor, the boundary of the P3 motor speed is determined according to the rated speed of the P3 motor, the boundary of the P1 motor torque is determined according to the peak power generation torque of the P1 motor, and the boundary of the P1 motor speed is determined according to the turning speed of the P1 motor; the duration is determined according to the time required for the stator temperature of the P1 motor to rise to the upper limit temperature when the P1 motor outputs the peak power generation torque; In the second coupling condition B2: the limit of the P3 motor torque is determined according to the rated torque of the P3 motor, the limit of the P3 motor speed is determined according to the rated speed of the P3 motor, the limit of the P1 motor torque is determined according to the rated torque of the P1 motor, the limit of the P1 motor speed is determined according to the rated speed of the P1 motor, and the duration is determined according to the cooling capacity of the electric drive transmission. In the third coupling condition B3: the boundary of the P3 motor torque is determined according to the continuous torque at the highest operating speed of the P3 motor, the boundary of the P3 motor speed is determined according to the maximum operating speed of the P3 motor, the boundary of the P1 motor torque is determined according to the continuous torque at the highest operating speed of the P1 motor, the boundary of the P1 motor speed is determined according to the maximum operating speed of the P1 motor, and the duration is pre-set.

6. The design method for reliability verification working condition of dual motor system of P13 configuration electric drive transmission according to claim 3 is characterized in that: The second type of working conditions include: common vehicle working conditions C, In the common vehicle operating condition C: the boundary of the P3 motor torque is determined according to the P3 motor rated torque * preset value, the P3 motor speed is determined according to the preset motor speed, the boundary of the P1 motor torque is determined according to the normal power generation torque of the P1 motor, the boundary of the P1 motor speed is determined according to the normal power generation speed of the P1 motor, and the duration is pre-set.

7. The design method for reliability verification working condition of dual motor system of P13 configuration electric drive transmission according to claim 3 is characterized in that: The first type of working conditions also includes: P3 motor feeding design target working condition D, P3 motor feeding design target working condition D includes three feeding design target working conditions; The P1 motor torque, P1 motor speed and P1 motor duration in the three feeding design target conditions are 0; In the first power feeding design target working condition D1: the boundary value of the P3 motor torque is determined according to the power feeding rated torque of the P3 motor, the boundary value of the P3 motor speed is determined according to the rated speed of the P3 motor, and the duration is determined according to the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the power feeding rated torque is output; In the second power feeding design target working condition D2: the boundary value of the P3 motor torque is determined according to the P3 motor power feeding peak torque, the boundary value of the P3 motor speed is determined according to the P3 motor turning speed, and the duration is determined according to the time required for the stator temperature of the P3 motor to rise to the upper limit temperature when the peak torque is fed; In the third power feeding design target condition D3: the boundary value of the P3 motor torque is determined according to the P3 motor power feeding rated torque, the boundary value of the P3 motor speed is determined according to the P3 motor rated speed, and the duration is determined according to the cooling capacity of the electric drive transmission.

8. The design method for reliability verification working condition of dual motor system of P13 configuration electric drive transmission according to claim 3 is characterized in that: The first type of operating conditions also includes: P1 motor design target operating condition E; In the design target operating condition E of the P1 motor: the P3 motor torque, P3 motor speed and P3 motor duration are 0, the boundary of the P1 motor torque is determined according to the rated torque of the P1 motor, the boundary of the P1 motor speed is determined according to the rated speed of the P1 motor, and the duration is pre-set.

9. A reliability test method for a dual-motor system of a P13 configuration electric drive transmission, characterized in that: include: Test preparation: according to the state of the whole vehicle, install the P13 configuration electric drive transmission on the test bench; Test access inspection: including product status confirmation, test version data inspection, test control boundary condition confirmation, and test bench on-site safety inspection; Bench debugging control and motor zero position learning: Initial performance test: Before the reliability test of the dual-motor system, the P1 motor and the P3 motor of the P13 configuration electric drive transmission are subjected to an external characteristic speed test and an external characteristic torque test; Working condition operation: the working condition is obtained by using the design method of the reliability verification working condition of the dual-motor system of the P13 configuration electric drive transmission according to any one of claims 1 to 8, and the dual-motor system of the P13 configuration electric drive transmission is subjected to cyclic working condition operation according to the obtained working condition cycle number and the dual-motor system reliability verification working condition test table; wherein, in the cyclic working condition operation, the first 80% of the cyclic working conditions are operated according to the designed rated voltage platform, 80%-90% of the cyclic working conditions are operated according to the designed minimum working voltage platform, and 90%-100% of the cyclic working conditions are operated according to the designed maximum working voltage platform; Performance retest: After the dual-motor system reliability test, the P1 motor and the P3 motor of the P13 configuration electric drive transmission are subjected to an external characteristic speed test and an external characteristic torque test; Post-test analysis.

10. The reliability testing method of the dual-motor system of the P13 configuration electric drive transmission according to claim 9 is characterized in that: In the test preparation step, the P13 configuration electric drive transmission is installed on the test bench according to the following process: Use the No. 3 bench drive motor to simulate the vehicle engine to provide energy input for the P13 configuration electric drive transmission. Use the No. 1 bench load motor and the No. 2 bench load motor to simulate the wheel-end load of the P13 configuration electric drive transmission. Use the motor controller PEU to control the functional operation of the P1 motor and P3 motor of the P13 configuration electric drive transmission. Connect the No. 1 bench load motor, the No. 2 bench load motor, the motor controller PEU and the battery simulator to the test bench respectively, and connect the battery simulator to the motor controller PEU.

11. The reliability testing method of the dual-motor system of the P13 configuration electric drive transmission according to claim 9 is characterized in that: During the reliability test of the dual-motor system, the clutch of the P13 configuration electric drive transmission is not engaged throughout the entire process.

12. The reliability testing method of the dual-motor system of the P13 configuration electric drive transmission according to claim 9, characterized in that: In the performance initial test and performance retest steps, When the external characteristic torque test is performed on the P1 motor, only the feeding torque part of the P1 motor is performed. When the external characteristic torque test is performed on the P3 motor, only the driving torque and feeding torque parts of the P3 motor are performed. When the external characteristic speed test is performed on the P1 motor and the P3 motor, it is performed according to the predetermined speed, up to the maximum operating speed of the corresponding motor. The speed points when the external characteristic speed test is performed on the P1 motor and the P3 motor include the rated speed and the turning speed of the corresponding motor; During the initial performance test and re-performance test, it is necessary to ensure that the boundary conditions of the test bench's lubricating oil, coolant, lubrication flow, and voltage platform are within the specified product range of the P13 configuration electric drive transmission.

13. The reliability testing method of the dual-motor system of the P13 configuration electric drive transmission according to claim 9 is characterized in that: In the test bench debugging control steps, it is necessary to first set the coolant temperature and lubricating oil temperature of the test bench according to the lubrication and cooling requirements of the P13 configuration electric drive transmission, and set the oil pump speed of the test bench according to the lubrication flow requirements of the P13 configuration electric drive transmission; after completing the alarm limit setting of the coolant temperature, lubricating oil temperature and oil pump speed, set the No. 1 test bench load motor, No. 2 test bench load motor and No. 3 test bench drive motor to adopt the speed / torque mode, and the speed of the No. 1 test bench load motor and the No. 2 test bench load motor is set according to the speed of the P3 motor and converted according to the shaft speed ratio of the P13 configuration electric drive transmission.

14. The reliability testing method of the dual-motor system of the P13 configuration electric drive transmission according to claim 9, characterized in that: In the operating condition step, after completing 100% of the cycle operating condition operation, the P1 motor and P3 motor of the P13 configuration electric drive transmission are controlled to operate for a preset time at their respective rated operating voltage, maximum operating speed, and rated power.

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