Vehicle model and construction method for DCT vehicle dynamic performance simulation

Abstract

The present invention provides a whole vehicle model and construction method for simulating the dynamic performance of a DCT vehicle model. The whole vehicle model includes: an engine real-time torque module, which sends the engine real-time torque to a dual-mass flywheel module; a dual-mass flywheel module, which simulates the dual-mass flywheel torsional characteristics of the engine real-time torque to obtain a first torque; a dual-clutch automatic transmission module, which determines a third torque according to gear data, a master-slave disc speed difference, and a clutch pressure corresponding to the first torque; a transmission shaft module, which simulates the transmission shaft torsional characteristics and spline clearance of the third torque to obtain a fourth torque; a wheel module, which obtains a wheel longitudinal force based on the fourth torque; and a body module, which determines acceleration according to the wheel longitudinal force, and integrates the acceleration to obtain a vehicle speed. The whole vehicle model provided by the present invention can be used to dynamically analyze the dynamic performance of the whole vehicle during its driving process.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle simulation, and in particular to a whole vehicle model and a construction method for simulating the dynamic performance of a DCT vehicle model. Background Art

[0002] At present, most vehicle models used for vehicle dynamic performance simulation are steady-state simulation models, that is, the gearbox is in a fixed gear position, and the clutch device is in an engaged or disengaged state. The steady-state simulation model is simple and effective, and can meet the needs of most vehicle dynamic performance simulation tests; but the disadvantages are also obvious. In the steady-state simulation model, it is assumed that the automatic transmission of the vehicle model is in a fixed gear position, the engagement and disengagement of the clutch and brake can be completed instantly, and it is assumed that the speed state of the vehicle does not change during the gear shifting process. Obviously, the steady-state simulation model does not match the actual operating conditions of the vehicle, and the steady-state simulation model cannot dynamically analyze the gear shifting process of the vehicle. Summary of the invention

[0003] The main purpose of the present invention is to provide a whole vehicle model and construction method for DCT vehicle power performance simulation, aiming to solve the technical problem that the steady-state simulation model in the prior art cannot dynamically analyze the shifting process of the whole vehicle.

[0004] In a first aspect, the present invention provides a whole vehicle model for simulating the power performance of a DCT vehicle model, wherein the whole vehicle model for simulating the power performance of a DCT vehicle model comprises:

[0005] An engine real-time torque module, used for sending the engine real-time torque to the dual-mass flywheel module;

[0006] A dual-mass flywheel module is used to receive the engine real-time torque sent by the engine real-time torque module, simulate the dual-mass flywheel torsion characteristics of the engine real-time torque, obtain a first torque, and send the first torque to the dual-clutch automatic transmission module;

[0007] A dual-clutch automatic transmission module is used to receive gear data, a speed difference between a master and slave disk, and a clutch pressure corresponding to a first torque, determine a dynamic friction coefficient according to the speed difference between the master and slave disks, obtain torques that can be transmitted by the two clutches and corresponding transmission ratios according to the gear data, the speed difference between the master and slave disks, the clutch pressure, the dynamic friction coefficient, and the static friction coefficient, and combine a clutch transmission torque formula, calculate the product of the torque that can be transmitted by each clutch and the corresponding transmission ratio, and use the sum of the two products as a second torque, multiply the second torque by the transmission efficiency to obtain a third torque, and send the third torque to a transmission shaft module;

[0008] a transmission shaft module, configured to receive a third torque sent by the dual-clutch automatic transmission module, simulate the transmission shaft torsional characteristics and the spline clearance of the third torque to obtain a fourth torque, and send the fourth torque to the wheel module;

[0009] a wheel module, configured to receive the fourth torque sent by the transmission shaft module, obtain a wheel longitudinal force based on the fourth torque, and send the wheel longitudinal force to the body module;

[0010] The body module is used to receive the wheel longitudinal force sent by the wheel module, determine the acceleration according to the wheel longitudinal force, and integrate the acceleration to obtain the vehicle speed.

[0011] Optionally, the engine real-time torque module is specifically used for:

[0012] Receive vehicle speed, accelerator pedal opening, transmission gear position and engine speed;

[0013] Find the corresponding first sub-torque from the accelerator pedal map table based on the vehicle speed, accelerator pedal opening, transmission gear position and engine speed;

[0014] Selecting a minimum value from the first sub-torque, the second sub-torque and the third sub-torque as the fourth sub-torque, wherein the second sub-torque is determined based on the external characteristics of the engine, and the third sub-torque is the maximum torque corresponding to the current working condition of the engine;

[0015] Processing the fourth sub-torque by a preset torque filtering method to obtain a processed torque, and selecting a minimum value from the zero-crossing torque holding value and the processed torque as the fifth sub-torque;

[0016] The maximum value is selected from the torque corresponding to when the brake pedal is released and the accelerator pedal is not stepped on and the minimum torque corresponding to the current working condition of the engine as the creep torque;

[0017] According to the creep torque and the fifth sub-torque, a sixth sub-torque is obtained;

[0018] determining a seventh sub-torque based on an engine torque response characteristic;

[0019] Selecting a minimum value from the sixth sub-torque and the seventh sub-torque as the engine real-time torque;

[0020] Sends the engine real-time torque to the torque converter module.

[0021] Optionally, the body module is specifically used for:

[0022] Receiving the vehicle motion influencing factor sent by the test data input module and receiving the wheel longitudinal force sent by the wheel module;

[0023] The acceleration is determined based on the vehicle motion influencing factors and the wheel longitudinal force.

[0024] Optionally, the vehicle motion influencing factors include:

[0025] Vehicle weight, wind speed, road slope and tire slip rate.

[0026] Optionally, the whole vehicle model for simulating the power performance of a DCT vehicle model further includes:

[0027] The test data input module is used to send vehicle speed, transmission gear and engine speed to the engine real-time torque module, and send vehicle weight, wind speed, road slope and tire slip rate to the body module.

[0028] Optionally, the whole vehicle model for simulating the power performance of a DCT vehicle model further includes:

[0029] The simulation output detection module is used to compare and analyze the simulation results with the actual vehicle test results.

[0030] In a second aspect, the present invention further provides a method for constructing a whole vehicle model for simulating the power performance of a DCT vehicle model, the method for constructing a whole vehicle model for simulating the power performance of a DCT vehicle model comprising:

[0031] Build engine real-time torque module;

[0032] Building a dual-mass flywheel module;

[0033] Building dual-clutch automatic transmission modules;

[0034] Wherein, constructing the dual-clutch automatic transmission module includes a shaft system module modeling step, and the shaft system module modeling step includes:

[0035] Obtaining the transmission route of each gear of the dual-clutch automatic transmission and the meshing relationship of each gear;

[0036] According to each shaft and its components, and with the clutch or synchronization element as the dividing point, the rotational inertia of the dual clutch automatic transmission is divided into multiple parts of rotational inertia;

[0037] Obtain the speed ratio corresponding to each gear transmission route of the dual-clutch automatic transmission, as well as the rotational inertia equivalent to the input shaft of the dual-clutch automatic transmission when each gear is engaged, and calculate the rotational inertia of each divided part according to the equivalent relationship of the rotational inertia of the gear pair;

[0038] Build the shaft system module according to the power transmission path, equivalent position of equivalent rotational inertia, speed ratio and gear selection;

[0039] Mount the moments of inertia of each part at equivalent positions of equivalent moments of inertia;

[0040] Build the drive shaft module;

[0041] Build the wheel module;

[0042] Construct the body module.

[0043] Optionally, the rotational inertia of the dual-clutch automatic transmission is divided into multiple parts according to each shaft and its components, and with the clutch or synchronization element as the dividing point, including:

[0044] The inner input shaft, the parts fixedly connected to the inner input shaft, and the gear meshing with the outer gear fixed to the inner input shaft are regarded as a whole, and the moment of inertia of the whole is taken as an equivalent factor of the moment of inertia of the dual clutch automatic transmission;

[0045] The external input shaft, the parts fixedly connected to the external input shaft, and the gear meshing with the gear fixedly connected to the external input shaft are regarded as a whole, and the rotational inertia of the whole is taken as an equivalent factor of the rotational inertia of the dual-clutch automatic transmission;

[0046] The first output shaft, the parts fixedly connected to the first output shaft, and the gear meshing with the gear fixedly connected to the first output shaft are regarded as a whole, and the moment of inertia of the whole is taken as an equivalent factor of the moment of inertia of the dual-clutch automatic transmission;

[0047] The second output shaft, the parts fixedly connected to the second output shaft, and the gear meshing with the gear fixed to the second output shaft are regarded as a whole, and the rotational inertia of the whole is used as an equivalent factor of the rotational inertia of the dual-clutch automatic transmission.

[0048] Optionally, the obtaining of the speed ratio corresponding to each gear transmission route of the dual-clutch automatic transmission and the moment of inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear, and the calculation of the moment of inertia of each divided part according to the equivalent relationship of the moment of inertia of the gear pair, includes:

[0049] Obtain the speed ratio of each gear and the final reduction ratio of the dual-clutch automatic transmission, as well as the moment of inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear;

[0050] The moment of inertia of the dual clutch automatic transmission equivalent to the input shaft when it is engaged in each gear is expressed by using the moment of inertia of each part as an equivalent factor;

[0051] Based on the magnitude of the rotational inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear, the magnitude of the rotational inertia of each part serving as an equivalent factor is calculated.

[0052] Optionally, constructing a dual-clutch automatic transmission module further includes a dual-clutch module modeling step, and the dual-clutch module modeling step includes:

[0053] Determine the dynamic friction coefficient of the clutch according to the obtained clutch pressure P and the speed difference between the driving and driven discs;

[0054] Get the inner diameter R of the friction surface of the clutch 内 , Friction surface outer diameter R 外 and the number of friction surfaces N;

[0055] Take the smaller value of the dynamic friction coefficient and the static friction coefficient as μ, and according to the clutch torque formula Build the dual clutch module.

[0056] In the present invention, the whole vehicle model for simulating the power performance of a DCT vehicle model includes: an engine real-time torque module, which is used to send the engine real-time torque to a dual-mass flywheel module; a dual-mass flywheel module, which is used to receive the engine real-time torque sent by the engine real-time torque module, simulate the dual-mass flywheel torsional characteristics of the engine real-time torque, obtain a first torque, and send the first torque to a dual-clutch automatic transmission module; a dual-clutch automatic transmission module, which is used to receive gear data, a master-slave disc speed difference, and a clutch pressure corresponding to the first torque, determine the dynamic friction coefficient according to the master-slave disc speed difference, and obtain the torque that can be transmitted by the two clutches respectively and the static friction coefficient according to the gear data, the master-slave disc speed difference, the clutch pressure, the dynamic friction coefficient, and the static friction coefficient in combination with the clutch transmission torque formula. Corresponding transmission ratio, calculate the product of the torque that can be transmitted by each clutch and the corresponding transmission ratio, and take the sum of the two products as the second torque, multiply the second torque by the transmission efficiency, obtain the third torque, and send the third torque to the transmission shaft module; the transmission shaft module is used to receive the third torque sent by the dual-clutch automatic transmission module, simulate the transmission shaft torsional characteristics and spline clearance of the third torque, obtain the fourth torque, and send the fourth torque to the wheel module; the wheel module is used to receive the fourth torque sent by the transmission shaft module, and obtain the wheel longitudinal force based on the fourth torque, and send the wheel longitudinal force to the body module; the body module is used to receive the wheel longitudinal force sent by the wheel module, and determine the acceleration according to the wheel longitudinal force, and integrate the acceleration to obtain the vehicle speed. Through the present invention, the whole vehicle model can be used to dynamically analyze the shifting process of the whole vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a schematic diagram of the architecture of an embodiment of a whole vehicle model for simulating the dynamic performance of a DCT vehicle model according to the present invention;

[0058] Figure 2 It is a flow chart of an embodiment of a method for constructing a vehicle model for simulating the dynamic performance of a DCT vehicle model according to the present invention;

[0059] Figure 3A schematic diagram of a transmission route of a dual-clutch automatic transmission in one embodiment of the present invention;

[0060] Figure 4 It is a schematic diagram of a shaft system module of a dual-clutch automatic transmission in one embodiment of the present invention.

[0061] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0062] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0063] In a first aspect, an embodiment of the present invention provides a vehicle model for simulating the dynamic performance of a DCT vehicle. Figure 1 , Figure 1 FIG. 1 is a schematic diagram of the structure of an embodiment of a vehicle model for simulating the dynamic performance of a DCT vehicle according to the present invention. Figure 1 As shown in the figure, the vehicle model used for DCT vehicle power performance simulation includes:

[0064] An engine real-time torque module 10, for sending the engine real-time torque to a dual-mass flywheel module 20;

[0065] In this embodiment, during the simulation process, the engine real-time torque module 10 calculates the engine real-time torque through the vehicle operating condition, and sends the engine real-time torque to the dual-mass flywheel module 20 .

[0066] Further, in one embodiment, the engine real-time torque module 10 is specifically used for:

[0067] Receive vehicle speed, accelerator pedal opening, transmission gear position and engine speed; search for the corresponding first sub-torque from the accelerator pedal map table based on the vehicle speed, accelerator pedal opening, transmission gear position and engine speed; select the minimum value from the first sub-torque, the second sub-torque and the third sub-torque as the fourth sub-torque, wherein the second sub-torque is determined based on the external characteristics of the engine, and the third sub-torque is the maximum torque corresponding to the current working condition of the engine; process the fourth sub-torque by a preset torque filtering method to obtain a processed torque, and select the minimum value from the zero-crossing torque holding value and the processed torque as the fifth sub-torque; select the maximum value from the torque corresponding to when the brake pedal is released and the accelerator pedal is not stepped on and the minimum torque corresponding to the current working condition of the engine as the creep torque; obtain the sixth sub-torque based on the creep torque and the fifth sub-torque; determine the seventh sub-torque based on the engine torque response characteristics; select the minimum value from the sixth sub-torque and the seventh sub-torque as the engine real-time torque; send the engine real-time torque to the torque converter module.

[0068] In this embodiment, the accelerator pedal opening is set by the working condition data, and the vehicle speed, gearbox gear and engine speed are fed back by the back-end module; based on the vehicle speed, accelerator pedal opening, gearbox gear and engine speed, the corresponding first sub-torque is searched from the accelerator pedal map table. The accelerator pedal map table records the corresponding relationship between the vehicle speed, accelerator pedal opening, gearbox gear and engine speed and torque.

[0069] The second sub-torque can be determined based on the external characteristics of the engine, and the maximum torque allowed by the current operating condition can be determined based on the current operating condition of the engine, which is recorded as the third sub-torque. Here, the first sub-torque is limited based on the second sub-torque and the third sub-torque, that is, the first sub-torque is limited based on the engine characteristics. Specifically, the minimum value is selected from the first sub-torque, the second sub-torque and the third sub-torque as the fourth sub-torque.

[0070] In this embodiment, considering that the driver may drive aggressively, in order to improve driving safety, it is necessary to perform torque filtering and limiting on the fourth sub-torque to obtain the fifth sub-torque. Specifically, the fourth sub-torque is processed by a preset torque filtering method to obtain a processed torque. Then, the minimum value is selected from the zero-crossing torque holding value and the processed torque as the fifth sub-torque. Among them, the zero-crossing torque holding value is a preset value.

[0071] Furthermore, in one embodiment, the preset torque filtering method is:

[0072] Torque low-pass filter, torque rate limit filter.

[0073] In this embodiment, the calculation formula corresponding to the torque low-pass filter is:

[0074]

[0075] Where y is the output torque after torque low-pass filtering, t is the calculation step set by the control software, usually 0.01, T is the calibration amount (determined according to the accelerator pedal opening and vehicle speed), u is the current torque demand, and y0 is the fourth sub-torque.

[0076] The calculation formula corresponding to the torque rate limit filter (Ratelimit) is:

[0077] y=min[(u-y0),Lu]+y0 or y=max[(u-y0),Ld]+y0

[0078] Wherein y is the output torque after torque rate limit filtering, u is the current torque demand, Lu is the calibration amount of the demand torque increase, Ld is the calibration amount of the demand torque increase, and y0 is the fourth sub-torque.

[0079] The torque corresponding to when the brake pedal is released and the accelerator pedal is not stepped on, that is, the torque determined by the automatic transmission adjustment system when the accelerator pedal and the brake pedal are both at zero opening; or the torque determined by the automatic transmission adjustment system when the brake pedal opening is zero and the accelerator pedal opening is less than the preset opening. This torque is compared with the minimum torque corresponding to the current working condition of the engine, and the maximum value of the two is taken as the creep torque.

[0080] The creep torque may be superimposed on the fifth sub-torque to obtain the sixth sub-torque; or the creep torque may be compared with the fifth sub-torque to take the larger one as the sixth sub-torque.

[0081] The engine torque response characteristics are determined through bench tests. The engine torque response characteristics calibrate the corresponding relationship between the accelerator pedal opening and the holding time corresponding to the accelerator pedal opening and the torque. Based on this, the seventh sub-torque can be determined according to the accelerator pedal opening and the holding time corresponding to the accelerator pedal opening.

[0082] After the sixth sub-torque and the seventh sub-torque are determined, a minimum value is selected from the sixth sub-torque and the seventh sub-torque as the engine real-time torque.

[0083] The dual-mass flywheel module 20 is used to receive the engine real-time torque sent by the engine real-time torque module 10, simulate the dual-mass flywheel torsion characteristics of the engine real-time torque, obtain the first torque, and send the first torque to the dual-clutch automatic transmission module 30;

[0084] In this embodiment, the dual mass flywheel module 20 simulates the dual mass flywheel torsion characteristic of the engine real-time torque based on a preset function to obtain a first torque. The input of the function is the engine real-time torque, and the output is the first torque. The function is constructed based on the dual mass flywheel torsion characteristic.

[0085] The dual-clutch automatic transmission module 30 is used to receive the gear data, the speed difference between the master and slave discs, and the clutch pressure corresponding to the first torque, determine the dynamic friction coefficient according to the speed difference between the master and slave discs, obtain the torques that can be transmitted by the two clutches and the corresponding transmission ratios according to the gear data, the speed difference between the master and slave discs, the clutch pressure, the dynamic friction coefficient and the static friction coefficient, and the clutch transmission torque formula, calculate the product of the torque that can be transmitted by each clutch and the corresponding transmission ratio, and use the sum of the two products as the second torque, multiply the second torque by the transmission efficiency to obtain the third torque, and send the third torque to the transmission shaft module;

[0086] In this embodiment, the transmission efficiency is related to environmental factors, and the corresponding transmission efficiency can be determined according to current environmental factors (such as temperature).

[0087] The transmission shaft module 40 is used to receive the third torque sent by the dual-clutch automatic transmission module 30, simulate the transmission shaft torsional characteristics and the spline clearance of the third torque to obtain a fourth torque, and send the fourth torque to the wheel module;

[0088] The wheel module 50 is used to receive the fourth torque sent by the transmission shaft module 40, obtain the wheel longitudinal force based on the fourth torque, and send the wheel longitudinal force to the body module;

[0089] In this embodiment, the wheel module 50 determines the wheel longitudinal force corresponding to the fourth torque based on the pre-calibrated correspondence between the torque and the wheel longitudinal force, and sends the wheel longitudinal force to the body module 60. The correspondence may be in the form of a function (the function input is the torque, and the output is the wheel longitudinal force) or in the form of a key-value pair (the key is the torque, and the value is the wheel longitudinal force).

[0090] The body module 60 is used to receive the wheel longitudinal force sent by the wheel module 50, determine the acceleration according to the wheel longitudinal force, and integrate the acceleration to obtain the vehicle speed.

[0091] In this embodiment, the vehicle body module 60 determines the acceleration according to the longitudinal force of the wheel based on the corresponding relationship between the longitudinal force of the wheel and the acceleration, and then integrates the acceleration to obtain the vehicle speed.

[0092] Furthermore, in one embodiment, the body module 60 is specifically used for:

[0093] Receive the vehicle motion influence factor sent by the test data input module and receive the wheel longitudinal force sent by the wheel module; determine the acceleration based on the vehicle motion influence factor and the wheel longitudinal force.

[0094] In this embodiment, the vehicle motion influencing factors include: vehicle weight, wind speed, road slope and tire slip rate. The body module 60 obtains acceleration based on the wheel longitudinal force and comprehensively considers the vehicle weight, wind speed, road slope and tire slip rate. Among them, a related function can be pre-set, and the input of the function is the wheel longitudinal force, vehicle weight, wind speed, road slope and tire slip rate, and the output is acceleration.

[0095] Furthermore, in one embodiment, the vehicle model for simulating the power performance of a DCT vehicle model further includes:

[0096] The test data input module is used to send vehicle speed, transmission gear and engine speed to the engine real-time torque module, and send vehicle weight, wind speed, road slope and tire slip rate to the body module.

[0097] Furthermore, in one embodiment, the vehicle model for simulating the power performance of a DCT vehicle model further includes:

[0098] The simulation output detection module is used to compare and analyze the simulation results with the actual vehicle test results.

[0099] In this embodiment, the engine real-time torque module is used to send the engine real-time torque to the dual-mass flywheel module; the dual-mass flywheel module is used to receive the engine real-time torque sent by the engine real-time torque module, simulate the dual-mass flywheel torsional characteristics of the engine real-time torque, obtain the first torque, and send the first torque to the dual-clutch automatic transmission module; the dual-clutch automatic transmission module is used to receive gear data, the master and slave disc speed difference and the clutch pressure corresponding to the first torque, determine the dynamic friction coefficient according to the master and slave disc speed difference, and obtain the torque that can be transmitted by the two clutches and the corresponding transmission ratio according to the gear data, the master and slave disc speed difference, the clutch pressure, the dynamic friction coefficient and the static friction coefficient in combination with the clutch transmission torque formula, and calculate each The product of the torque that can be transmitted by each clutch and the corresponding transmission ratio is calculated, and the sum of the two products is used as the second torque. The second torque is multiplied by the transmission efficiency to obtain the third torque, and the third torque is sent to the transmission shaft module; the transmission shaft module is used to receive the third torque sent by the dual-clutch automatic transmission module, simulate the transmission shaft torsional characteristics and spline clearance of the third torque, obtain the fourth torque, and send the fourth torque to the wheel module; the wheel module is used to receive the fourth torque sent by the transmission shaft module, and obtain the wheel longitudinal force based on the fourth torque, and send the wheel longitudinal force to the body module; the body module is used to receive the wheel longitudinal force sent by the wheel module, and determine the acceleration according to the wheel longitudinal force, and integrate the acceleration to obtain the vehicle speed. Through this embodiment, the whole vehicle model can be used to dynamically analyze the shifting process of the whole vehicle.

[0100] In a second aspect, an embodiment of the present invention provides a vehicle model construction method for DCT vehicle power performance simulation. Figure 2 , Figure 2 FIG. 1 is a flow chart of an embodiment of a vehicle model construction method for DCT vehicle power performance simulation according to the present invention. Figure 2 As shown in the figure, the vehicle model construction method for DCT vehicle power performance simulation includes:

[0101] Step S10, constructing an engine real-time torque module;

[0102] In this embodiment, the engine real-time torque module is constructed based on a preset calculation program combined with a data interface. The data interface is used to receive the vehicle speed, accelerator pedal opening, gear position and engine speed sent by the test data input module, and the calculation program is used to execute the steps executed by the above engine real-time torque module.

[0103] Step S20, constructing a dual-mass flywheel module;

[0104] In this embodiment, a dual mass flywheel module is constructed based on the torsional characteristics of the dual mass flywheel, so that the dual mass flywheel module can simulate the torsional characteristics of the dual mass flywheel for the real-time torque of the engine.

[0105] Step S30, constructing a dual-clutch automatic transmission module;

[0106] Wherein, constructing the dual-clutch automatic transmission module includes a shaft system module modeling step, and the shaft system module modeling step includes:

[0107] Step S301, obtaining the transmission route of each gear of the dual-clutch automatic transmission and the meshing relationship of each gear;

[0108] It can be understood that the transmission route of each gear of the dual-clutch automatic transmission and the meshing relationship of each gear can be determined based on the transmission specification parameter table and the transmission route schematic diagram.

[0109] Step S302, dividing the rotational inertia of the dual clutch automatic transmission into multiple rotational inertia parts according to each shaft and its components, and taking the clutch or synchronization element as a dividing point;

[0110] Step S303, obtaining the speed ratio corresponding to each gear transmission route of the dual-clutch automatic transmission, and the rotational inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear, and calculating the rotational inertia of each divided part according to the equivalent relationship of the rotational inertia of the gear pair;

[0111] In this embodiment, the dual-clutch automatic transmission is equivalent to simplify the calculation of the moment of inertia. To this end, each shaft and the parts that are usually connected on the shaft (including fixed connections and external gear meshing connections) can be regarded as a whole, and the equivalent inertia can be equivalent with each clutch or synchronization element as a dividing point. The dual-clutch automatic transmission can be divided into multiple parts of equivalent moment of inertia, and the equations are listed and solved in combination with the equivalent moment of inertia of each gear provided in a parameter table of the transmission to obtain the multiple divided parts of equivalent moment of inertia.

[0112] Step S304, building a shaft system module according to the power transmission path, the equivalent position of the equivalent moment of inertia, the speed ratio and the gear selection;

[0113] Step S305, mounting the rotational inertia of each part on an equivalent position of the equivalent rotational inertia;

[0114] Let's take a specific example to illustrate:

[0115] like Figure 3 As shown, Figure 3The transmission routes of each gear and the meshing relationship of each gear of the 6-speed dual-clutch automatic transmission are given in FIG. It can be understood that the embodiment of the present invention does not limit the structure of the dual-clutch automatic transmission, and other types of dual-clutch automatic transmissions can also be processed in the same manner.

[0116] for Figure 3 In the dual-clutch automatic transmission, IS inner, IS outer, OS1, and OS2 represent an inner input shaft, an outer input shaft, a first output shaft, and a second output shaft, respectively.

[0117] The inner input shaft (IS inner) is an even-numbered shaft, corresponding to the 2nd, 4th, and 6th gear pairs, and the outer input shaft (ISouter) is an odd-numbered shaft, corresponding to the 3rd and 5th gear pairs.

[0118] Specific to Figure 2 In the embodiment, each shaft and the parts that are usually connected on the shaft (including fixed connection and external gear meshing connection) are regarded as a whole, and step S302 includes:

[0119] Step S3021, the inner input shaft, the parts fixedly connected to the inner input shaft, and the gear meshing with the outer gear fixed to the inner input shaft are regarded as a whole, and the moment of inertia of the whole is used as an equivalent factor of the moment of inertia of the dual clutch automatic transmission;

[0120] In this embodiment, the inner input shaft, the parts fixedly connected to the inner input shaft, and the gears externally meshed with the gears fixed to the inner input shaft and loosely sleeved on other shafts are regarded as a rotating part equivalent to the inner input shaft through the gear ratio, and the rotational inertia of this part is calculated as J ISinner .

[0121] Step S3022, the external input shaft, the parts fixedly connected to the external input shaft, and the gear meshing with the gear fixedly connected to the external input shaft are regarded as a whole, and the moment of inertia of the whole is used as an equivalent factor of the moment of inertia of the dual-clutch automatic transmission;

[0122] In this embodiment, the external input shaft, the parts fixedly connected to the external input shaft, and the gears externally meshed with the gears fixedly connected to the external input shaft and loosely sleeved on other shafts are regarded as a rotating part equivalent to the external input shaft through the gear ratio, and the rotational inertia of this part is calculated as J ISouter .

[0123] Step S3023, the first output shaft, the components fixedly connected to the first output shaft, and the gear meshing with the gear fixedly connected to the first output shaft are regarded as a whole, and the moment of inertia of the whole is used as an equivalent factor of the moment of inertia of the dual-clutch automatic transmission;

[0124] In this embodiment, the first output shaft, the parts fixedly connected to the first output shaft, and the gears externally meshed with the gear fixed to the first output shaft and loosely sleeved on other shafts are equivalent to the rotating parts on the first output shaft through the gear ratio, and are regarded as a whole. The moment of inertia of this part is calculated as J OS1 .

[0125] Step S3024, the second output shaft, the parts fixedly connected to the second output shaft, and the gear meshing with the gear fixed to the second output shaft are regarded as a whole, and the moment of inertia of the whole is used as an equivalent factor of the moment of inertia of the dual-clutch automatic transmission.

[0126] In this embodiment, the second output shaft, the parts fixedly connected to the second output shaft, and the gears externally meshing with the gear fixed to the second output shaft and loosely sleeved on other shafts are regarded as a rotating part equivalent to the second output shaft through the gear ratio, and the rotational inertia of this part is calculated as J OS2 .

[0127] At this point, the equivalent division of the rotational inertia of the dual-clutch automatic transmission is completed.

[0128] Furthermore, in one embodiment, step S303 includes:

[0129] Step S3031, obtaining the speed ratio of each gear and the final reduction ratio of the dual-clutch automatic transmission, and the moment of inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear;

[0130] In this embodiment, for Figure 3 In the dual-clutch automatic transmission, the speed ratios of the six gears are recorded as: i1, i2, i3, i4, i5, i6; the two main reduction ratios are recorded as i fd1 and i fd2 It can be understood that the above speed ratios and final reduction ratios are known parameters in the dual-clutch automatic transmission.

[0131] Step S3032, the rotational inertia of the input shaft equivalent to the rotational inertia of each part of the dual clutch automatic transmission when the dual clutch automatic transmission is engaged in each gear is expressed by using the rotational inertia of each part as an equivalent factor;

[0132] In this embodiment, the inertia equivalent to the input shaft = output shaft inertia * (speed ratio of the output shaft to the input shaft) 2 The rotational inertia of the dual-clutch automatic transmission equivalent to the input shaft when it is engaged in each gear is expressed by the rotational inertia of each part as an equivalent factor.

[0133] Step S3033, calculating the magnitude of the moment of inertia of each part as an equivalent factor according to the magnitude of the moment of inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear.

[0134] For Figure 2 For the dual-clutch automatic transmission in FIG, the moment of inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear can be expressed as:

[0135]

[0136]

[0137]

[0138]

[0139]

[0140]

[0141] The moments of inertia J1, J2, J3, J4, J5, and J6 of the dual-clutch automatic transmission in each gear equivalent to the input shaft in the above formula can be obtained from the specification parameter table of the dual-clutch automatic transmission, and then substituted into the above equations to solve for J ISouter , J ISinner , J OS1 and J OS2 At this point, the equivalent process of the rotational inertia of the dual-clutch automatic transmission is completed.

[0142] See also Figure 4 As shown, taking a six-speed dual-clutch automatic transmission as an example, after determining the rotational inertia of each part, the shaft system module can be built according to the power transmission path, the equivalent position of the equivalent rotational inertia, the speed ratio and the gear selection, and then the rotational inertia of each part is mounted at the equivalent position of the equivalent rotational inertia. Figure 4 The inertia of the odd-numbered shafts, the inertia of the even-numbered shafts, the inertia of the first output shaft, and the inertia of the second output shaft. At this point, the construction of the shaft system module has been completed. Through the shaft system module, the output torque of the dual-clutch automatic transmission can be determined according to the input engine flywheel torque. In some preferred embodiments, the shaft system efficiency MAP is also taken into account, so a DCT efficiency module is also designed. The DCT efficiency module reflects the transmission efficiency of the DCT under various working conditions such as temperature and speed. It is not a fixed value, and can reflect the transmission efficiency under different working conditions. In terms of model accuracy, it is closer to the actual situation.

[0143] Furthermore, in one embodiment, constructing a dual-clutch automatic transmission module further includes a dual-clutch module modeling step, and the dual-clutch module modeling step includes:

[0144] Determine the dynamic friction coefficient of the clutch according to the obtained clutch pressure P and the speed difference between the driving and driven discs;

[0145] Get the inner diameter R of the friction surface of the clutch 内 , Friction surface outer diameter R 外 and the number of friction surfaces N;

[0146] Take the smaller value of the dynamic friction coefficient and the static friction coefficient as μ, and according to the clutch torque formula Build the dual clutch module.

[0147] It should be noted that after determining the smaller value of the dynamic friction coefficient μ and the static friction coefficient, the smaller of the two is substituted into the clutch transfer torque formula for calculation, so that the clutch transfer torque can be determined using the constructed dual clutch module.

[0148] The shift selection module mainly obtains the shaft system gear change instruction and the gear signal for modeling, which is well known to those skilled in the art and will not be described in detail in the embodiments of the present invention. After that, the dual clutch module, shaft system module and shift selection module are integrated to complete the modeling of the dual clutch automatic transmission.

[0149] Step S40, constructing a transmission shaft module;

[0150] In this embodiment, a transmission shaft module is constructed according to the transmission characteristics, so that the transmission shaft module can be used to simulate the transmission shaft torsional characteristics and spline clearance of the torque sent by the dual-clutch automatic transmission module.

[0151] Step S50, constructing a wheel module;

[0152] Step S60: constructing a vehicle body module.

[0153] In this embodiment, the wheel module and the body module are constructed according to the vehicle motion characteristics, so that the wheel module and the body module can implement the execution actions of the wheel module and the body module described in the above embodiments.

[0154] By combining the above-mentioned modules according to the data processing flow, a whole vehicle model for simulating the dynamic performance of a DCT vehicle can be obtained.

[0155] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or system. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or system including the element.

[0156] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0157] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art can be embodied in the form of a software product, which is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes a number of instructions for a terminal device to execute the methods described in each embodiment of the present invention.

[0158] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A vehicle model for DCT vehicle power performance simulation, characterized in that: The whole vehicle model for DCT vehicle power performance simulation includes: An engine real-time torque module, used for sending the engine real-time torque to the dual-mass flywheel module; A dual-mass flywheel module is used to receive the engine real-time torque sent by the engine real-time torque module, simulate the dual-mass flywheel torsion characteristics of the engine real-time torque, obtain a first torque, and send the first torque to the dual-clutch automatic transmission module; A dual-clutch automatic transmission module is used to receive gear data, a speed difference between a master and slave disk, and a clutch pressure corresponding to a first torque, determine a dynamic friction coefficient according to the speed difference between the master and slave disks, obtain torques that can be transmitted by the two clutches and corresponding transmission ratios according to the gear data, the speed difference between the master and slave disks, the clutch pressure, the dynamic friction coefficient, and the static friction coefficient, and combine a clutch transmission torque formula, calculate the product of the torque that can be transmitted by each clutch and the corresponding transmission ratio, and use the sum of the two products as a second torque, multiply the second torque by the transmission efficiency to obtain a third torque, and send the third torque to a transmission shaft module; a transmission shaft module, configured to receive a third torque sent by the dual-clutch automatic transmission module, simulate the transmission shaft torsional characteristics and the spline clearance of the third torque to obtain a fourth torque, and send the fourth torque to the wheel module; a wheel module, configured to receive the fourth torque sent by the transmission shaft module, obtain a wheel longitudinal force based on the fourth torque, and send the wheel longitudinal force to the body module; The body module is used to receive the wheel longitudinal force sent by the wheel module, determine the acceleration according to the wheel longitudinal force, and integrate the acceleration to obtain the vehicle speed.

2. The vehicle model for simulating the dynamic performance of a DCT vehicle according to claim 1, characterized in that: The engine real-time torque module is specifically used for: Receive vehicle speed, accelerator pedal opening, transmission gear position and engine speed; Find the corresponding first sub-torque from the accelerator pedal map table based on the vehicle speed, accelerator pedal opening, transmission gear position and engine speed; Selecting a minimum value from the first sub-torque, the second sub-torque and the third sub-torque as the fourth sub-torque, wherein the second sub-torque is determined based on the external characteristics of the engine, and the third sub-torque is the maximum torque corresponding to the current working condition of the engine; Processing the fourth sub-torque by a preset torque filtering method to obtain a processed torque, and selecting a minimum value from the zero-crossing torque holding value and the processed torque as the fifth sub-torque; The maximum value is selected from the torque corresponding to when the brake pedal is released and the accelerator pedal is not stepped on and the minimum torque corresponding to the current working condition of the engine as the creep torque; According to the creep torque and the fifth sub-torque, a sixth sub-torque is obtained; determining a seventh sub-torque based on an engine torque response characteristic; Selecting a minimum value from the sixth sub-torque and the seventh sub-torque as the engine real-time torque; Sends the engine real-time torque to the torque converter module.

3. The vehicle model for DCT vehicle power performance simulation according to claim 2, characterized in that: The body module is specifically used for: Receiving the vehicle motion influencing factor sent by the test data input module and receiving the wheel longitudinal force sent by the wheel module; The acceleration is determined based on the vehicle motion influencing factors and the wheel longitudinal force.

4. The vehicle model for DCT vehicle power performance simulation as claimed in claim 3, characterized in that: The vehicle motion influencing factors include: Vehicle weight, wind speed, road slope and tire slip rate.

5. The vehicle model for DCT vehicle power performance simulation according to claim 4, characterized in that: The whole vehicle model for DCT vehicle power performance simulation also includes: The test data input module is used to send vehicle speed, transmission gear and engine speed to the engine real-time torque module, and send vehicle weight, wind speed, road slope and tire slip rate to the body module.

6. The vehicle model for DCT vehicle power performance simulation according to claim 5, characterized in that: The whole vehicle model for DCT vehicle power performance simulation also includes: The simulation output detection module is used to compare and analyze the simulation results with the actual vehicle test results.

7. A method for constructing a vehicle model for DCT vehicle power performance simulation according to any one of claims 1 to 6, characterized in that: The construction method comprises: Build engine real-time torque module; Building a dual-mass flywheel module; Building dual-clutch automatic transmission modules; Wherein, constructing the dual-clutch automatic transmission module includes a shaft system module modeling step, and the shaft system module modeling step includes: Obtaining the transmission route of each gear of the dual-clutch automatic transmission and the meshing relationship of each gear; According to each shaft and its components, and with the clutch or synchronization element as the dividing point, the rotational inertia of the dual clutch automatic transmission is divided into multiple parts of rotational inertia; Obtain the speed ratio corresponding to each gear transmission route of the dual-clutch automatic transmission, as well as the rotational inertia equivalent to the input shaft of the dual-clutch automatic transmission when each gear is engaged, and calculate the rotational inertia of each divided part according to the equivalent relationship of the rotational inertia of the gear pair; Build the shaft system module according to the power transmission path, equivalent position of equivalent rotational inertia, speed ratio and gear selection; Mount the moments of inertia of each part at equivalent positions of equivalent moments of inertia; Build the drive shaft module; Build the wheel module; Construct the body module.

8. The construction method according to claim 7, characterized in that: The rotational inertia of the dual clutch automatic transmission is divided into multiple parts according to each shaft and its components, and with the clutch or synchronization element as the dividing point, including: The inner input shaft, the parts fixedly connected to the inner input shaft, and the gear meshing with the outer gear fixed to the inner input shaft are regarded as a whole, and the moment of inertia of the whole is taken as an equivalent factor of the moment of inertia of the dual clutch automatic transmission; The external input shaft, the parts fixedly connected to the external input shaft, and the gear meshing with the gear fixedly connected to the external input shaft are regarded as a whole, and the rotational inertia of the whole is taken as an equivalent factor of the rotational inertia of the dual-clutch automatic transmission; The first output shaft, the parts fixedly connected to the first output shaft, and the gear meshing with the gear fixedly connected to the first output shaft are regarded as a whole, and the moment of inertia of the whole is taken as an equivalent factor of the moment of inertia of the dual-clutch automatic transmission; The second output shaft, the parts fixedly connected to the second output shaft, and the gear meshing with the gear fixed to the second output shaft are regarded as a whole, and the rotational inertia of the whole is used as an equivalent factor of the rotational inertia of the dual-clutch automatic transmission.

9. The construction method according to claim 8, characterized in that: The obtaining of the speed ratio corresponding to each gear transmission route of the dual-clutch automatic transmission and the rotational inertia equivalent to the input shaft of the dual-clutch automatic transmission when the dual-clutch automatic transmission is engaged in each gear, and the calculation of the rotational inertia of each divided part according to the equivalent relationship of the rotational inertia of the gear pair, includes: Obtain the speed ratio of each gear and the final reduction ratio of the dual-clutch automatic transmission, as well as the moment of inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear; The moment of inertia of the dual clutch automatic transmission equivalent to the input shaft when it is engaged in each gear is expressed by using the moment of inertia of each part as an equivalent factor; Based on the magnitude of the rotational inertia equivalent to the input shaft when the dual-clutch automatic transmission is engaged in each gear, the magnitude of the rotational inertia of each part serving as an equivalent factor is calculated.

10. The construction method according to claim 7, characterized in that: Building a dual-clutch automatic transmission module also includes a dual-clutch module modeling step, and the dual-clutch module modeling step includes: Determine the dynamic friction coefficient of the clutch according to the obtained clutch pressure P and the speed difference between the driving and driven discs; Get the inner diameter R of the friction surface of the clutch 内 , Friction surface outer diameter R 外 and the number of friction surfaces N; Take the smaller value of the dynamic friction coefficient and the static friction coefficient as μ, and according to the clutch torque formula Build the dual clutch module.

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