CN102353535B - Low-power-consumption hardware-in-loop test platform and method for stepless speed changer of vehicle - Google Patents
Low-power-consumption hardware-in-loop test platform and method for stepless speed changer of vehicle Download PDFInfo
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- CN102353535B CN102353535B CN 201110183568 CN201110183568A CN102353535B CN 102353535 B CN102353535 B CN 102353535B CN 201110183568 CN201110183568 CN 201110183568 CN 201110183568 A CN201110183568 A CN 201110183568A CN 102353535 B CN102353535 B CN 102353535B
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Abstract
The invention discloses a low-power-consumption hardware-in-loop test platform and a low-power-consumption hardware-in-loop test method for a stepless speed changer of a vehicle. The test platform comprises a target machine, a host machine, a data acquisition unit and a hardware unit, wherein the hardware unit comprises a drive motor, the stepless speed changer and a load motor which are connected with one another sequentially; a simulink vehicle transmission model is established in the host machine, and is downloaded to the target machine by using a release to manufacture (RTM) compilation model during operation; the target machine is respectively connected with frequency converters corresponding to the drive motor and the load motor, and makes the drive motor have rotating speed characteristics which are the same as those of an engine and the operation condition of the load motor approach the operation condition of an actual vehicle by setting a simulation coefficient of the vehicle transmission model; and the data acquisition unit is used for acquiring operation data of the stepless speed changer and outputting the data. By stressed balance of a speed changing mechanism of the stepless speed changer, when the properties of a control system and a hydraulic system are researched, a low-power drive motor and a low-power load motor are used for replacing the engine and high-power loading equipment, and the speed changer is operated in a no-load/light-load state, so that the construction cost of the test platform is greatly reduced.
Description
Technical field
The present invention relates to speed transmission test device, be specifically related to a kind of continuously variable transmission of vehicle low-power consumption hardware the-loop test bed.
Background technology
The design object of conventional vehicles buncher testing table is to imitate as far as possible the vehicle Real-road Driving Cycle, testing table is comprised of engine, variator, flywheel, loading equipemtn etc., wherein engine can be replaced by the suitable motor of power, flywheel and loading equipemtn can be replaced by the motor that meets the demands, this test platform structure is complicated, cost is high, and in operational process, energy consumption is larger.
An at present domestic emphasis to buncher research is control system and hydraulic system, the stress balance relation that has due to the gear self of buncher, the operation conditions of hydraulic system is subjected to the impact of variator load hardly, also can carry out normal Transmission Ratio Control and clamping force control in zero load or light duty.
Build and operating cost in order to reduce test, when the efficient of buncher and steel band life-span not being studied, do not need to apply the load identical with actual condition, and all can as long as guarantee that rotating speed and speed ratio variation etc. and truth approach.Change power source into low-power machine, only need to guarantee that variator can get final product in zero load or light duty operation, loading equipemtn also changes low-power machine into, reduces simultaneously or cancel mass flywheel, thereby greatly reduces the testing table construction cost.
Rapid control prototyping is the trend of present control strategy and control algolithm research, commercial podium is more expensive, therefore the xPC target Functional Design continuously variable transmission of vehicle low-power consumption hardware that utilizes MATLAB software the-loop test bed be a kind of considerable cost effective method, and buncher hardware based on zero load/underloading is not arranged the-loop test bed at present.
Summary of the invention
In view of this, one of purpose of the present invention is to provide a kind of continuously variable transmission of vehicle low-power consumption hardware the-loop test bed, utilize the stress balance relation that in buncher, gear self has, when carrying out control system and hydraulic system performance study, adopt miniwatt drive motor and load motor to replace engine and high-power loading equipemtn, greatly reduce the construction cost of testing table; Two of purpose of the present invention has been to provide a kind of continuously variable transmission of vehicle low-power consumption hardware in the ring test method.
The objective of the invention is to be achieved through the following technical solutions:
This continuously variable transmission of vehicle low-power consumption hardware is the-loop test bed, and described testing table comprises target machine, host, data acquisition unit and hardware cell;
Described hardware cell comprises drive motor, buncher and the load motor that connects successively, set up simulink system of vehicle transmission model in described host, the simulation parameter of described system of vehicle transmission model is inputted by host, during operation, utilizes the RTW compilation model to be downloaded to target machine;
Described target machine by different communication interfaces respectively with drive motor and load motor control linkage, by the setting to the simulation parameter of system of vehicle transmission model, target machine makes drive motor have the rotary speed property identical with engine, and the working order of load motor is moved close to real vehicle;
Described data acquisition unit is by clamping force and the driven wheel tach signal of the true CVT of sensor collection, input system of vehicle transmission realistic model, the control effect that is used for research clamping force control algorithm and Transmission Ratio Control algorithm, and be used for calculating the speed of a motor vehicle and engine speed, the data obtained is saved to target machine or is uploaded to host.
Further, described control module is realized the rotating speed of drive motor and load motor is controlled by frequency converter I and frequency converter II respectively;
Further, described data acquisition unit comprises capture card and CVT interface board, and described CVT interface board is connected with sensor output terminal on buncher, and exports by capture card the service data that gathers to target machine;
Further, described simulink system of vehicle transmission model comprises driver, engine, controller, running resistance, vehicle dynamics, motion-control module.
Further, described simulation parameter comprises engine, CVT and road conditions parameter, calculation engine torque, running resistance, speed ratio and system pressure, and further calculate target vehicle speed and target engine speed.
Two of purpose of the present invention is achieved through the following technical solutions:
This continuously variable transmission of vehicle low-power consumption hardware comprises the following steps in the ring test method:
1) drive motor, buncher and load motor are connected successively, form hardware cell;
2) set up simulink system of vehicle transmission model in host, and the simulation parameter of input system of vehicle transmission model, utilize the RTW compilation model to be downloaded to target machine;
3) run-time target program, the hardware cell entry into service, drive motor has the rotary speed property identical with engine, and the working order of load motor is moved close to real vehicle;
4) data acquisition unit is by clamping force and the principal and subordinate wheel tach signal of the true CVT of sensor collection, input system of vehicle transmission realistic model, the control effect that is used for research clamping force control algorithm and Transmission Ratio Control algorithm, and be used for calculating the speed of a motor vehicle and engine speed, the data obtained is saved to target machine or is uploaded to host.
The invention has the beneficial effects as follows:
1. utilize the stress balance relation that in buncher, gear self has, when carrying out control system and hydraulic system performance study, adopt miniwatt drive motor and load motor to replace engine and high-power loading equipemtn, variator is in zero load/light condition operation, greatly reduces the construction cost of testing table;
2. for pure model emulation system, the present invention is included in hardware among ring with variator, improves running precision;
3. the present invention adopts host based on xPC-target machine structure, the real-time of assurance system operation.
4. this system jointly controls variator and motor, make motor have the rotary speed property identical with engine by controlling frequency converter, while control load motor, working order and the real vehicle operation of testing table are approached, most of function with conventional test platform comprises exploitation and access control strategy and control algolithm, is convenient to hydraulic actuating mechanism is carried out performance test and analysis, realized low energy consumption, low cost.
Other advantages of the present invention, target and feature will be set forth to a certain extent in the following description, and to a certain extent, based on being apparent to those skilled in the art to investigating hereinafter, perhaps can be instructed from the practice of the present invention.Target of the present invention and other advantages can realize and obtain by following instructions and claims.
Description of drawings
In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is described in further detail below in conjunction with accompanying drawing, wherein:
Fig. 1 is test platform structure sketch of the present invention;
Fig. 2 is the kinetic model schematic diagram under clutch coupling of the present invention and torque converter locking operating mode.
Embodiment
Hereinafter with reference to accompanying drawing, the preferred embodiments of the present invention are described in detail.Should be appreciated that preferred embodiment only for the present invention is described, rather than in order to limit protection scope of the present invention.
As shown in Figure 1, continuously variable transmission of vehicle low-power consumption hardware of the present invention comprises host 1, target machine 2, data acquisition unit 3 and hardware cell the-loop test bed;
Hardware cell comprises drive motor 5, buncher 6 and the load motor 7 that connects successively, by at the interior simulink system of vehicle transmission model of setting up of host 1, the simulation parameter of described system of vehicle transmission model is inputted by host, during operation, utilizes the RTW compilation model to be downloaded to target machine;
RTW is the tool software of MATLAB, can and automatically be downloaded to target machine with the compiling of simulink model.
XPC is the functional module of simulink, is used for realizing that the hardware of a kind of host-target machine formula is at ring structure, wherein, target machine is the universal PC compatible, set up the simulink model on host, after compiling by RTW, be downloaded to target machine and real time execution.Target machine is bare machine, need not the operating systems such as windows, and only the model program after the operation compiling, guaranteed travelling speed, therefore can real time execution.
Target machine by different communication interfaces respectively with drive motor and load motor control linkage, simulink system of vehicle transmission model comprises driver, engine, controller, running resistance, vehicle dynamics, motion-control module.By the setting (simulation parameter comprises engine, CVT and road conditions parameter) to the simulation parameter of system of vehicle transmission model, calculation engine torque, running resistance, speed ratio and system pressure, and further calculate target vehicle speed and target engine speed.
Target machine makes drive motor have the rotary speed property identical with engine, and the working order of load motor is moved close to real vehicle; In the present embodiment, control module is realized the rotating speed of drive motor and load motor is controlled by frequency converter I 8 and frequency converter II 9 respectively.
Described data acquisition unit gathers the service data of buncher by sensor, and the output data are saved to target machine or are uploaded to host.In the present embodiment, data acquisition unit comprises capture card and CVT interface board 4, and CVT interface board 4 is connected with sensor output terminal on buncher, and exports by capture card the service data that gathers to target machine.
Simulink is a kind of Visual Simulation Tools in MATLAB, it is a kind of block diagram design environment based on MATLAB, be a software package realizing Modelling of Dynamic System, emulation and analysis, be widely used in the modeling and simulation of linear system, nonlinear system, digital control and digital signal processing.Simulink can carry out modeling with the sampling time of continuous sampling time, discrete sampling time or two kinds of mixing, and it also supports multirate system, and namely the different piece in system has different sampling rates.In order to create dynamic system model, Simulink provides a graphical user interface (GUI) of setting up the model calcspar, this constructive process only need be clicked and drag mouse action and just can complete, it provides a kind of faster, straightforward mode, and the user can see the simulation result of system immediately.
With the pure realistic model that moves on PC fully relatively, continuously variable transmission of vehicle low-power consumption hardware of the present invention has a following characteristic the-loop test bed:
1) replace the CVT model with actual CVT, its simulated effect and pure software environmental facies ratio are closer to truth;
2) motion-control module is according to kinematic train dynamics, the target engine speed that calculates and the speed of a motor vehicle, the moving control module for controlling frequency converter makes drive motor and load motor rotating-speed tracking target engine speed and the speed of a motor vehicle, and service performance and the actual vehicle of testing table are close;
3) the CVT interface board is the signal translation interface of CVT and capture card, converts the sensor signal on CVT to signal that capture card can gather, and the control signal according to capture card output drives solenoid valve simultaneously.Solenoid valve comprises the clamping force valve relevant with gear and speed ratio valve, wherein the clamping force valve is used for controlling the clamping force of engaged wheel, the speed ratio valve is used for controlling the clamping force of driving wheel, driving wheel and engaged wheel all are comprised of shaft collar and slider disc, regulate the clamping force ratio of principal and subordinate wheel by controlling two valves, change the radius of clean-up of driving wheel and engaged wheel, thereby realize that speed ratio continuously changes.
Based on above testing table, continuously variable transmission of vehicle low-power consumption hardware of the present invention comprises the following steps in the ring test method:
1) drive motor, buncher and load motor are connected successively, form hardware cell;
2) set up simulink system of vehicle transmission model in host, and the simulation parameter of input system of vehicle transmission model, utilize the RTW compilation model to be downloaded to target machine;
3) run-time target program, the hardware cell entry into service, drive motor has the rotary speed property identical with engine, and the working order of load motor is moved close to real vehicle;
4) process of the test is monitored, and saved the data in target machine or be uploaded to host;
5) after trial run finishes, test figure is processed.
As shown in Figure 2, clutch coupling and the torque converter kinetic model under the locking operating mode is:
In formula, speed ratio i calculates by acquisition test platform variator I/O axle rotating speed.
CVT modal a kind of structure at present is: engine-clutch coupling-torque converter-gear-main deceleration-wheel.Controlling due to Clutch Control and torque converter is current techique, it is not the distinctive technology of CVT, therefore not the emphasis of CVT research, usually the control research of CVT is mainly concentrated on the research of clutch coupling closure and torque converter locking state, the Control the content of this moment comprises Transmission Ratio Control and clamping force control, is the distinctive Control the content of CVT.
Dynamics simulation obtains engine speed and the speed of a motor vehicle respectively as the rotating speed of target of testing table drive motor and load motor.Stress balance relation due to CVT self, speed ratio rate of change and control characteristic are only relevant with rotating speed, and be irrelevant with the moment of torsion that transmits, as long as therefore make the drive motor rotary speed property identical with engine speed, the load motor rotating speed is identical with the driving wheel rotating speed, just can reflect exactly the speed ratio characteristic of CVT.
Obtain engine speed and the speed of a motor vehicle by above-mentioned equation emulation, by the engine speed that frequency converter calculates the drive motor rotating-speed tracking, regulating load motor speed, the vehicle wheel rotational speed that the tracking target speed of a motor vehicle is corresponding.This moment, CVT just was operated under the engine speed and the speed of a motor vehicle identical with actual condition.
Explanation is at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, although with reference to preferred embodiment, the present invention is had been described in detail, those of ordinary skill in the art is to be understood that, can modify or be equal to replacement technical scheme of the present invention, and not breaking away from aim and the scope of the technical program, it all should be encompassed in the middle of claim scope of the present invention.
Claims (5)
1. continuously variable transmission of vehicle low-power consumption hardware the-loop test bed, is characterized in that: described testing table comprises target machine, host, data acquisition unit and hardware cell;
Described hardware cell comprises drive motor, buncher and the load motor that connects successively, set up simulink system of vehicle transmission model in described host, the simulation parameter of described system of vehicle transmission model is inputted by host, during operation, utilizes the RTW compilation model to be downloaded to target machine;
Described target machine by different communication interfaces respectively with drive motor and load motor control linkage, by the setting to the simulation parameter of system of vehicle transmission model, target machine makes drive motor have the rotary speed property identical with engine, and the working order of load motor is moved close to real vehicle;
Described data acquisition unit is by clamping force and the driven wheel tach signal of the true CVT of sensor collection, input system of vehicle transmission realistic model, the control effect that is used for research clamping force control algorithm and Transmission Ratio Control algorithm, and be used for calculating the speed of a motor vehicle and engine speed, the data obtained is saved to target machine or is uploaded to host;
Described control module is realized the rotating speed of drive motor and load motor is controlled by frequency converter I and frequency converter II respectively.
2. continuously variable transmission of vehicle low-power consumption hardware according to claim 1 is the-loop test bed, it is characterized in that: described data acquisition unit comprises capture card and CVT interface board, described CVT interface board is connected with sensor output terminal on buncher, and exports by capture card the service data that gathers to target machine.
3. continuously variable transmission of vehicle low-power consumption hardware according to claim 1 and 2 the-loop test bed, is characterized in that: described simulink system of vehicle transmission model comprises driver, engine, controller, running resistance, vehicle dynamics, motion-control module.
4. continuously variable transmission of vehicle low-power consumption hardware according to claim 3 is the-loop test bed, it is characterized in that: simulation parameter comprises engine, CVT and road conditions parameter, be used for calculation engine torque, running resistance, speed ratio and system pressure, and further calculate target vehicle speed and target engine speed.
5. continuously variable transmission of vehicle low-power consumption hardware in the ring test method, is characterized in that: comprise the following steps:
1) drive motor, buncher and load motor are connected successively, form hardware cell;
2) set up simulink system of vehicle transmission model in host, and the simulation parameter of input system of vehicle transmission model, utilize the RTW compilation model to be downloaded to target machine;
3) run-time target program, the hardware cell entry into service, drive motor has the rotary speed property identical with engine, and the working order of load motor is moved close to real vehicle;
4) data acquisition unit is by clamping force and the driven wheel tach signal of the true CVT of sensor collection, input system of vehicle transmission realistic model, the control effect that is used for research clamping force control algorithm and Transmission Ratio Control algorithm, and be used for calculating the speed of a motor vehicle and engine speed, the data obtained is saved to target machine or is uploaded to host.
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| CN 201110183568 CN102353535B (en) | 2011-07-01 | 2011-07-01 | Low-power-consumption hardware-in-loop test platform and method for stepless speed changer of vehicle |
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Families Citing this family (7)
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| CN102323055B (en) * | 2011-07-01 | 2013-08-14 | 重庆大学 | Test stand and test method for gear shift performance of vehicle continuously variable transmission (CVT) |
| CN103092082B (en) * | 2013-01-07 | 2015-08-12 | 河南科技大学 | A kind of driver is in ring vehicle performance optimization Simulation pilot system |
| CN103776630B (en) * | 2014-02-13 | 2016-06-15 | 湘潭大学 | Metal band type stepless speed variator slip rate testboard |
| CN104655434A (en) * | 2015-02-10 | 2015-05-27 | 中国计量学院 | In-loop testing experiment method of automobile brake hardware |
| CN110068463B (en) * | 2019-03-26 | 2021-05-28 | 中国汽车技术研究中心有限公司 | Separation cooperative test method and system for automobile power assembly |
| CN110243593A (en) * | 2019-06-11 | 2019-09-17 | 中国第一汽车股份有限公司 | Automatic transmission half hitch chalaza test method, system, equipment and storage medium |
| CN113702028B (en) * | 2021-07-14 | 2024-05-10 | 柏科（常熟）电机有限公司 | Real and virtual combined full-automatic gearbox testing system and method |
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