Research On Measurement And Control System Of The Automated Transmission Object-in-the-loop System

As one of the hallmarks of modern automobile development,the performance of its controller TCU directly affects performance indicators such as power and economy of the car.Therefore,the development of TCU is the core and technical bottleneck in the development of automatic transmissions.Performance and function testing is a very important part of the product development process.At present,indoor testing of automatic transmissions is mainly focused on bench testing and HiL testing.Bench testing is more used for performance testing of the gearbox body.HiL testing can only performs some functional and trend verifications on the controller TCU.Based on this,the research group proposed a test scheme for object-in-the-loop test system of the automatic transmission,which combined the HiL simulation platform and the high-performance test rig to simulate the real vehicle operating environment that the test object was facing.Quickly develop and verify the control strategy of the TCU,and complete part of the TCU calibration and matching work indoors in the later stages of development.The automatic transmission has a high degree of integration of the physical-in-the-loop system.The measurement and control system takes computer technology as the core and integrates control and measurement to realize the automatic control of the test bench by the simulation model.In order to ensure the control accuracy and response speed and improve the control performance,this paper mainly focuses on the measurement and control system of the physical transmission system of the automatic transmission.The thesis first analyzes the object-in-the-loop system architecture and principle of automatic transmission,proposes the functional requirements of the measurement and control system and designs the overall plan of the measurement and control system;secondly,establishes a CAN bus communication network between the real-time simulation platform LabCar and the test bench,and sets up FIR low-pass filtering The device performs digital filtering on the sampled data,and develops a complete set of object-in-the-loop simulation models and measurement and control pages to realize the automatic control of the test bench by the simulation model.Then,the response characteristics of the automatic transmission test bench were analyzed through experiments.It was found that the drive and load motors could not strictly follow the target instructions calculated in real time by the simulation model,which showed a certain time lag and amplitude attenuation.Based on this,a control link based on the feedforward-feedback composite control algorithm is designed to track and correct the target instruction,and the correction control effect is simulated and analyzed.Next,the decoupling control is performed on the test bed driving speed and load torque correlation system,and the coupling relationship between the speed and torque is estimated by experimental analysis and curve fitting,and designed speed and torque decoupling compensator based on feedforward compensation decoupling.Finally,according to the performance indicators of the test bench,appropriate test conditions are selected,and object-in-the-loop simulation tests are performed on the speed controller,torque controller,and decoupling compensator.