Research Of Hardware-in-the-Loop Test System For Uninterrupted Shift Transmission

Uninterrupted Shift Transmission(UST) is a novel kind of automatic transmission, which is proposed by our country in recent years. UST is based on the special speed relationship of the parallel shaft-gears. With the reasonable assembly of controlled One Way clutch(COWC), UST realizes torque uninterrupted shift. The shift process of UST not only overcomes the inhered torque interrupt drawback of automated manual transmission(AMT), but also avoids the precise clutch-clutch overlapping control of dual clutch transmission(DCT).Hardware-in-the-loop(HIL) test system is widely used in testing the performance of automatic transmission and verifying the control strategy of the electronic control unit. With establishing the HIL test system, the main research work of this paper is as follows:At first, study the general structure scheme of UST. Then introduce the structure and kinematic characteristics of multimode controlled shifter(MCS) and linkage shifting device. Meanwhile, analyzing the UST shift principles and designing dual MCS control methods for diversified vehicle working conditions.Secondly, the UST driveline system model including mean value engine model(MVEM), clutch, MCS, vehicle and shifting motor is built based on Matlab/Simulink software.GTPOWER is used to identify the undetermined parameters of MVEM. Then analyzing dynamic characteristic of MVEM and the shift motor. The shift schedules of UST have been designed at last.Thirdly, the simulation of UST vehicle performance has been carried out based on the UST driveline system model. The simulation results show that the UST has badly shift quality in shifting process. In order to improve the shift quality of UST, the optimal control theory based on minimum principle is proposed to optimize the shift quality of UST. UST optimal upshift control strategy has been designed and applied in the simulation model. By the comparison and analysis of the different simulation, the designed control strategy has been validated effective to decrease the shift shock and control the sliding friction work in a reasonable range.Finally, the HIL test system of UST has been built based on Real-Time Windows Target. And the functional properties of the test system is verified by the hardware-in-the-loop test of UST. The experimental results show that the HIL test system can meet the real-time request of the electronic control unit. The full vehicle dynamic model can carry out the shift action according to the shift schedule and its shift quality is very good. Therefore the electronic control unit has good control effect in the shifting process.The HIL test system is designed in this paper will not only provide a new solution for the performance test of UST, but also provide a reference for other kinds of automatic transmission to build HIL test system.