Study On The Test Bench Of Hydro-Mechanical Transmission In Heavy-Duty Vehicle

Heavy-duty vehicle has the characteristics of high engine power, bad driving condition and large load impact. This puts forward higher request to gearbox, which is the most important part of the vehicle transmission system. Hydro-mechanical transmission has the feathers of large transmission torque, strong overload ability and load adaptability, which is especially suitable for heavy-duty vehicle. At present, compared with foreign countries, the key technology and industrialization ability of hydro-mechanical transmission in our country is far behind. The study on the test bench of hydro-mechanical transmission in heavy-duty vehicle will have great significant for the research and development of hydro-mechanical transmission in our country.With the support of research about comprehensive performance test bench for high power transmission system in an institute, this paper studies the test bench of hydro-mechanical transmission in heavy-duty vehicle on the basis of existing researches. The mainly contributions of this paper include the following aspects.(1) Taking 9 speed manual hydro-mechanical transmission as the object, this paper gives an introduction about the structure and principle of it. The combination operating curve of engine and hydro-mechanical transmission is obtained through the analysis about their work characteristics. A Simulink model is built to simulate the working process and performance of hydro-mechanical transmission.(2) According to the requirements of the test system, common DC bus electric closed test bench is chosen as the form of this test system after the analysis and comparison of several test bench forms. The overall plan of the test system is designed and the main components of the system are introduced. In addition, research on the key technologies of the test system, such as the motor control method and the communication method, are carried out.(3) This section introduces the realization process of this test system, including the powertrain system, the PLC monitoring system, the data acquisition system and the control system. Finally, the test system is proved to be able to meet the requirements according to the curves of the test process.