Study On The Design Of The Measurement And Control System Of Electrically Closed Gearbox Test Bench

In recent years, automobile industry has been developing very rapidly in China. Its prosperityexerts a significant influence on promoting the national economy development and improvingpeople’s living standards. Meanwhile, the problems of traffic safety, energy and environment,which are caused by automobile, are increasingly becoming people’s concern. Therefore, moreand more people pay attention to the automotive quality. Gearbox serves as the core component ofautomotive transmission, whose performance has an important effect on the quality of automobile.Therefore, it is extremely important for the improvement of gearbox’s quality to promote car’stransmission power, economical efficiency and security. As an important device for detecting itstransmission performance, gearbox test bench provides the material guarantee for the design andimprovement of gearbox.The case of the thesis comes from a400kW alternating current (ac) enclosed transmissionintegrated test-bench of a Gear Co., Ltd. The test-bench is designed for huge commercial vehiclestransmission performance experiment and test, aiming at developing a transmission test-bed withhigh control accuracy, accurate test, and simple structure, low cost and high automation.This thesis first explores the significance of the transmission test bench and expounds thecurrent situation of test bench development. Secondly, according to the function of every part, thetest bench is divided into four sub-systems, including mechanical system, the DC bus system,controlling control system and testing system. After the detailed analysis of DC bus technology,the DC bus system design principles are summarized, based on which the DC bus system of theexperiment station is designed. Meanwhile, the various components’ selection of the DC bussystem is also accomplished.This thesis also studies the motor control system with PLC as the core and makes a briefintroduction of the structure, control theory, programming procedures of the PLC and thetest-bench’s motor control program. In addition, the communication problems between PLC andthe drive equipment, industrial machines are studied as well. For instance, the test principle of thetest system hardware is introduced, the software program of some test system is made, and virtualinstrument technology which is developed on the basis of LabVIEW is also illustrated, signalacquisition and processing are carried out in detail.At present, the test bench, which is with stable mechanical structure, has been built. Thenormal motor enables to accomplish the required tasks; DC bus system can realize the recycling ofelectrical energy with quick brake response; oil temperature control system can completely control the temperature; test system can achieve signal acquisition with a higher accuracy, meeting thedemands of the control task; the system software can fulfill transmission experiments officers’login, parameter setting, data collection and analysis, data storage and other functions.