Running-in Test Methods And Bench Development For New Energy Vehicles Transmission

In the transformation process from traditional automobile industry to new energy automobile industry,the transmission has experienced a circuitously rising development of”unnecessary?reuse?innovative use ".It has gradually become a key and indispensable component of new energy vehicles driving system.The running-in test of the transmission can eliminate early stage failures,improve the working condition of motion pairs,and preliminarily test the quality of the assembly,thereby improving its performance.Further more,it can improve the power,handling stability,economy and safety of new energy vehicles.However,there is a problem of neglecting the importance,inefficiency and ineffectiveness of running-in test of new energy vehicle transmissions.Therefore,it is of great theoretical and practical benefit to study the running-in test method and develop the transmission bench for new energy vehicles.This paper takes DAT transmission as the research object,studies and analyzes its running-in test method and test bench,and the main works are as follows:First of all,the driving system of new energy vehicles,transmission structure,running-in test purpose,test parameters,test methods and test bench type are studied theoretically.And presents an energy saving and highly efficient running-in test method to mutual drag and grind gear surfaces with symmetrical arrangement,thus the overall design plan of running-in test is determined.Secondly,the construction of the running-in bench for the transmission includes:? Structural design of the mechanical system of the bench.The mechanical structure of the bench is designed,and the static strength checking and modal analysis of key components are carried out.? Hardware design of bench control system.The hardware selection and design of energy recovery device,the frequency conversion control system,the data acquisition system and the oil temperature cooling system are carried out.? Software design of bench control system.The communication system based on CAN bus is built,and the software part of the control system is designed by using the virtual instrument LabVIEW.The function of control,real-time monitoring of parameter and data processing is realized in the upper computer.Finally,the test specification for the transmission running-in is established,and the test of unloading and loading conditions is carried out.During the test,important parameters such as speed,torque and oil temperature are monitored in real time,and the system energy recovery,test data and running-in effect are analyzed.In this paper,a running-in test method for new energy vehicle transmission is studied and a test bench is built,which can be used for running-in the positive and negative gear surface of two transmission simultaneously,achieving the bi-directional grinding of the transmission gear surface.The running-in test of transmission can improve the quality of gear surface effectively,form a high reliability,good abrasion and smooth of gear surface.Thus,the feasibility,validity and rationality of the test method and bench proposed are verified.