Reliability Analysis of Battery Electric Vehicle High-Speed Gear Transmission Considering Correlation of Multiple Failure Modes

The transmission gear of battery electric vehicle has high input speed and various failure forms. To investigate the correlation of failure modes and their influence on gear reliability, the high-speed helical gear of a battery electric vehicle reducer is taken as the research object. Firstly, the static strength and steady-state thermal analysis are carried out, and then the probability distribution of stress is obtained through Six Sigma analysis under a single failure mode. Finally, based on the ternary Copula function, the reliability of battery electric vehicle gears considering the correlation of contact fatigue, bending fatigue and gluing is analyzed. Results shows that the correlation between failure modes of transmission gear has a certain influence on its reliability, and the reliability calculation considering multi-mode failure correlation is closer to the actual situation. This research will provide reference for the design and manufacture of high reliability transmission gear of battery electric vehicle.