| With the introduction of my country’s "two carbons" goals and the continuous advancement of the industrialization process,the promotion and application of new energy heavy-duty commercial vehicles has become an important measure for my country’s energy and power transformation.As the core component of the new energy heavy-duty vehicles wheel-side reducer,the contact performance and dynamic characteristics of the planetary gear system directly affect the development of new energy vehicle gears.At present,the research on the contact characteristics and dynamic characteristics of the gear transmission system has been relatively mature,but the research on the transient contact characteristics and dynamic characteristics of the gears of new energy vehicles is still not systematic.Therefore,gear contact theory,dynamics theory,finite element method and virtual prototype technology are used in this paper to carry out research on the contact characteristics and dynamic characteristics of new energy vehicles planetary gear reducers.The main research contents are as follows:（1）Combined with the gear contact theory and the finite element method,the finite element analysis model of the planetary gear reducer is established,using the transient dynamic analysis method,the transient contact characteristics of each gear of the fuel and new energy heavy-duty vehicles wheel-side reducer under different loads and starting speeds are compared and analyzed,the influence of nonlinear factors on the transient contact characteristics of the new energy heavy-duty vehicles wheel-side reducer is further analyzed.（2）Consider the situation where the gear contact performance of new energy vehicles is poor,the causes and distribution characteristics of gear pitting failure are systematically analyzed,the calculation method of gear mesh stiffness is summarized,the calculation model of pitting gear contact stiffness and the dynamic equation of planetary gear system are established,the change law of the natural frequency and amplitude of the planetary gear system before and after pitting is explored.（3）Based on the dynamic theory,a virtual prototype platform of the planetary gear reducer is built,the dynamic contact model of the planetary gear reducer is established,the time and frequency domain characteristics and load sharing characteristics of the external meshing contact force of the single-tooth pitting planetary gear system are studied;The pitting corrosion of multi-tooth surface is considered,and the variation law of external meshing contact force in time and frequency domain of concentrated and uniformly distributed multi-tooth pitting planetary gear system is further analyzed.（4）Based on the flexible body theory,a rigid-flexible coupling model of the planetary gear reducer is established,and the variation law of vibration deformation and vibration acceleration of the planetary gear system before and after pitting is analyzed;considering the stiffness of the planetary gear support member,the influence of the material stiffness of the planetary gear pin shaft on the vibration characteristics of the planetary gear system is further studied. |
