Study On Dynamics And Sharing Load Characteristics Of Split Power Planetary Gear Transmission System

The split power planetary gear transmission system is one of the most importantcomponents in the ship drive sysyem. The entire system is composed of a differential stage anda closed stage gear transmission system; gear transmission is the important noise source. It hasan important signification to research dynamic and split power to reduce noise of warship.The multiple degrees of freedom coupling nonlinear dynamics model of the split powerplanetary gear transmission system is constructed. The process of dynamics model constructionconsiders the nonlinear element of transmission system; the nonlinear element includestime-varying mesh stiffness, meshing error, damping and bearing support stiffness and so on,the nonlinear dynamics model is builded of the entire transmission system by the lumped massparameter method. The mesh stiffness and meshing error excitations of gear train must becomputed in process of dynamics analysis. The static stiffness experiment is carried out of theplanetary transmission to test and verify the stiffness computing method; the time varyingmeshing error can be expressed by the increment method of mesh action line. The constructionof system dynamics model is the foundation to the following research.The power distribution characteristics are researched of split power planetary geartransmission system on the basis of the system dynamics model. In the paper, the statics loadsharing characteristics and dynamics sharing characteriscs are studied firstly. The relation isresearched between manufacture errors, assembly error and the transmission system loadsharing coefficient and some valuable conclusion will be obtained. At last, the influence isstudied of input power, input speed, the number of planet gear to load sharing coefficient ofsub-system.The dimensionless dynamics differential equation is solved by the Runge-Kutta numericalintegral method, the nonlinear dynamics response of the transmission system is researchedprofoundly by the displacement of the time domain response, phase diagram, Poincare map andbifurcation diagram. The system parameters include mesh stiffness, mesh error and dampingratio.The contact analysis of single gear train is studied on the gear modification research of planetary transmission system and the gear optimization modification is researched accordingto transmission error lowest on the basis of structure characteristic. Modification experiment iscarried out of the helical gear to testify validity of the modification method.At last, the optimization modification method is applied to planetary gear transmissionsystem and the dynamics characteristics are compared of differential class transmission systemunder gear modified and unmodified. The results show that transmission error fluctuation isreduced when gear is modified, it can improve obviously dynamics characteristics of gearsystem, they include mesh stiffness and mesh dynamics load and gear surface stress and so on.