224 / 2021-04-09 03:13:20

A study of dynamic responses and chaos control of gear transmission system in locomotive under influence of track irregularity

Nonlinear dynamic; Locomotive gear; Track irregularity; Chaos control

In this study, the dynamic responses of gear transmission system in a locomotive are examined incorporating the influence of track irregularity. A multi-degree-of-freedom mathematical model of spur gear system is established using the lumped mass method. The internal and external excitations, such as backlash, time varying mesh stiffness, gear eccentricity, roll bearing forces and input/output torque are included in this transverse-torsional dynamic model. The simulation of track-to-wheelset reaction torque which reflects the track irregularity fluctuation is carried out by establishing the locomotive dynamic model. Then, some sensitive parameters are selected to analyze the motion states of the locomotive gear transmission system. The results show that the locomotive gear transmission system appears unstable states under some certain parameters. In order to avoid the undesirable vibration behaviors, a dry friction damper is adopted to control or suppress the chaotic motions of dynamic responses. The linear feedback and periodic excitation non-feedback control strategies are respectively employed to design the actuator of dry friction damper. In addition, a comparison is made to verify the contribution of feedback and non-feedback control method used in this system. It is indicated that undesirable behaviors of the locomotive gear transmission system can be avoided effectively by utilizing the proposed control method.