Passive Suppression of Planetary Gear Transmission Vibration via Discrete Boundary Struts

This paper investigates a passive vibration suppression method for planetary gear transmissions by establishing a new PGT structural dynamics model with elastic ring gear supported by discrete boundary struts. Even with the assumption of constant mesh stiffnesses, the system is still periodically time-varying due to the dynamic interaction of the discrete boundary support struts, rotating planets and the elastic ring gear. The assume-modes method, Floquet theorem and harmonic balance method are used to obtain the steady state response of the system under constant load torque. Three criteria, maximum ring stress, planet bearing deformation force and mesh forces, are used to evaluate the vibration of the PGT driveline system. By adjusting the boundary strut number and stiffness over the entire operation speed range, some vibration suppression can be achieved. The results characterized the effects of boundary strut number and stiffness on PGT driveline vibration suppression.