High-power gears are widely used in various engineering fields. A gear transmission system is an extremely complex elastic system that produces complex vibrations under internal and external excitation. In this study, the excitation value in the gear was obtained based on the dynamic characteristics, stiffness, and error excitation, which were used as the input signals of the discrete element analysis. The dynamic model of the gear transmission system was established using the discrete element method. Meanwhile, the gear transmission energy was dissipated through the configuration of a particle damper in the gear. The continuous-discontinuous dynamic coupling method, which is the equivalent displacement mapping of gear contact loads from the discontinuous domain to the continuous element node, was realised, and the transformation of the local coordinates to the global coordinates was conducted. Finally, the effect of the particle restitution coefficient on the vibration reduction of gearboxes at various speeds was explored and verified through an experiment. At low rotating speeds, the best vibration reduction effect was achieved when the particle restitution coefficient was 0.2. At high rotating speeds, the best restitution coefficient was 0.7.
