Silent chain is widely used in the field of mechanical transmission. Compared with ordinary chain transmission, it has prominent advantages such as high precision, low noise, and being suitable for high speed and heavy loads. Based on the design concept of intelligent dynamics, the phase variation is carried out. The multiphase transmission silent chain retains the original advantages of the single-phase transmission silent chain, and its structure bearing capacity is improved, the polygon effect is reduced, and the fluctuation, noise, and vibration of elastic edge are improved. Based on rigid-flexible intelligent dynamics technology, the transmission characteristics of a multiphase transmission silent chain system were studied. In this paper, the meshing contact force between the chain plate and the sprocket is described in detail, and the 3d model and dynamic model of the multiphase transmission silent chain are established. Topological optimization method was used to design the lightweight of the multiphase transmission silent chain, and the existing target of lightweight was realized. The dynamics simulation was carried out to extract the dynamics data and analyze the dynamics characteristics such as tight edge fluctuation, instantaneous transmission ratio, and meshing contact force. The results show that the model correctly predicts the dynamic behavior of the system, and the high speed inhibits the lateral fluctuation of the system. The peak value of meshing contact force increases with the increase of rotational speed, and the multiphase drive can be used in practical control system design.