Research on cooperative control strategy and vibration trajectory of dual-drive flip-flow screens

Abstract

The vibration trajectory of the vibrating flip-flow screen (VFFS) is a crucial factor affecting the motion of the material. By regulating the vibration trajectory, efficient screening of material with different characteristics can be achieved. However, more research is needed on the regulation of vibration trajectories in VFFS. This article presents a five-degree-of-freedom dynamic model of VFFS, and the least squares method was used to solve the parametric model of the vibration trajectory. Based on this, a cooperative control method for the speed and phase difference of dual motors was developed. The speed synchronization and phase difference controllers were designed using cross-coupling control and optimal control algorithm, and the performance of the control system was validated by experiment. The effect of excitation parameters on the vibration trajectory’s characteristic parameters was studied. The results show that the designed cooperative control strategy exhibits good control performance and response speed in regulating speed and phase difference. By regulating the excitation parameters of the dual-drive system, effective control of the VFFS’s vibration trajectory was achieved. As the driving frequency increases, the vibration direction angle θ, the amplitude of the main vibration direction a, and the eccentricity e of both the main screen frame (MSF) and floating screen frame (FSF) decrease. As the phase difference increases, θ, a, and e at the feed end of both MSF and FSF first decrease and then increase, while at the discharge end, θ, a, and e all increase. This study provides a comprehensive solution for the vibration trajectory control of the VFFS.