Simulation of Relay Control Systems of Conveyor Speed

The possibilities of relay systems for the conveyor speed regulating are considered. Analytic equations are obtained for calculating the optimal values of the conveyor speed without a loading hopper through a statistical evaluation of the cargo flow over the observation period. Computational procedures have been developed for simulating the relay speed control of a conveyor with a loading hopper and without it, with a discrete representation of the incoming cargo flow. The aim of simulation is to check the efficiency of the algorithm for the conveyor speed regulating, to determine the optimum control parameters that correspond to the incoming cargo flow. As criteria of the regulation efficiency, the average value of the speed and the number of speed switching during the simulation are adopted. The estimations of the sample period necessary for the incoming cargo flow modeling are obtained. Examples of simulation of the relay speed control of a conveyor with a loading hopper and without it within Mathcad application are considered. It is shown that the average speed is most noticeably reduced with two- and three-stage regulation. A further increase in the number of control stages slightly reduces the average speed, but significantly increases the rate of speed switching. The installation of a loading hopper can significantly reduce the required nominal productivity of the conveyor and the average speed. The results of the work can be used in the design of conveyor drives with a relay speed control systems.