Study On Theory And Application Of Reweighting Electro-Hydraulic Control In The Loading System

This paper is from a project,named as"the research of reweighting hydraulic control of the ore loading system", exploited by Yanshan University and Qinhuangdao Port Group Corporation.Along with the demand of development railway bulk frtight, it needs more and more requirement for railway vehicle loading system. The loading system is a neotype and specialized loading machinery, widely used in many trades especially in the ports, and lays weight on the bulk frtight such as ore and coal. Weighing system is the hardcore of the loading system, and it directly influences on precision and automaticity of loading. Wherefore, there are many important theory and practice senses for this research.In this pager, the developments of the ore loading system both here and abroad are summarized, and the main structures and function of the ore load out system are introduced and a scheme of the reweighting system, in which electro-hydraulic proportional position system is designed to control unload strobe of weighting bin, is proposed for the problems and defects of the weighting control system, in order to realize the accuracy control of the loading materials.In this pager, adopting the means of modelling by mechanism, non-linear mathematical model of the reweighing electro-hydraulic control system is established, and based on it, modularized and non-linear simulation model is carried out, in MATLAB/Simulink environment and Stateflow module. In simulation research, the means of subsection PID control is adopted, and PID parameters can be optimized by the Nonlinear Control Design module(NCD). In addition, the non-linearity factors effecting on control accuracy of discharge gates such as dead band, saturation and friction are detailedlyanalysed.The experiment test is carried out at last in the paper. The experiment control system is used to realize dynamic detection and real-time control by industrial computer system. In this pager, by VB6.0 and database technology, the software of the reweighing electro-hydraulic control system is developed which has the worth of practical application. It is realized that the demand of control in working conditions of no overage, more surplus material and less surplus material. The results of the final experiment indicate that the design method of mathematical models and control system are correct and feasible.