具有大容量蓄能器的输送机张紧装置压力控制研究

摘要

The working conditions of belt conveyors were analyzed and the working principle of the hydraulic take⁃up device was introduced. The research emphasis was the pressure control under the working condition switch from the run tension control to tail car tension control. During such switches, the larger discharging flow of the large sizing accumulator required the hydraulic components with larger size. If the flow saturation occured, the pressure oscillation in the closed loop pressure control was easily caused. A control strat⁃egy was presented in which an open loop pressure reduction strategy was applied firstly, and then a closed loop constant pressure control was utilized. Simulation shows hydraulic components flow should meet the requirement of 500 L/min if a single closed loop control strat⁃egy is applied, while, for the present control strategy, the maximum flow is 60 L/min, relief valve size can be reduced a lot. Further⁃more, the dynamic performance of pressure control is also improved.%分析带式输送机的工况，给出张紧装置的工作原理，重点研究从运行张紧力转换到尾车升降张紧力的压力控制。在此过程中，由于大容量蓄能器的排液流量较大，因此对系统元件的通径要求较高，如果元件流量饱和，则容易在闭环控制时产生振荡等问题，针对此问题提出先开环缓慢降压、再闭环稳压控制的方法。仿真分析表明：采用直接闭环控制的方法，液压元件需满足的最大流量是500 L／min，而按所提出的方法，液压元件需满足的最大流量是60 L／min，大大减小溢流阀通径要求；从压力控制动态性能来看，文中所提方法压力波动更小。