包装机混合式定量称量系统设计

目的克服单纯的容积式定量与称量式定量的缺陷,以及包装机定量称量系统的时滞性问题。方法通过分析包装机的工作原理以及影响其称量精度与速度的因素,采用混合式定量的方法,并采用双自由度Smith预估补偿,从而克服传统Smith预估器对参数模型精度要求较高的缺陷。结果仿真证明双自由度Smith预估器控制时波动较小,在时间为10 s时即可到达稳态,且有外在扰动时系统超调比传统Smith控制缩减1倍。结论通过Matlab进行了仿真研究,表明双自由度Smith预估补偿可减少称量系统的质量误差,大大提高了系统输出的精度,可显著改善定量称量包装系统的控制效果。

Design of Hybrid Quantitative Weighing System for Packaging Machine

The work aims to overcome the defects of the simple packaging metering devices of volume and weighing, and the time lag of the quantitative weighing system of the packing machine. By analyzing the working principle of the packing machine and the factors affecting its weighing precision and speed, the composite ration method and the double freedom Smith predictor were adopted to overcome the shortcomings of the traditional Smith predictor for the high precision of the parameter model. Simulation proved that the double freedom Smith prediction controlled less volatile and reached the steady state when time was 10 s. When there was external disturbance, the system overshoot was 1 time less than traditional Smith control. In conclusion, through Matlab simulation, the results show that double freedom Smith predictor can reduce the weight error of the weighing system and greatly improve the accuracy of the system output, and can significantly improve the control effect of the quantitative weighing and packing system.