组合秤下料机构自适应控制

Self-adaptive Control System for Feeding Mechanism of the Combination Weigher

目的研究组合秤下料机构参数缓慢时变导致的下料量偏差大的自适应控制方法。方法采用模型参考自适应控制对下料速度的偏差进行补偿,给出模型参考自适应控制器的设计方法,并采用Matlab软件进行仿真。结果当模拟下料机构在1 s之后发生机构参数变化时,在2 s内无自适应控制系统下料量与参考模型下料量的偏差随时间增加而比例增大,在2 s时相对误差达41.38%;采用自适应控制系统,其下料量偏差稳定,在2 s时相对误差为3.36%。结论组合秤下料机构采用自适应控制系统,能够有效减少由于参数缓慢时变引起的下料量偏差。

The aim of this work was to study the self-adaptive control system which could reduce the large deviations of the combination weigher＇ s feeding amount that was caused by the slow change of feeding mechanism＇ s parameters. This paper allowed the model reference adaptive control （MRAC） system to compensate for the deviations of the feeding speed, proposed the design method of the MRAC system for feeding mechanism, and performed simulation with the Matlab software. Assuming that the parameters of feeding mechanism changed at ls, without the MRAC system, the deviations of feeding amount increased with the time within 2 s, and the relative error reached the maximum value of 41.38 % at 2 s. With the MRAC system, the deviations of feeding amount kept stable, and the relative error was 3.36 % at 2 s. When the MRAC system was adopted for the feeding mechanism of combination weigher, the feeding amount deviations caused by the slow change of the mechanism＇ s parameters could be effectively reduced.