基于模糊分数阶PID的啤酒灌装机贮液缸内液位控制

目的 贮液缸内液位的变化对啤酒灌装机的正常工作以及产品质量和生产效率等有重要影响，传统的PID控制很难准确控制贮液缸内的液位，为提高啤酒灌装机的工作效率和啤酒的质量等，需对贮液缸内液位进行精准控制。方法 根据分数阶微积分理论的知识，提出分数阶PID控制，该控制方法将传统的PID控制推广到分数阶领域中，利用Oustaloup算法实现传统PID控制由点到面的转变，使控制精度更高。针对分数阶PID控制器参数的调整问题，结合智能控制理论，引入模糊控制算法，提出模糊分数阶PID控制，以实现参数的在线调整，并与传统控制方法进行对比。结果 利用Simulink工具箱搭建模糊分数阶PID控制的啤酒灌装机贮液缸内液位控制系统的仿真平台，与传统控制相比较，模糊分数阶PID控制器能够获得良好的控制性能指标，无论动态指标还是静态指标以及抗干扰能力，都有较大的改善。结论 采用文中提出的方法能够明显提高液缸内液位的精准控制精度，提高啤酒灌装机的工作效率以及啤酒的质量，满足了工业生产的要求。

Liquid Level Control in Storage Cylinder of Beer Filling Machine Based on Fuzzy Fractional PID

In view of the close relationship between the change of liquid level in the tank and the normal operation of beer filling machine, the quality and efficiency of beer production, traditional PID control will be difficult to accurately control the liquid level in the tank. In order to improve the working efficiency of beer filling machine and the quality of beer, precise control of liquid level in the tank is needed. According to the knowledge of fractional calculus theory, a fractional order PID control was proposed. This control extended the traditional PID control to the fractional order domain. The Oustaloup algorithm was used to realize the transformation of the traditional PID control from point to surface to obtain higher control accuracy. To adjust parameters of the fractional order PID controller, a fuzzy fractional order PID controller was proposed by introducing the fuzzy control algorithm in combination with the intelligent control theory, to realize online adjustment of parameters and compare with the traditional control. Simulink toolbox was used to build the simulation platform of the level control system in the tank of beer filling machine controlled by fuzzy fractional PID. Compared with the traditional control, the fuzzy fractional PID controller can obtain good control performance indicators. Both dynamic and static indicators as well as anti-jamming ability were greatly improved. The method presented in this paper can obviously improve the control precision of liquid level in the cylinder, improve the efficiency of beer filling machine and quality of beer, and meet the requirements of industrial production.