基于PLC的冷却系统自整定模糊控制研究

Research of the PLC Based Parameter Self-tuning Fuzzy Control for Cooling System

在机载产品地面试验过程中需要为其提供相应的冷却环境,可在受试产品发生改变时,制冷设备在传统控制算法下往往无法维持较为理想的控制结果,需要重新人工整定控制参数。为解决此问题,研究了基于PLC的冷却系统自整定模糊控制方法,该方法可在PLC内编写系统参数累加辨识程序,从而计算得到系统的模型参数以及初始控制参数,再通过模糊控制器对该参数进行实时整定。试验表明该控制方法可以对系统参数进行自动辨识,辨识结果能够反映模拟负载的功率变化趋势,控制结果无明显超调及稳态误差。将该方法应用于液冷机组,可以在被冷却对象发生较大变化时重新辨识控制器参数,免去人工进行参数调试的工序,加强了设备的通用性,获得良好的控制结果。

During the airborne products’ ground test, it needs certain thermal environment. However, when the subjects change, the cooling system sometimes cannot maintain satisfactory control result with traditional control algorithm. To solve this problem, this paper studies the PLC based parameter self-tuning fuzzy control method for cooling system. This method can calculate the system’s model parameters and controller’s initial parameters. Then the parameters are tuned by fuzzy controller in real time. Tests show that this method can automatically identify the system’s model parameters. Identification result can reflect the trends of the load. The control result has no obvious overshoot and no steady error. Applying the method into the cooling unit, it can refresh the identified parameters when the cooling object is changed and save the bother of manual tuning. It can increase the generality of the cooling unit and obtain good control results.