摘要
针对制冷系统大时滞、强耦合的特性,在辨识得到并通过实验验证的压缩式制冷系统双输入双输出模型基础上,应用恒定蒸发温度与变最小过热度结合的双闭环控制方案,设计了基于逆向解耦环节的内模控制方法,仿真实验结果表明,与常规PID控制方法相比可明显增强系统稳定性,减小调节时间。与传统内模解耦方法相比,控制器设计简单,便于实现。考虑到在变负荷下制冷系统内部参数会时常产生较严重的摄动,辨识模型可能存在未建模的不确定因素,将模型参数按一定比例变动,仿真结果表明在模型参数摄动时仍具有良好的控制效果。
Refrigeration system is a system with large delay,strong coupling and other characteristics.In this paper,an internal modelling control method with an inverted decoupling link is designed basing on the two inputs and two outputs model of compressive refrigeration which is obtained through identification and is verified through experiment.A double closedloop control scheme combining constant evaporation temperature and variable minimum superheat temperature is applied.Result of a group of simulation comparison experiment shows that compared with traditional PID control method,method in this paper can obviously enhance the system stability,reduce the adjusting time.Furthermore,it is easy to design and implement the controller compared with other complex control method.Considering that refrigeration system under variable load may result in serious inter nal parameter perturbation,and identification model may have possible uncertainties failed to model,model parameters are changed according to certain proportion.Simulation results show that method in this paper can still gain favourite control effect when the model parameters are not accurate.
出处
《中国仪器仪表》
2019年第4期47-52,共6页
China Instrumentation
基金
国家质量基础的共性技术研究与应用NQI专项
项目编号:2016YFF0202002
关键词
制冷系统
纯滞后
解耦环节
内模控制
稳定性
Refrigeration system
Time delay
Decoupling link
Internal model control
Stability
