针对压缩制冷机组的温度控制问题,在分析机组机理的基础上,基于现有实验平台,采用改进的分区集中参数法,结合机理建模与实验辨识,提出制冷机组合理简化后的模型,并通过仿真与实验曲线对比,验证模型的准确性;设计蒸发器子系统的扰动观测器,证明扰动估计误差的有界性,并将扰动及其导数的估计值引入滑模面设计中;提出一种非奇异terminal滑模面,将二阶滑模与terminal滑模相结合,设计控制率,最后与传统滑模法进行仿真对比.研究结果表明:提出的控制方法对扰动具有良好的动态性能,同时消除了抖振.%Considering the temperature control issue in refrigeration system, and based on the analysis of the mechanism of compression refrigeration system, a reasonable simplified model was proposed by improving zone lumped parameter method. Besides, mechanism modeling and experimental identification based on the experimental platform were combined together. The model was proved to be accurate through the simulation and experiment. A disturbance observer of evaporator was proposed, and then its error was proved to be bounded. The estimated value of disturbance and its derivative were used to design the sliding mode surface; the second-order sliding mode was combined with terminal sliding mode which was proved to be non-singular, and then the controlled variable was designed. The simulation results were compared with those of traditional method. The results show that the proposed method has better dynamic performance against disturbance and can eliminate chattering problem compared to traditional sliding mode control.
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