超市制冷系统解同步控制研究

发布时间：2018-09-14 20:09

【摘要】：在建设节约型社会的今天,如何提高设备利用率,延长设备使用寿命已成为一个越来越重要的议题。超市制冷系统承担了大部分冷链的终端零售任务,分布广泛,数量众多。超市制冷系统主要由压缩机组、冷凝器单元和多个相互独立的陈列柜组成。各个陈列柜中的温度控制器通常采用滞环控制。在实际工作中人们发现,这些滞环控制操作容易趋于一致,导致系统吸气压力在大范围内波动,相应的阀门、压缩机组频繁切换,这就是同步现象。同步现象产生后不仅增加了压缩机组的负载,降低了其使用寿命,而且会使系统能耗增加。因此在保证食品存储质量的基础上,解决系统同步的问题,在延长制冷系统使用寿命以及提高能源利用率等方面都有着积极的意义。本文主要内容如下：首先,本文介绍了一般制冷系统的制冷原理；并从超市制冷系统的结构入手,用数学模型描述了各个部件,如陈列柜,蒸发器等；在此基础上,阐述了一般制冷系统simulink模型的建立方法,搭建了超市制冷系统仿真平台,其中包括GUI交互界面,超市制冷系统的模型以及相应的性能评价指标。性能评价指标分别衡量了存储质量、压缩机使用寿命和压缩机能耗三个方面。另外,该仿真平台可以根据需要调整陈列柜和压缩机的个数,可以扩展到大型制冷系统中。其次,为了验证系统在同步前后相应的性能指标的变化,本文在建立起来的仿真平台中应用了两种低复杂度解同步算法,以小型制冷系统为例,通过系统仿真,证明了系统在解同步后的工况要好于系统同步时的工况。在此基础上,把这两种方法扩展到大型的制冷系统中去,结果表明这两种方法对大型制冷系统解同步也是有效的,验证了这两种方法的解同步能力。最后,本文在对整个制冷系统进行分析后,通过总结前人的研究,用分岔分析证明了制冷系统的环境负载是影响系统陈列柜温度变化的重要因素；利用搭建的仿真平台,验证了其改善系统性能指标的有效性；在大型制冷系统模型中的仿真,同样也证明了该方法对大型制冷系统解同步有效性。
[Abstract]:How to improve the utilization rate of equipment and prolong the service life of equipment has become an increasingly important issue in the construction of a conservation-oriented society. Supermarket Refrigeration system undertakes most of the retail tasks of cold chain terminals, widely distributed and numerous in quantity. Supermarket refrigeration system is mainly composed of compressor unit, condenser unit and several independent display cabinets. The temperature controller in each display cabinet usually adopts hysteresis control. In practice, it is found that these hysteretic control operations tend to be consistent, resulting in the system suction pressure fluctuating in a wide range, the corresponding valves and compressor units switching frequently, this is the synchronization phenomenon. The synchronous phenomenon not only increases the load of the compressor unit and reduces its service life, but also increases the energy consumption of the system. Therefore, on the basis of ensuring the quality of food storage, solving the problem of system synchronization is of positive significance in prolonging the service life of refrigeration system and improving energy utilization efficiency. The main contents of this paper are as follows: firstly, this paper introduces the refrigeration principle of the general refrigeration system, and starts with the structure of the refrigeration system in the supermarket, describes each component with mathematical model, such as display cabinets, evaporators, etc. The method of establishing simulink model of general refrigeration system is introduced, and the simulation platform of supermarket refrigeration system is built, which includes the interactive interface of GUI, the model of supermarket refrigeration system and the corresponding performance evaluation index. Performance evaluation measures storage quality, compressor service life and compressor energy consumption. In addition, the simulation platform can adjust the number of display cabinets and compressors according to the need, and can be extended to large-scale refrigeration system. Secondly, in order to verify the change of the corresponding performance index before and after synchronization, two low complexity desynchronization algorithms are applied in the simulation platform. It is proved that the working condition of the system after desynchronization is better than that when the system synchronizes. On this basis, the two methods are extended to the large-scale refrigeration system. The results show that the two methods are also effective for the desynchronization of the large-scale refrigeration system, and verify the ability of the two methods to de-synchronize. Finally, after analyzing the whole refrigeration system, through summarizing the previous research, the paper proves that the environmental load of the refrigeration system is an important factor affecting the temperature change of the display cabinet, and the simulation platform is built. The effectiveness of the improved system performance index is verified, and the simulation in the large-scale refrigeration system model also proves the effectiveness of the method for large-scale refrigeration system desynchronization.
【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TB657;TP273

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