【作者】 林建泉；

【导师】 舒朝晖；

【作者基本信息】 华中科技大学 ， 制冷及低温工程， 2009， 硕士

【摘要】 冰蓄冷技术不仅可以移峰填谷、平衡电网,而且还可以利用峰谷电价差节省运行费用,目前已成为我国积极推广的一项实用节能技术。目前关于小型冰蓄冷空调方面的研究绝大部分还是局限于系统特性和实验方面,对于运行控制策略方面,可借鉴的资料很少,而运行控制策略的选择是否合理直接关系到整个系统的经济性及可行性,因此,有必要对小型冰蓄冷系统的运行优化控制策略进行探讨。首先对小型过冷式冰蓄冷多联空调系统的工作原理进行阐述,并针对不同的蒸发温度、冷凝温度和过冷度,采用EES软件对系统的单位制冷量、性能系数以及有效能效率进行模拟计算,分析系统在夏季运行时的循环特性。其次结合该系统的运行特点,提出基于BP神经网络负荷预测的优化控制方案,综合考虑室外环境温度、部分负荷率、系统循环特性以及蓄冰槽的传热性能等因素的影响建立系统的优化控制数学模型,引入动态规划逆序解法对该模型的最优化问题进行求解,同时基于优化控制在实际应用中的复杂性,提出一种简单有效的近优化控制策略—逐步逻辑判断优化法。最后通过一个实例对比分析优化控制、逐步逻辑判断优化以及主机优先三种控制策略下系统的经济性。通过实例计算得出,优化控制较常规空调系统节省运行费用14.2%,逐步逻辑判断优化较常规空调系统节省运行费用13.9%,主机优先较常规空调系统节省运行费用10.5%。本文研究成果,为今后小型冰蓄冷空调系统的实际应用和改造提供理论依据和指导作用,同时也对小型冰蓄冷空调系统的推广工作起到一定的促进作用。更多还原

【Abstract】 Ice storage air conditioning system has become a widely used technology for saving energies with the advantage of it in avoiding high demand during on-peak and reducing the operating cost cooling equipment. Most of the researchers focused on the experiments. Choosing a better operational control is directly related to the economic feasibility of the whole system. But there are few references about the studies of optimal control methods. So, it is necessary to discuss the operational control in the Mini-type multi-units with sub-cooled ice storage system.Based on the discussion of the working principle of Mini-type multi-units with sub-cooled ice storage system, we used EES package to simulate the refrigerating capacity per weighing, COP and energy efficiency under different conditions such as evaporating temperature, condensing temperature and degree of supercooling. The simulation results were carried out to analysis the cycle characteristic of systems operating in summer.We developed an effective method to predict the operation control on the basis of BP ArtificialNeuralNetworks (ANNs). The model was set up by the factors of outdoor ambient temperature, load rate, cycle specificity and temperature conductivity of ice-tanks. The optimization of model was solved by dynamic programming. Moreover, a simply and effective optimization control method was proposed---stepwise logical judgment optimization method.Finally, results were used to analysis the system economy under optimization control method, stepwise logical judgment optimization method and chiller-priority. The optimization calculation show that optimal control can save 14.2% expense, logical judgment can save 13.9% expense and chiller-priority can save 10.5% expense than normal air-conditioning system.Present work can provide a theoretical basis and guiding principles for the practical applications of Mini-type multi-units with sub-cooled ice storage system.更多还原