【作者】 毕崇宁；

【导师】 李歧强；

【作者基本信息】 山东大学 ， 控制理论与控制工程， 2008， 硕士

【摘要】 我国是世界的电力大国,据报道,截止到2003年一月我国电力装机容量为3.53亿千瓦,发电量是1.64万亿千瓦时,均居世界第二位,仅次于美国。这其中建筑耗能约占到四分之一左右,尤以大型商业建筑为最。所谓的建筑能耗,实际上并不是直接消耗在建筑上,而是大部分直接消耗在暖通空调(HVAC)系统上。建筑节能的主要措施包括改进围护结构的性能:改进系统(如暖通空调系统)形式、运行管理方式等。虽前者在建筑节能中起主要作用,但后者的影响也不容忽视。因此,有必要对暖通空调系统进行节能优化研究。暖通空调系统是非线性、多变量、大滞后系统。它的运行普遍存在“两低一高”的现象,即冷热源和循环水泵负荷率低,系统运行效率低,能耗高。为解决该问题,本文在确定设备运行的高效区基础上,建立其效率优化模型并给出效率优化策略。而变频技术的日益成熟为空调变流量运行提供了一种切实可行的节能方案,从而使得变水量(VWV)空调系统越来越受欢迎,广泛应用于各类建筑中,为人们的工作、生活带来舒适,也满足了某些产业对生产条件的苛刻要求。迄今为止,诸多学者开展了变水量空调系统的优化研究,但就其采用变频训速泵进行水量调节的问题而言,还多停留在对变频驱动存在问题的归纳、探讨以及节能问题的定性分析或实验测量上,而就其冷水机组的优化问题而言,最优冷水机组负荷的分配问题是目前研究的热点。本文结合暖通空调水系统各用电设备的运行特点及一些实际要求,对涉及暖通空调水系统效率优化策略研究的建模方法、求解方法和控制策略等方面的问题进行了大量的理论和仿真研究。主要研究工作如下:首先,总结暖通空调系统负荷的计算方法并加以比较,对比各种空调负荷计算软件的优缺点,针对某建筑实例采用EnergyPlus建筑能耗评估软件仿真空调负荷在一天中的逐时变化情况,为空调设备选型及优化策略研究提供基础。其次,将变频调速技术应用在变水量二次泵暖通空调系统中,测量二次泵额定转速下流量-扬程数据及流量-功率数据,应用最小二乘法拟合这些数据,得到流量-扬程关系式及流量-功率关系式。分析确定二次泵运行的高效区,作为其效率优化建模的约束条件,建立二次泵效率优化模型。再次,测量冷水机组运行性能系数(COP)与其部分负荷率(PLR)之间的对应关系,经数据拟合得到性能系数与部分负荷率的关系式。为使机组高效运行,即保证多台冷水机组整体的性能系数最优,建立冷水机组效率优化模型。最后,求解二次泵效率优化模型及冷水机组效率优化模型,得到二次泵效率优化策略和冷水机组效率优化策略,并给出该策略下对应设备的能耗情况,分析其节能效果。文章最后对全文进行了总结,指出了本文研究的优缺点,并提出了有待进一步研究的问题。更多还原

【Abstract】 It was reported that Chinese generation capacity reached 1.64 trillion kwh in January, 2003 and ranked second after the United States in the world. Building consumes much energy, which accounts for about a quarter, particularly for the large commercial building. The so-called building energy consumption primarily consumes in the HVAC (Heating, Ventilating and Air Conditioning) system. Improving the performance of envelope structure is the most effective strategies for building energy conservation. But improving HVAC system’s configuration, management and operation mode plays an important role in the building energy conservation. Therefore, it is necessary to carry out HVAC system’s optimization research for energy saving.HVAC system is a non-linear, multi-variable and big delay system. Its operation has a problem of "two low and one high" problem, that is to say cooling/heating source and the circulating pump have low rate of load, the system’s operation efficiency is low but the energy consumption is high. To solve the problem, the author brings the equipment’s high efficient operation into its optimization modeling and establishes the equipment’s efficiency optimization model and then gives the efficiency optimization strategies. Variable frequency technology is increasingly mature, so variable flow for the air-conditioning is widely installed in all kinds of buildings. It makes people feel more comfort during working and living. It also meets the harsh production conditions of some industry. So far, many scholars studied the optimization of VWV (Variable Water Volume) air conditioning system. For pumps with VSD (Variable Speed Drive), the research is primarily about the discussion of VSD problem or qualitative analysis and experimental measurement on energy saving. And for the chiller’s optimization problem, the optimal chiller load distribution is a hot research at present.The paper carried out a large number of theoretical and simulation research about the methods of modeling, solving and controlling strategies for the research of HVAC system efficiency optimization strategies. The research was achieved by analyzing the operational features and practical requirements of electricity equipment in water plant loop of HVAC system. Main researches are as follows.First, summarize and compare the load calculation method of HVAC system. The simulation with EnergyPlus was done for some building after contrasting various air conditioning load calculation software. The simulation results showed the real-time changes of air-conditioning load during one day. This will provide the basis for air-conditioning equipment selection and the research of optimization strategies.Second, apply VSD technique for primary-secondary pump then measure some datas of Flux-Head and Flux-Power when the pumps operate under the rated speed. These datas were curve fitted by applying the least square method. And the relationships of Flux-Head and Flux-Power were given. The high efficiency field of secondary pump was regarded as the constraint of its efficiency optimization model. The secondary pumps’ efficiency optimization model was established in the paper.Third, analyze the relationship between the chiller’s COP (Coefficient of Performance) and the PLR (Part Load Ratio). And the relationship was given by curve fitting. In order to make multiple chiller’s overall COP value be optimal, that is, the operation of chillers is high efficient, the chillers’ efficiency optimization model was established.Finally, solve the secondary pumps’ efficiency optimization model and the chillers’ efficiency optimization model. Then the secondary pumps’ efficiency optimization strategies and the chillers’ efficiency optimization strategies were given and the equipments’ energy consumption was also given with these strategies. The effects of their energy saving are obvious.The article ended with a summary of the full text, pointed out the advantages and disadvantages of this paper, and put forward the issues which need solving in the future.更多还原