基于动态负荷跟踪的中央空调系统全闭环节能技术的研究

本文力图从中央空调系统的运行模式上探讨能耗高的成因,研究解决该问题的关键技术。为此,研制出一个基于动态负荷变化,主机随动跟踪调节,辅机采用变频调速技术构成全闭环的中央空调控制系统。寻求最优的控制规律,使中央空调主机、冷媒流量系统都随负荷的变化而变化,旨在满足空调区舒适性所需负荷前提下,实现系统最大限度的节能。     

智能模糊控制技术用于中央空调控制

本文主要介绍了利用智能模糊控制技术,以系统集成技术和现代变频技术为手段,实现中央空调系统运行参数的实时调整,实现冷媒流量跟随负荷的变化而变化,从而确保主机在任何负荷条件下都处于最佳工况,始终保持较高的转换效率。1系统的构成(见图1)中央空调系统负荷的变化会导致系统     

典型户型空调系统设计及分析

通过对寒冷地区、夏热冬冷地区和夏热冬暖地区同一典型户型住宅在节能热工设计标准条件下空调负荷的计算,得出住宅建筑的冷热负荷指标;主机容量确定和末端装置选择方法;对比分析发现,采用变频技术控制主机压缩机和风机可获得显著的节能效果;采用变频技术以及计算机控制技术的小型变风量系统尤为适合风管型户式中央空调系统;水管型户式中央空调系统则较适宜采用末端风机盘管的风量调节和主机变频调节相结合的调节方式.     

家用中央空调系统型式及关键点的控制

介绍了目前家用中央空调系统的型式及主要产品的特点。对家用中央空调的冷热负荷进行了讨论，提出了家用中央空调的能耗指标、噪声等系统关键点的控制措施。     

一种简化中小型空调水系统控制设备的方法

<正> 中央空调的冷冻水系统,起着冷量输送与分配的作用,对其运行状况正确可靠地进行控制调节,是一个空调系统满足设计要求的前提。我国现有的大、中型空调冷冻水系统,普遍采用主机侧定流量,负荷侧变流量的控制方法。具体做法是在冷冻机房分水缸和     

冰蓄冷系统中主机制冷量的确定

通过对三种不同配置的冰蓄冷系统的逐时负荷和各节点载冷剂温度变化的详细分析,指出根据目前常用的公式计算出的主机制冷量在很多场合不能满足实际负荷要求。通过对这几种系统控制性能的初步比较得出主机上游且融冰优先的串联系统最有效,同时指出配有基载主机的蓄冰系统的负荷分配设计中需要注意的问题。     

基于负荷预测的空调冷冻水流量动态控制技术

本文通过对现有的中央空调冷冻水系统变流量控制技术局限性的分析，提出了基于负荷预测的冷冻水流量动态控制理念，并较详细地介绍了负荷预测控制的基本思想和控制原理，为中央空调冷冻水系统变流量节能控制提供了一种全新的控制技术。     

"合同能源管理"系列之三智能模糊控制技术高效控制中央空调

随着我国房地产业的蓬勃发展,中央空调行业也得到飞速的发展。据预测,2005年中国中央空调市场需求总量达到250亿元人民币,2010年将达到400亿元人民币。然而,中央空调安装量的不断增加,使得空调用电负荷占了电力总负荷的20%以上,成为我国建筑物中最大的用电设施。长期以来,由于缺乏先进的中央空调控制与管理技术装备,中央空调系统一直沿用着传统的开关控制方式,不能实现空调冷媒流量跟随末端负荷的变化而动态调节,在部分负荷运行时经常发生大流量小温差现象,造成能源浪费很大,使中央空调的节能成为建筑节能中的一个重要课题。本文介绍了一种…     

双碳背景下冰蓄冷空调系统在福州某城市综合体中的应用研究

为响应国家减排政策，平衡电网负荷，结合福州市的峰谷电价政策，通过对福州市某城市综合体的冷负荷分布情况进行分析，对常规中央空调系统与冰蓄冷中央空调系统的经济性进行对比，确定项目采用冰蓄冷空调系统的可行性，进而分析探讨该项目冰蓄冷设计的特点，以期为类似工程提供参考。     

中央空调系统安装工程技术措施探讨

中央空调系统是一个较复杂的系统,它采用的是集中处理空调负荷的形式,因此,相对于分散处理空调负荷的分散式空调系统而言,中央空调系统具有能效高、集中控制、方便管理等特点。本文重点探讨中央空调系统安装工程中几种常见技术措施。     

家用中央空调系统节能分析

对家用中央空调系统进行了介绍,分析了影响家用中央空调系统能源消耗的关键因素,从室内热环境、建筑物围护结构、空调设备选择、空调系统形式、空调设计等方面提出了家用中央空调系统的节能方案,以达到节约能源的目的.     

中央空调系统整体能效分析方法的研究

提出用空调系统的整体能效比来评价空调系统的实际运行效率与能耗,并给出了空调系统整体能效比的理论计算方法,以更好地反映空调机组在实际运行中的能源利用效率,该方法对分析空调系统全年能耗具有一定的参考价值。     

室内温、湿度对人体热舒适和空调能耗影响的研究

以采用一次回风集中空调系统的办公建筑为例,就室内温、湿度设计参数对空调房间热舒适环境和空调系统能耗的影响进行了分析。研究结果表明,在同样的室内人体热舒适环境(等效温度)的条件下,随着室内温度的增加,一次回风系统的需冷量和总的耗能量是增加的。因此,夏季提高空调室内温度是不节能的。在相同热舒适(等效温度)条件下,要减少空调系统的冷负荷,室内设计温、湿度参数在推荐的热舒适区范围内,宜采用较大的室内相对湿度和较低的室内干球温度的组合,或采用较高的等效温度。     

The effect of heat-pipe air-handling coil on energy consumption in central air-conditioning system

A study was carried out to investigate the effect of heat-pipe air-handling coil on energy consumption in a central air-conditioning system with return air. Taking an office building as an example, the study shows that compared with conventional central air-conditioning system with return air, the heat-pipe air-conditioning system can save cooling and reheating energy. In the usual range of 22–26 °C indoor design temperature and 50% relative humidity, the RES (rate of energy saving) in this office building investigated is 23.5–25.7% for cooling load and 38.1–40.9% for total energy consumption. The RES of the heat-pipe air-conditioning system increases with the increase of indoor design temperature and the decrease of indoor relative humidity. The influence of indoor relative humidity on RES is much greater than the influence of the indoor design temperature. The study indicates that a central air-conditioning system can significantly reduce its energy consumption and improve both the indoor thermal comfort and air quality when a heat-pipe air-handling coil is employed in the air-conditioning process.     

Part load operation coefficient of air-conditioning system of public building

IPLV overall coefficient, presented by Air-Conditioning and Refrigeration Institute (ARI) of America, shows running/operation status of air-conditioning system host only. For overall operation coefficient, logical solution has not been developed, to reflect the whole air-conditioning system under part load. In this research undertaking, the running time proportions of air-conditioning systems under part load have been obtained through analysis on energy consumption data during practical operation in all public buildings in Chongqing. This was achieved by using analysis methods, based on the statistical energy consumption data distribution of public buildings month-by-month. Comparing with the weight number of IPLV, part load operation coefficient of air-conditioning system, based on this research, does not only show the status of system refrigerating host, but also reflects and calculate energy efficiency of the whole air-conditioning system. The coefficient results from the processing and analyzing of practical running data, shows the practical running status of area and building type (actual and objective) - not clear. The method is different from model analysis which gets IPLV weight number, in the sense that this method of coefficient results in both four equal proportions and also part load operation coefficient of air-conditioning system under any load rate as necessary.     

室内空气设计参数与空调系统节能条件浅析

本文针对暖通空调系统设计过程中室内空气参数标准的合理取值对空调能耗的影响,探讨了空调负荷、空调能耗和空调系统节能的基本概念,对室内空气温度和相对湿度标准对空调系统能耗的影响进行了计算分析,结果表明科学认识室内空气参数标准的合理取值对空调系统能耗的影响对当前建筑节能意义重大;空调系统节能条件需要具体分析,针对不同类型的建筑和不同的空调方式,其室内空气设计标准的影响不同,空调过程设计对空调系统节能具有重要影响。另外,将典型空调案例的计算结果推广到一般工程,容易导致工程设计概念上的混淆。     

Global optimization of a central air-conditioning system using decomposition-coordination method

The global optimization model for the overall control of air-conditioning system aiming at the minimum energy consumption is developed in this work. The method of decomposition-coordination, which is adept at solving the ultrahigh-dimensional optimization problems, is used for the model solution. Taking one real central air-conditioning system as the case study, the hourly optimal conditions of all equipments in this system on one operation day were simulated by the global optimization model. To examine the validity of decomposition-coordination algorithm, direct-search method (which is admitted to be the most reliable in optimization calculation) is used to make the comparison. It showed that the optimal results obtained by the two methods were essentially the same, but decomposition-coordination method would have much higher calculation efficiency than direct-search method. The energy analysis indicated that the energy saving brought by the global optimization was mainly thanks to the adjustment of pumps and fans rather than that of the chillers. It was believed as well that more energy saving would be achieved under the lower load condition of the system if the globally optimal control scheme were implemented.     

A new method of determination of indoor temperature and relative humidity with consideration of human thermal comfort

A new method is described in this article for selecting indoor temperature and indoor relative humidity to achieve minimum energy consumption for a required indoor thermal comfort level which is evaluated with indoor effective temperature. This method is derived from a central air-conditioning system and is based on our investigation that under a same indoor effective temperature, the system cooling load and the system energy consumption increase with an increase of indoor temperature. As such, energy consumption cannot be reduced with increasing indoor temperature for a given human thermal comfort level. In order to reduce energy consumption while keeping a same indoor thermal comfort level, indoor temperature and relative humidity may be determined with the proposed method described in this article. With the proposed method, a parameter variation study has also been conducted, which suggests that for a given indoor effective temperature, a combination of high indoor relative humidity and low indoor temperature be generally taken. The proposed method is based on the central air-conditioning system; yet it can be easily extended to other systems.