冷水机组季节性能评价新指标SPLV和IPLV的比较

基于"性能指标应等于季节总制冷量与总耗电量之比"的物理意义提出了季节部分负荷性能系数SPLV新指标。就SPLV和IPLV的公式形式、指标大小以及在典型性能曲线中的应用三个方面对二者的区别与联系进行分析,得出结论:SPLV与IPLV采用相同的构成要素,但二者的公式形式和量纲不同;对同一机组而言,IPLV≥SPLV,且各部分负荷工况点的性能系数COPc差别越大,其IPLV相对SPLV偏差也越大。     

磁悬浮离心式冷水机组和国家标准北大核心

磁悬浮离心式冷水机组已在国内外诸多空调工程中应用,因其性能系数高,大大降低了冷水机组的全年能耗。分析了该类型冷水机组在国内的应用现状,指出作为一种冷水机组产品,应执行现有的相关国家标准,同时应参考国外标准;建议深入理解国内外标准中名义工况下的COP、综合部分负荷性能系数IPLV和非标准工况下综合部分负荷性能系数NPLV,正确评价磁悬浮离心式冷水机组的性能。工程实例计算结果表明,磁悬浮离心式冷水机组与普通离心式冷水机组相比,全年可减少能耗40%左右,其名义工况下的COP达到国家冷水机组1级能效等级,其IPLV超过8.7。认为其独有的特性将改变部分空调系统的传统设计方法,值得深入研究,磁悬浮离心式冷水机组是一种值得大力推广的高效节能产品。     

计算部分负荷性能参数正确选择冷水机组

推导出了计算空调季节总能耗，总制冷量，季节能耗指标及季节能效比的简单公式，算出了评价各种冷水机组在整个空调季节运行综合性能的参数－部分负荷性能综合值，阐述了从能耗角度选择冷水机组的原则。     

联合运行冷水机组负荷优化分配及仿真研究

根据冷水机组的性能系数与其部分负荷率相关的特性,提出一种基于最小能耗的联合运行冷水机组负荷优化分配方法,从而获得最佳的机组负荷分配率和性能系数。对该负荷优化分配方法进行了MATLAB仿真。仿真结果表明,该控制策略能够优化机组的运行,减少系统能耗。     

冷水机组综合部分负荷性能指标与能耗计算

探讨了ARI标准550／590-2003中综合部分负荷性能系数的含义及其与季节能效比的关系,认为季节能效比能更全面地反映冷水机组的季节或全年平均能源利用效率。给出了一个简单实用的全年能耗计算公式和一个基于全年能耗的部分负荷性能指标。     

广州地铁车站冷水机组NPLV研究与实践

GB 19577—2015《冷水机组能效限定值及能效等级》中IPLV所反映的冷负荷分布、权重系数和平均冷却水进水温度与地铁工程差异较大,这种差异与地区密切相关。基于地铁车站运营数据,提出了广州地铁非标工况下综合部分负荷性能系数NPLV的计算公式;对比分析了近、远期NPLV的不同;初步探讨了NPLV对制冷主机选型的参考价值。     

基于液体载冷剂法的空调器性能测量不确定度分析

基于液体载冷剂法，应用间接测量参数的不确定度理论，建立了空调器性能参数的标准不确定度计算模型，给出了基于液体载冷剂法性能测量参数的标准不确定度评价方法。以水冷冷水机组综合部分负荷性能系数的标准不确定度评定为例进行分析。结果表明：进出水温度测量引入的标准不确定度对水冷冷水机组的综合部分负荷性能系数影响较大，其次是水流量和功率测量因素；综合部分负荷性能系数的A类标准不确定度远小于B类标准不确定度。因此，在测量水冷冷水机组综合部分负荷性能时，需要重点关注仪器仪表的精度，较高的仪器仪表精度能有效降低水冷冷水机组性能参数的测量不确定度。     

现行国标中冷水机组IPLV定义式的错误剖析

在分析GB/T18430.11-2007、GB50189-2005以及相关研究文献的基础上,指出我国关于冷水机组综合部分负荷性能系数IPLV的定义无论是表达形式还是其4个权重系数都是错误的。以现有文献资料数据为案例,给出了正确构建IPLV表达式的方法。     

基于AHRI新能效标准下的空调机组性能测试及研究

美国标准ANSI/AHRI Standard 340/360-2007使用IEER(Integrated Energy Efficiency Ratio,综合能效比)来替代IPLV(Integrated Part Load Value,综合部分负荷性能系数)作为工业和商业用单元式空调及热泵设备的性能评价指标。在焓差性能实验室里对单元式空调机组进行满负荷以及其他部分负荷下的性能测试。计算出机组综合能效比IEER,并从不同的方面比较IEER评价方法与IPLV评价方法所存在的区别,分析了美国使用IEER替代IPLV作为工业商业用单元式空调机及热泵设备的性能评价指标的动机及意义。经对比得出使用IEER评价方法可以更科学地评价机组性能,对能源的可持续发展可产生良好效应。     

多联式空调系统全年运行性能评价

本文提出了评价多联式空调系统的季节性能和全年运行性能指标及其计算式、计权系数和测试工况点参数的确定方法,并验证了其正确性。结果表明,将基于建筑逐时负荷特性和区域平均划分法的8区域法用于评价数码涡旋多联式空调系统的季节性能和全年运行性能,既能保证计算精度又简单易行;由于多联式空调系统部分负荷特性的相似性,该评价方法既适用于评价1拖n数码涡旋或变频控制多联式空调系统实际运行性能,也适用于评价整栋建筑多联式空调系统全年运行能耗和全年综合能源使用效率,进行初步设计阶段不同空调系统方案的节能性比较。     

正确理解、解释与应用ARI 550/590标准中的IPLV指标

概述了美国ARI 550/590标准的历史演变及两次修订的主要内容。给出了综合部分负荷值IPLV与非标准部分负荷值的定义,详细分析了目前国内对IPLV指标的理解、解释和应用的分歧点,并引用该标准的相关条文与白皮书的内容,阐明作者的观点。     

采用单压缩机与双压缩机的多联式空调机组的性能比较

实验比较了单压缩机和双压缩机多联式空调机组的能效比和综合部分负荷性能系数,结果表明,采用定速压缩机和变频压缩机并联的双压缩机空调机组的平均能效比为3.6W/W,综合部分负荷性能系数为3.67;而单压缩机空调机组的平均能效比和综合部分负荷性能系数分别为3.1W/W和3.21;双压缩机空调机组有较好的节能效果。     

Energy signatures for assessing the energy performance of chillers

This paper investigates how energy signatures can be used as an alternative to an energy use intensity (describing the annual electricity consumption of chillers in kWh per unit floor area of a building in m²) to assess the energy performance of chillers with various design options and operating strategies. An energy signature is a best-fit straight line relating chiller power to a climatic index when chillers operate for a building cooling load profile. Sixteen combinations of four design options and four operating strategies for chillers serving a hypothetical hotel are studied by simulation. For each combination, an energy signature for the chillers is determined. The slope and intercept of the energy signature can be used to accurately predict the annual electricity consumption of the chillers and to evaluate the extent to which this consumption can drop when chiller efficiency is improved. It is desirable to develop reference energy signatures in relation to different characteristics of building cooling load as a yardstick for the minimum requirement of chiller performance. With this yardstick, the effectiveness of energy efficient measures in the operation of chillers could be identified.     

Experimental study of performance of digital variable multiple air conditioning system under part load conditions

An experimental study on performance of digital variable multiple air conditioning system under part load conditions in hot summer and cold winter zone was conducted in this paper. The effects of outdoor air temperature and on-unit ratio on total power consumption in 1 h, hourly heating performance factor or hourly energy efficiency ratio were analyzed by experiments. The variations of hourly heating performance factor (or hourly energy efficiency ratio) and total power consumption in 1 h with part load value under different outdoor air temperature were obtained. The results indicate that digital variable multiple air conditioning system can keep economical and reliable operation under part load conditions. And it is necessary to study the index which may reflect the seasonal energy consumption of digital variable multiple air conditioning system.     

Optimum load sharing strategy for multiple-chiller systems serving air-conditioned buildings

Many central cooling systems in air-conditioned buildings have multiple chillers to meet various cooling load requirements. This paper further develops optimum load sharing strategies for the chillers in order to maximize their aggregate coefficient of performance (COP). Based on the part load performance curves of air-cooled screw chillers, it is ascertained that for two equally sized chillers operating, one should carry a full load and the other should be partially loaded to meet the system load. When two chillers of different sizes are running, the larger chiller should be fully loaded and the smaller chiller should operate at part load in order that their combined capacity satisfies the system load. Such an uneven load sharing strategy for achieving maximum COP is independent of ambient conditions and the control of condensing temperature. The variable primary flow of chilled water should be applied to chillers in order to implement the strategy. The results of this paper are useful in developing low-energy chiller plants.     

冷水机组节能驱动与控制系统的选择与计算（二）

本文提出一种在工程设计中能快速列表计算、具有几种不同节能驱动与控制系统的冷水机组的综合部分负荷性能系数LPLV的方法。这些部基于LPLV的标准公式和它们的特性曲线族图表。比较它们的IPLV的计算结果的大小,即能选择高效驱动节能控制系统。     

冷水机组节能驱动与控制系统的选择与计算（三）

本文提出一种在工程设计中能快速列表计算、具有几种不同节能驱动与控制系统的冷水机组的综合部分负荷性能系数LPLV的方法。这些部基于LPLV的标准公式和它们的特性曲线族图表。比较它们的IPLV的计算结果的大小,即能选择高效驱动节能控制系统。关键词冷水机组ARI标准国家标准综合部分负荷性能系数性能系数能效比能耗比驱动特性曲线族图表变频驱动恒速驱动节能驱动与控制系统     

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.     

多联机的三种制冷季节性能评价指标的差异性分析

对一台多联机进行了35个工况的制冷性能试验,获得了该多联机的全工况制冷运行性能。应用GB/T 17758—2010《单元式空气调节机》规定的建筑冷负荷模型、制冷运行时间模型和实测多联机性能值,分别采用中国、日本、美国三种现行评价体系对被测多联机的制冷季节运行性能进行计算,并与其全工况季节运行性能指标进行对比,指出各评价指标的差异性。