A fault detection technique for air-source heat pump water chiller/heaters

This paper describes a fault detection method and system to detect the faults in air-source heat pump water chiller/heaters. Principal component analysis (PCA) approach is used to extract the correlation of variables in heat pump unit and reduce the dimension of measured data. A PCA model is built to determine the thresholds of statistics and calculate square prediction errors (SPE) of new observations, which are used to check if a fault occurs in heat pump unit. The fault detection system consists of a PCA-based fault detection code, a backpack computer, a digital logger and eight easy-to-install temperature sensors. A real air-source heat pump water chiller/heater for the air-conditioning system of an office building provides the realistic test platform for the validation of fault detection method. The measured data from the heat pump unit under normal condition shows that the PCA model can capture the major correlation and variance among the test variables. Two levels of artificial condenser fouling fault are successfully detected. The results show that the PCA-based fault detection method is applicable and effective for air-source heat pump water chiller/heater.     

Analysis on performance of a novel frost-free air-source heat pump system

Heating capacity of an air-source heat pump (ASHP) system often decreases due to frost on the air-side heat exchanger (evaporator) when the air temperature drops in winter. If the amount of frost accumulates to a certain value, performance of the system will degrade. Therefore, defrosting mode needs to be operated periodically. In order to solve the above problems, heat transfer enhancement or advanced defrosting methods should be adopted, but all these methods cannot solve the problems mentioned in essence. A novel frost-free air-source heat pump system is proposed, the new system can realize heating which does not need defrost in winter. In this new system, extracting heat process from environment includes two steps: the first one is extracting heat from the environment and then to the solution, the second one is releasing heat to the evaporator from the solution, avoiding frosting on the evaporator surface. A theoretical model is established to analyze the performance of the system. Results indicate that the novel system can operate more efficiently than the conventional air-source heat pump in winter. In addition, the new system does not need to run in defrosting mode periodically.     

家用空气源热泵热水器节能分析

简要介绍了空气源热泵热水器的技术特点,并对其节能环保效益进行了分析,通过与其他形式热水器比较,指出空气源热泵热水器具有诸多优点,十分适合于家庭使用,值得大力推广。     

空气源热泵冷热水机组在寒冷地区应用的分析

针对空气源热泵冷热水机组在寒冷地区冬季使用时结霜、热效率低等问题,提出一种双级热泵系统,即由空气源热泵冷热水机组提供10-20℃温水,作为水源热泵的低位热源,组成水源热泵供热系统,分析了这种系统的技术经济性,认为该系统是可行的,具有节能和环保意义。     

浴室干燥热泵热水器实验研究

设计了一款具有除湿功能的浴室干燥热泵热水器,分析了系统结构和工作原理。对不同运行模式的实验研究表明,该热水器在节能与功能方面具有独特的优势。     

水源热泵系统在住宅供热空调中的应用

从基本原理及技术方案、经济分析等方面阐述了水源热泵系统在住宅供热空调中的应用，提出了中国水源热泵推广应用中存在的问题，对我国供热、环保和节能方面都有促进作用。     

两种工况下空气双热源热泵热水器的试验研究

对空气源热泵热水器在标准工况和低温工况下的性能进行了试验研究,并分析了进水温度对排气压力、排气温度、消耗功率、热效率的影响规律。结果表明,排气压力、排气温度和消耗功率随着进水温度的升高而增加,制热功率和性能系数随着进水温度的升高而降低;标准工况下的性能优于低温工况下的性能。     

空气源热泵热水机组在游泳池水加热中的应用

以某文体活动中心为例,从耗热量计算、空气源热泵的选型、空气源热泵的能耗计算三方面阐述了空气源热泵技术在游泳池水加热中的应用,并将其与燃油锅炉的能耗费用进行了比较,以说明空气源热泵技术的优越性。     

太阳能热水系统与地源热泵应用情况分析

对太阳能热水系统和地源热泵系统在工程实际中的应用情况进行了比较分析,分别就其工作原理、优缺点等作了论述,以期更有针对性的推广和应用这两种可再生能源系统。     

用于供暖的土壤－水热泵系统

本文介绍了无污染、低品位的土壤热源热泵实现冬季供暖的技术，提供了土壤热交换器的设计参数和室内供暖的匹配方法，并指出，与空气热源热泵的全年电费相比较，土壤热源热泵节电１０％～１２％。     

空气源热泵机组除霜技术探讨

分析了空气源热泵产品在北方地区应用受限制的原因。研究了空气源热泵产品的结霜条件、制热效率和性能系数等,提出了改进措施。研制了低环温型空气源热泵空调机组,测试数据表明,该机组在北方地区具有较好的制热效果。     

延庆监狱地热——水源热泵供暖系统工程设计与应用

该项目以地热水间接换热,在地热水供热量不能满足负荷时,采用高温水源热泵系统对地热尾水的热量进行回收,从而增加了地热水的梯级利用。同时本文对该方案与常规供暖方式的运行费用进行了比较。     

空气源热泵冷热水机组压缩机运行故障分析

分析了压缩机运行中出现故障的原因，给出了改进热泵机组及压缩机的措施，为合理选择热泵机组的压缩机及合理配置系统提供了依据。     

CO2跨临界水源热泵两级供热系统理论比较

在供热系统中，需要的水温较高时，由于回水温度高而导致CO2跨临界水源热泵能效比下降。如果降低回不温度，就要求不同温度的热水分级处理。CO2跨临界水源热泵两级供热系统可以实现能量的分级利用。分析对比了3种形工的CO2跨临界水源热泵两级供热系统，发现它们各有特点，可根据不同的使用要求采用适宜的两组系统。     

重庆地区地表水地源热泵系统冬季供暖工程应用

以重庆地区5个地表水地源热泵项目为例,对其冬季供暖运行工况进行了实测,并与空气源热泵和锅炉供暖进行了比较.结果表明,江水源热泵系统的机组制热性能系数COP和系统制热能效比EER分别能达到2.8～5.3和2.7～4.3,湖水源热泵系统的COP和EER分别能达到4.4和3.0,并且室内温度和相对湿度分别能保持在20℃左右和40％以上;相比于空气源热泵和锅炉供暖,地表水地源热泵系统冬季供暖的能效提高率分别达到了8.0％～72.0％和18.0％～87.9％,节能显著.     

风冷燃气机驱动压缩式热泵冷热水机组运行特性试验研究

对采用国产制冷机及部件设计研制的热泵冷热水机组进行了调试、试运行及运行特性测试,结果表明,机组设计合理、性能可靠,提高供水温度的措施是可行的,在不计燃气缸体冷却热的条件下,一次能源利用系数仅供热时达0.97,同时供热供冷时可达1.74。     

风冷热泵冷热水机组自调整模糊除霜控制研究

回顾了空气热源热泵除霜控制方法,提出了自调整除霜控制的思想,介绍了系统的基本结构,输入论域的确定,输入量的模糊化和模糊推理方法,在高位机上实现了模糊除霜控制的仿真,并与实验数据进行了对比,表明自调整模糊除霜控制方法先进、可行。     

空气源热泵冷热水机组设计选型

讨论了设计选型中常常遇到的机组制冷量、制热量、噪声、除霜措施、压缩机、性能系数、节流装置、内置水泵、防腐、布置等技术问题     

水源热泵技术在开滦集团公司的应用分析

介绍了水源热泵的基本原理和系统流程,并结合其在开滦集团公司的应用情况,指出采用水源热泵技术取得了显著的节能效果,且事故率大幅降低,为今后煤矿矿井水的利用起到了示范、推动作用。     

Simulation of hybrid ground-coupled heat pump with domestic hot water heating systems using HVACSIM+

A hybrid ground-coupled heat pump (HGCHP) with domestic hot water (DHW) supply system has been proposed in this paper for space cooling/heating and DHW supply for residential buildings in hot-climate areas. A simulation model for this hybrid system is established within the HVACSIM+ environment. A sample system, applied for a small residential apartment located in Hong Kong, is hourly simulated in a typical meteorological year. The conventional GCHP system and an electric heater for DHW supply are also modeled and simulated on an hourly basis within the HVACSIM+ for comparison purpose. The results obtained from this case study show that the HGCHP system can effectively alleviate the imbalanced loads of the ground heat exchanger (GHE) and can offer almost 95% DHW demand. The energy saving for DHW heating is about 70% compared with an electric heater. This proposed scheme, i.e. the HGCHP with DHW supply, is suitable to residential buildings in hot-climate areas, such as in Hong Kong.