Abstract:

An air-source heat pump (ASHP) is an energy-saving device that utilizes energy of higher grade to move energy from a lower heat source, which is air, to a higher heat source. This article describes the concept of small-scale ASHP for low ambient temperature (input power at 1-4 kW, environment temperature down to -20℃) and its energy efficiency evaluation method. Two suitable types of fully enclosed compressors are introduced:rotary compressors and scroll compressors. The compression principles of the two compressors were compared. Through technical analysis and product research, the basic characteristics, the enhanced vapor injection (EVI) and the liquid injection technologies, the frequency conversion technology and the applicable operating conditions of the two compressors were analyzed. The characteristics of their variable compression ratio (VCR) are described. The manufacturing processes of the two compressors are compared. A comparison of applicability for the two compressors is presented.

摘要：

空气源热泵是一种利用高位能使能量从低位热源空气流向高位热源的节能装置。阐述了小型低环境温度空气源热泵（输入功率在1～4 kW，工作环境温度可达−20 ℃）的概念和用能效率评定方式。介绍了适用于小型低环境温度空气源热泵的两种全封闭压缩机：转子压缩机和涡旋压缩机。对比了两类压缩机的压缩原理；通过技术分析和产品调研，对两类压缩机的基本特性、喷气增焓和喷液增焓技术、变频技术和适用工况等方面进行了分析，并对其变压比特性进行阐述；对其制造工艺进行比较。得出了两种压缩机的适用性对比。