采用R410A单一工质的复叠式空气源热泵

针对空气源热泵在寒冷地区应用中存在的诸多问题，结合复叠式循环与压缩机直流调速技术，提出一种采用R410A单一工质的复叠式空气源热泵(SC-ASHP)系统，既可以按照传统单级压缩制热（SHC）模式运行,又可按复叠式制热（CHC）模式运行。不同工况下，对SC-ASHP系统在两种不同制热模式运行时的压缩比、排气温度、制热量与性能系数（COP）进行了模拟计算与实验研究，结果表明：低温环境下，CHC模式压缩比和排气温度远低于SHC模式；在冷凝温度46℃，蒸发温度-35℃工况下，CHC模式COP高于1.8，压缩机排气温度低于120℃，高低温压缩机压缩比均不超过5.0，系统可以稳定可靠运行；此外，CHC模式下提高低温压缩机转速可以持续提高系统制热量，满足低温环境下的供暖需求；新系统扩大了空气源热泵系统的应用范围。

Cascade air-source heat pump with R410A single fluid

In the light of the problems existing in the application of air source heat pump in cold regions, a new single-fluid cascade air-source heat pump (SC-ASHP) has been developed, combining with cascade cycle and compressor DC speed regulation technology. The new-type heat pump can operate not only in a single-stage heating cycle (SHC) mode, but also in a cascade heating cycle (CHC) mode. Under different operating conditions, simulation calculations and experimental studies were performed on the compression ratio, exhaust temperature, heating capacity, and coefficient of performance (COP) of the SC-ASHP system in two different heating modes. The results show that, in low temperature environment, the compressor discharge temperature and the compression ratio of the CHC mode are much lower than the SHC mode; when the condensing temperature of 46℃ and an evaporating temperature of -35℃, COP of the CHC mode is higher than 1.8, the compressor discharge temperature is lower than 120℃, and the compression ratio is not more than 5.0, the system can operate stably and reliably; in addition, the heating capacity is rising steadily by increasing the speed of the low temperature compressor in low temperature environment, meeting the heating supply. New heat pump system expanded the application range of air source heat pump system.