低温制热工况空调器最佳除霜起始点的实验研究

Experimental Research on Optimal Defrosting Starting Point for Air Conditioner in Low Temperature Heating Condition

低温制热工况下空调外机结霜会导致系统性能显著恶化。为保持系统性能,除霜策略诸如除霜起始点和持续时间的决定是很重要的措施。这类措施使得更舒适的供暖工况成为可能。本文通过理论分析与实验研究相结合的方法,提出了利用最大平均制热量法快速确定最佳除霜起始点的方法。研究结果表明,在低温制热工况下,采用本文的除霜起始点确定方法后,只通过两次实验就使所测试的1.5匹空调器的平均制热量提升至3,213 W,能满足空调器标称要求;空调器的平均能效提高了6%。采用最大平均制热量法可以快速高效地确定最佳除霜起始点。

The system performance will be significantly deteriorated due to the frosting on outdoor unit of air conditioner under low temperature heating conditions. To maintain the system performance, the defrosting strategy, such as the start point and duration, is very important solution. This solution makes it possible to realize more comfortable heating condition. Based on the experiment and theory analysis, the method to find the best start point for defrosting by using optimal average heating capacity methodology was proposed. The research results show that, in low temperature condition, the best point was found with in 2 trials by adopting the proposed method; the average heating capacity of the tested 1.5 HP air conditioner is increased up to 3,213 W, which meets the requirement for the air conditioner; the average energy efficiency is increased by 6%. The optimal average heating capacity method is a practical and efficient way to determine best deforesting strategy for an air conditioner system.