变频空调器间歇运行能耗特征模拟分析

Simulation analysis on energy consumption characteristics of frequency-conversion air conditioner under intermittent operation

近年来,变频空调器已逐渐在住宅和小型办公建筑中普及。在压缩机高频运行时,变频空调器的能效比较低是变频空调器的一个显著特征。基于此特征,在利用变频空调器供冷的过程中,通过使空调器间歇运行这种节能方式有时并不能达到预期的节能目的。本文采用有限元仿真软件COMSOL Multiphysics和MATLAB联合仿真,计算空调器停机前的运行时间以及停机持续时间对变频空调器用电量的影响。计算结果表明,在空调器运行频率快速下降的阶段关闭空调器,容易造成间歇运行时变频空调器的用电量高于连续运行时变频空调器的用电量。在给定的一个运行周期中,与变频空调器连续运行相比,变频空调器间歇运行时的总供冷量的降低率低于整个周期变频空调器平均能效比的降低率时,空调器间歇运行这种节能方式无法有效降低变频空调器的用电量。

The frequency-conversion air conditioners have been widely applied to residential buildings and small office buildings in recent years.When the compressor runs in high frequency,the energy efficiency ratio(EER)of the frequency-conversion air conditioner decreases significantly.Therefore,the intermittent operation may not work in energy conservation when using the frequency-conversion air conditioner for cooling.The influence of the durations of the air conditioner first running period and the off-period on the electricity consumption is calculated by combined simulation of COMSOL Multiphysics and MATLAB.The calculation results show that if turn off the air conditioner during the quick reduction period of operation frequency of air conditioner,it will easily cause more electricity consumption under intermittent operation than that under continuous operation.During a certain operation cycle,when the reduction rate of the total cooling capacity of the frequency-conversion air conditioner is lower than the reduction rate in the average energy efficiency ratio(EER)in the whole on-off-on process,the electricity consumption of frequency-conversion air conditioner using the intermittent operation way cannot be reduced effectively compared with using the continuous operation way.