Abstract: The enthalpy difference method is used to test the performance of R290 variable frequency air conditioning under varying working conditions. MATLAB software is used to fit the performance curve of the air conditioning system. Energy Plus software is used to build the air conditioning room model and the fitted air conditioning model. The results show that when the air conditioner is set at 20℃, the annual power consumption of refrigeration is the highest in Guangzhou, which is 2.18 times of that in Chengdu. In Shanghai, Chengdu and Guangzhou, the power consumption of air conditioning system decreases by about 19.2%, 17.1% and 20.1% when the set temperature of air conditioning rises by 2℃ respectively. The simulation of the use habit of office workers to turn on air conditioning from 6 PM to 6 AM shows that the power consumption of Beijing, Shanghai and Chengdu is the same, and Guangzhou is the highest, which is about 1.6 times of Beijing.

Key words: R290, Variable frequency air conditioner, Annual energy consumption under refrigeration conditions, Simulation