Dynamic Simulation And Refrigeration Characteristics On Inverter Room Air-conditioner In SIMULINK Program

Air-conditioners are becoming more and more necessary in people's daily life because of its contribution to improve indoor air environment for working and living. Since the energy consumption of air-containers increases greatly year by year, more and more attention was attracted to energy-saving issue of air-conditioning systems. Inverter air-conditioner is popularized recently due to its energy saving, comfortable and so on.Taking account of frequency control strategy, an integrated dynamic model has been proposed for an inverter room air-conditioner, which appropriately combined with refrigeration system, air-conditioning room, and outside environment.Based on the established simulation model, the start-up performance under fixed frequency and changing frequency was analyzed. The parameters varying along with frequency and COP comparison on one typical working day under the fixed frequency and changing frequency was studied carefully. As a result, the average COP reduces by 37.15% at changing frequency compared with that at fixed frequency, which can be ascribed to the high-frequency running in the starting-up process, meanwhile. Therefore the cooling time is shortened to reach the set room temperature 27℃. and the thermal comfort is enhanced. The cooling time is saved by 204 seconds for changing-frequency running. Analyzing the parameters changing along with frequency, the true reason of energy-saving by inverter air-conditioner can be concluded: the COP of air-containing system for long-term running increases at low frequency and high efficiency. In a typical working day, the COP of inverter room air-conditioner increases by 34%, and the room temperature fluctuation is restricted within 1℃. Hence the better thermal comfort is achieved.