Abstract: By setting the temperature fluctuation of 3 P environment simulation room within 2℃ as the goal to achieve the effect of "no effect frost", the paraffin with phase change temperature of 46℃ is selected as the heat storage material, and the heat accumulator in line with the outer space of 3 P air conditioner is designed by theoretical calculation. Through experimental verification, the room temperature fluctuation, air outlet temperature and 24 h continuous heating operation attenuation of the heat storage defrosting system are analyzed. Compared with the traditional reverse defrosting system, the outdoor defrosting temperature fluctuation at 2℃ is compared. The experiment shows that the temperature fluctuation of the thermal storage defrosting system at 2℃ is as low as 1℃, significantly lower than 5.67℃ of the traditional reverse defrosting system, and the minimum air outlet temperature of the thermal storage defrosting system is above 39.1℃, which can meet the 24 h long-time operation and the fluctuation is less than 1℃.

Key words: Variable frequency air conditioner, Temperature fluctuation, Heat storage and defrosting, Continuous operation, Air outlet temperature