Experimental study on energy storage and defrosting characteristics of cascade air-source heat pump at different outdoor temperatures(1)：Heating/energy storage mode

Presents the working principle and the system structure. Experimentally studies the characteristics of conventional heating mode and thermal energy storage mode under two outdoor temperature conditions. The results indicate that in thermal energy storage mode, the unit can operate normally under two conditions, with little influence on suction and exhaust pressure and temperature both in the low temperature cycle and the high temperature cycle. Under the two conditions, the average heat capacity in thermal energy storage mode accounts for more than 97% of that in the conventional heating mode, and the thermal energy storage process has little effect on heating process. The system can operate normally in the low temperature range of -18 to -9 ℃, and the minimum heat to capacity of heat storage tank is up to 3 413 kJ, which meets the requirement of design.