The independently parallel hot gas defrosting of air-cooled heat pump system
Technical field:
The utility model relates to the independently parallel hot gas defrosting of a kind of air-cooled heat pump system, it is an independent hot gas defrosting condenser in parallel on air-cooled condenser, utilize the hot working fluid air-flow of the HTHP of refrigeration compressor outlet to remove collection frost on the air-cooled condenser of heat pump through independent hot gas defrosting condenser, thereby keep the normal operation of air-cooled heat pump, belong to refrigeration and cryogenic technique field.
Background technology:
The evaporimeter of the air-cooled heat pump that generally uses winter all can be because of solid wall temperature be lower than the zero degree frosting now, if do not defrost immediately, and then frost can cumulative its operate as normal that has a strong impact on.The defrosting measure of air-cooled heat pump evaporimeter now mainly contains electric defrosting and the contrary operation defrosting of heat pump two classes, and the former expends more energy because of using accessory power supply, is unfavorable for energy-conservation and environmental protection; And the latter changes the operation of heat pump system into the refrigeration modes operation with transfer valve, and this not only makes system's operation complicated, makes operation of heat pump discontinuous again, can greatly reduce the service efficiency of equipment.
Summary of the invention:
In order to remedy above-mentioned the deficiencies in the prior art, the utility model will provide a kind of not to be stopped the normal operation of heat pump and can utilize the independent hot gas defrosting condenser in parallel with the air-cooled condenser of heat pump to realize the defrosting of evaporator with heat pump.
As the Hang Time of Yun under the heat pump operating mode of system, if environment temperature is lower, will frosting on the evaporator fin, open then that the Working medium gas of HTHP just from the independent hot gas defrosting condenser of parallel connection flow through and frost condenser on disposed if hot gas defrosting valve K5, K6 are closed K7, K8 this moment; Before defrosting, independent hot gas defrosting condenser can be used as replenishing of air-cooled condenser, to pass through the reducing transformer throttling earlier owing to flow into the working medium of independent hot gas defrosting condenser, so its evaporating temperature is lower than air-cooled condenser, the frosting of system at first takes place on independent hot gas defrosting condenser, when the frost on it is tied to a certain degree, can enable the defrosting control valve and remove frost on the independent hot gas defrosting condenser, reach the purpose that can defrost and not influence the heat pump operate as normal.
Description of drawings:
Accompanying drawing 1 is the independent parallel hot gas defrosting system diagram of air-cooled heat pump.Wherein: the 1--refrigeration compressor; The air-cooled condenser of 2--; 3--independence hot gas defrosting condenser; 4--defrosting control valve K5, K6, K7, K8; The 5--throttling arrangement; The 6--evaporimeter; 7--heat pump cycle reversal valve K1, K2, K3, K4; 8--Ya Li Ping Red device; The 9--reducing transformer.。
The outlet of refrigeration compressor 1 respectively with the K7 inlet UNICOM of K1, the K2 of heat pump cycle reversal valve 7 and defrosting control valve 4, and the outlet of the outlet of K1 and Ya Li Ping Red device 8, the K5 of defrosting control valve 4 and the K4 UNICOM of heat pump cycle reversal valve 7, the inlet of Ya Li Ping Red device 8 and the outlet UNICOM of air-cooled condenser 2 are after link with the suction port of compressor behind throttling arrangement 5, evaporimeter 6 and the heat pump cycle reversal valve K3, the outlet one tunnel of defrosting control valve K7 behind defrosting control valve K5 with the inlet UNICOM of Ya Li Ping Red device 8, the inlet UNICOM of another road and independent hot gas defrosting condenser 3; The outlet of heat pump cycle reversal valve K2 and the outlet UNICOM of evaporimeter 6 link through heat pump cycle reversal valve K3 and refrigeration compressor inlet then, and heat pump cycle reversal valve K4 links outlet and the refrigeration compressor inlet of K1.
2.
Case study on implementation:
Fig. 1 also is the independent parallel hot gas defrosting system diagram of 25kW air-cooled heat pump.
When K1, the K3 of heat pump cycle reversal valve 7 close, system moved under the heat pump operating mode when K2, K4 opened, it is liquid that the high temperature refrigerant gas that refrigeration compressor 1 is discharged enters the water condensation that is cooled in the evaporimeter 6 through K2, flow into evaporation in the air-cooled condenser 2 after throttling arrangement 5 step-downs, the inlet of air-cooled condenser 2 links with the inlet of refrigeration compressor 1 behind K4; If independent hot gas defrosting condenser 3 is not also before the frosting, the K5 of defrosting control valve 4, K6 opens and K7, K8 closes, liquid working substance also can be through K6, reducing transformer 9, independent hot gas defrosting condenser 3, K5, K4 returns the inlet of refrigeration compressor 1, this moment, the evaporating temperature of independent hot gas defrosting condenser 3 was lower slightly than air-cooled condenser 2, so frost should generate at first in its surface, when frost length arrives certain thickness, controller will send the defrosting instruction, make K5, K6 closes and K7, K8 opens, to through K7 enter independent hot gas defrosting condenser 3 in from the high temperature refrigerant gas that refrigeration compressor 1 flows out this moment, make it behind the hot gas defrosting again through K8, throttling arrangement 5, air-cooled condenser 2, enter the inlet of refrigeration compressor 1 behind the K4.