Multi-mode accurate defrosting start-stop management method and system of air source heat pump

Abstract

The invention provides a multi-mode accurate defrosting start-stop management method and system of an air source heat pump. The method comprises the steps that S1, a heat pump defrosting operation parameter threshold value and a defrosting start condition are set; S2, the initial operation state, the initial defrosting mark and the operation time of the heat pump are obtained; S3, the evaporator air inlet temperature and the evaporator air outlet temperature are obtained; and S4, whether the initial defrosting mark is yes or not is judged, if yes, whether the operation time of the heat pump, the evaporator air inlet temperature, the air outlet temperature and the evaporator air inlet and outlet temperature difference meet the standard defrosting start condition or not is judged, if yes, defrosting is started, if not, whether the operation time of the heat pump and the evaporator air inlet temperature meet the initial defrosting start condition or not is judged, and if yes, defrosting is started. According to the method, the defrosting opportunity is jointly judged based on the evaporator air inlet and outlet temperature difference or by being assisted by the refrigerant pipe temperature, the operation time, the initial defrosting mark and the like, defrosting can be conducted accurately, misjudgment is effectively avoided, installation and collection are easy, the price is low,and good practicability is achieved.

Description

technical field [0001] The invention belongs to the technical field of heat pump defrosting, and in particular relates to a start-stop management method for multi-mode precise defrosting of an air source heat pump. Background technique [0002] Air source heat pump is a clean and energy-saving technology that can be used in a wide range of fields such as production / domestic hot water, building heating, and agricultural drying. In recent years, it has played a key role in coal-to-electric heating in northern China, and has made important contributions to the alleviation of winter smog and the advancement of energy conservation and emission reduction. [0003] The heat produced by the air source heat pump is to absorb heat from the air through the evaporator. The surface temperature of the evaporator is often lower than the dew point of the air. When the surface temperature of the evaporator is lower than the freezing point of water at the same time, frost will form on the sur...

AI Technical Summary

Problems solved by technology

Failure to defrost in time will lead to a decrease in the heat transfer coefficient of the evaporator, a decrease in evaporation temperature, a decrease in system energy efficiency, and a decrease in heating capacity; Heating capacity drops

Existing systems mostly use timing defrosting or defrosting according to the evaporation temperature, which may easily lead to untimely defrosting or excessive defrosting

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