Control method for guaranteeing stable operation of air source heat pump at low exhaust temperature of -40 DEG C

Abstract

The invention discloses a control method for guaranteeing stable operation of an air source heat pump at the low exhaust temperature of -40 DEG C, and belongs to the technical field of low-temperatureoperation. A compressor communicates with an indoor heat exchanger, an outdoor heat exchanger and an economizer, and the indoor heat exchanger communicates with the economizer. The economizer communicates with the outdoor heat exchanger. When a unit operates, the outdoor temperature is measured; if the outdoor temperature is higher than a set value, the opening degree of a main electronic expansion valve is adjusted, and the exhaust temperature is adjusted; if the outdoor temperature is not lower than 60 DEG C, the opening degree of an air supply electronic expansion valve is adjusted, and air supply is carried out on the compressor; if the outdoor temperature is lower than 60 DEG C, air supply is not carried out on the compressor, and the process is finished if the standard is met; and if the outdoor temperature is lower than the set value, the opening degree of the main electronic expansion valve and the opening degree of the air supply electronic expansion valve are adjusted, the oil temperature is judged, and the process is finished if the standard is met. According to the control method, the air source heat pump can still stably operate in the low-temperature environment of -40 DEG C, the low-temperature performance of the unit is greatly improved, and the stability of unit operation is improved; and wet compression is avoided, and the advantages of being easy to control,high in practicality, high in stability and the like are achieved.

Description

technical field [0001] The invention relates to a control method for ensuring stable operation of an air source heat pump at a low exhaust temperature of -40°C, and belongs to the technical field of low temperature operation. Background technique [0002] When the air source heat pump unit is heating in a low temperature environment, there is a problem that it cannot operate due to the large compression ratio and the high exhaust temperature. Aiming at this problem, the most important solution both at home and abroad is to adopt quasi-two-stage (two-stage) compression technology. The quasi-two-stage (two-stage) compression technology can reduce the exhaust temperature of the compressor within a certain range, so that the air source heat pump can operate stably at an ambient temperature above -20°C. However, for severe cold areas where the ambient temperature is -30°C or even lower, quasi-two-stage (two-stage) compressed air source heat pumps still cannot operate stably beca...

AI Technical Summary

Problems solved by technology

However, for severe cold areas where the ambient temperature is -30°C or even lower, the quasi-two-stage (two-stage) compressed air source heat pump will still fail to operate stably due to the high exhaust temperature.

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