Heat pump air-conditioning system and control method thereof

Abstract

The invention provides a heat pump air-conditioning system and a control method thereof. The heat pump air-conditioning system comprises a refrigerant circulation loop formed by a compressor, a four-way valve, an indoor heat exchanger and an outdoor heat exchanger which are connected through a pipeline, wherein a refrigerant heater and a first throttling device are sequentially connected in series with the pipeline between the four-way valve and the outdoor heat exchanger; the pipeline between the indoor heat exchanger and the outdoor heat exchanger is connected in series with a second throttling device capable of adjusting flow; the refrigerant heater and the first throttling device are further connected in parallel with a by-pass pipeline; the by-pass pipeline is provided with a control valve used for controlling on-off of the by-pass pipeline; the heat pump air-conditioning system further comprises a controller used for controlling flow of the second throttling device and actions of the control valve as well as opening or closing of the refrigerant heater. According to the heat pump air-conditioning system and the control method thereof, which are provided by the invention, a refrigerant heating control process is utilized to realize the operation mode, including refrigeration, heating or non-reversing defrosting, of an air conditioner, and the indoor heat exchanger can continuously supply heat while defrosting is performed, so that comfort of a room is ensured.

Description

technical field [0001] The invention belongs to the technical field of air-conditioning equipment, and more specifically relates to a heat pump air-conditioning system with a refrigerant heating function and a control method thereof. Background technique [0002] When the air conditioner of the heat pump air conditioning system (hereinafter referred to as the air conditioner) is used under low temperature conditions, after a period of operation, the heat exchanger of the external unit will frost, which increases the thermal resistance and wind resistance, which is not conducive to heat exchange. In order to make the air conditioner operate normally, it is often necessary to remove and melt the frost of the external unit. [0003] The main defrosting method of the existing air conditioner is to switch the four-way valve to carry out the refrigeration cycle. Although such a defrosting method can completely remove the frost on the heat exchanger, the indoor unit stops running ...

AI Technical Summary

Problems solved by technology

Although this method can also achieve non-reversing defrosting, and the indoor unit continues to supply heat, but the structure is cumbersome, and the flow control of the exhaust bypass is very complicated, and the practical operability is not strong.

Images